1
# Copyright (C) 2005, 2006, 2007, 2008, 2009 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 user encoding.
139
:param encoding_type: How to handle encoding errors:
140
replace/strict/escape/exact. Default is replace.
142
# XXX: is the caller supposed to close the resulting object?
144
encoding = osutils.get_user_encoding()
145
if encoding_type is None:
146
encoding_type = 'replace'
147
# For whatever reason codecs.getwriter() does not advertise its encoding
148
# it just returns the encoding of the wrapped file, which is completely
149
# bogus. So set the attribute, so we can find the correct encoding later.
150
out_stream = self._make_output_stream_explicit(encoding, encoding_type)
151
if not getattr(out_stream, 'encoding', None):
152
out_stream.encoding = encoding
155
def _make_output_stream_explicit(self, encoding, encoding_type):
156
raise NotImplementedError("%s doesn't support make_output_stream"
157
% (self.__class__.__name__))
159
def nested_progress_bar(self):
160
"""Return a nested progress bar.
162
When the bar has been finished with, it should be released by calling
166
t = progress.ProgressTask(self._task_stack[-1], self)
168
t = progress.ProgressTask(None, self)
169
self._task_stack.append(t)
172
def _progress_finished(self, task):
173
"""Called by the ProgressTask when it finishes"""
174
if not self._task_stack:
175
warnings.warn("%r finished but nothing is active"
177
elif task != self._task_stack[-1]:
178
warnings.warn("%r is not the active task %r"
179
% (task, self._task_stack[-1]))
181
del self._task_stack[-1]
182
if not self._task_stack:
183
self._progress_all_finished()
185
def _progress_all_finished(self):
186
"""Called when the top-level progress task finished"""
189
def _progress_updated(self, task):
190
"""Called by the ProgressTask when it changes.
192
Should be specialized to draw the progress.
196
def clear_term(self):
197
"""Prepare the terminal for output.
199
This will, for example, clear text progress bars, and leave the
200
cursor at the leftmost position.
204
def get_boolean(self, prompt):
205
"""Get a boolean question answered from the user.
207
:param prompt: a message to prompt the user with. Should be a single
208
line without terminating \n.
209
:return: True or False for y/yes or n/no.
211
raise NotImplementedError(self.get_boolean)
213
def make_progress_view(self):
214
"""Construct a new ProgressView object for this UI.
216
Application code should normally not call this but instead
217
nested_progress_bar().
219
return NullProgressView()
221
def recommend_upgrade(self,
224
# this should perhaps be in the TextUIFactory and the default can do
226
trace.warning("%s is deprecated "
227
"and a better format is available.\n"
228
"It is recommended that you upgrade by "
229
"running the command\n"
234
def report_transport_activity(self, transport, byte_count, direction):
235
"""Called by transports as they do IO.
237
This may update a progress bar, spinner, or similar display.
238
By default it does nothing.
242
def show_error(self, msg):
243
"""Show an error message (not an exception) to the user.
245
The message should not have an error prefix or trailing newline. That
246
will be added by the factory if appropriate.
248
raise NotImplementedError(self.show_error)
250
def show_message(self, msg):
251
"""Show a message to the user."""
252
raise NotImplementedError(self.show_message)
254
def show_warning(self, msg):
255
"""Show a warning to the user."""
256
raise NotImplementedError(self.show_warning)
260
class SilentUIFactory(UIFactory):
261
"""A UI Factory which never prints anything.
263
This is the default UI, if another one is never registered by a program
264
using bzrlib, and it's also active for example inside 'bzr serve'.
266
Methods that try to read from the user raise an error; methods that do
271
UIFactory.__init__(self)
276
def get_username(self, prompt, **kwargs):
279
def show_error(self, msg):
282
def show_message(self, msg):
285
def show_warning(self, msg):
289
class CannedInputUIFactory(SilentUIFactory):
290
"""A silent UI that return canned input."""
292
def __init__(self, responses):
293
self.responses = responses
296
return "%s(%r)" % (self.__class__.__name__, self.responses)
298
def get_boolean(self, prompt):
299
return self.responses.pop(0)
301
def get_password(self, prompt='', **kwargs):
302
return self.responses.pop(0)
304
def get_username(self, prompt, **kwargs):
305
return self.responses.pop(0)
307
def assert_all_input_consumed(self):
309
raise AssertionError("expected all input in %r to be consumed"
313
ui_factory = SilentUIFactory()
314
# IMPORTANT: never import this symbol directly. ONLY ever access it as
315
# ui.ui_factory, so that you refer to the current value.
318
def make_ui_for_terminal(stdin, stdout, stderr):
319
"""Construct and return a suitable UIFactory for a text mode program.
321
# this is now always TextUIFactory, which in turn decides whether it
322
# should display progress bars etc
323
from bzrlib.ui.text import TextUIFactory
324
return TextUIFactory(stdin, stdout, stderr)
327
class NullProgressView(object):
328
"""Soak up and ignore progress information."""
333
def show_progress(self, task):
336
def show_transport_activity(self, transport, direction, byte_count):