1
# Copyright (C) 2005-2010 Canonical Ltd
3
# This program is free software; you can redistribute it and/or modify
4
# it under the terms of the GNU General Public License as published by
5
# the Free Software Foundation; either version 2 of the License, or
6
# (at your option) any later version.
8
# This program is distributed in the hope that it will be useful,
9
# but WITHOUT ANY WARRANTY; without even the implied warranty of
10
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11
# GNU General Public License for more details.
13
# You should have received a copy of the GNU General Public License
14
# along with this program; if not, write to the Free Software
15
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17
"""Abstraction for interacting with the user.
19
Applications can choose different types of UI, and they deal with displaying
20
messages or progress to the user, and with gathering different types of input.
22
Several levels are supported, and you can also register new factories such as
26
Semi-abstract base class
28
bzrlib.ui.SilentUIFactory
29
Produces no output and cannot take any input; useful for programs using
30
bzrlib in batch mode or for programs such as loggerhead.
32
bzrlib.ui.CannedInputUIFactory
33
For use in testing; the input values to be returned are provided
36
bzrlib.ui.text.TextUIFactory
37
Standard text command-line interface, with stdin, stdout, stderr.
38
May make more or less advanced use of them, eg in drawing progress bars,
39
depending on the detected capabilities of the terminal.
40
GUIs may choose to subclass this so that unimplemented methods fall
41
back to working through the terminal.
49
from bzrlib.lazy_import import lazy_import
50
lazy_import(globals(), """
60
from bzrlib.symbol_versioning import (
67
_valid_boolean_strings = dict(yes=True, no=False,
70
true=True, false=False)
71
_valid_boolean_strings['1'] = True
72
_valid_boolean_strings['0'] = False
75
def bool_from_string(s, accepted_values=None):
76
"""Returns a boolean if the string can be interpreted as such.
78
Interpret case insensitive strings as booleans. The default values
79
includes: 'yes', 'no, 'y', 'n', 'true', 'false', '0', '1', 'on',
80
'off'. Alternative values can be provided with the 'accepted_values'
83
:param s: A string that should be interpreted as a boolean. It should be of
84
type string or unicode.
86
:param accepted_values: An optional dict with accepted strings as keys and
87
True/False as values. The strings will be tested against a lowered
90
:return: True or False for accepted strings, None otherwise.
92
if accepted_values is None:
93
accepted_values = _valid_boolean_strings
95
if type(s) in (str, unicode):
97
val = accepted_values[s.lower()]
103
class UIFactory(object):
106
This tells the library how to display things to the user. Through this
107
layer different applications can choose the style of UI.
111
self._task_stack = []
113
def get_password(self, prompt='', **kwargs):
114
"""Prompt the user for a password.
116
:param prompt: The prompt to present the user
117
:param kwargs: Arguments which will be expanded into the prompt.
118
This lets front ends display different things if
121
:return: The password string, return None if the user canceled the
122
request. Note that we do not touch the encoding, users may
123
have whatever they see fit and the password should be
126
raise NotImplementedError(self.get_password)
128
def make_output_stream(self, encoding=None, encoding_type=None):
129
"""Get a stream for sending out bulk text data.
131
This is used for commands that produce bulk text, such as log or diff
132
output, as opposed to user interaction. This should work even for
133
non-interactive user interfaces. Typically this goes to a decorated
134
version of stdout, but in a GUI it might be appropriate to send it to a
135
window displaying the text.
137
:param encoding: Unicode encoding for output; default is the
138
terminal encoding, which may be different from the user encoding.
139
(See get_terminal_encoding.)
141
:param encoding_type: How to handle encoding errors:
142
replace/strict/escape/exact. Default is replace.
144
# XXX: is the caller supposed to close the resulting object?
146
encoding = osutils.get_terminal_encoding()
147
if encoding_type is None:
148
encoding_type = 'replace'
149
out_stream = self._make_output_stream_explicit(encoding, encoding_type)
152
def _make_output_stream_explicit(self, encoding, encoding_type):
153
raise NotImplementedError("%s doesn't support make_output_stream"
154
% (self.__class__.__name__))
156
def nested_progress_bar(self):
157
"""Return a nested progress bar.
159
When the bar has been finished with, it should be released by calling
163
t = progress.ProgressTask(self._task_stack[-1], self)
165
t = progress.ProgressTask(None, self)
166
self._task_stack.append(t)
169
def _progress_finished(self, task):
170
"""Called by the ProgressTask when it finishes"""
171
if not self._task_stack:
172
warnings.warn("%r finished but nothing is active"
174
elif task != self._task_stack[-1]:
175
warnings.warn("%r is not the active task %r"
176
% (task, self._task_stack[-1]))
178
del self._task_stack[-1]
179
if not self._task_stack:
180
self._progress_all_finished()
182
def _progress_all_finished(self):
183
"""Called when the top-level progress task finished"""
186
def _progress_updated(self, task):
187
"""Called by the ProgressTask when it changes.
189
Should be specialized to draw the progress.
193
def clear_term(self):
194
"""Prepare the terminal for output.
196
This will, for example, clear text progress bars, and leave the
197
cursor at the leftmost position.
201
def get_boolean(self, prompt):
202
"""Get a boolean question answered from the user.
204
:param prompt: a message to prompt the user with. Should be a single
205
line without terminating \n.
206
:return: True or False for y/yes or n/no.
208
raise NotImplementedError(self.get_boolean)
210
def get_integer(self, prompt):
211
"""Get an integer from the user.
213
:param prompt: a message to prompt the user with. Could be a multi-line
214
prompt but without a terminating \n.
216
:return: A signed integer.
218
raise NotImplementedError(self.get_integer)
220
def make_progress_view(self):
221
"""Construct a new ProgressView object for this UI.
223
Application code should normally not call this but instead
224
nested_progress_bar().
226
return NullProgressView()
228
def recommend_upgrade(self,
231
# this should perhaps be in the TextUIFactory and the default can do
233
trace.warning("%s is deprecated "
234
"and a better format is available.\n"
235
"It is recommended that you upgrade by "
236
"running the command\n"
241
def report_transport_activity(self, transport, byte_count, direction):
242
"""Called by transports as they do IO.
244
This may update a progress bar, spinner, or similar display.
245
By default it does nothing.
249
def log_transport_activity(self, display=False):
250
"""Write out whatever transport activity has been measured.
252
Implementations are allowed to do nothing, but it is useful if they can
253
write a line to the log file.
255
:param display: If False, only log to disk, if True also try to display
256
a message to the user.
259
# Default implementation just does nothing
262
def show_error(self, msg):
263
"""Show an error message (not an exception) to the user.
265
The message should not have an error prefix or trailing newline. That
266
will be added by the factory if appropriate.
268
raise NotImplementedError(self.show_error)
270
def show_message(self, msg):
271
"""Show a message to the user."""
272
raise NotImplementedError(self.show_message)
274
def show_warning(self, msg):
275
"""Show a warning to the user."""
276
raise NotImplementedError(self.show_warning)
280
class SilentUIFactory(UIFactory):
281
"""A UI Factory which never prints anything.
283
This is the default UI, if another one is never registered by a program
284
using bzrlib, and it's also active for example inside 'bzr serve'.
286
Methods that try to read from the user raise an error; methods that do
291
UIFactory.__init__(self)
296
def get_username(self, prompt, **kwargs):
299
def _make_output_stream_explicit(self, encoding, encoding_type):
300
return NullOutputStream(encoding)
302
def show_error(self, msg):
305
def show_message(self, msg):
308
def show_warning(self, msg):
312
class CannedInputUIFactory(SilentUIFactory):
313
"""A silent UI that return canned input."""
315
def __init__(self, responses):
316
self.responses = responses
319
return "%s(%r)" % (self.__class__.__name__, self.responses)
321
def get_boolean(self, prompt):
322
return self.responses.pop(0)
324
def get_integer(self, prompt):
325
return self.responses.pop(0)
327
def get_password(self, prompt='', **kwargs):
328
return self.responses.pop(0)
330
def get_username(self, prompt, **kwargs):
331
return self.responses.pop(0)
333
def assert_all_input_consumed(self):
335
raise AssertionError("expected all input in %r to be consumed"
339
ui_factory = SilentUIFactory()
340
# IMPORTANT: never import this symbol directly. ONLY ever access it as
341
# ui.ui_factory, so that you refer to the current value.
344
def make_ui_for_terminal(stdin, stdout, stderr):
345
"""Construct and return a suitable UIFactory for a text mode program.
347
# this is now always TextUIFactory, which in turn decides whether it
348
# should display progress bars etc
349
from bzrlib.ui.text import TextUIFactory
350
return TextUIFactory(stdin, stdout, stderr)
353
class NullProgressView(object):
354
"""Soak up and ignore progress information."""
359
def show_progress(self, task):
362
def show_transport_activity(self, transport, direction, byte_count):
365
def log_transport_activity(self, display=False):
369
class NullOutputStream(object):
370
"""Acts like a file, but discard all output."""
372
def __init__(self, encoding):
373
self.encoding = encoding
375
def write(self, data):
378
def writelines(self, data):
added
removed
bzrlib/ui/__init__.py
