135
class _SFTPReadvHelper(object):
136
"""A class to help with managing the state of a readv request."""
138
# See _get_requests for an explanation.
139
_max_request_size = 32768
141
def __init__(self, original_offsets, relpath, _report_activity):
142
"""Create a new readv helper.
144
:param original_offsets: The original requests given by the caller of
146
:param relpath: The name of the file (if known)
147
:param _report_activity: A Transport._report_activity bound method,
148
to be called as data arrives.
150
self.original_offsets = list(original_offsets)
151
self.relpath = relpath
152
self._report_activity = _report_activity
154
def _get_requests(self):
155
"""Break up the offsets into individual requests over sftp.
157
The SFTP spec only requires implementers to support 32kB requests. We
158
could try something larger (openssh supports 64kB), but then we have to
159
handle requests that fail.
160
So instead, we just break up our maximum chunks into 32kB chunks, and
161
asyncronously requests them.
162
Newer versions of paramiko would do the chunking for us, but we want to
163
start processing results right away, so we do it ourselves.
165
# TODO: Because we issue async requests, we don't 'fudge' any extra
166
# data. I'm not 100% sure that is the best choice.
168
# The first thing we do, is to collapse the individual requests as much
169
# as possible, so we don't issues requests <32kB
170
sorted_offsets = sorted(self.original_offsets)
171
coalesced = list(ConnectedTransport._coalesce_offsets(sorted_offsets,
172
limit=0, fudge_factor=0))
174
for c_offset in coalesced:
175
start = c_offset.start
176
size = c_offset.length
178
# Break this up into 32kB requests
180
next_size = min(size, self._max_request_size)
181
requests.append((start, next_size))
184
if 'sftp' in debug.debug_flags:
185
mutter('SFTP.readv(%s) %s offsets => %s coalesced => %s requests',
186
self.relpath, len(sorted_offsets), len(coalesced),
190
def request_and_yield_offsets(self, fp):
191
"""Request the data from the remote machine, yielding the results.
193
:param fp: A Paramiko SFTPFile object that supports readv.
194
:return: Yield the data requested by the original readv caller, one by
197
requests = self._get_requests()
198
offset_iter = iter(self.original_offsets)
199
cur_offset, cur_size = offset_iter.next()
200
# paramiko .readv() yields strings that are in the order of the requests
201
# So we track the current request to know where the next data is
202
# being returned from.
208
# This is used to buffer chunks which we couldn't process yet
209
# It is (start, end, data) tuples.
211
# Create an 'unlimited' data stream, so we stop based on requests,
212
# rather than just because the data stream ended. This lets us detect
214
data_stream = itertools.chain(fp.readv(requests),
215
itertools.repeat(None))
216
for (start, length), data in itertools.izip(requests, data_stream):
218
if cur_coalesced is not None:
219
raise errors.ShortReadvError(self.relpath,
220
start, length, len(data))
221
if len(data) != length:
222
raise errors.ShortReadvError(self.relpath,
223
start, length, len(data))
224
self._report_activity(length, 'read')
226
# This is the first request, just buffer it
227
buffered_data = [data]
228
buffered_len = length
230
elif start == last_end:
231
# The data we are reading fits neatly on the previous
232
# buffer, so this is all part of a larger coalesced range.
233
buffered_data.append(data)
234
buffered_len += length
236
# We have an 'interrupt' in the data stream. So we know we are
237
# at a request boundary.
239
# We haven't consumed the buffer so far, so put it into
240
# data_chunks, and continue.
241
buffered = ''.join(buffered_data)
242
data_chunks.append((input_start, buffered))
244
buffered_data = [data]
245
buffered_len = length
246
last_end = start + length
247
if input_start == cur_offset and cur_size <= buffered_len:
248
# Simplify the next steps a bit by transforming buffered_data
249
# into a single string. We also have the nice property that
250
# when there is only one string ''.join([x]) == x, so there is
252
buffered = ''.join(buffered_data)
253
# Clean out buffered data so that we keep memory
257
# TODO: We *could* also consider the case where cur_offset is in
258
# in the buffered range, even though it doesn't *start*
259
# the buffered range. But for packs we pretty much always
260
# read in order, so you won't get any extra data in the
262
while (input_start == cur_offset
263
and (buffered_offset + cur_size) <= buffered_len):
264
# We've buffered enough data to process this request, spit it
266
cur_data = buffered[buffered_offset:buffered_offset + cur_size]
267
# move the direct pointer into our buffered data
268
buffered_offset += cur_size
269
# Move the start-of-buffer pointer
270
input_start += cur_size
271
# Yield the requested data
272
yield cur_offset, cur_data
273
cur_offset, cur_size = offset_iter.next()
274
# at this point, we've consumed as much of buffered as we can,
275
# so break off the portion that we consumed
276
if buffered_offset == len(buffered_data):
277
# No tail to leave behind
281
buffered = buffered[buffered_offset:]
282
buffered_data = [buffered]
283
buffered_len = len(buffered)
285
buffered = ''.join(buffered_data)
287
data_chunks.append((input_start, buffered))
289
if 'sftp' in debug.debug_flags:
290
mutter('SFTP readv left with %d out-of-order bytes',
291
sum(map(lambda x: len(x[1]), data_chunks)))
292
# We've processed all the readv data, at this point, anything we
293
# couldn't process is in data_chunks. This doesn't happen often, so
294
# this code path isn't optimized
295
# We use an interesting process for data_chunks
296
# Specifically if we have "bisect_left([(start, len, entries)],
298
# If start == qstart, then we get the specific node. Otherwise we
299
# get the previous node
301
idx = bisect.bisect_left(data_chunks, (cur_offset,))
302
if idx < len(data_chunks) and data_chunks[idx][0] == cur_offset:
303
# The data starts here
304
data = data_chunks[idx][1][:cur_size]
306
# The data is in a portion of a previous page
308
sub_offset = cur_offset - data_chunks[idx][0]
309
data = data_chunks[idx][1]
310
data = data[sub_offset:sub_offset + cur_size]
312
# We are missing the page where the data should be found,
315
if len(data) != cur_size:
316
raise AssertionError('We must have miscalulated.'
317
' We expected %d bytes, but only found %d'
318
% (cur_size, len(data)))
319
yield cur_offset, data
320
cur_offset, cur_size = offset_iter.next()
323
149
class SFTPTransport(ConnectedTransport):
324
150
"""Transport implementation for SFTP access."""
471
def _sftp_readv(self, fp, offsets, relpath):
277
def _sftp_readv(self, fp, offsets, relpath='<unknown>'):
472
278
"""Use the readv() member of fp to do async readv.
474
Then read them using paramiko.readv(). paramiko.readv()
280
And then read them using paramiko.readv(). paramiko.readv()
475
281
does not support ranges > 64K, so it caps the request size, and
476
just reads until it gets all the stuff it wants.
282
just reads until it gets all the stuff it wants
478
helper = _SFTPReadvHelper(offsets, relpath, self._report_activity)
479
return helper.request_and_yield_offsets(fp)
284
offsets = list(offsets)
285
sorted_offsets = sorted(offsets)
287
# The algorithm works as follows:
288
# 1) Coalesce nearby reads into a single chunk
289
# This generates a list of combined regions, the total size
290
# and the size of the sub regions. This coalescing step is limited
291
# in the number of nearby chunks to combine, and is allowed to
292
# skip small breaks in the requests. Limiting it makes sure that
293
# we can start yielding some data earlier, and skipping means we
294
# make fewer requests. (Beneficial even when using async)
295
# 2) Break up this combined regions into chunks that are smaller
296
# than 64KiB. Technically the limit is 65536, but we are a
297
# little bit conservative. This is because sftp has a maximum
298
# return chunk size of 64KiB (max size of an unsigned short)
299
# 3) Issue a readv() to paramiko to create an async request for
301
# 4) Read in the data as it comes back, until we've read one
302
# continuous section as determined in step 1
303
# 5) Break up the full sections into hunks for the original requested
304
# offsets. And put them in a cache
305
# 6) Check if the next request is in the cache, and if it is, remove
306
# it from the cache, and yield its data. Continue until no more
307
# entries are in the cache.
308
# 7) loop back to step 4 until all data has been read
310
# TODO: jam 20060725 This could be optimized one step further, by
311
# attempting to yield whatever data we have read, even before
312
# the first coallesced section has been fully processed.
314
# When coalescing for use with readv(), we don't really need to
315
# use any fudge factor, because the requests are made asynchronously
316
coalesced = list(self._coalesce_offsets(sorted_offsets,
317
limit=self._max_readv_combine,
321
for c_offset in coalesced:
322
start = c_offset.start
323
size = c_offset.length
325
# We need to break this up into multiple requests
327
next_size = min(size, self._max_request_size)
328
requests.append((start, next_size))
332
mutter('SFTP.readv() %s offsets => %s coalesced => %s requests',
333
len(offsets), len(coalesced), len(requests))
335
# Queue the current read until we have read the full coalesced section
338
cur_coalesced_stack = iter(coalesced)
339
cur_coalesced = cur_coalesced_stack.next()
341
# Cache the results, but only until they have been fulfilled
343
# turn the list of offsets into a stack
344
offset_stack = iter(offsets)
345
cur_offset_and_size = offset_stack.next()
347
for data in fp.readv(requests):
349
cur_data_len += len(data)
351
if cur_data_len < cur_coalesced.length:
353
assert cur_data_len == cur_coalesced.length, \
354
"Somehow we read too much: %s != %s" % (cur_data_len,
355
cur_coalesced.length)
356
all_data = ''.join(cur_data)
360
for suboffset, subsize in cur_coalesced.ranges:
361
key = (cur_coalesced.start+suboffset, subsize)
362
data_map[key] = all_data[suboffset:suboffset+subsize]
364
# Now that we've read some data, see if we can yield anything back
365
while cur_offset_and_size in data_map:
366
this_data = data_map.pop(cur_offset_and_size)
367
yield cur_offset_and_size[0], this_data
368
cur_offset_and_size = offset_stack.next()
370
# We read a coalesced entry, so mark it as done
372
# Now that we've read all of the data for this coalesced section
374
cur_coalesced = cur_coalesced_stack.next()
376
if cur_coalesced is not None:
377
raise errors.ShortReadvError(relpath, cur_coalesced.start,
378
cur_coalesced.length, len(data))
481
380
def put_file(self, relpath, f, mode=None):
759
# ------------- server test implementation --------------
762
from bzrlib.tests.stub_sftp import StubServer, StubSFTPServer
764
STUB_SERVER_KEY = """
765
-----BEGIN RSA PRIVATE KEY-----
766
MIICWgIBAAKBgQDTj1bqB4WmayWNPB+8jVSYpZYk80Ujvj680pOTh2bORBjbIAyz
767
oWGW+GUjzKxTiiPvVmxFgx5wdsFvF03v34lEVVhMpouqPAYQ15N37K/ir5XY+9m/
768
d8ufMCkjeXsQkKqFbAlQcnWMCRnOoPHS3I4vi6hmnDDeeYTSRvfLbW0fhwIBIwKB
769
gBIiOqZYaoqbeD9OS9z2K9KR2atlTxGxOJPXiP4ESqP3NVScWNwyZ3NXHpyrJLa0
770
EbVtzsQhLn6rF+TzXnOlcipFvjsem3iYzCpuChfGQ6SovTcOjHV9z+hnpXvQ/fon
771
soVRZY65wKnF7IAoUwTmJS9opqgrN6kRgCd3DASAMd1bAkEA96SBVWFt/fJBNJ9H
772
tYnBKZGw0VeHOYmVYbvMSstssn8un+pQpUm9vlG/bp7Oxd/m+b9KWEh2xPfv6zqU
773
avNwHwJBANqzGZa/EpzF4J8pGti7oIAPUIDGMtfIcmqNXVMckrmzQ2vTfqtkEZsA
774
4rE1IERRyiJQx6EJsz21wJmGV9WJQ5kCQQDwkS0uXqVdFzgHO6S++tjmjYcxwr3g
775
H0CoFYSgbddOT6miqRskOQF3DZVkJT3kyuBgU2zKygz52ukQZMqxCb1fAkASvuTv
776
qfpH87Qq5kQhNKdbbwbmd2NxlNabazPijWuphGTdW0VfJdWfklyS2Kr+iqrs/5wV
777
HhathJt636Eg7oIjAkA8ht3MQ+XSl9yIJIS8gVpbPxSw5OMfw0PjVE7tBdQruiSc
778
nvuQES5C9BMHjF39LZiGH1iLQy7FgdHyoP+eodI7
779
-----END RSA PRIVATE KEY-----
783
class SocketListener(threading.Thread):
785
def __init__(self, callback):
786
threading.Thread.__init__(self)
787
self._callback = callback
788
self._socket = socket.socket()
789
self._socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
790
self._socket.bind(('localhost', 0))
791
self._socket.listen(1)
792
self.port = self._socket.getsockname()[1]
793
self._stop_event = threading.Event()
796
# called from outside this thread
797
self._stop_event.set()
798
# use a timeout here, because if the test fails, the server thread may
799
# never notice the stop_event.
805
readable, writable_unused, exception_unused = \
806
select.select([self._socket], [], [], 0.1)
807
if self._stop_event.isSet():
809
if len(readable) == 0:
812
s, addr_unused = self._socket.accept()
813
# because the loopback socket is inline, and transports are
814
# never explicitly closed, best to launch a new thread.
815
threading.Thread(target=self._callback, args=(s,)).start()
816
except socket.error, x:
817
sys.excepthook(*sys.exc_info())
818
warning('Socket error during accept() within unit test server'
821
# probably a failed test; unit test thread will log the
823
sys.excepthook(*sys.exc_info())
824
warning('Exception from within unit test server thread: %r' %
828
class SocketDelay(object):
829
"""A socket decorator to make TCP appear slower.
831
This changes recv, send, and sendall to add a fixed latency to each python
832
call if a new roundtrip is detected. That is, when a recv is called and the
833
flag new_roundtrip is set, latency is charged. Every send and send_all
836
In addition every send, sendall and recv sleeps a bit per character send to
839
Not all methods are implemented, this is deliberate as this class is not a
840
replacement for the builtin sockets layer. fileno is not implemented to
841
prevent the proxy being bypassed.
845
_proxied_arguments = dict.fromkeys([
846
"close", "getpeername", "getsockname", "getsockopt", "gettimeout",
847
"setblocking", "setsockopt", "settimeout", "shutdown"])
849
def __init__(self, sock, latency, bandwidth=1.0,
852
:param bandwith: simulated bandwith (MegaBit)
853
:param really_sleep: If set to false, the SocketDelay will just
854
increase a counter, instead of calling time.sleep. This is useful for
855
unittesting the SocketDelay.
858
self.latency = latency
859
self.really_sleep = really_sleep
860
self.time_per_byte = 1 / (bandwidth / 8.0 * 1024 * 1024)
861
self.new_roundtrip = False
864
if self.really_sleep:
867
SocketDelay.simulated_time += s
869
def __getattr__(self, attr):
870
if attr in SocketDelay._proxied_arguments:
871
return getattr(self.sock, attr)
872
raise AttributeError("'SocketDelay' object has no attribute %r" %
876
return SocketDelay(self.sock.dup(), self.latency, self.time_per_byte,
879
def recv(self, *args):
880
data = self.sock.recv(*args)
881
if data and self.new_roundtrip:
882
self.new_roundtrip = False
883
self.sleep(self.latency)
884
self.sleep(len(data) * self.time_per_byte)
887
def sendall(self, data, flags=0):
888
if not self.new_roundtrip:
889
self.new_roundtrip = True
890
self.sleep(self.latency)
891
self.sleep(len(data) * self.time_per_byte)
892
return self.sock.sendall(data, flags)
894
def send(self, data, flags=0):
895
if not self.new_roundtrip:
896
self.new_roundtrip = True
897
self.sleep(self.latency)
898
bytes_sent = self.sock.send(data, flags)
899
self.sleep(bytes_sent * self.time_per_byte)
903
class SFTPServer(Server):
904
"""Common code for SFTP server facilities."""
906
def __init__(self, server_interface=StubServer):
907
self._original_vendor = None
909
self._server_homedir = None
910
self._listener = None
912
self._vendor = ssh.ParamikoVendor()
913
self._server_interface = server_interface
918
def _get_sftp_url(self, path):
919
"""Calculate an sftp url to this server for path."""
920
return 'sftp://foo:bar@localhost:%d/%s' % (self._listener.port, path)
922
def log(self, message):
923
"""StubServer uses this to log when a new server is created."""
924
self.logs.append(message)
926
def _run_server_entry(self, sock):
927
"""Entry point for all implementations of _run_server.
929
If self.add_latency is > 0.000001 then sock is given a latency adding
932
if self.add_latency > 0.000001:
933
sock = SocketDelay(sock, self.add_latency)
934
return self._run_server(sock)
936
def _run_server(self, s):
937
ssh_server = paramiko.Transport(s)
938
key_file = pathjoin(self._homedir, 'test_rsa.key')
939
f = open(key_file, 'w')
940
f.write(STUB_SERVER_KEY)
942
host_key = paramiko.RSAKey.from_private_key_file(key_file)
943
ssh_server.add_server_key(host_key)
944
server = self._server_interface(self)
945
ssh_server.set_subsystem_handler('sftp', paramiko.SFTPServer,
946
StubSFTPServer, root=self._root,
947
home=self._server_homedir)
948
event = threading.Event()
949
ssh_server.start_server(event, server)
952
def setUp(self, backing_server=None):
953
# XXX: TODO: make sftpserver back onto backing_server rather than local
955
assert (backing_server is None or
956
isinstance(backing_server, local.LocalURLServer)), (
957
"backing_server should not be %r, because this can only serve the "
958
"local current working directory." % (backing_server,))
959
self._original_vendor = ssh._ssh_vendor_manager._cached_ssh_vendor
960
ssh._ssh_vendor_manager._cached_ssh_vendor = self._vendor
961
if sys.platform == 'win32':
962
# Win32 needs to use the UNICODE api
963
self._homedir = getcwd()
965
# But Linux SFTP servers should just deal in bytestreams
966
self._homedir = os.getcwd()
967
if self._server_homedir is None:
968
self._server_homedir = self._homedir
970
if sys.platform == 'win32':
972
self._listener = SocketListener(self._run_server_entry)
973
self._listener.setDaemon(True)
974
self._listener.start()
977
"""See bzrlib.transport.Server.tearDown."""
978
self._listener.stop()
979
ssh._ssh_vendor_manager._cached_ssh_vendor = self._original_vendor
981
def get_bogus_url(self):
982
"""See bzrlib.transport.Server.get_bogus_url."""
983
# this is chosen to try to prevent trouble with proxies, wierd dns, etc
984
# we bind a random socket, so that we get a guaranteed unused port
985
# we just never listen on that port
987
s.bind(('localhost', 0))
988
return 'sftp://%s:%s/' % s.getsockname()
991
class SFTPFullAbsoluteServer(SFTPServer):
992
"""A test server for sftp transports, using absolute urls and ssh."""
995
"""See bzrlib.transport.Server.get_url."""
996
homedir = self._homedir
997
if sys.platform != 'win32':
998
# Remove the initial '/' on all platforms but win32
999
homedir = homedir[1:]
1000
return self._get_sftp_url(urlutils.escape(homedir))
1003
class SFTPServerWithoutSSH(SFTPServer):
1004
"""An SFTP server that uses a simple TCP socket pair rather than SSH."""
1007
super(SFTPServerWithoutSSH, self).__init__()
1008
self._vendor = ssh.LoopbackVendor()
1010
def _run_server(self, sock):
1011
# Re-import these as locals, so that they're still accessible during
1012
# interpreter shutdown (when all module globals get set to None, leading
1013
# to confusing errors like "'NoneType' object has no attribute 'error'".
1014
class FakeChannel(object):
1015
def get_transport(self):
1017
def get_log_channel(self):
1021
def get_hexdump(self):
1026
server = paramiko.SFTPServer(FakeChannel(), 'sftp', StubServer(self), StubSFTPServer,
1027
root=self._root, home=self._server_homedir)
1029
server.start_subsystem('sftp', None, sock)
1030
except socket.error, e:
1031
if (len(e.args) > 0) and (e.args[0] == errno.EPIPE):
1032
# it's okay for the client to disconnect abruptly
1033
# (bug in paramiko 1.6: it should absorb this exception)
1037
except Exception, e:
1038
# This typically seems to happen during interpreter shutdown, so
1039
# most of the useful ways to report this error are won't work.
1040
# Writing the exception type, and then the text of the exception,
1041
# seems to be the best we can do.
1043
sys.stderr.write('\nEXCEPTION %r: ' % (e.__class__,))
1044
sys.stderr.write('%s\n\n' % (e,))
1045
server.finish_subsystem()
1048
class SFTPAbsoluteServer(SFTPServerWithoutSSH):
1049
"""A test server for sftp transports, using absolute urls."""
1052
"""See bzrlib.transport.Server.get_url."""
1053
homedir = self._homedir
1054
if sys.platform != 'win32':
1055
# Remove the initial '/' on all platforms but win32
1056
homedir = homedir[1:]
1057
return self._get_sftp_url(urlutils.escape(homedir))
1060
class SFTPHomeDirServer(SFTPServerWithoutSSH):
1061
"""A test server for sftp transports, using homedir relative urls."""
1064
"""See bzrlib.transport.Server.get_url."""
1065
return self._get_sftp_url("~/")
1068
class SFTPSiblingAbsoluteServer(SFTPAbsoluteServer):
1069
"""A test server for sftp transports where only absolute paths will work.
1071
It does this by serving from a deeply-nested directory that doesn't exist.
1074
def setUp(self, backing_server=None):
1075
self._server_homedir = '/dev/noone/runs/tests/here'
1076
super(SFTPSiblingAbsoluteServer, self).setUp(backing_server)
908
1079
def get_test_permutations():
909
1080
"""Return the permutations to be used in testing."""
910
from bzrlib.tests import stub_sftp
911
return [(SFTPTransport, stub_sftp.SFTPAbsoluteServer),
912
(SFTPTransport, stub_sftp.SFTPHomeDirServer),
913
(SFTPTransport, stub_sftp.SFTPSiblingAbsoluteServer),
1081
return [(SFTPTransport, SFTPAbsoluteServer),
1082
(SFTPTransport, SFTPHomeDirServer),
1083
(SFTPTransport, SFTPSiblingAbsoluteServer),
added
removed
bzrlib/transport/sftp.py
