~bzr-pqm/bzr/bzr.dev

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
# Copyright (C) 2006-2011 Canonical Ltd
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

import bz2

from bzrlib import (
    bencode,
    branch,
    bzrdir as _mod_bzrdir,
    config,
    controldir,
    debug,
    errors,
    graph,
    lock,
    lockdir,
    repository as _mod_repository,
    revision as _mod_revision,
    static_tuple,
    symbol_versioning,
    urlutils,
)
from bzrlib.branch import BranchReferenceFormat, BranchWriteLockResult
from bzrlib.decorators import needs_read_lock, needs_write_lock, only_raises
from bzrlib.errors import (
    NoSuchRevision,
    SmartProtocolError,
    )
from bzrlib.lockable_files import LockableFiles
from bzrlib.smart import client, vfs, repository as smart_repo
from bzrlib.smart.client import _SmartClient
from bzrlib.revision import NULL_REVISION
from bzrlib.repository import RepositoryWriteLockResult
from bzrlib.trace import mutter, note, warning


class _RpcHelper(object):
    """Mixin class that helps with issuing RPCs."""

    def _call(self, method, *args, **err_context):
        try:
            return self._client.call(method, *args)
        except errors.ErrorFromSmartServer, err:
            self._translate_error(err, **err_context)

    def _call_expecting_body(self, method, *args, **err_context):
        try:
            return self._client.call_expecting_body(method, *args)
        except errors.ErrorFromSmartServer, err:
            self._translate_error(err, **err_context)

    def _call_with_body_bytes(self, method, args, body_bytes, **err_context):
        try:
            return self._client.call_with_body_bytes(method, args, body_bytes)
        except errors.ErrorFromSmartServer, err:
            self._translate_error(err, **err_context)

    def _call_with_body_bytes_expecting_body(self, method, args, body_bytes,
                                             **err_context):
        try:
            return self._client.call_with_body_bytes_expecting_body(
                method, args, body_bytes)
        except errors.ErrorFromSmartServer, err:
            self._translate_error(err, **err_context)


def response_tuple_to_repo_format(response):
    """Convert a response tuple describing a repository format to a format."""
    format = RemoteRepositoryFormat()
    format._rich_root_data = (response[0] == 'yes')
    format._supports_tree_reference = (response[1] == 'yes')
    format._supports_external_lookups = (response[2] == 'yes')
    format._network_name = response[3]
    return format


# Note that RemoteBzrDirProber lives in bzrlib.bzrdir so bzrlib.remote
# does not have to be imported unless a remote format is involved.

class RemoteBzrDirFormat(_mod_bzrdir.BzrDirMetaFormat1):
    """Format representing bzrdirs accessed via a smart server"""

    supports_workingtrees = False

    def __init__(self):
        _mod_bzrdir.BzrDirMetaFormat1.__init__(self)
        # XXX: It's a bit ugly that the network name is here, because we'd
        # like to believe that format objects are stateless or at least
        # immutable,  However, we do at least avoid mutating the name after
        # it's returned.  See <https://bugs.launchpad.net/bzr/+bug/504102>
        self._network_name = None

    def __repr__(self):
        return "%s(_network_name=%r)" % (self.__class__.__name__,
            self._network_name)

    def get_format_description(self):
        if self._network_name:
            real_format = controldir.network_format_registry.get(self._network_name)
            return 'Remote: ' + real_format.get_format_description()
        return 'bzr remote bzrdir'

    def get_format_string(self):
        raise NotImplementedError(self.get_format_string)

    def network_name(self):
        if self._network_name:
            return self._network_name
        else:
            raise AssertionError("No network name set.")

    def initialize_on_transport(self, transport):
        try:
            # hand off the request to the smart server
            client_medium = transport.get_smart_medium()
        except errors.NoSmartMedium:
            # TODO: lookup the local format from a server hint.
            local_dir_format = _mod_bzrdir.BzrDirMetaFormat1()
            return local_dir_format.initialize_on_transport(transport)
        client = _SmartClient(client_medium)
        path = client.remote_path_from_transport(transport)
        try:
            response = client.call('BzrDirFormat.initialize', path)
        except errors.ErrorFromSmartServer, err:
            _translate_error(err, path=path)
        if response[0] != 'ok':
            raise errors.SmartProtocolError('unexpected response code %s' % (response,))
        format = RemoteBzrDirFormat()
        self._supply_sub_formats_to(format)
        return RemoteBzrDir(transport, format)

    def parse_NoneTrueFalse(self, arg):
        if not arg:
            return None
        if arg == 'False':
            return False
        if arg == 'True':
            return True
        raise AssertionError("invalid arg %r" % arg)

    def _serialize_NoneTrueFalse(self, arg):
        if arg is False:
            return 'False'
        if arg:
            return 'True'
        return ''

    def _serialize_NoneString(self, arg):
        return arg or ''

    def initialize_on_transport_ex(self, transport, use_existing_dir=False,
        create_prefix=False, force_new_repo=False, stacked_on=None,
        stack_on_pwd=None, repo_format_name=None, make_working_trees=None,
        shared_repo=False):
        try:
            # hand off the request to the smart server
            client_medium = transport.get_smart_medium()
        except errors.NoSmartMedium:
            do_vfs = True
        else:
            # Decline to open it if the server doesn't support our required
            # version (3) so that the VFS-based transport will do it.
            if client_medium.should_probe():
                try:
                    server_version = client_medium.protocol_version()
                    if server_version != '2':
                        do_vfs = True
                    else:
                        do_vfs = False
                except errors.SmartProtocolError:
                    # Apparently there's no usable smart server there, even though
                    # the medium supports the smart protocol.
                    do_vfs = True
            else:
                do_vfs = False
        if not do_vfs:
            client = _SmartClient(client_medium)
            path = client.remote_path_from_transport(transport)
            if client_medium._is_remote_before((1, 16)):
                do_vfs = True
        if do_vfs:
            # TODO: lookup the local format from a server hint.
            local_dir_format = _mod_bzrdir.BzrDirMetaFormat1()
            self._supply_sub_formats_to(local_dir_format)
            return local_dir_format.initialize_on_transport_ex(transport,
                use_existing_dir=use_existing_dir, create_prefix=create_prefix,
                force_new_repo=force_new_repo, stacked_on=stacked_on,
                stack_on_pwd=stack_on_pwd, repo_format_name=repo_format_name,
                make_working_trees=make_working_trees, shared_repo=shared_repo,
                vfs_only=True)
        return self._initialize_on_transport_ex_rpc(client, path, transport,
            use_existing_dir, create_prefix, force_new_repo, stacked_on,
            stack_on_pwd, repo_format_name, make_working_trees, shared_repo)

    def _initialize_on_transport_ex_rpc(self, client, path, transport,
        use_existing_dir, create_prefix, force_new_repo, stacked_on,
        stack_on_pwd, repo_format_name, make_working_trees, shared_repo):
        args = []
        args.append(self._serialize_NoneTrueFalse(use_existing_dir))
        args.append(self._serialize_NoneTrueFalse(create_prefix))
        args.append(self._serialize_NoneTrueFalse(force_new_repo))
        args.append(self._serialize_NoneString(stacked_on))
        # stack_on_pwd is often/usually our transport
        if stack_on_pwd:
            try:
                stack_on_pwd = transport.relpath(stack_on_pwd)
                if not stack_on_pwd:
                    stack_on_pwd = '.'
            except errors.PathNotChild:
                pass
        args.append(self._serialize_NoneString(stack_on_pwd))
        args.append(self._serialize_NoneString(repo_format_name))
        args.append(self._serialize_NoneTrueFalse(make_working_trees))
        args.append(self._serialize_NoneTrueFalse(shared_repo))
        request_network_name = self._network_name or \
            _mod_bzrdir.BzrDirFormat.get_default_format().network_name()
        try:
            response = client.call('BzrDirFormat.initialize_ex_1.16',
                request_network_name, path, *args)
        except errors.UnknownSmartMethod:
            client._medium._remember_remote_is_before((1,16))
            local_dir_format = _mod_bzrdir.BzrDirMetaFormat1()
            self._supply_sub_formats_to(local_dir_format)
            return local_dir_format.initialize_on_transport_ex(transport,
                use_existing_dir=use_existing_dir, create_prefix=create_prefix,
                force_new_repo=force_new_repo, stacked_on=stacked_on,
                stack_on_pwd=stack_on_pwd, repo_format_name=repo_format_name,
                make_working_trees=make_working_trees, shared_repo=shared_repo,
                vfs_only=True)
        except errors.ErrorFromSmartServer, err:
            _translate_error(err, path=path)
        repo_path = response[0]
        bzrdir_name = response[6]
        require_stacking = response[7]
        require_stacking = self.parse_NoneTrueFalse(require_stacking)
        format = RemoteBzrDirFormat()
        format._network_name = bzrdir_name
        self._supply_sub_formats_to(format)
        bzrdir = RemoteBzrDir(transport, format, _client=client)
        if repo_path:
            repo_format = response_tuple_to_repo_format(response[1:])
            if repo_path == '.':
                repo_path = ''
            if repo_path:
                repo_bzrdir_format = RemoteBzrDirFormat()
                repo_bzrdir_format._network_name = response[5]
                repo_bzr = RemoteBzrDir(transport.clone(repo_path),
                    repo_bzrdir_format)
            else:
                repo_bzr = bzrdir
            final_stack = response[8] or None
            final_stack_pwd = response[9] or None
            if final_stack_pwd:
                final_stack_pwd = urlutils.join(
                    transport.base, final_stack_pwd)
            remote_repo = RemoteRepository(repo_bzr, repo_format)
            if len(response) > 10:
                # Updated server verb that locks remotely.
                repo_lock_token = response[10] or None
                remote_repo.lock_write(repo_lock_token, _skip_rpc=True)
                if repo_lock_token:
                    remote_repo.dont_leave_lock_in_place()
            else:
                remote_repo.lock_write()
            policy = _mod_bzrdir.UseExistingRepository(remote_repo, final_stack,
                final_stack_pwd, require_stacking)
            policy.acquire_repository()
        else:
            remote_repo = None
            policy = None
        bzrdir._format.set_branch_format(self.get_branch_format())
        if require_stacking:
            # The repo has already been created, but we need to make sure that
            # we'll make a stackable branch.
            bzrdir._format.require_stacking(_skip_repo=True)
        return remote_repo, bzrdir, require_stacking, policy

    def _open(self, transport):
        return RemoteBzrDir(transport, self)

    def __eq__(self, other):
        if not isinstance(other, RemoteBzrDirFormat):
            return False
        return self.get_format_description() == other.get_format_description()

    def __return_repository_format(self):
        # Always return a RemoteRepositoryFormat object, but if a specific bzr
        # repository format has been asked for, tell the RemoteRepositoryFormat
        # that it should use that for init() etc.
        result = RemoteRepositoryFormat()
        custom_format = getattr(self, '_repository_format', None)
        if custom_format:
            if isinstance(custom_format, RemoteRepositoryFormat):
                return custom_format
            else:
                # We will use the custom format to create repositories over the
                # wire; expose its details like rich_root_data for code to
                # query
                result._custom_format = custom_format
        return result

    def get_branch_format(self):
        result = _mod_bzrdir.BzrDirMetaFormat1.get_branch_format(self)
        if not isinstance(result, RemoteBranchFormat):
            new_result = RemoteBranchFormat()
            new_result._custom_format = result
            # cache the result
            self.set_branch_format(new_result)
            result = new_result
        return result

    repository_format = property(__return_repository_format,
        _mod_bzrdir.BzrDirMetaFormat1._set_repository_format) #.im_func)


class RemoteBzrDir(_mod_bzrdir.BzrDir, _RpcHelper):
    """Control directory on a remote server, accessed via bzr:// or similar."""

    def __init__(self, transport, format, _client=None, _force_probe=False):
        """Construct a RemoteBzrDir.

        :param _client: Private parameter for testing. Disables probing and the
            use of a real bzrdir.
        """
        _mod_bzrdir.BzrDir.__init__(self, transport, format)
        # this object holds a delegated bzrdir that uses file-level operations
        # to talk to the other side
        self._real_bzrdir = None
        self._has_working_tree = None
        # 1-shot cache for the call pattern 'create_branch; open_branch' - see
        # create_branch for details.
        self._next_open_branch_result = None

        if _client is None:
            medium = transport.get_smart_medium()
            self._client = client._SmartClient(medium)
        else:
            self._client = _client
            if not _force_probe:
                return

        self._probe_bzrdir()

    def __repr__(self):
        return '%s(%r)' % (self.__class__.__name__, self._client)

    def _probe_bzrdir(self):
        medium = self._client._medium
        path = self._path_for_remote_call(self._client)
        if medium._is_remote_before((2, 1)):
            self._rpc_open(path)
            return
        try:
            self._rpc_open_2_1(path)
            return
        except errors.UnknownSmartMethod:
            medium._remember_remote_is_before((2, 1))
            self._rpc_open(path)

    def _rpc_open_2_1(self, path):
        response = self._call('BzrDir.open_2.1', path)
        if response == ('no',):
            raise errors.NotBranchError(path=self.root_transport.base)
        elif response[0] == 'yes':
            if response[1] == 'yes':
                self._has_working_tree = True
            elif response[1] == 'no':
                self._has_working_tree = False
            else:
                raise errors.UnexpectedSmartServerResponse(response)
        else:
            raise errors.UnexpectedSmartServerResponse(response)

    def _rpc_open(self, path):
        response = self._call('BzrDir.open', path)
        if response not in [('yes',), ('no',)]:
            raise errors.UnexpectedSmartServerResponse(response)
        if response == ('no',):
            raise errors.NotBranchError(path=self.root_transport.base)

    def _ensure_real(self):
        """Ensure that there is a _real_bzrdir set.

        Used before calls to self._real_bzrdir.
        """
        if not self._real_bzrdir:
            if 'hpssvfs' in debug.debug_flags:
                import traceback
                warning('VFS BzrDir access triggered\n%s',
                    ''.join(traceback.format_stack()))
            self._real_bzrdir = _mod_bzrdir.BzrDir.open_from_transport(
                self.root_transport, _server_formats=False)
            self._format._network_name = \
                self._real_bzrdir._format.network_name()

    def _translate_error(self, err, **context):
        _translate_error(err, bzrdir=self, **context)

    def break_lock(self):
        # Prevent aliasing problems in the next_open_branch_result cache.
        # See create_branch for rationale.
        self._next_open_branch_result = None
        return _mod_bzrdir.BzrDir.break_lock(self)

    def _vfs_cloning_metadir(self, require_stacking=False):
        self._ensure_real()
        return self._real_bzrdir.cloning_metadir(
            require_stacking=require_stacking)

    def cloning_metadir(self, require_stacking=False):
        medium = self._client._medium
        if medium._is_remote_before((1, 13)):
            return self._vfs_cloning_metadir(require_stacking=require_stacking)
        verb = 'BzrDir.cloning_metadir'
        if require_stacking:
            stacking = 'True'
        else:
            stacking = 'False'
        path = self._path_for_remote_call(self._client)
        try:
            response = self._call(verb, path, stacking)
        except errors.UnknownSmartMethod:
            medium._remember_remote_is_before((1, 13))
            return self._vfs_cloning_metadir(require_stacking=require_stacking)
        except errors.UnknownErrorFromSmartServer, err:
            if err.error_tuple != ('BranchReference',):
                raise
            # We need to resolve the branch reference to determine the
            # cloning_metadir.  This causes unnecessary RPCs to open the
            # referenced branch (and bzrdir, etc) but only when the caller
            # didn't already resolve the branch reference.
            referenced_branch = self.open_branch()
            return referenced_branch.bzrdir.cloning_metadir()
        if len(response) != 3:
            raise errors.UnexpectedSmartServerResponse(response)
        control_name, repo_name, branch_info = response
        if len(branch_info) != 2:
            raise errors.UnexpectedSmartServerResponse(response)
        branch_ref, branch_name = branch_info
        format = controldir.network_format_registry.get(control_name)
        if repo_name:
            format.repository_format = _mod_repository.network_format_registry.get(
                repo_name)
        if branch_ref == 'ref':
            # XXX: we need possible_transports here to avoid reopening the
            # connection to the referenced location
            ref_bzrdir = _mod_bzrdir.BzrDir.open(branch_name)
            branch_format = ref_bzrdir.cloning_metadir().get_branch_format()
            format.set_branch_format(branch_format)
        elif branch_ref == 'branch':
            if branch_name:
                format.set_branch_format(
                    branch.network_format_registry.get(branch_name))
        else:
            raise errors.UnexpectedSmartServerResponse(response)
        return format

    def create_repository(self, shared=False):
        # as per meta1 formats - just delegate to the format object which may
        # be parameterised.
        result = self._format.repository_format.initialize(self, shared)
        if not isinstance(result, RemoteRepository):
            return self.open_repository()
        else:
            return result

    def destroy_repository(self):
        """See BzrDir.destroy_repository"""
        self._ensure_real()
        self._real_bzrdir.destroy_repository()

    def create_branch(self, name=None, repository=None):
        # as per meta1 formats - just delegate to the format object which may
        # be parameterised.
        real_branch = self._format.get_branch_format().initialize(self,
            name=name, repository=repository)
        if not isinstance(real_branch, RemoteBranch):
            if not isinstance(repository, RemoteRepository):
                raise AssertionError(
                    'need a RemoteRepository to use with RemoteBranch, got %r'
                    % (repository,))
            result = RemoteBranch(self, repository, real_branch, name=name)
        else:
            result = real_branch
        # BzrDir.clone_on_transport() uses the result of create_branch but does
        # not return it to its callers; we save approximately 8% of our round
        # trips by handing the branch we created back to the first caller to
        # open_branch rather than probing anew. Long term we need a API in
        # bzrdir that doesn't discard result objects (like result_branch).
        # RBC 20090225
        self._next_open_branch_result = result
        return result

    def destroy_branch(self, name=None):
        """See BzrDir.destroy_branch"""
        self._ensure_real()
        self._real_bzrdir.destroy_branch(name=name)
        self._next_open_branch_result = None

    def create_workingtree(self, revision_id=None, from_branch=None,
        accelerator_tree=None, hardlink=False):
        raise errors.NotLocalUrl(self.transport.base)

    def find_branch_format(self, name=None):
        """Find the branch 'format' for this bzrdir.

        This might be a synthetic object for e.g. RemoteBranch and SVN.
        """
        b = self.open_branch(name=name)
        return b._format

    def get_branch_reference(self, name=None):
        """See BzrDir.get_branch_reference()."""
        if name is not None:
            # XXX JRV20100304: Support opening colocated branches
            raise errors.NoColocatedBranchSupport(self)
        response = self._get_branch_reference()
        if response[0] == 'ref':
            return response[1]
        else:
            return None

    def _get_branch_reference(self):
        path = self._path_for_remote_call(self._client)
        medium = self._client._medium
        candidate_calls = [
            ('BzrDir.open_branchV3', (2, 1)),
            ('BzrDir.open_branchV2', (1, 13)),
            ('BzrDir.open_branch', None),
            ]
        for verb, required_version in candidate_calls:
            if required_version and medium._is_remote_before(required_version):
                continue
            try:
                response = self._call(verb, path)
            except errors.UnknownSmartMethod:
                if required_version is None:
                    raise
                medium._remember_remote_is_before(required_version)
            else:
                break
        if verb == 'BzrDir.open_branch':
            if response[0] != 'ok':
                raise errors.UnexpectedSmartServerResponse(response)
            if response[1] != '':
                return ('ref', response[1])
            else:
                return ('branch', '')
        if response[0] not in ('ref', 'branch'):
            raise errors.UnexpectedSmartServerResponse(response)
        return response

    def _get_tree_branch(self, name=None):
        """See BzrDir._get_tree_branch()."""
        return None, self.open_branch(name=name)

    def open_branch(self, name=None, unsupported=False,
                    ignore_fallbacks=False):
        if unsupported:
            raise NotImplementedError('unsupported flag support not implemented yet.')
        if self._next_open_branch_result is not None:
            # See create_branch for details.
            result = self._next_open_branch_result
            self._next_open_branch_result = None
            return result
        response = self._get_branch_reference()
        if response[0] == 'ref':
            # a branch reference, use the existing BranchReference logic.
            format = BranchReferenceFormat()
            return format.open(self, name=name, _found=True,
                location=response[1], ignore_fallbacks=ignore_fallbacks)
        branch_format_name = response[1]
        if not branch_format_name:
            branch_format_name = None
        format = RemoteBranchFormat(network_name=branch_format_name)
        return RemoteBranch(self, self.find_repository(), format=format,
            setup_stacking=not ignore_fallbacks, name=name)

    def _open_repo_v1(self, path):
        verb = 'BzrDir.find_repository'
        response = self._call(verb, path)
        if response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        # servers that only support the v1 method don't support external
        # references either.
        self._ensure_real()
        repo = self._real_bzrdir.open_repository()
        response = response + ('no', repo._format.network_name())
        return response, repo

    def _open_repo_v2(self, path):
        verb = 'BzrDir.find_repositoryV2'
        response = self._call(verb, path)
        if response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        self._ensure_real()
        repo = self._real_bzrdir.open_repository()
        response = response + (repo._format.network_name(),)
        return response, repo

    def _open_repo_v3(self, path):
        verb = 'BzrDir.find_repositoryV3'
        medium = self._client._medium
        if medium._is_remote_before((1, 13)):
            raise errors.UnknownSmartMethod(verb)
        try:
            response = self._call(verb, path)
        except errors.UnknownSmartMethod:
            medium._remember_remote_is_before((1, 13))
            raise
        if response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        return response, None

    def open_repository(self):
        path = self._path_for_remote_call(self._client)
        response = None
        for probe in [self._open_repo_v3, self._open_repo_v2,
            self._open_repo_v1]:
            try:
                response, real_repo = probe(path)
                break
            except errors.UnknownSmartMethod:
                pass
        if response is None:
            raise errors.UnknownSmartMethod('BzrDir.find_repository{3,2,}')
        if response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        if len(response) != 6:
            raise SmartProtocolError('incorrect response length %s' % (response,))
        if response[1] == '':
            # repo is at this dir.
            format = response_tuple_to_repo_format(response[2:])
            # Used to support creating a real format instance when needed.
            format._creating_bzrdir = self
            remote_repo = RemoteRepository(self, format)
            format._creating_repo = remote_repo
            if real_repo is not None:
                remote_repo._set_real_repository(real_repo)
            return remote_repo
        else:
            raise errors.NoRepositoryPresent(self)

    def has_workingtree(self):
        if self._has_working_tree is None:
            self._ensure_real()
            self._has_working_tree = self._real_bzrdir.has_workingtree()
        return self._has_working_tree

    def open_workingtree(self, recommend_upgrade=True):
        if self.has_workingtree():
            raise errors.NotLocalUrl(self.root_transport)
        else:
            raise errors.NoWorkingTree(self.root_transport.base)

    def _path_for_remote_call(self, client):
        """Return the path to be used for this bzrdir in a remote call."""
        return client.remote_path_from_transport(self.root_transport)

    def get_branch_transport(self, branch_format, name=None):
        self._ensure_real()
        return self._real_bzrdir.get_branch_transport(branch_format, name=name)

    def get_repository_transport(self, repository_format):
        self._ensure_real()
        return self._real_bzrdir.get_repository_transport(repository_format)

    def get_workingtree_transport(self, workingtree_format):
        self._ensure_real()
        return self._real_bzrdir.get_workingtree_transport(workingtree_format)

    def can_convert_format(self):
        """Upgrading of remote bzrdirs is not supported yet."""
        return False

    def needs_format_conversion(self, format):
        """Upgrading of remote bzrdirs is not supported yet."""
        return False

    def clone(self, url, revision_id=None, force_new_repo=False,
              preserve_stacking=False):
        self._ensure_real()
        return self._real_bzrdir.clone(url, revision_id=revision_id,
            force_new_repo=force_new_repo, preserve_stacking=preserve_stacking)

    def _get_config(self):
        return RemoteBzrDirConfig(self)


class RemoteRepositoryFormat(_mod_repository.RepositoryFormat):
    """Format for repositories accessed over a _SmartClient.

    Instances of this repository are represented by RemoteRepository
    instances.

    The RemoteRepositoryFormat is parameterized during construction
    to reflect the capabilities of the real, remote format. Specifically
    the attributes rich_root_data and supports_tree_reference are set
    on a per instance basis, and are not set (and should not be) at
    the class level.

    :ivar _custom_format: If set, a specific concrete repository format that
        will be used when initializing a repository with this
        RemoteRepositoryFormat.
    :ivar _creating_repo: If set, the repository object that this
        RemoteRepositoryFormat was created for: it can be called into
        to obtain data like the network name.
    """

    _matchingbzrdir = RemoteBzrDirFormat()
    supports_full_versioned_files = True
    supports_leaving_lock = True

    def __init__(self):
        _mod_repository.RepositoryFormat.__init__(self)
        self._custom_format = None
        self._network_name = None
        self._creating_bzrdir = None
        self._supports_chks = None
        self._supports_external_lookups = None
        self._supports_tree_reference = None
        self._supports_funky_characters = None
        self._rich_root_data = None

    def __repr__(self):
        return "%s(_network_name=%r)" % (self.__class__.__name__,
            self._network_name)

    @property
    def fast_deltas(self):
        self._ensure_real()
        return self._custom_format.fast_deltas

    @property
    def rich_root_data(self):
        if self._rich_root_data is None:
            self._ensure_real()
            self._rich_root_data = self._custom_format.rich_root_data
        return self._rich_root_data

    @property
    def supports_chks(self):
        if self._supports_chks is None:
            self._ensure_real()
            self._supports_chks = self._custom_format.supports_chks
        return self._supports_chks

    @property
    def supports_external_lookups(self):
        if self._supports_external_lookups is None:
            self._ensure_real()
            self._supports_external_lookups = \
                self._custom_format.supports_external_lookups
        return self._supports_external_lookups

    @property
    def supports_funky_characters(self):
        if self._supports_funky_characters is None:
            self._ensure_real()
            self._supports_funky_characters = \
                self._custom_format.supports_funky_characters
        return self._supports_funky_characters

    @property
    def supports_tree_reference(self):
        if self._supports_tree_reference is None:
            self._ensure_real()
            self._supports_tree_reference = \
                self._custom_format.supports_tree_reference
        return self._supports_tree_reference

    def _vfs_initialize(self, a_bzrdir, shared):
        """Helper for common code in initialize."""
        if self._custom_format:
            # Custom format requested
            result = self._custom_format.initialize(a_bzrdir, shared=shared)
        elif self._creating_bzrdir is not None:
            # Use the format that the repository we were created to back
            # has.
            prior_repo = self._creating_bzrdir.open_repository()
            prior_repo._ensure_real()
            result = prior_repo._real_repository._format.initialize(
                a_bzrdir, shared=shared)
        else:
            # assume that a_bzr is a RemoteBzrDir but the smart server didn't
            # support remote initialization.
            # We delegate to a real object at this point (as RemoteBzrDir
            # delegate to the repository format which would lead to infinite
            # recursion if we just called a_bzrdir.create_repository.
            a_bzrdir._ensure_real()
            result = a_bzrdir._real_bzrdir.create_repository(shared=shared)
        if not isinstance(result, RemoteRepository):
            return self.open(a_bzrdir)
        else:
            return result

    def initialize(self, a_bzrdir, shared=False):
        # Being asked to create on a non RemoteBzrDir:
        if not isinstance(a_bzrdir, RemoteBzrDir):
            return self._vfs_initialize(a_bzrdir, shared)
        medium = a_bzrdir._client._medium
        if medium._is_remote_before((1, 13)):
            return self._vfs_initialize(a_bzrdir, shared)
        # Creating on a remote bzr dir.
        # 1) get the network name to use.
        if self._custom_format:
            network_name = self._custom_format.network_name()
        elif self._network_name:
            network_name = self._network_name
        else:
            # Select the current bzrlib default and ask for that.
            reference_bzrdir_format = _mod_bzrdir.format_registry.get('default')()
            reference_format = reference_bzrdir_format.repository_format
            network_name = reference_format.network_name()
        # 2) try direct creation via RPC
        path = a_bzrdir._path_for_remote_call(a_bzrdir._client)
        verb = 'BzrDir.create_repository'
        if shared:
            shared_str = 'True'
        else:
            shared_str = 'False'
        try:
            response = a_bzrdir._call(verb, path, network_name, shared_str)
        except errors.UnknownSmartMethod:
            # Fallback - use vfs methods
            medium._remember_remote_is_before((1, 13))
            return self._vfs_initialize(a_bzrdir, shared)
        else:
            # Turn the response into a RemoteRepository object.
            format = response_tuple_to_repo_format(response[1:])
            # Used to support creating a real format instance when needed.
            format._creating_bzrdir = a_bzrdir
            remote_repo = RemoteRepository(a_bzrdir, format)
            format._creating_repo = remote_repo
            return remote_repo

    def open(self, a_bzrdir):
        if not isinstance(a_bzrdir, RemoteBzrDir):
            raise AssertionError('%r is not a RemoteBzrDir' % (a_bzrdir,))
        return a_bzrdir.open_repository()

    def _ensure_real(self):
        if self._custom_format is None:
            self._custom_format = _mod_repository.network_format_registry.get(
                self._network_name)

    @property
    def _fetch_order(self):
        self._ensure_real()
        return self._custom_format._fetch_order

    @property
    def _fetch_uses_deltas(self):
        self._ensure_real()
        return self._custom_format._fetch_uses_deltas

    @property
    def _fetch_reconcile(self):
        self._ensure_real()
        return self._custom_format._fetch_reconcile

    def get_format_description(self):
        self._ensure_real()
        return 'Remote: ' + self._custom_format.get_format_description()

    def __eq__(self, other):
        return self.__class__ is other.__class__

    def network_name(self):
        if self._network_name:
            return self._network_name
        self._creating_repo._ensure_real()
        return self._creating_repo._real_repository._format.network_name()

    @property
    def pack_compresses(self):
        self._ensure_real()
        return self._custom_format.pack_compresses

    @property
    def _serializer(self):
        self._ensure_real()
        return self._custom_format._serializer


class RemoteRepository(_RpcHelper, lock._RelockDebugMixin,
    controldir.ControlComponent):
    """Repository accessed over rpc.

    For the moment most operations are performed using local transport-backed
    Repository objects.
    """

    def __init__(self, remote_bzrdir, format, real_repository=None, _client=None):
        """Create a RemoteRepository instance.

        :param remote_bzrdir: The bzrdir hosting this repository.
        :param format: The RemoteFormat object to use.
        :param real_repository: If not None, a local implementation of the
            repository logic for the repository, usually accessing the data
            via the VFS.
        :param _client: Private testing parameter - override the smart client
            to be used by the repository.
        """
        if real_repository:
            self._real_repository = real_repository
        else:
            self._real_repository = None
        self.bzrdir = remote_bzrdir
        if _client is None:
            self._client = remote_bzrdir._client
        else:
            self._client = _client
        self._format = format
        self._lock_mode = None
        self._lock_token = None
        self._lock_count = 0
        self._leave_lock = False
        # Cache of revision parents; misses are cached during read locks, and
        # write locks when no _real_repository has been set.
        self._unstacked_provider = graph.CachingParentsProvider(
            get_parent_map=self._get_parent_map_rpc)
        self._unstacked_provider.disable_cache()
        # For tests:
        # These depend on the actual remote format, so force them off for
        # maximum compatibility. XXX: In future these should depend on the
        # remote repository instance, but this is irrelevant until we perform
        # reconcile via an RPC call.
        self._reconcile_does_inventory_gc = False
        self._reconcile_fixes_text_parents = False
        self._reconcile_backsup_inventory = False
        self.base = self.bzrdir.transport.base
        # Additional places to query for data.
        self._fallback_repositories = []

    @property
    def user_transport(self):
        return self.bzrdir.user_transport

    @property
    def control_transport(self):
        # XXX: Normally you shouldn't directly get at the remote repository
        # transport, but I'm not sure it's worth making this method
        # optional -- mbp 2010-04-21
        return self.bzrdir.get_repository_transport(None)

    def __str__(self):
        return "%s(%s)" % (self.__class__.__name__, self.base)

    __repr__ = __str__

    def abort_write_group(self, suppress_errors=False):
        """Complete a write group on the decorated repository.

        Smart methods perform operations in a single step so this API
        is not really applicable except as a compatibility thunk
        for older plugins that don't use e.g. the CommitBuilder
        facility.

        :param suppress_errors: see Repository.abort_write_group.
        """
        self._ensure_real()
        return self._real_repository.abort_write_group(
            suppress_errors=suppress_errors)

    @property
    def chk_bytes(self):
        """Decorate the real repository for now.

        In the long term a full blown network facility is needed to avoid
        creating a real repository object locally.
        """
        self._ensure_real()
        return self._real_repository.chk_bytes

    def commit_write_group(self):
        """Complete a write group on the decorated repository.

        Smart methods perform operations in a single step so this API
        is not really applicable except as a compatibility thunk
        for older plugins that don't use e.g. the CommitBuilder
        facility.
        """
        self._ensure_real()
        return self._real_repository.commit_write_group()

    def resume_write_group(self, tokens):
        self._ensure_real()
        return self._real_repository.resume_write_group(tokens)

    def suspend_write_group(self):
        self._ensure_real()
        return self._real_repository.suspend_write_group()

    def get_missing_parent_inventories(self, check_for_missing_texts=True):
        self._ensure_real()
        return self._real_repository.get_missing_parent_inventories(
            check_for_missing_texts=check_for_missing_texts)

    def _get_rev_id_for_revno_vfs(self, revno, known_pair):
        self._ensure_real()
        return self._real_repository.get_rev_id_for_revno(
            revno, known_pair)

    def get_rev_id_for_revno(self, revno, known_pair):
        """See Repository.get_rev_id_for_revno."""
        path = self.bzrdir._path_for_remote_call(self._client)
        try:
            if self._client._medium._is_remote_before((1, 17)):
                return self._get_rev_id_for_revno_vfs(revno, known_pair)
            response = self._call(
                'Repository.get_rev_id_for_revno', path, revno, known_pair)
        except errors.UnknownSmartMethod:
            self._client._medium._remember_remote_is_before((1, 17))
            return self._get_rev_id_for_revno_vfs(revno, known_pair)
        if response[0] == 'ok':
            return True, response[1]
        elif response[0] == 'history-incomplete':
            known_pair = response[1:3]
            for fallback in self._fallback_repositories:
                found, result = fallback.get_rev_id_for_revno(revno, known_pair)
                if found:
                    return True, result
                else:
                    known_pair = result
            # Not found in any fallbacks
            return False, known_pair
        else:
            raise errors.UnexpectedSmartServerResponse(response)

    def _ensure_real(self):
        """Ensure that there is a _real_repository set.

        Used before calls to self._real_repository.

        Note that _ensure_real causes many roundtrips to the server which are
        not desirable, and prevents the use of smart one-roundtrip RPC's to
        perform complex operations (such as accessing parent data, streaming
        revisions etc). Adding calls to _ensure_real should only be done when
        bringing up new functionality, adding fallbacks for smart methods that
        require a fallback path, and never to replace an existing smart method
        invocation. If in doubt chat to the bzr network team.
        """
        if self._real_repository is None:
            if 'hpssvfs' in debug.debug_flags:
                import traceback
                warning('VFS Repository access triggered\n%s',
                    ''.join(traceback.format_stack()))
            self._unstacked_provider.missing_keys.clear()
            self.bzrdir._ensure_real()
            self._set_real_repository(
                self.bzrdir._real_bzrdir.open_repository())

    def _translate_error(self, err, **context):
        self.bzrdir._translate_error(err, repository=self, **context)

    def find_text_key_references(self):
        """Find the text key references within the repository.

        :return: a dictionary mapping (file_id, revision_id) tuples to altered file-ids to an iterable of
        revision_ids. Each altered file-ids has the exact revision_ids that
        altered it listed explicitly.
        :return: A dictionary mapping text keys ((fileid, revision_id) tuples)
            to whether they were referred to by the inventory of the
            revision_id that they contain. The inventory texts from all present
            revision ids are assessed to generate this report.
        """
        self._ensure_real()
        return self._real_repository.find_text_key_references()

    def _generate_text_key_index(self):
        """Generate a new text key index for the repository.

        This is an expensive function that will take considerable time to run.

        :return: A dict mapping (file_id, revision_id) tuples to a list of
            parents, also (file_id, revision_id) tuples.
        """
        self._ensure_real()
        return self._real_repository._generate_text_key_index()

    def _get_revision_graph(self, revision_id):
        """Private method for using with old (< 1.2) servers to fallback."""
        if revision_id is None:
            revision_id = ''
        elif _mod_revision.is_null(revision_id):
            return {}

        path = self.bzrdir._path_for_remote_call(self._client)
        response = self._call_expecting_body(
            'Repository.get_revision_graph', path, revision_id)
        response_tuple, response_handler = response
        if response_tuple[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response_tuple)
        coded = response_handler.read_body_bytes()
        if coded == '':
            # no revisions in this repository!
            return {}
        lines = coded.split('\n')
        revision_graph = {}
        for line in lines:
            d = tuple(line.split())
            revision_graph[d[0]] = d[1:]

        return revision_graph

    def _get_sink(self):
        """See Repository._get_sink()."""
        return RemoteStreamSink(self)

    def _get_source(self, to_format):
        """Return a source for streaming from this repository."""
        return RemoteStreamSource(self, to_format)

    @needs_read_lock
    def has_revision(self, revision_id):
        """True if this repository has a copy of the revision."""
        # Copy of bzrlib.repository.Repository.has_revision
        return revision_id in self.has_revisions((revision_id,))

    @needs_read_lock
    def has_revisions(self, revision_ids):
        """Probe to find out the presence of multiple revisions.

        :param revision_ids: An iterable of revision_ids.
        :return: A set of the revision_ids that were present.
        """
        # Copy of bzrlib.repository.Repository.has_revisions
        parent_map = self.get_parent_map(revision_ids)
        result = set(parent_map)
        if _mod_revision.NULL_REVISION in revision_ids:
            result.add(_mod_revision.NULL_REVISION)
        return result

    def _has_same_fallbacks(self, other_repo):
        """Returns true if the repositories have the same fallbacks."""
        # XXX: copied from Repository; it should be unified into a base class
        # <https://bugs.launchpad.net/bzr/+bug/401622>
        my_fb = self._fallback_repositories
        other_fb = other_repo._fallback_repositories
        if len(my_fb) != len(other_fb):
            return False
        for f, g in zip(my_fb, other_fb):
            if not f.has_same_location(g):
                return False
        return True

    def has_same_location(self, other):
        # TODO: Move to RepositoryBase and unify with the regular Repository
        # one; unfortunately the tests rely on slightly different behaviour at
        # present -- mbp 20090710
        return (self.__class__ is other.__class__ and
                self.bzrdir.transport.base == other.bzrdir.transport.base)

    def get_graph(self, other_repository=None):
        """Return the graph for this repository format"""
        parents_provider = self._make_parents_provider(other_repository)
        return graph.Graph(parents_provider)

    @needs_read_lock
    def get_known_graph_ancestry(self, revision_ids):
        """Return the known graph for a set of revision ids and their ancestors.
        """
        st = static_tuple.StaticTuple
        revision_keys = [st(r_id).intern() for r_id in revision_ids]
        known_graph = self.revisions.get_known_graph_ancestry(revision_keys)
        return graph.GraphThunkIdsToKeys(known_graph)

    def gather_stats(self, revid=None, committers=None):
        """See Repository.gather_stats()."""
        path = self.bzrdir._path_for_remote_call(self._client)
        # revid can be None to indicate no revisions, not just NULL_REVISION
        if revid is None or _mod_revision.is_null(revid):
            fmt_revid = ''
        else:
            fmt_revid = revid
        if committers is None or not committers:
            fmt_committers = 'no'
        else:
            fmt_committers = 'yes'
        response_tuple, response_handler = self._call_expecting_body(
            'Repository.gather_stats', path, fmt_revid, fmt_committers)
        if response_tuple[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response_tuple)

        body = response_handler.read_body_bytes()
        result = {}
        for line in body.split('\n'):
            if not line:
                continue
            key, val_text = line.split(':')
            if key in ('revisions', 'size', 'committers'):
                result[key] = int(val_text)
            elif key in ('firstrev', 'latestrev'):
                values = val_text.split(' ')[1:]
                result[key] = (float(values[0]), long(values[1]))

        return result

    def find_branches(self, using=False):
        """See Repository.find_branches()."""
        # should be an API call to the server.
        self._ensure_real()
        return self._real_repository.find_branches(using=using)

    def get_physical_lock_status(self):
        """See Repository.get_physical_lock_status()."""
        # should be an API call to the server.
        self._ensure_real()
        return self._real_repository.get_physical_lock_status()

    def is_in_write_group(self):
        """Return True if there is an open write group.

        write groups are only applicable locally for the smart server..
        """
        if self._real_repository:
            return self._real_repository.is_in_write_group()

    def is_locked(self):
        return self._lock_count >= 1

    def is_shared(self):
        """See Repository.is_shared()."""
        path = self.bzrdir._path_for_remote_call(self._client)
        response = self._call('Repository.is_shared', path)
        if response[0] not in ('yes', 'no'):
            raise SmartProtocolError('unexpected response code %s' % (response,))
        return response[0] == 'yes'

    def is_write_locked(self):
        return self._lock_mode == 'w'

    def _warn_if_deprecated(self, branch=None):
        # If we have a real repository, the check will be done there, if we
        # don't the check will be done remotely.
        pass

    def lock_read(self):
        """Lock the repository for read operations.

        :return: A bzrlib.lock.LogicalLockResult.
        """
        # wrong eventually - want a local lock cache context
        if not self._lock_mode:
            self._note_lock('r')
            self._lock_mode = 'r'
            self._lock_count = 1
            self._unstacked_provider.enable_cache(cache_misses=True)
            if self._real_repository is not None:
                self._real_repository.lock_read()
            for repo in self._fallback_repositories:
                repo.lock_read()
        else:
            self._lock_count += 1
        return lock.LogicalLockResult(self.unlock)

    def _remote_lock_write(self, token):
        path = self.bzrdir._path_for_remote_call(self._client)
        if token is None:
            token = ''
        err_context = {'token': token}
        response = self._call('Repository.lock_write', path, token,
                              **err_context)
        if response[0] == 'ok':
            ok, token = response
            return token
        else:
            raise errors.UnexpectedSmartServerResponse(response)

    def lock_write(self, token=None, _skip_rpc=False):
        if not self._lock_mode:
            self._note_lock('w')
            if _skip_rpc:
                if self._lock_token is not None:
                    if token != self._lock_token:
                        raise errors.TokenMismatch(token, self._lock_token)
                self._lock_token = token
            else:
                self._lock_token = self._remote_lock_write(token)
            # if self._lock_token is None, then this is something like packs or
            # svn where we don't get to lock the repo, or a weave style repository
            # where we cannot lock it over the wire and attempts to do so will
            # fail.
            if self._real_repository is not None:
                self._real_repository.lock_write(token=self._lock_token)
            if token is not None:
                self._leave_lock = True
            else:
                self._leave_lock = False
            self._lock_mode = 'w'
            self._lock_count = 1
            cache_misses = self._real_repository is None
            self._unstacked_provider.enable_cache(cache_misses=cache_misses)
            for repo in self._fallback_repositories:
                # Writes don't affect fallback repos
                repo.lock_read()
        elif self._lock_mode == 'r':
            raise errors.ReadOnlyError(self)
        else:
            self._lock_count += 1
        return RepositoryWriteLockResult(self.unlock, self._lock_token or None)

    def leave_lock_in_place(self):
        if not self._lock_token:
            raise NotImplementedError(self.leave_lock_in_place)
        self._leave_lock = True

    def dont_leave_lock_in_place(self):
        if not self._lock_token:
            raise NotImplementedError(self.dont_leave_lock_in_place)
        self._leave_lock = False

    def _set_real_repository(self, repository):
        """Set the _real_repository for this repository.

        :param repository: The repository to fallback to for non-hpss
            implemented operations.
        """
        if self._real_repository is not None:
            # Replacing an already set real repository.
            # We cannot do this [currently] if the repository is locked -
            # synchronised state might be lost.
            if self.is_locked():
                raise AssertionError('_real_repository is already set')
        if isinstance(repository, RemoteRepository):
            raise AssertionError()
        self._real_repository = repository
        # three code paths happen here:
        # 1) old servers, RemoteBranch.open() calls _ensure_real before setting
        # up stacking. In this case self._fallback_repositories is [], and the
        # real repo is already setup. Preserve the real repo and
        # RemoteRepository.add_fallback_repository will avoid adding
        # duplicates.
        # 2) new servers, RemoteBranch.open() sets up stacking, and when
        # ensure_real is triggered from a branch, the real repository to
        # set already has a matching list with separate instances, but
        # as they are also RemoteRepositories we don't worry about making the
        # lists be identical.
        # 3) new servers, RemoteRepository.ensure_real is triggered before
        # RemoteBranch.ensure real, in this case we get a repo with no fallbacks
        # and need to populate it.
        if (self._fallback_repositories and
            len(self._real_repository._fallback_repositories) !=
            len(self._fallback_repositories)):
            if len(self._real_repository._fallback_repositories):
                raise AssertionError(
                    "cannot cleanly remove existing _fallback_repositories")
        for fb in self._fallback_repositories:
            self._real_repository.add_fallback_repository(fb)
        if self._lock_mode == 'w':
            # if we are already locked, the real repository must be able to
            # acquire the lock with our token.
            self._real_repository.lock_write(self._lock_token)
        elif self._lock_mode == 'r':
            self._real_repository.lock_read()

    def start_write_group(self):
        """Start a write group on the decorated repository.

        Smart methods perform operations in a single step so this API
        is not really applicable except as a compatibility thunk
        for older plugins that don't use e.g. the CommitBuilder
        facility.
        """
        self._ensure_real()
        return self._real_repository.start_write_group()

    def _unlock(self, token):
        path = self.bzrdir._path_for_remote_call(self._client)
        if not token:
            # with no token the remote repository is not persistently locked.
            return
        err_context = {'token': token}
        response = self._call('Repository.unlock', path, token,
                              **err_context)
        if response == ('ok',):
            return
        else:
            raise errors.UnexpectedSmartServerResponse(response)

    @only_raises(errors.LockNotHeld, errors.LockBroken)
    def unlock(self):
        if not self._lock_count:
            return lock.cant_unlock_not_held(self)
        self._lock_count -= 1
        if self._lock_count > 0:
            return
        self._unstacked_provider.disable_cache()
        old_mode = self._lock_mode
        self._lock_mode = None
        try:
            # The real repository is responsible at present for raising an
            # exception if it's in an unfinished write group.  However, it
            # normally will *not* actually remove the lock from disk - that's
            # done by the server on receiving the Repository.unlock call.
            # This is just to let the _real_repository stay up to date.
            if self._real_repository is not None:
                self._real_repository.unlock()
        finally:
            # The rpc-level lock should be released even if there was a
            # problem releasing the vfs-based lock.
            if old_mode == 'w':
                # Only write-locked repositories need to make a remote method
                # call to perform the unlock.
                old_token = self._lock_token
                self._lock_token = None
                if not self._leave_lock:
                    self._unlock(old_token)
        # Fallbacks are always 'lock_read()' so we don't pay attention to
        # self._leave_lock
        for repo in self._fallback_repositories:
            repo.unlock()

    def break_lock(self):
        # should hand off to the network
        self._ensure_real()
        return self._real_repository.break_lock()

    def _get_tarball(self, compression):
        """Return a TemporaryFile containing a repository tarball.

        Returns None if the server does not support sending tarballs.
        """
        import tempfile
        path = self.bzrdir._path_for_remote_call(self._client)
        try:
            response, protocol = self._call_expecting_body(
                'Repository.tarball', path, compression)
        except errors.UnknownSmartMethod:
            protocol.cancel_read_body()
            return None
        if response[0] == 'ok':
            # Extract the tarball and return it
            t = tempfile.NamedTemporaryFile()
            # TODO: rpc layer should read directly into it...
            t.write(protocol.read_body_bytes())
            t.seek(0)
            return t
        raise errors.UnexpectedSmartServerResponse(response)

    def sprout(self, to_bzrdir, revision_id=None):
        # TODO: Option to control what format is created?
        self._ensure_real()
        dest_repo = self._real_repository._format.initialize(to_bzrdir,
                                                             shared=False)
        dest_repo.fetch(self, revision_id=revision_id)
        return dest_repo

    ### These methods are just thin shims to the VFS object for now.

    def revision_tree(self, revision_id):
        self._ensure_real()
        return self._real_repository.revision_tree(revision_id)

    def get_serializer_format(self):
        self._ensure_real()
        return self._real_repository.get_serializer_format()

    def get_commit_builder(self, branch, parents, config, timestamp=None,
                           timezone=None, committer=None, revprops=None,
                           revision_id=None):
        # FIXME: It ought to be possible to call this without immediately
        # triggering _ensure_real.  For now it's the easiest thing to do.
        self._ensure_real()
        real_repo = self._real_repository
        builder = real_repo.get_commit_builder(branch, parents,
                config, timestamp=timestamp, timezone=timezone,
                committer=committer, revprops=revprops, revision_id=revision_id)
        return builder

    def add_fallback_repository(self, repository):
        """Add a repository to use for looking up data not held locally.

        :param repository: A repository.
        """
        if not self._format.supports_external_lookups:
            raise errors.UnstackableRepositoryFormat(
                self._format.network_name(), self.base)
        # We need to accumulate additional repositories here, to pass them in
        # on various RPC's.
        #
        if self.is_locked():
            # We will call fallback.unlock() when we transition to the unlocked
            # state, so always add a lock here. If a caller passes us a locked
            # repository, they are responsible for unlocking it later.
            repository.lock_read()
        self._check_fallback_repository(repository)
        self._fallback_repositories.append(repository)
        # If self._real_repository was parameterised already (e.g. because a
        # _real_branch had its get_stacked_on_url method called), then the
        # repository to be added may already be in the _real_repositories list.
        if self._real_repository is not None:
            fallback_locations = [repo.user_url for repo in
                self._real_repository._fallback_repositories]
            if repository.user_url not in fallback_locations:
                self._real_repository.add_fallback_repository(repository)

    def _check_fallback_repository(self, repository):
        """Check that this repository can fallback to repository safely.

        Raise an error if not.

        :param repository: A repository to fallback to.
        """
        return _mod_repository.InterRepository._assert_same_model(
            self, repository)

    def add_inventory(self, revid, inv, parents):
        self._ensure_real()
        return self._real_repository.add_inventory(revid, inv, parents)

    def add_inventory_by_delta(self, basis_revision_id, delta, new_revision_id,
            parents, basis_inv=None, propagate_caches=False):
        self._ensure_real()
        return self._real_repository.add_inventory_by_delta(basis_revision_id,
            delta, new_revision_id, parents, basis_inv=basis_inv,
            propagate_caches=propagate_caches)

    def add_revision(self, rev_id, rev, inv=None, config=None):
        self._ensure_real()
        return self._real_repository.add_revision(
            rev_id, rev, inv=inv, config=config)

    @needs_read_lock
    def get_inventory(self, revision_id):
        self._ensure_real()
        return self._real_repository.get_inventory(revision_id)

    def iter_inventories(self, revision_ids, ordering=None):
        self._ensure_real()
        return self._real_repository.iter_inventories(revision_ids, ordering)

    @needs_read_lock
    def get_revision(self, revision_id):
        self._ensure_real()
        return self._real_repository.get_revision(revision_id)

    def get_transaction(self):
        self._ensure_real()
        return self._real_repository.get_transaction()

    @needs_read_lock
    def clone(self, a_bzrdir, revision_id=None):
        self._ensure_real()
        return self._real_repository.clone(a_bzrdir, revision_id=revision_id)

    def make_working_trees(self):
        """See Repository.make_working_trees"""
        self._ensure_real()
        return self._real_repository.make_working_trees()

    def refresh_data(self):
        """Re-read any data needed to synchronise with disk.

        This method is intended to be called after another repository instance
        (such as one used by a smart server) has inserted data into the
        repository. On all repositories this will work outside of write groups.
        Some repository formats (pack and newer for bzrlib native formats)
        support refresh_data inside write groups. If called inside a write
        group on a repository that does not support refreshing in a write group
        IsInWriteGroupError will be raised.
        """
        if self._real_repository is not None:
            self._real_repository.refresh_data()

    def revision_ids_to_search_result(self, result_set):
        """Convert a set of revision ids to a graph SearchResult."""
        result_parents = set()
        for parents in self.get_graph().get_parent_map(
            result_set).itervalues():
            result_parents.update(parents)
        included_keys = result_set.intersection(result_parents)
        start_keys = result_set.difference(included_keys)
        exclude_keys = result_parents.difference(result_set)
        result = graph.SearchResult(start_keys, exclude_keys,
            len(result_set), result_set)
        return result

    @needs_read_lock
    def search_missing_revision_ids(self, other,
            revision_id=symbol_versioning.DEPRECATED_PARAMETER,
            find_ghosts=True, revision_ids=None, if_present_ids=None):
        """Return the revision ids that other has that this does not.

        These are returned in topological order.

        revision_id: only return revision ids included by revision_id.
        """
        if symbol_versioning.deprecated_passed(revision_id):
            symbol_versioning.warn(
                'search_missing_revision_ids(revision_id=...) was '
                'deprecated in 2.4.  Use revision_ids=[...] instead.',
                DeprecationWarning, stacklevel=2)
            if revision_ids is not None:
                raise AssertionError(
                    'revision_ids is mutually exclusive with revision_id')
            if revision_id is not None:
                revision_ids = [revision_id]
        inter_repo = _mod_repository.InterRepository.get(other, self)
        return inter_repo.search_missing_revision_ids(
            find_ghosts=find_ghosts, revision_ids=revision_ids,
            if_present_ids=if_present_ids)

    def fetch(self, source, revision_id=None, find_ghosts=False,
            fetch_spec=None):
        # No base implementation to use as RemoteRepository is not a subclass
        # of Repository; so this is a copy of Repository.fetch().
        if fetch_spec is not None and revision_id is not None:
            raise AssertionError(
                "fetch_spec and revision_id are mutually exclusive.")
        if self.is_in_write_group():
            raise errors.InternalBzrError(
                "May not fetch while in a write group.")
        # fast path same-url fetch operations
        if (self.has_same_location(source)
            and fetch_spec is None
            and self._has_same_fallbacks(source)):
            # check that last_revision is in 'from' and then return a
            # no-operation.
            if (revision_id is not None and
                not _mod_revision.is_null(revision_id)):
                self.get_revision(revision_id)
            return 0, []
        # if there is no specific appropriate InterRepository, this will get
        # the InterRepository base class, which raises an
        # IncompatibleRepositories when asked to fetch.
        inter = _mod_repository.InterRepository.get(source, self)
        return inter.fetch(revision_id=revision_id,
            find_ghosts=find_ghosts, fetch_spec=fetch_spec)

    def create_bundle(self, target, base, fileobj, format=None):
        self._ensure_real()
        self._real_repository.create_bundle(target, base, fileobj, format)

    @needs_read_lock
    def get_ancestry(self, revision_id, topo_sorted=True):
        self._ensure_real()
        return self._real_repository.get_ancestry(revision_id, topo_sorted)

    def fileids_altered_by_revision_ids(self, revision_ids):
        self._ensure_real()
        return self._real_repository.fileids_altered_by_revision_ids(revision_ids)

    def _get_versioned_file_checker(self, revisions, revision_versions_cache):
        self._ensure_real()
        return self._real_repository._get_versioned_file_checker(
            revisions, revision_versions_cache)

    def iter_files_bytes(self, desired_files):
        """See Repository.iter_file_bytes.
        """
        self._ensure_real()
        return self._real_repository.iter_files_bytes(desired_files)

    def get_parent_map(self, revision_ids):
        """See bzrlib.Graph.get_parent_map()."""
        return self._make_parents_provider().get_parent_map(revision_ids)

    def _get_parent_map_rpc(self, keys):
        """Helper for get_parent_map that performs the RPC."""
        medium = self._client._medium
        if medium._is_remote_before((1, 2)):
            # We already found out that the server can't understand
            # Repository.get_parent_map requests, so just fetch the whole
            # graph.
            #
            # Note that this reads the whole graph, when only some keys are
            # wanted.  On this old server there's no way (?) to get them all
            # in one go, and the user probably will have seen a warning about
            # the server being old anyhow.
            rg = self._get_revision_graph(None)
            # There is an API discrepancy between get_parent_map and
            # get_revision_graph. Specifically, a "key:()" pair in
            # get_revision_graph just means a node has no parents. For
            # "get_parent_map" it means the node is a ghost. So fix up the
            # graph to correct this.
            #   https://bugs.launchpad.net/bzr/+bug/214894
            # There is one other "bug" which is that ghosts in
            # get_revision_graph() are not returned at all. But we won't worry
            # about that for now.
            for node_id, parent_ids in rg.iteritems():
                if parent_ids == ():
                    rg[node_id] = (NULL_REVISION,)
            rg[NULL_REVISION] = ()
            return rg

        keys = set(keys)
        if None in keys:
            raise ValueError('get_parent_map(None) is not valid')
        if NULL_REVISION in keys:
            keys.discard(NULL_REVISION)
            found_parents = {NULL_REVISION:()}
            if not keys:
                return found_parents
        else:
            found_parents = {}
        # TODO(Needs analysis): We could assume that the keys being requested
        # from get_parent_map are in a breadth first search, so typically they
        # will all be depth N from some common parent, and we don't have to
        # have the server iterate from the root parent, but rather from the
        # keys we're searching; and just tell the server the keyspace we
        # already have; but this may be more traffic again.

        # Transform self._parents_map into a search request recipe.
        # TODO: Manage this incrementally to avoid covering the same path
        # repeatedly. (The server will have to on each request, but the less
        # work done the better).
        #
        # Negative caching notes:
        # new server sends missing when a request including the revid
        # 'include-missing:' is present in the request.
        # missing keys are serialised as missing:X, and we then call
        # provider.note_missing(X) for-all X
        parents_map = self._unstacked_provider.get_cached_map()
        if parents_map is None:
            # Repository is not locked, so there's no cache.
            parents_map = {}
        # start_set is all the keys in the cache
        start_set = set(parents_map)
        # result set is all the references to keys in the cache
        result_parents = set()
        for parents in parents_map.itervalues():
            result_parents.update(parents)
        stop_keys = result_parents.difference(start_set)
        # We don't need to send ghosts back to the server as a position to
        # stop either.
        stop_keys.difference_update(self._unstacked_provider.missing_keys)
        key_count = len(parents_map)
        if (NULL_REVISION in result_parents
            and NULL_REVISION in self._unstacked_provider.missing_keys):
            # If we pruned NULL_REVISION from the stop_keys because it's also
            # in our cache of "missing" keys we need to increment our key count
            # by 1, because the reconsitituted SearchResult on the server will
            # still consider NULL_REVISION to be an included key.
            key_count += 1
        included_keys = start_set.intersection(result_parents)
        start_set.difference_update(included_keys)
        recipe = ('manual', start_set, stop_keys, key_count)
        body = self._serialise_search_recipe(recipe)
        path = self.bzrdir._path_for_remote_call(self._client)
        for key in keys:
            if type(key) is not str:
                raise ValueError(
                    "key %r not a plain string" % (key,))
        verb = 'Repository.get_parent_map'
        args = (path, 'include-missing:') + tuple(keys)
        try:
            response = self._call_with_body_bytes_expecting_body(
                verb, args, body)
        except errors.UnknownSmartMethod:
            # Server does not support this method, so get the whole graph.
            # Worse, we have to force a disconnection, because the server now
            # doesn't realise it has a body on the wire to consume, so the
            # only way to recover is to abandon the connection.
            warning(
                'Server is too old for fast get_parent_map, reconnecting.  '
                '(Upgrade the server to Bazaar 1.2 to avoid this)')
            medium.disconnect()
            # To avoid having to disconnect repeatedly, we keep track of the
            # fact the server doesn't understand remote methods added in 1.2.
            medium._remember_remote_is_before((1, 2))
            # Recurse just once and we should use the fallback code.
            return self._get_parent_map_rpc(keys)
        response_tuple, response_handler = response
        if response_tuple[0] not in ['ok']:
            response_handler.cancel_read_body()
            raise errors.UnexpectedSmartServerResponse(response_tuple)
        if response_tuple[0] == 'ok':
            coded = bz2.decompress(response_handler.read_body_bytes())
            if coded == '':
                # no revisions found
                return {}
            lines = coded.split('\n')
            revision_graph = {}
            for line in lines:
                d = tuple(line.split())
                if len(d) > 1:
                    revision_graph[d[0]] = d[1:]
                else:
                    # No parents:
                    if d[0].startswith('missing:'):
                        revid = d[0][8:]
                        self._unstacked_provider.note_missing_key(revid)
                    else:
                        # no parents - so give the Graph result
                        # (NULL_REVISION,).
                        revision_graph[d[0]] = (NULL_REVISION,)
            return revision_graph

    @needs_read_lock
    def get_signature_text(self, revision_id):
        self._ensure_real()
        return self._real_repository.get_signature_text(revision_id)

    @needs_read_lock
    def _get_inventory_xml(self, revision_id):
        self._ensure_real()
        return self._real_repository._get_inventory_xml(revision_id)

    def reconcile(self, other=None, thorough=False):
        self._ensure_real()
        return self._real_repository.reconcile(other=other, thorough=thorough)

    def all_revision_ids(self):
        self._ensure_real()
        return self._real_repository.all_revision_ids()

    @needs_read_lock
    def get_deltas_for_revisions(self, revisions, specific_fileids=None):
        self._ensure_real()
        return self._real_repository.get_deltas_for_revisions(revisions,
            specific_fileids=specific_fileids)

    @needs_read_lock
    def get_revision_delta(self, revision_id, specific_fileids=None):
        self._ensure_real()
        return self._real_repository.get_revision_delta(revision_id,
            specific_fileids=specific_fileids)

    @needs_read_lock
    def revision_trees(self, revision_ids):
        self._ensure_real()
        return self._real_repository.revision_trees(revision_ids)

    @needs_read_lock
    def get_revision_reconcile(self, revision_id):
        self._ensure_real()
        return self._real_repository.get_revision_reconcile(revision_id)

    @needs_read_lock
    def check(self, revision_ids=None, callback_refs=None, check_repo=True):
        self._ensure_real()
        return self._real_repository.check(revision_ids=revision_ids,
            callback_refs=callback_refs, check_repo=check_repo)

    def copy_content_into(self, destination, revision_id=None):
        self._ensure_real()
        return self._real_repository.copy_content_into(
            destination, revision_id=revision_id)

    def _copy_repository_tarball(self, to_bzrdir, revision_id=None):
        # get a tarball of the remote repository, and copy from that into the
        # destination
        from bzrlib import osutils
        import tarfile
        # TODO: Maybe a progress bar while streaming the tarball?
        note("Copying repository content as tarball...")
        tar_file = self._get_tarball('bz2')
        if tar_file is None:
            return None
        destination = to_bzrdir.create_repository()
        try:
            tar = tarfile.open('repository', fileobj=tar_file,
                mode='r|bz2')
            tmpdir = osutils.mkdtemp()
            try:
                _extract_tar(tar, tmpdir)
                tmp_bzrdir = _mod_bzrdir.BzrDir.open(tmpdir)
                tmp_repo = tmp_bzrdir.open_repository()
                tmp_repo.copy_content_into(destination, revision_id)
            finally:
                osutils.rmtree(tmpdir)
        finally:
            tar_file.close()
        return destination
        # TODO: Suggestion from john: using external tar is much faster than
        # python's tarfile library, but it may not work on windows.

    @property
    def inventories(self):
        """Decorate the real repository for now.

        In the long term a full blown network facility is needed to
        avoid creating a real repository object locally.
        """
        self._ensure_real()
        return self._real_repository.inventories

    @needs_write_lock
    def pack(self, hint=None, clean_obsolete_packs=False):
        """Compress the data within the repository.

        This is not currently implemented within the smart server.
        """
        self._ensure_real()
        return self._real_repository.pack(hint=hint, clean_obsolete_packs=clean_obsolete_packs)

    @property
    def revisions(self):
        """Decorate the real repository for now.

        In the short term this should become a real object to intercept graph
        lookups.

        In the long term a full blown network facility is needed.
        """
        self._ensure_real()
        return self._real_repository.revisions

    def set_make_working_trees(self, new_value):
        if new_value:
            new_value_str = "True"
        else:
            new_value_str = "False"
        path = self.bzrdir._path_for_remote_call(self._client)
        try:
            response = self._call(
                'Repository.set_make_working_trees', path, new_value_str)
        except errors.UnknownSmartMethod:
            self._ensure_real()
            self._real_repository.set_make_working_trees(new_value)
        else:
            if response[0] != 'ok':
                raise errors.UnexpectedSmartServerResponse(response)

    @property
    def signatures(self):
        """Decorate the real repository for now.

        In the long term a full blown network facility is needed to avoid
        creating a real repository object locally.
        """
        self._ensure_real()
        return self._real_repository.signatures

    @needs_write_lock
    def sign_revision(self, revision_id, gpg_strategy):
        self._ensure_real()
        return self._real_repository.sign_revision(revision_id, gpg_strategy)

    @property
    def texts(self):
        """Decorate the real repository for now.

        In the long term a full blown network facility is needed to avoid
        creating a real repository object locally.
        """
        self._ensure_real()
        return self._real_repository.texts

    @needs_read_lock
    def get_revisions(self, revision_ids):
        self._ensure_real()
        return self._real_repository.get_revisions(revision_ids)

    def supports_rich_root(self):
        return self._format.rich_root_data

    def iter_reverse_revision_history(self, revision_id):
        self._ensure_real()
        return self._real_repository.iter_reverse_revision_history(revision_id)

    @property
    def _serializer(self):
        return self._format._serializer

    def store_revision_signature(self, gpg_strategy, plaintext, revision_id):
        self._ensure_real()
        return self._real_repository.store_revision_signature(
            gpg_strategy, plaintext, revision_id)

    def add_signature_text(self, revision_id, signature):
        self._ensure_real()
        return self._real_repository.add_signature_text(revision_id, signature)

    def has_signature_for_revision_id(self, revision_id):
        self._ensure_real()
        return self._real_repository.has_signature_for_revision_id(revision_id)

    def item_keys_introduced_by(self, revision_ids, _files_pb=None):
        self._ensure_real()
        return self._real_repository.item_keys_introduced_by(revision_ids,
            _files_pb=_files_pb)

    def revision_graph_can_have_wrong_parents(self):
        # The answer depends on the remote repo format.
        self._ensure_real()
        return self._real_repository.revision_graph_can_have_wrong_parents()

    def _find_inconsistent_revision_parents(self, revisions_iterator=None):
        self._ensure_real()
        return self._real_repository._find_inconsistent_revision_parents(
            revisions_iterator)

    def _check_for_inconsistent_revision_parents(self):
        self._ensure_real()
        return self._real_repository._check_for_inconsistent_revision_parents()

    def _make_parents_provider(self, other=None):
        providers = [self._unstacked_provider]
        if other is not None:
            providers.insert(0, other)
        providers.extend(r._make_parents_provider() for r in
                         self._fallback_repositories)
        return graph.StackedParentsProvider(providers)

    def _serialise_search_recipe(self, recipe):
        """Serialise a graph search recipe.

        :param recipe: A search recipe (start, stop, count).
        :return: Serialised bytes.
        """
        start_keys = ' '.join(recipe[1])
        stop_keys = ' '.join(recipe[2])
        count = str(recipe[3])
        return '\n'.join((start_keys, stop_keys, count))

    def _serialise_search_result(self, search_result):
        parts = search_result.get_network_struct()
        return '\n'.join(parts)

    def autopack(self):
        path = self.bzrdir._path_for_remote_call(self._client)
        try:
            response = self._call('PackRepository.autopack', path)
        except errors.UnknownSmartMethod:
            self._ensure_real()
            self._real_repository._pack_collection.autopack()
            return
        self.refresh_data()
        if response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)


class RemoteStreamSink(_mod_repository.StreamSink):

    def _insert_real(self, stream, src_format, resume_tokens):
        self.target_repo._ensure_real()
        sink = self.target_repo._real_repository._get_sink()
        result = sink.insert_stream(stream, src_format, resume_tokens)
        if not result:
            self.target_repo.autopack()
        return result

    def insert_stream(self, stream, src_format, resume_tokens):
        target = self.target_repo
        target._unstacked_provider.missing_keys.clear()
        candidate_calls = [('Repository.insert_stream_1.19', (1, 19))]
        if target._lock_token:
            candidate_calls.append(('Repository.insert_stream_locked', (1, 14)))
            lock_args = (target._lock_token or '',)
        else:
            candidate_calls.append(('Repository.insert_stream', (1, 13)))
            lock_args = ()
        client = target._client
        medium = client._medium
        path = target.bzrdir._path_for_remote_call(client)
        # Probe for the verb to use with an empty stream before sending the
        # real stream to it.  We do this both to avoid the risk of sending a
        # large request that is then rejected, and because we don't want to
        # implement a way to buffer, rewind, or restart the stream.
        found_verb = False
        for verb, required_version in candidate_calls:
            if medium._is_remote_before(required_version):
                continue
            if resume_tokens:
                # We've already done the probing (and set _is_remote_before) on
                # a previous insert.
                found_verb = True
                break
            byte_stream = smart_repo._stream_to_byte_stream([], src_format)
            try:
                response = client.call_with_body_stream(
                    (verb, path, '') + lock_args, byte_stream)
            except errors.UnknownSmartMethod:
                medium._remember_remote_is_before(required_version)
            else:
                found_verb = True
                break
        if not found_verb:
            # Have to use VFS.
            return self._insert_real(stream, src_format, resume_tokens)
        self._last_inv_record = None
        self._last_substream = None
        if required_version < (1, 19):
            # Remote side doesn't support inventory deltas.  Wrap the stream to
            # make sure we don't send any.  If the stream contains inventory
            # deltas we'll interrupt the smart insert_stream request and
            # fallback to VFS.
            stream = self._stop_stream_if_inventory_delta(stream)
        byte_stream = smart_repo._stream_to_byte_stream(
            stream, src_format)
        resume_tokens = ' '.join(resume_tokens)
        response = client.call_with_body_stream(
            (verb, path, resume_tokens) + lock_args, byte_stream)
        if response[0][0] not in ('ok', 'missing-basis'):
            raise errors.UnexpectedSmartServerResponse(response)
        if self._last_substream is not None:
            # The stream included an inventory-delta record, but the remote
            # side isn't new enough to support them.  So we need to send the
            # rest of the stream via VFS.
            self.target_repo.refresh_data()
            return self._resume_stream_with_vfs(response, src_format)
        if response[0][0] == 'missing-basis':
            tokens, missing_keys = bencode.bdecode_as_tuple(response[0][1])
            resume_tokens = tokens
            return resume_tokens, set(missing_keys)
        else:
            self.target_repo.refresh_data()
            return [], set()

    def _resume_stream_with_vfs(self, response, src_format):
        """Resume sending a stream via VFS, first resending the record and
        substream that couldn't be sent via an insert_stream verb.
        """
        if response[0][0] == 'missing-basis':
            tokens, missing_keys = bencode.bdecode_as_tuple(response[0][1])
            # Ignore missing_keys, we haven't finished inserting yet
        else:
            tokens = []
        def resume_substream():
            # Yield the substream that was interrupted.
            for record in self._last_substream:
                yield record
            self._last_substream = None
        def resume_stream():
            # Finish sending the interrupted substream
            yield ('inventory-deltas', resume_substream())
            # Then simply continue sending the rest of the stream.
            for substream_kind, substream in self._last_stream:
                yield substream_kind, substream
        return self._insert_real(resume_stream(), src_format, tokens)

    def _stop_stream_if_inventory_delta(self, stream):
        """Normally this just lets the original stream pass-through unchanged.

        However if any 'inventory-deltas' substream occurs it will stop
        streaming, and store the interrupted substream and stream in
        self._last_substream and self._last_stream so that the stream can be
        resumed by _resume_stream_with_vfs.
        """

        stream_iter = iter(stream)
        for substream_kind, substream in stream_iter:
            if substream_kind == 'inventory-deltas':
                self._last_substream = substream
                self._last_stream = stream_iter
                return
            else:
                yield substream_kind, substream


class RemoteStreamSource(_mod_repository.StreamSource):
    """Stream data from a remote server."""

    def get_stream(self, search):
        if (self.from_repository._fallback_repositories and
            self.to_format._fetch_order == 'topological'):
            return self._real_stream(self.from_repository, search)
        sources = []
        seen = set()
        repos = [self.from_repository]
        while repos:
            repo = repos.pop(0)
            if repo in seen:
                continue
            seen.add(repo)
            repos.extend(repo._fallback_repositories)
            sources.append(repo)
        return self.missing_parents_chain(search, sources)

    def get_stream_for_missing_keys(self, missing_keys):
        self.from_repository._ensure_real()
        real_repo = self.from_repository._real_repository
        real_source = real_repo._get_source(self.to_format)
        return real_source.get_stream_for_missing_keys(missing_keys)

    def _real_stream(self, repo, search):
        """Get a stream for search from repo.
        
        This never called RemoteStreamSource.get_stream, and is a heler
        for RemoteStreamSource._get_stream to allow getting a stream 
        reliably whether fallback back because of old servers or trying
        to stream from a non-RemoteRepository (which the stacked support
        code will do).
        """
        source = repo._get_source(self.to_format)
        if isinstance(source, RemoteStreamSource):
            repo._ensure_real()
            source = repo._real_repository._get_source(self.to_format)
        return source.get_stream(search)

    def _get_stream(self, repo, search):
        """Core worker to get a stream from repo for search.

        This is used by both get_stream and the stacking support logic. It
        deliberately gets a stream for repo which does not need to be
        self.from_repository. In the event that repo is not Remote, or
        cannot do a smart stream, a fallback is made to the generic
        repository._get_stream() interface, via self._real_stream.

        In the event of stacking, streams from _get_stream will not
        contain all the data for search - this is normal (see get_stream).

        :param repo: A repository.
        :param search: A search.
        """
        # Fallbacks may be non-smart
        if not isinstance(repo, RemoteRepository):
            return self._real_stream(repo, search)
        client = repo._client
        medium = client._medium
        path = repo.bzrdir._path_for_remote_call(client)
        search_bytes = repo._serialise_search_result(search)
        args = (path, self.to_format.network_name())
        candidate_verbs = [
            ('Repository.get_stream_1.19', (1, 19)),
            ('Repository.get_stream', (1, 13))]

        found_verb = False
        for verb, version in candidate_verbs:
            if medium._is_remote_before(version):
                continue
            try:
                response = repo._call_with_body_bytes_expecting_body(
                    verb, args, search_bytes)
            except errors.UnknownSmartMethod:
                medium._remember_remote_is_before(version)
            except errors.UnknownErrorFromSmartServer, e:
                if isinstance(search, graph.EverythingResult):
                    error_verb = e.error_from_smart_server.error_verb
                    if error_verb == 'BadSearch':
                        # Pre-2.4 servers don't support this sort of search.
                        # XXX: perhaps falling back to VFS on BadSearch is a
                        # good idea in general?  It might provide a little bit
                        # of protection against client-side bugs.
                        medium._remember_remote_is_before((2, 4))
                        break
                raise
            else:
                response_tuple, response_handler = response
                found_verb = True
                break
        if not found_verb:
            return self._real_stream(repo, search)
        if response_tuple[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response_tuple)
        byte_stream = response_handler.read_streamed_body()
        src_format, stream = smart_repo._byte_stream_to_stream(byte_stream,
            self._record_counter)
        if src_format.network_name() != repo._format.network_name():
            raise AssertionError(
                "Mismatched RemoteRepository and stream src %r, %r" % (
                src_format.network_name(), repo._format.network_name()))
        return stream

    def missing_parents_chain(self, search, sources):
        """Chain multiple streams together to handle stacking.

        :param search: The overall search to satisfy with streams.
        :param sources: A list of Repository objects to query.
        """
        self.from_serialiser = self.from_repository._format._serializer
        self.seen_revs = set()
        self.referenced_revs = set()
        # If there are heads in the search, or the key count is > 0, we are not
        # done.
        while not search.is_empty() and len(sources) > 1:
            source = sources.pop(0)
            stream = self._get_stream(source, search)
            for kind, substream in stream:
                if kind != 'revisions':
                    yield kind, substream
                else:
                    yield kind, self.missing_parents_rev_handler(substream)
            search = search.refine(self.seen_revs, self.referenced_revs)
            self.seen_revs = set()
            self.referenced_revs = set()
        if not search.is_empty():
            for kind, stream in self._get_stream(sources[0], search):
                yield kind, stream

    def missing_parents_rev_handler(self, substream):
        for content in substream:
            revision_bytes = content.get_bytes_as('fulltext')
            revision = self.from_serialiser.read_revision_from_string(
                revision_bytes)
            self.seen_revs.add(content.key[-1])
            self.referenced_revs.update(revision.parent_ids)
            yield content


class RemoteBranchLockableFiles(LockableFiles):
    """A 'LockableFiles' implementation that talks to a smart server.

    This is not a public interface class.
    """

    def __init__(self, bzrdir, _client):
        self.bzrdir = bzrdir
        self._client = _client
        self._need_find_modes = True
        LockableFiles.__init__(
            self, bzrdir.get_branch_transport(None),
            'lock', lockdir.LockDir)

    def _find_modes(self):
        # RemoteBranches don't let the client set the mode of control files.
        self._dir_mode = None
        self._file_mode = None


class RemoteBranchFormat(branch.BranchFormat):

    def __init__(self, network_name=None):
        super(RemoteBranchFormat, self).__init__()
        self._matchingbzrdir = RemoteBzrDirFormat()
        self._matchingbzrdir.set_branch_format(self)
        self._custom_format = None
        self._network_name = network_name

    def __eq__(self, other):
        return (isinstance(other, RemoteBranchFormat) and
            self.__dict__ == other.__dict__)

    def _ensure_real(self):
        if self._custom_format is None:
            self._custom_format = branch.network_format_registry.get(
                self._network_name)

    def get_format_description(self):
        self._ensure_real()
        return 'Remote: ' + self._custom_format.get_format_description()

    def network_name(self):
        return self._network_name

    def open(self, a_bzrdir, name=None, ignore_fallbacks=False):
        return a_bzrdir.open_branch(name=name, 
            ignore_fallbacks=ignore_fallbacks)

    def _vfs_initialize(self, a_bzrdir, name):
        # Initialisation when using a local bzrdir object, or a non-vfs init
        # method is not available on the server.
        # self._custom_format is always set - the start of initialize ensures
        # that.
        if isinstance(a_bzrdir, RemoteBzrDir):
            a_bzrdir._ensure_real()
            result = self._custom_format.initialize(a_bzrdir._real_bzrdir,
                name)
        else:
            # We assume the bzrdir is parameterised; it may not be.
            result = self._custom_format.initialize(a_bzrdir, name)
        if (isinstance(a_bzrdir, RemoteBzrDir) and
            not isinstance(result, RemoteBranch)):
            result = RemoteBranch(a_bzrdir, a_bzrdir.find_repository(), result,
                                  name=name)
        return result

    def initialize(self, a_bzrdir, name=None, repository=None):
        # 1) get the network name to use.
        if self._custom_format:
            network_name = self._custom_format.network_name()
        else:
            # Select the current bzrlib default and ask for that.
            reference_bzrdir_format = _mod_bzrdir.format_registry.get('default')()
            reference_format = reference_bzrdir_format.get_branch_format()
            self._custom_format = reference_format
            network_name = reference_format.network_name()
        # Being asked to create on a non RemoteBzrDir:
        if not isinstance(a_bzrdir, RemoteBzrDir):
            return self._vfs_initialize(a_bzrdir, name=name)
        medium = a_bzrdir._client._medium
        if medium._is_remote_before((1, 13)):
            return self._vfs_initialize(a_bzrdir, name=name)
        # Creating on a remote bzr dir.
        # 2) try direct creation via RPC
        path = a_bzrdir._path_for_remote_call(a_bzrdir._client)
        if name is not None:
            # XXX JRV20100304: Support creating colocated branches
            raise errors.NoColocatedBranchSupport(self)
        verb = 'BzrDir.create_branch'
        try:
            response = a_bzrdir._call(verb, path, network_name)
        except errors.UnknownSmartMethod:
            # Fallback - use vfs methods
            medium._remember_remote_is_before((1, 13))
            return self._vfs_initialize(a_bzrdir, name=name)
        if response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        # Turn the response into a RemoteRepository object.
        format = RemoteBranchFormat(network_name=response[1])
        repo_format = response_tuple_to_repo_format(response[3:])
        repo_path = response[2]
        if repository is not None:
            remote_repo_url = urlutils.join(a_bzrdir.user_url, repo_path)
            url_diff = urlutils.relative_url(repository.user_url,
                    remote_repo_url)
            if url_diff != '.':
                raise AssertionError(
                    'repository.user_url %r does not match URL from server '
                    'response (%r + %r)'
                    % (repository.user_url, a_bzrdir.user_url, repo_path))
            remote_repo = repository
        else:
            if repo_path == '':
                repo_bzrdir = a_bzrdir
            else:
                repo_bzrdir = RemoteBzrDir(
                    a_bzrdir.root_transport.clone(repo_path), a_bzrdir._format,
                    a_bzrdir._client)
            remote_repo = RemoteRepository(repo_bzrdir, repo_format)
        remote_branch = RemoteBranch(a_bzrdir, remote_repo,
            format=format, setup_stacking=False, name=name)
        # XXX: We know this is a new branch, so it must have revno 0, revid
        # NULL_REVISION. Creating the branch locked would make this be unable
        # to be wrong; here its simply very unlikely to be wrong. RBC 20090225
        remote_branch._last_revision_info_cache = 0, NULL_REVISION
        return remote_branch

    def make_tags(self, branch):
        self._ensure_real()
        return self._custom_format.make_tags(branch)

    def supports_tags(self):
        # Remote branches might support tags, but we won't know until we
        # access the real remote branch.
        self._ensure_real()
        return self._custom_format.supports_tags()

    def supports_stacking(self):
        self._ensure_real()
        return self._custom_format.supports_stacking()

    def supports_set_append_revisions_only(self):
        self._ensure_real()
        return self._custom_format.supports_set_append_revisions_only()

    def _use_default_local_heads_to_fetch(self):
        # If the branch format is a metadir format *and* its heads_to_fetch
        # implementation is not overridden vs the base class, we can use the
        # base class logic rather than use the heads_to_fetch RPC.  This is
        # usually cheaper in terms of net round trips, as the last-revision and
        # tags info fetched is cached and would be fetched anyway.
        self._ensure_real()
        if isinstance(self._custom_format, branch.BranchFormatMetadir):
            branch_class = self._custom_format._branch_class()
            heads_to_fetch_impl = branch_class.heads_to_fetch.im_func
            if heads_to_fetch_impl is branch.Branch.heads_to_fetch.im_func:
                return True
        return False

class RemoteBranch(branch.Branch, _RpcHelper, lock._RelockDebugMixin):
    """Branch stored on a server accessed by HPSS RPC.

    At the moment most operations are mapped down to simple file operations.
    """

    def __init__(self, remote_bzrdir, remote_repository, real_branch=None,
        _client=None, format=None, setup_stacking=True, name=None):
        """Create a RemoteBranch instance.

        :param real_branch: An optional local implementation of the branch
            format, usually accessing the data via the VFS.
        :param _client: Private parameter for testing.
        :param format: A RemoteBranchFormat object, None to create one
            automatically. If supplied it should have a network_name already
            supplied.
        :param setup_stacking: If True make an RPC call to determine the
            stacked (or not) status of the branch. If False assume the branch
            is not stacked.
        :param name: Colocated branch name
        """
        # We intentionally don't call the parent class's __init__, because it
        # will try to assign to self.tags, which is a property in this subclass.
        # And the parent's __init__ doesn't do much anyway.
        self.bzrdir = remote_bzrdir
        if _client is not None:
            self._client = _client
        else:
            self._client = remote_bzrdir._client
        self.repository = remote_repository
        if real_branch is not None:
            self._real_branch = real_branch
            # Give the remote repository the matching real repo.
            real_repo = self._real_branch.repository
            if isinstance(real_repo, RemoteRepository):
                real_repo._ensure_real()
                real_repo = real_repo._real_repository
            self.repository._set_real_repository(real_repo)
            # Give the branch the remote repository to let fast-pathing happen.
            self._real_branch.repository = self.repository
        else:
            self._real_branch = None
        # Fill out expected attributes of branch for bzrlib API users.
        self._clear_cached_state()
        # TODO: deprecate self.base in favor of user_url
        self.base = self.bzrdir.user_url
        self._name = name
        self._control_files = None
        self._lock_mode = None
        self._lock_token = None
        self._repo_lock_token = None
        self._lock_count = 0
        self._leave_lock = False
        # Setup a format: note that we cannot call _ensure_real until all the
        # attributes above are set: This code cannot be moved higher up in this
        # function.
        if format is None:
            self._format = RemoteBranchFormat()
            if real_branch is not None:
                self._format._network_name = \
                    self._real_branch._format.network_name()
        else:
            self._format = format
        # when we do _ensure_real we may need to pass ignore_fallbacks to the
        # branch.open_branch method.
        self._real_ignore_fallbacks = not setup_stacking
        if not self._format._network_name:
            # Did not get from open_branchV2 - old server.
            self._ensure_real()
            self._format._network_name = \
                self._real_branch._format.network_name()
        self.tags = self._format.make_tags(self)
        # The base class init is not called, so we duplicate this:
        hooks = branch.Branch.hooks['open']
        for hook in hooks:
            hook(self)
        self._is_stacked = False
        if setup_stacking:
            self._setup_stacking()

    def _setup_stacking(self):
        # configure stacking into the remote repository, by reading it from
        # the vfs branch.
        try:
            fallback_url = self.get_stacked_on_url()
        except (errors.NotStacked, errors.UnstackableBranchFormat,
            errors.UnstackableRepositoryFormat), e:
            return
        self._is_stacked = True
        self._activate_fallback_location(fallback_url)

    def _get_config(self):
        return RemoteBranchConfig(self)

    def _get_real_transport(self):
        # if we try vfs access, return the real branch's vfs transport
        self._ensure_real()
        return self._real_branch._transport

    _transport = property(_get_real_transport)

    def __str__(self):
        return "%s(%s)" % (self.__class__.__name__, self.base)

    __repr__ = __str__

    def _ensure_real(self):
        """Ensure that there is a _real_branch set.

        Used before calls to self._real_branch.
        """
        if self._real_branch is None:
            if not vfs.vfs_enabled():
                raise AssertionError('smart server vfs must be enabled '
                    'to use vfs implementation')
            self.bzrdir._ensure_real()
            self._real_branch = self.bzrdir._real_bzrdir.open_branch(
                ignore_fallbacks=self._real_ignore_fallbacks, name=self._name)
            if self.repository._real_repository is None:
                # Give the remote repository the matching real repo.
                real_repo = self._real_branch.repository
                if isinstance(real_repo, RemoteRepository):
                    real_repo._ensure_real()
                    real_repo = real_repo._real_repository
                self.repository._set_real_repository(real_repo)
            # Give the real branch the remote repository to let fast-pathing
            # happen.
            self._real_branch.repository = self.repository
            if self._lock_mode == 'r':
                self._real_branch.lock_read()
            elif self._lock_mode == 'w':
                self._real_branch.lock_write(token=self._lock_token)

    def _translate_error(self, err, **context):
        self.repository._translate_error(err, branch=self, **context)

    def _clear_cached_state(self):
        super(RemoteBranch, self)._clear_cached_state()
        if self._real_branch is not None:
            self._real_branch._clear_cached_state()

    def _clear_cached_state_of_remote_branch_only(self):
        """Like _clear_cached_state, but doesn't clear the cache of
        self._real_branch.

        This is useful when falling back to calling a method of
        self._real_branch that changes state.  In that case the underlying
        branch changes, so we need to invalidate this RemoteBranch's cache of
        it.  However, there's no need to invalidate the _real_branch's cache
        too, in fact doing so might harm performance.
        """
        super(RemoteBranch, self)._clear_cached_state()

    @property
    def control_files(self):
        # Defer actually creating RemoteBranchLockableFiles until its needed,
        # because it triggers an _ensure_real that we otherwise might not need.
        if self._control_files is None:
            self._control_files = RemoteBranchLockableFiles(
                self.bzrdir, self._client)
        return self._control_files

    def _get_checkout_format(self):
        self._ensure_real()
        return self._real_branch._get_checkout_format()

    def get_physical_lock_status(self):
        """See Branch.get_physical_lock_status()."""
        # should be an API call to the server, as branches must be lockable.
        self._ensure_real()
        return self._real_branch.get_physical_lock_status()

    def get_stacked_on_url(self):
        """Get the URL this branch is stacked against.

        :raises NotStacked: If the branch is not stacked.
        :raises UnstackableBranchFormat: If the branch does not support
            stacking.
        :raises UnstackableRepositoryFormat: If the repository does not support
            stacking.
        """
        try:
            # there may not be a repository yet, so we can't use
            # self._translate_error, so we can't use self._call either.
            response = self._client.call('Branch.get_stacked_on_url',
                self._remote_path())
        except errors.ErrorFromSmartServer, err:
            # there may not be a repository yet, so we can't call through
            # its _translate_error
            _translate_error(err, branch=self)
        except errors.UnknownSmartMethod, err:
            self._ensure_real()
            return self._real_branch.get_stacked_on_url()
        if response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        return response[1]

    def set_stacked_on_url(self, url):
        branch.Branch.set_stacked_on_url(self, url)
        if not url:
            self._is_stacked = False
        else:
            self._is_stacked = True

    def _vfs_get_tags_bytes(self):
        self._ensure_real()
        return self._real_branch._get_tags_bytes()

    @needs_read_lock
    def _get_tags_bytes(self):
        if self._tags_bytes is None:
            self._tags_bytes = self._get_tags_bytes_via_hpss()
        return self._tags_bytes

    def _get_tags_bytes_via_hpss(self):
        medium = self._client._medium
        if medium._is_remote_before((1, 13)):
            return self._vfs_get_tags_bytes()
        try:
            response = self._call('Branch.get_tags_bytes', self._remote_path())
        except errors.UnknownSmartMethod:
            medium._remember_remote_is_before((1, 13))
            return self._vfs_get_tags_bytes()
        return response[0]

    def _vfs_set_tags_bytes(self, bytes):
        self._ensure_real()
        return self._real_branch._set_tags_bytes(bytes)

    def _set_tags_bytes(self, bytes):
        if self.is_locked():
            self._tags_bytes = bytes
        medium = self._client._medium
        if medium._is_remote_before((1, 18)):
            self._vfs_set_tags_bytes(bytes)
            return
        try:
            args = (
                self._remote_path(), self._lock_token, self._repo_lock_token)
            response = self._call_with_body_bytes(
                'Branch.set_tags_bytes', args, bytes)
        except errors.UnknownSmartMethod:
            medium._remember_remote_is_before((1, 18))
            self._vfs_set_tags_bytes(bytes)

    def lock_read(self):
        """Lock the branch for read operations.

        :return: A bzrlib.lock.LogicalLockResult.
        """
        self.repository.lock_read()
        if not self._lock_mode:
            self._note_lock('r')
            self._lock_mode = 'r'
            self._lock_count = 1
            if self._real_branch is not None:
                self._real_branch.lock_read()
        else:
            self._lock_count += 1
        return lock.LogicalLockResult(self.unlock)

    def _remote_lock_write(self, token):
        if token is None:
            branch_token = repo_token = ''
        else:
            branch_token = token
            repo_token = self.repository.lock_write().repository_token
            self.repository.unlock()
        err_context = {'token': token}
        try:
            response = self._call(
                'Branch.lock_write', self._remote_path(), branch_token,
                repo_token or '', **err_context)
        except errors.LockContention, e:
            # The LockContention from the server doesn't have any
            # information about the lock_url. We re-raise LockContention
            # with valid lock_url.
            raise errors.LockContention('(remote lock)',
                self.repository.base.split('.bzr/')[0])
        if response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        ok, branch_token, repo_token = response
        return branch_token, repo_token

    def lock_write(self, token=None):
        if not self._lock_mode:
            self._note_lock('w')
            # Lock the branch and repo in one remote call.
            remote_tokens = self._remote_lock_write(token)
            self._lock_token, self._repo_lock_token = remote_tokens
            if not self._lock_token:
                raise SmartProtocolError('Remote server did not return a token!')
            # Tell the self.repository object that it is locked.
            self.repository.lock_write(
                self._repo_lock_token, _skip_rpc=True)

            if self._real_branch is not None:
                self._real_branch.lock_write(token=self._lock_token)
            if token is not None:
                self._leave_lock = True
            else:
                self._leave_lock = False
            self._lock_mode = 'w'
            self._lock_count = 1
        elif self._lock_mode == 'r':
            raise errors.ReadOnlyError(self)
        else:
            if token is not None:
                # A token was given to lock_write, and we're relocking, so
                # check that the given token actually matches the one we
                # already have.
                if token != self._lock_token:
                    raise errors.TokenMismatch(token, self._lock_token)
            self._lock_count += 1
            # Re-lock the repository too.
            self.repository.lock_write(self._repo_lock_token)
        return BranchWriteLockResult(self.unlock, self._lock_token or None)

    def _unlock(self, branch_token, repo_token):
        err_context = {'token': str((branch_token, repo_token))}
        response = self._call(
            'Branch.unlock', self._remote_path(), branch_token,
            repo_token or '', **err_context)
        if response == ('ok',):
            return
        raise errors.UnexpectedSmartServerResponse(response)

    @only_raises(errors.LockNotHeld, errors.LockBroken)
    def unlock(self):
        try:
            self._lock_count -= 1
            if not self._lock_count:
                self._clear_cached_state()
                mode = self._lock_mode
                self._lock_mode = None
                if self._real_branch is not None:
                    if (not self._leave_lock and mode == 'w' and
                        self._repo_lock_token):
                        # If this RemoteBranch will remove the physical lock
                        # for the repository, make sure the _real_branch
                        # doesn't do it first.  (Because the _real_branch's
                        # repository is set to be the RemoteRepository.)
                        self._real_branch.repository.leave_lock_in_place()
                    self._real_branch.unlock()
                if mode != 'w':
                    # Only write-locked branched need to make a remote method
                    # call to perform the unlock.
                    return
                if not self._lock_token:
                    raise AssertionError('Locked, but no token!')
                branch_token = self._lock_token
                repo_token = self._repo_lock_token
                self._lock_token = None
                self._repo_lock_token = None
                if not self._leave_lock:
                    self._unlock(branch_token, repo_token)
        finally:
            self.repository.unlock()

    def break_lock(self):
        self._ensure_real()
        return self._real_branch.break_lock()

    def leave_lock_in_place(self):
        if not self._lock_token:
            raise NotImplementedError(self.leave_lock_in_place)
        self._leave_lock = True

    def dont_leave_lock_in_place(self):
        if not self._lock_token:
            raise NotImplementedError(self.dont_leave_lock_in_place)
        self._leave_lock = False

    @needs_read_lock
    def get_rev_id(self, revno, history=None):
        if revno == 0:
            return _mod_revision.NULL_REVISION
        last_revision_info = self.last_revision_info()
        ok, result = self.repository.get_rev_id_for_revno(
            revno, last_revision_info)
        if ok:
            return result
        missing_parent = result[1]
        # Either the revision named by the server is missing, or its parent
        # is.  Call get_parent_map to determine which, so that we report a
        # useful error.
        parent_map = self.repository.get_parent_map([missing_parent])
        if missing_parent in parent_map:
            missing_parent = parent_map[missing_parent]
        raise errors.RevisionNotPresent(missing_parent, self.repository)

    def _last_revision_info(self):
        response = self._call('Branch.last_revision_info', self._remote_path())
        if response[0] != 'ok':
            raise SmartProtocolError('unexpected response code %s' % (response,))
        revno = int(response[1])
        last_revision = response[2]
        return (revno, last_revision)

    def _gen_revision_history(self):
        """See Branch._gen_revision_history()."""
        if self._is_stacked:
            self._ensure_real()
            return self._real_branch._gen_revision_history()
        response_tuple, response_handler = self._call_expecting_body(
            'Branch.revision_history', self._remote_path())
        if response_tuple[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response_tuple)
        result = response_handler.read_body_bytes().split('\x00')
        if result == ['']:
            return []
        return result

    def _remote_path(self):
        return self.bzrdir._path_for_remote_call(self._client)

    def _set_last_revision_descendant(self, revision_id, other_branch,
            allow_diverged=False, allow_overwrite_descendant=False):
        # This performs additional work to meet the hook contract; while its
        # undesirable, we have to synthesise the revno to call the hook, and
        # not calling the hook is worse as it means changes can't be prevented.
        # Having calculated this though, we can't just call into
        # set_last_revision_info as a simple call, because there is a set_rh
        # hook that some folk may still be using.
        old_revno, old_revid = self.last_revision_info()
        history = self._lefthand_history(revision_id)
        self._run_pre_change_branch_tip_hooks(len(history), revision_id)
        err_context = {'other_branch': other_branch}
        response = self._call('Branch.set_last_revision_ex',
            self._remote_path(), self._lock_token, self._repo_lock_token,
            revision_id, int(allow_diverged), int(allow_overwrite_descendant),
            **err_context)
        self._clear_cached_state()
        if len(response) != 3 and response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        new_revno, new_revision_id = response[1:]
        self._last_revision_info_cache = new_revno, new_revision_id
        self._run_post_change_branch_tip_hooks(old_revno, old_revid)
        if self._real_branch is not None:
            cache = new_revno, new_revision_id
            self._real_branch._last_revision_info_cache = cache

    def _set_last_revision(self, revision_id):
        old_revno, old_revid = self.last_revision_info()
        # This performs additional work to meet the hook contract; while its
        # undesirable, we have to synthesise the revno to call the hook, and
        # not calling the hook is worse as it means changes can't be prevented.
        # Having calculated this though, we can't just call into
        # set_last_revision_info as a simple call, because there is a set_rh
        # hook that some folk may still be using.
        history = self._lefthand_history(revision_id)
        self._run_pre_change_branch_tip_hooks(len(history), revision_id)
        self._clear_cached_state()
        response = self._call('Branch.set_last_revision',
            self._remote_path(), self._lock_token, self._repo_lock_token,
            revision_id)
        if response != ('ok',):
            raise errors.UnexpectedSmartServerResponse(response)
        self._run_post_change_branch_tip_hooks(old_revno, old_revid)

    @needs_write_lock
    def set_revision_history(self, rev_history):
        # Send just the tip revision of the history; the server will generate
        # the full history from that.  If the revision doesn't exist in this
        # branch, NoSuchRevision will be raised.
        if rev_history == []:
            rev_id = 'null:'
        else:
            rev_id = rev_history[-1]
        self._set_last_revision(rev_id)
        for hook in branch.Branch.hooks['set_rh']:
            hook(self, rev_history)
        self._cache_revision_history(rev_history)

    def _get_parent_location(self):
        medium = self._client._medium
        if medium._is_remote_before((1, 13)):
            return self._vfs_get_parent_location()
        try:
            response = self._call('Branch.get_parent', self._remote_path())
        except errors.UnknownSmartMethod:
            medium._remember_remote_is_before((1, 13))
            return self._vfs_get_parent_location()
        if len(response) != 1:
            raise errors.UnexpectedSmartServerResponse(response)
        parent_location = response[0]
        if parent_location == '':
            return None
        return parent_location

    def _vfs_get_parent_location(self):
        self._ensure_real()
        return self._real_branch._get_parent_location()

    def _set_parent_location(self, url):
        medium = self._client._medium
        if medium._is_remote_before((1, 15)):
            return self._vfs_set_parent_location(url)
        try:
            call_url = url or ''
            if type(call_url) is not str:
                raise AssertionError('url must be a str or None (%s)' % url)
            response = self._call('Branch.set_parent_location',
                self._remote_path(), self._lock_token, self._repo_lock_token,
                call_url)
        except errors.UnknownSmartMethod:
            medium._remember_remote_is_before((1, 15))
            return self._vfs_set_parent_location(url)
        if response != ():
            raise errors.UnexpectedSmartServerResponse(response)

    def _vfs_set_parent_location(self, url):
        self._ensure_real()
        return self._real_branch._set_parent_location(url)

    @needs_write_lock
    def pull(self, source, overwrite=False, stop_revision=None,
             **kwargs):
        self._clear_cached_state_of_remote_branch_only()
        self._ensure_real()
        return self._real_branch.pull(
            source, overwrite=overwrite, stop_revision=stop_revision,
            _override_hook_target=self, **kwargs)

    @needs_read_lock
    def push(self, target, overwrite=False, stop_revision=None):
        self._ensure_real()
        return self._real_branch.push(
            target, overwrite=overwrite, stop_revision=stop_revision,
            _override_hook_source_branch=self)

    def is_locked(self):
        return self._lock_count >= 1

    @needs_read_lock
    def revision_id_to_revno(self, revision_id):
        self._ensure_real()
        return self._real_branch.revision_id_to_revno(revision_id)

    @needs_write_lock
    def set_last_revision_info(self, revno, revision_id):
        # XXX: These should be returned by the set_last_revision_info verb
        old_revno, old_revid = self.last_revision_info()
        self._run_pre_change_branch_tip_hooks(revno, revision_id)
        revision_id = _mod_revision.ensure_null(revision_id)
        try:
            response = self._call('Branch.set_last_revision_info',
                self._remote_path(), self._lock_token, self._repo_lock_token,
                str(revno), revision_id)
        except errors.UnknownSmartMethod:
            self._ensure_real()
            self._clear_cached_state_of_remote_branch_only()
            self._real_branch.set_last_revision_info(revno, revision_id)
            self._last_revision_info_cache = revno, revision_id
            return
        if response == ('ok',):
            self._clear_cached_state()
            self._last_revision_info_cache = revno, revision_id
            self._run_post_change_branch_tip_hooks(old_revno, old_revid)
            # Update the _real_branch's cache too.
            if self._real_branch is not None:
                cache = self._last_revision_info_cache
                self._real_branch._last_revision_info_cache = cache
        else:
            raise errors.UnexpectedSmartServerResponse(response)

    @needs_write_lock
    def generate_revision_history(self, revision_id, last_rev=None,
                                  other_branch=None):
        medium = self._client._medium
        if not medium._is_remote_before((1, 6)):
            # Use a smart method for 1.6 and above servers
            try:
                self._set_last_revision_descendant(revision_id, other_branch,
                    allow_diverged=True, allow_overwrite_descendant=True)
                return
            except errors.UnknownSmartMethod:
                medium._remember_remote_is_before((1, 6))
        self._clear_cached_state_of_remote_branch_only()
        self.set_revision_history(self._lefthand_history(revision_id,
            last_rev=last_rev,other_branch=other_branch))

    def set_push_location(self, location):
        self._ensure_real()
        return self._real_branch.set_push_location(location)

    def heads_to_fetch(self):
        if self._format._use_default_local_heads_to_fetch():
            # We recognise this format, and its heads-to-fetch implementation
            # is the default one (tip + tags).  In this case it's cheaper to
            # just use the default implementation rather than a special RPC as
            # the tip and tags data is cached.
            return branch.Branch.heads_to_fetch(self)
        medium = self._client._medium
        if medium._is_remote_before((2, 4)):
            return self._vfs_heads_to_fetch()
        try:
            return self._rpc_heads_to_fetch()
        except errors.UnknownSmartMethod:
            medium._remember_remote_is_before((2, 4))
            return self._vfs_heads_to_fetch()

    def _rpc_heads_to_fetch(self):
        response = self._call('Branch.heads_to_fetch', self._remote_path())
        if len(response) != 2:
            raise errors.UnexpectedSmartServerResponse(response)
        must_fetch, if_present_fetch = response
        return set(must_fetch), set(if_present_fetch)

    def _vfs_heads_to_fetch(self):
        self._ensure_real()
        return self._real_branch.heads_to_fetch()


class RemoteConfig(object):
    """A Config that reads and writes from smart verbs.

    It is a low-level object that considers config data to be name/value pairs
    that may be associated with a section. Assigning meaning to the these
    values is done at higher levels like bzrlib.config.TreeConfig.
    """

    def get_option(self, name, section=None, default=None):
        """Return the value associated with a named option.

        :param name: The name of the value
        :param section: The section the option is in (if any)
        :param default: The value to return if the value is not set
        :return: The value or default value
        """
        try:
            configobj = self._get_configobj()
            if section is None:
                section_obj = configobj
            else:
                try:
                    section_obj = configobj[section]
                except KeyError:
                    return default
            return section_obj.get(name, default)
        except errors.UnknownSmartMethod:
            return self._vfs_get_option(name, section, default)

    def _response_to_configobj(self, response):
        if len(response[0]) and response[0][0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        lines = response[1].read_body_bytes().splitlines()
        return config.ConfigObj(lines, encoding='utf-8')


class RemoteBranchConfig(RemoteConfig):
    """A RemoteConfig for Branches."""

    def __init__(self, branch):
        self._branch = branch

    def _get_configobj(self):
        path = self._branch._remote_path()
        response = self._branch._client.call_expecting_body(
            'Branch.get_config_file', path)
        return self._response_to_configobj(response)

    def set_option(self, value, name, section=None):
        """Set the value associated with a named option.

        :param value: The value to set
        :param name: The name of the value to set
        :param section: The section the option is in (if any)
        """
        medium = self._branch._client._medium
        if medium._is_remote_before((1, 14)):
            return self._vfs_set_option(value, name, section)
        if isinstance(value, dict):
            if medium._is_remote_before((2, 2)):
                return self._vfs_set_option(value, name, section)
            return self._set_config_option_dict(value, name, section)
        else:
            return self._set_config_option(value, name, section)

    def _set_config_option(self, value, name, section):
        try:
            path = self._branch._remote_path()
            response = self._branch._client.call('Branch.set_config_option',
                path, self._branch._lock_token, self._branch._repo_lock_token,
                value.encode('utf8'), name, section or '')
        except errors.UnknownSmartMethod:
            medium = self._branch._client._medium
            medium._remember_remote_is_before((1, 14))
            return self._vfs_set_option(value, name, section)
        if response != ():
            raise errors.UnexpectedSmartServerResponse(response)

    def _serialize_option_dict(self, option_dict):
        utf8_dict = {}
        for key, value in option_dict.items():
            if isinstance(key, unicode):
                key = key.encode('utf8')
            if isinstance(value, unicode):
                value = value.encode('utf8')
            utf8_dict[key] = value
        return bencode.bencode(utf8_dict)

    def _set_config_option_dict(self, value, name, section):
        try:
            path = self._branch._remote_path()
            serialised_dict = self._serialize_option_dict(value)
            response = self._branch._client.call(
                'Branch.set_config_option_dict',
                path, self._branch._lock_token, self._branch._repo_lock_token,
                serialised_dict, name, section or '')
        except errors.UnknownSmartMethod:
            medium = self._branch._client._medium
            medium._remember_remote_is_before((2, 2))
            return self._vfs_set_option(value, name, section)
        if response != ():
            raise errors.UnexpectedSmartServerResponse(response)

    def _real_object(self):
        self._branch._ensure_real()
        return self._branch._real_branch

    def _vfs_set_option(self, value, name, section=None):
        return self._real_object()._get_config().set_option(
            value, name, section)


class RemoteBzrDirConfig(RemoteConfig):
    """A RemoteConfig for BzrDirs."""

    def __init__(self, bzrdir):
        self._bzrdir = bzrdir

    def _get_configobj(self):
        medium = self._bzrdir._client._medium
        verb = 'BzrDir.get_config_file'
        if medium._is_remote_before((1, 15)):
            raise errors.UnknownSmartMethod(verb)
        path = self._bzrdir._path_for_remote_call(self._bzrdir._client)
        response = self._bzrdir._call_expecting_body(
            verb, path)
        return self._response_to_configobj(response)

    def _vfs_get_option(self, name, section, default):
        return self._real_object()._get_config().get_option(
            name, section, default)

    def set_option(self, value, name, section=None):
        """Set the value associated with a named option.

        :param value: The value to set
        :param name: The name of the value to set
        :param section: The section the option is in (if any)
        """
        return self._real_object()._get_config().set_option(
            value, name, section)

    def _real_object(self):
        self._bzrdir._ensure_real()
        return self._bzrdir._real_bzrdir



def _extract_tar(tar, to_dir):
    """Extract all the contents of a tarfile object.

    A replacement for extractall, which is not present in python2.4
    """
    for tarinfo in tar:
        tar.extract(tarinfo, to_dir)


def _translate_error(err, **context):
    """Translate an ErrorFromSmartServer into a more useful error.

    Possible context keys:
      - branch
      - repository
      - bzrdir
      - token
      - other_branch
      - path

    If the error from the server doesn't match a known pattern, then
    UnknownErrorFromSmartServer is raised.
    """
    def find(name):
        try:
            return context[name]
        except KeyError, key_err:
            mutter('Missing key %r in context %r', key_err.args[0], context)
            raise err
    def get_path():
        """Get the path from the context if present, otherwise use first error
        arg.
        """
        try:
            return context['path']
        except KeyError, key_err:
            try:
                return err.error_args[0]
            except IndexError, idx_err:
                mutter(
                    'Missing key %r in context %r', key_err.args[0], context)
                raise err

    if err.error_verb == 'NoSuchRevision':
        raise NoSuchRevision(find('branch'), err.error_args[0])
    elif err.error_verb == 'nosuchrevision':
        raise NoSuchRevision(find('repository'), err.error_args[0])
    elif err.error_verb == 'nobranch':
        if len(err.error_args) >= 1:
            extra = err.error_args[0]
        else:
            extra = None
        raise errors.NotBranchError(path=find('bzrdir').root_transport.base,
            detail=extra)
    elif err.error_verb == 'norepository':
        raise errors.NoRepositoryPresent(find('bzrdir'))
    elif err.error_verb == 'UnlockableTransport':
        raise errors.UnlockableTransport(find('bzrdir').root_transport)
    elif err.error_verb == 'TokenMismatch':
        raise errors.TokenMismatch(find('token'), '(remote token)')
    elif err.error_verb == 'Diverged':
        raise errors.DivergedBranches(find('branch'), find('other_branch'))
    elif err.error_verb == 'NotStacked':
        raise errors.NotStacked(branch=find('branch'))
    elif err.error_verb == 'PermissionDenied':
        path = get_path()
        if len(err.error_args) >= 2:
            extra = err.error_args[1]
        else:
            extra = None
        raise errors.PermissionDenied(path, extra=extra)
    elif err.error_verb == 'ReadError':
        path = get_path()
        raise errors.ReadError(path)
    elif err.error_verb == 'NoSuchFile':
        path = get_path()
        raise errors.NoSuchFile(path)
    _translate_error_without_context(err)


def _translate_error_without_context(err):
    """Translate any ErrorFromSmartServer values that don't require context"""
    if err.error_verb == 'IncompatibleRepositories':
        raise errors.IncompatibleRepositories(err.error_args[0],
            err.error_args[1], err.error_args[2])
    elif err.error_verb == 'LockContention':
        raise errors.LockContention('(remote lock)')
    elif err.error_verb == 'LockFailed':
        raise errors.LockFailed(err.error_args[0], err.error_args[1])
    elif err.error_verb == 'TipChangeRejected':
        raise errors.TipChangeRejected(err.error_args[0].decode('utf8'))
    elif err.error_verb == 'UnstackableBranchFormat':
        raise errors.UnstackableBranchFormat(*err.error_args)
    elif err.error_verb == 'UnstackableRepositoryFormat':
        raise errors.UnstackableRepositoryFormat(*err.error_args)
    elif err.error_verb == 'FileExists':
        raise errors.FileExists(err.error_args[0])
    elif err.error_verb == 'DirectoryNotEmpty':
        raise errors.DirectoryNotEmpty(err.error_args[0])
    elif err.error_verb == 'ShortReadvError':
        args = err.error_args
        raise errors.ShortReadvError(
            args[0], int(args[1]), int(args[2]), int(args[3]))
    elif err.error_verb in ('UnicodeEncodeError', 'UnicodeDecodeError'):
        encoding = str(err.error_args[0]) # encoding must always be a string
        val = err.error_args[1]
        start = int(err.error_args[2])
        end = int(err.error_args[3])
        reason = str(err.error_args[4]) # reason must always be a string
        if val.startswith('u:'):
            val = val[2:].decode('utf-8')
        elif val.startswith('s:'):
            val = val[2:].decode('base64')
        if err.error_verb == 'UnicodeDecodeError':
            raise UnicodeDecodeError(encoding, val, start, end, reason)
        elif err.error_verb == 'UnicodeEncodeError':
            raise UnicodeEncodeError(encoding, val, start, end, reason)
    elif err.error_verb == 'ReadOnlyError':
        raise errors.TransportNotPossible('readonly transport')
    elif err.error_verb == 'MemoryError':
        raise errors.BzrError("remote server out of memory\n"
            "Retry non-remotely, or contact the server admin for details.")
    raise errors.UnknownErrorFromSmartServer(err)