14
14
# along with this program; if not, write to the Free Software
15
15
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17
"""bzr python plugin support.
19
When load_plugins() is invoked, any python module in any directory in
20
$BRZ_PLUGIN_PATH will be imported. The module will be imported as
21
'breezy.plugins.$BASENAME(PLUGIN)'. In the plugin's main body, it should
22
update any breezy registries it wants to extend.
17
"""Breezy plugin support.
19
Which plugins to load can be configured by setting these environment variables:
21
- BRZ_PLUGIN_PATH: Paths to look for plugins in.
22
- BRZ_DISABLE_PLUGINS: Plugin names to block from being loaded.
23
- BRZ_PLUGINS_AT: Name and paths for plugins to load from specific locations.
25
The interfaces this module exports include:
27
- disable_plugins: Load no plugins and stop future automatic loading.
28
- load_plugins: Load all plugins that can be found in configuration.
29
- describe_plugins: Generate text for each loaded (or failed) plugin.
30
- extend_path: Mechanism by which the plugins package path is set.
31
- plugin_name: Gives unprefixed name of a plugin module.
24
33
See the plugin-api developer documentation for information about writing
27
BRZ_PLUGIN_PATH is also honoured for any plugins imported via
28
'import breezy.plugins.PLUGINNAME', as long as set_plugins_path has been
32
37
from __future__ import absolute_import
37
44
from . import osutils
39
46
from .lazy_import import lazy_import
40
47
lazy_import(globals(), """
50
from importlib import util as importlib_util
45
52
from breezy import (
46
_format_version_tuple,
52
from breezy.i18n import gettext
53
from breezy import plugins as _mod_plugins
57
DEFAULT_PLUGIN_PATH = None
59
_plugins_disabled = False
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# Map from plugin name, to list of string warnings about eg plugin
67
def are_plugins_disabled():
68
return _plugins_disabled
71
def disable_plugins():
62
_MODULE_PREFIX = "breezy.plugins."
64
if __debug__ or sys.version_info > (3,):
70
def disable_plugins(state=None):
72
71
"""Disable loading plugins.
74
73
Future calls to load_plugins() will be ignored.
76
global _plugins_disabled
77
_plugins_disabled = True
81
def describe_plugins(show_paths=False):
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:param state: The library state object that records loaded plugins.
78
state = breezy.global_state
82
def load_plugins(path=None, state=None):
83
"""Load breezy plugins.
85
The environment variable BRZ_PLUGIN_PATH is considered a delimited
86
set of paths to look through. Each entry is searched for `*.py`
87
files (and whatever other extensions are used in the platform,
90
:param path: The list of paths to search for plugins. By default,
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it is populated from the __path__ of the breezy.plugins package.
92
:param state: The library state object that records loaded plugins.
95
state = breezy.global_state
96
if getattr(state, 'plugins', None) is not None:
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# People can make sure plugins are loaded, they just won't be twice
101
# Calls back into extend_path() here
102
from breezy.plugins import __path__ as path
104
state.plugin_warnings = {}
105
_load_plugins(state, path)
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state.plugins = plugins()
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def plugin_name(module_name):
110
"""Gives unprefixed name from module_name or None."""
111
if module_name.startswith(_MODULE_PREFIX):
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parts = module_name.split(".")
118
def extend_path(path, name):
119
"""Helper so breezy.plugins can be a sort of namespace package.
121
To be used in similar fashion to pkgutil.extend_path:
123
from breezy.plugins import extend_path
124
__path__ = extend_path(__path__, __name__)
126
Inspects the BRZ_PLUGIN* envvars, sys.path, and the filesystem to find
127
plugins. May mutate sys.modules in order to block plugin loading, and may
128
append a new meta path finder to sys.meta_path for plugins@ loading.
130
Returns a list of paths to import from, as an enhanced object that also
131
contains details of the other configuration used.
133
blocks = _env_disable_plugins()
134
_block_plugins(blocks)
136
extra_details = _env_plugins_at()
137
_install_importer_if_needed(extra_details)
139
paths = _iter_plugin_paths(_env_plugin_path(), path)
141
return _Path(name, blocks, extra_details, paths)
145
"""List type to use as __path__ but containing additional details.
147
Python 3 allows any iterable for __path__ but Python 2 is more fussy.
150
def __init__(self, package_name, blocked, extra, paths):
151
super(_Path, self).__init__(paths)
152
self.package_name = package_name
153
self.blocked_names = blocked
154
self.extra_details = extra
157
return "%s(%r, %r, %r, %s)" % (
158
self.__class__.__name__, self.package_name, self.blocked_names,
159
self.extra_details, list.__repr__(self))
162
def _expect_identifier(name, env_key, env_value):
163
"""Validate given name from envvar is usable as a Python identifier.
165
Returns the name as a native str, or None if it was invalid.
167
Per PEP 3131 this is no longer strictly correct for Python 3, but as MvL
168
didn't include a neat way to check except eval, this enforces ascii.
170
if re.match(r"^[A-Za-z_][A-Za-z0-9_]*$", name) is None:
171
trace.warning("Invalid name '%s' in %s='%s'", name, env_key, env_value)
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def _env_disable_plugins(key='BRZ_DISABLE_PLUGINS'):
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"""Gives list of names for plugins to disable from environ key."""
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env = osutils.path_from_environ(key)
181
for name in env.split(os.pathsep):
182
name = _expect_identifier(name, key, env)
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disabled_names.append(name)
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return disabled_names
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def _env_plugins_at(key='BRZ_PLUGINS_AT'):
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"""Gives list of names and paths of specific plugins from environ key."""
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env = osutils.path_from_environ(key)
193
for pair in env.split(os.pathsep):
195
name, path = pair.split('@', 1)
198
name = osutils.basename(path).split('.', 1)[0]
199
name = _expect_identifier(name, key, env)
201
plugin_details.append((name, path))
202
return plugin_details
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def _env_plugin_path(key='BRZ_PLUGIN_PATH'):
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"""Gives list of paths and contexts for plugins from environ key.
208
Each entry is either a specific path to load plugins from and the value
209
'path', or None and one of the three values 'user', 'core', 'site'.
212
env = osutils.path_from_environ(key)
213
defaults = {"user": not env, "core": True, "site": True}
215
# Add paths specified by user in order
216
for p in env.split(os.pathsep):
217
flag, name = p[:1], p[1:]
218
if flag in ("+", "-") and name in defaults:
219
if flag == "+" and defaults[name] is not None:
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path_details.append((None, name))
221
defaults[name] = None
223
path_details.append((p, 'path'))
225
# Add any remaining default paths
226
for name in ('user', 'core', 'site'):
228
path_details.append((None, name))
233
def _iter_plugin_paths(paths_from_env, core_paths):
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"""Generate paths using paths_from_env and core_paths."""
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# GZ 2017-06-02: This is kinda horrid, should make better.
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for path, context in paths_from_env:
237
if context == 'path':
239
elif context == 'user':
240
path = get_user_plugin_path()
241
if os.path.isdir(path):
243
elif context == 'core':
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for path in _get_core_plugin_paths(core_paths):
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elif context == 'site':
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for path in _get_site_plugin_paths(sys.path):
248
if os.path.isdir(path):
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def _install_importer_if_needed(plugin_details):
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"""Install a meta path finder to handle plugin_details if any."""
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finder = _PluginsAtFinder(_MODULE_PREFIX, plugin_details)
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# For Python 3, must insert before default PathFinder to override.
257
sys.meta_path.insert(2, finder)
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def _load_plugins(state, paths):
261
"""Do the importing all plugins from paths."""
262
imported_names = set()
263
for name, path in _iter_possible_plugins(paths):
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if name not in imported_names:
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msg = _load_plugin_module(name, path)
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state.plugin_warnings.setdefault(name, []).append(msg)
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imported_names.add(name)
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def _block_plugins(names):
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"""Add names to sys.modules to block future imports."""
274
package_name = _MODULE_PREFIX + name
275
if sys.modules.get(package_name) is not None:
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trace.mutter("Blocked plugin %s already loaded.", name)
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sys.modules[package_name] = None
280
def _get_package_init(package_path):
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"""Get path of __init__ file from package_path or None if not a package."""
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init_path = osutils.pathjoin(package_path, "__init__.py")
283
if os.path.exists(init_path):
285
init_path = init_path[:-3] + COMPILED_EXT
286
if os.path.exists(init_path):
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def _iter_possible_plugins(plugin_paths):
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"""Generate names and paths of possible plugins from plugin_paths."""
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# Inspect any from BRZ_PLUGINS_AT first.
294
for name, path in getattr(plugin_paths, "extra_details", ()):
296
# Then walk over files and directories in the paths from the package.
297
for path in plugin_paths:
298
if os.path.isfile(path):
299
if path.endswith(".zip"):
300
trace.mutter("Don't yet support loading plugins from zip.")
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for name, path in _walk_modules(path):
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def _walk_modules(path):
307
"""Generate name and path of modules and packages on path."""
308
for root, dirs, files in os.walk(path):
312
if f.endswith((".py", COMPILED_EXT)):
313
yield f.rsplit(".", 1)[0], root
317
package_dir = osutils.pathjoin(root, d)
318
fullpath = _get_package_init(package_dir)
319
if fullpath is not None:
321
# Don't descend into subdirectories
325
def describe_plugins(show_paths=False, state=None):
82
326
"""Generate text description of plugins.
84
Includes both those that have loaded, and those that failed to
328
Includes both those that have loaded, and those that failed to load.
87
:param show_paths: If true,
330
:param show_paths: If true, include the plugin path.
331
:param state: The library state object to inspect.
88
332
:returns: Iterator of text lines (including newlines.)
90
from inspect import getdoc
91
loaded_plugins = plugins()
92
all_names = sorted(list(set(
93
loaded_plugins.keys() + plugin_warnings.keys())))
335
state = breezy.global_state
336
all_names = sorted(set(state.plugins).union(state.plugin_warnings))
94
337
for name in all_names:
95
if name in loaded_plugins:
96
plugin = loaded_plugins[name]
338
if name in state.plugins:
339
plugin = state.plugins[name]
97
340
version = plugin.__version__
98
341
if version == 'unknown':
100
343
yield '%s %s\n' % (name, version)
101
d = getdoc(plugin.module)
344
d = plugin.module.__doc__
103
346
doc = d.split('\n')[0]
106
349
yield (" %s\n" % doc)
108
351
yield (" %s\n" % plugin.path())
111
353
yield "%s (failed to load)\n" % name
112
if name in plugin_warnings:
113
for line in plugin_warnings[name]:
354
if name in state.plugin_warnings:
355
for line in state.plugin_warnings[name]:
114
356
yield " ** " + line + '\n'
118
def _strip_trailing_sep(path):
119
return path.rstrip("\\/")
122
def _get_specific_plugin_paths(paths):
123
"""Returns the plugin paths from a string describing the associations.
125
:param paths: A string describing the paths associated with the plugins.
127
:returns: A list of (plugin name, path) tuples.
129
For example, if paths is my_plugin@/test/my-test:her_plugin@/production/her,
130
[('my_plugin', '/test/my-test'), ('her_plugin', '/production/her')]
133
Note that ':' in the example above depends on the os.
138
for spec in paths.split(os.pathsep):
140
name, path = spec.split('@')
142
raise errors.BzrCommandError(gettext(
143
'"%s" is not a valid <plugin_name>@<plugin_path> description ')
145
specs.append((name, path))
149
def set_plugins_path(path=None):
150
"""Set the path for plugins to be loaded from.
152
:param path: The list of paths to search for plugins. By default,
153
path will be determined using get_standard_plugins_path.
154
if path is [], no plugins can be loaded.
157
path = get_standard_plugins_path()
158
_mod_plugins.__path__ = path
159
PluginImporter.reset()
160
# Set up a blacklist for disabled plugins
161
disabled_plugins = os.environ.get('BRZ_DISABLE_PLUGINS', None)
162
if disabled_plugins is not None:
163
for name in disabled_plugins.split(os.pathsep):
164
PluginImporter.blacklist.add('breezy.plugins.' + name)
165
# Set up a the specific paths for plugins
166
for plugin_name, plugin_path in _get_specific_plugin_paths(os.environ.get(
167
'BRZ_PLUGINS_AT', None)):
168
PluginImporter.specific_paths[
169
'breezy.plugins.%s' % plugin_name] = plugin_path
173
def _append_new_path(paths, new_path):
174
"""Append a new path if it set and not already known."""
175
if new_path is not None and new_path not in paths:
176
paths.append(new_path)
180
def get_core_plugin_path():
182
brz_exe = bool(getattr(sys, 'frozen', None))
183
if brz_exe: # expand path for brz.exe
360
def _get_core_plugin_paths(existing_paths):
361
"""Generate possible locations for plugins based on existing_paths."""
362
if getattr(sys, 'frozen', False):
184
363
# We need to use relative path to system-wide plugin
185
364
# directory because breezy from standalone brz.exe
186
365
# could be imported by another standalone program
191
370
# then plugins directory is
192
371
# C:\Program Files\Bazaar\plugins
193
372
# so relative path is ../../../plugins
194
core_path = osutils.abspath(osutils.pathjoin(
195
osutils.dirname(__file__), '../../../plugins'))
373
yield osutils.abspath(osutils.pathjoin(
374
osutils.dirname(__file__), '../../../plugins'))
196
375
else: # don't look inside library.zip
197
# search the plugin path before the breezy installed dir
198
core_path = os.path.dirname(_mod_plugins.__file__)
202
def get_site_plugin_path():
203
"""Returns the path for the site installed plugins."""
204
if sys.platform == 'win32':
205
# We don't have (yet) a good answer for windows since that is certainly
206
# related to the way we build the installers. -- vila20090821
210
from distutils.sysconfig import get_python_lib
212
# If distutuils is not available, we just don't know where they are
215
site_path = osutils.pathjoin(get_python_lib(), 'breezy', 'plugins')
376
for path in existing_paths:
380
def _get_site_plugin_paths(sys_paths):
381
"""Generate possible locations for plugins from given sys_paths."""
382
for path in sys_paths:
383
if os.path.basename(path) in ('dist-packages', 'site-packages'):
384
yield osutils.pathjoin(path, 'breezy', 'plugins')
219
387
def get_user_plugin_path():
220
388
return osutils.pathjoin(config.config_dir(), 'plugins')
223
def get_standard_plugins_path():
224
"""Determine a plugin path suitable for general use."""
225
# Ad-Hoc default: core is not overriden by site but user can overrides both
226
# The rationale is that:
227
# - 'site' comes last, because these plugins should always be available and
228
# are supposed to be in sync with the brz installed on site.
229
# - 'core' comes before 'site' so that running brz from sources or a user
230
# installed version overrides the site version.
231
# - 'user' comes first, because... user is always right.
232
# - the above rules clearly defines which plugin version will be loaded if
233
# several exist. Yet, it is sometimes desirable to disable some directory
234
# so that a set of plugins is disabled as once. This can be done via
235
# -site, -core, -user.
237
env_paths = os.environ.get('BRZ_PLUGIN_PATH', '+user').split(os.pathsep)
238
defaults = ['+core', '+site']
240
# The predefined references
241
refs = dict(core=get_core_plugin_path(),
242
site=get_site_plugin_path(),
243
user=get_user_plugin_path())
245
# Unset paths that should be removed
246
for k,v in refs.items():
248
# defaults can never mention removing paths as that will make it
249
# impossible for the user to revoke these removals.
250
if removed in env_paths:
251
env_paths.remove(removed)
256
for p in env_paths + defaults:
257
if p.startswith('+'):
258
# Resolve references if they are known
262
# Leave them untouched so user can still use paths starting
265
_append_new_path(paths, p)
267
# Get rid of trailing slashes, since Python can't handle them when
268
# it tries to import modules.
269
paths = list(map(_strip_trailing_sep, paths))
273
def load_plugins(path=None):
274
"""Load breezy plugins.
276
The environment variable BRZ_PLUGIN_PATH is considered a delimited
277
set of paths to look through. Each entry is searched for `*.py`
278
files (and whatever other extensions are used in the platform,
281
load_from_path() provides the underlying mechanism and is called with
282
the default directory list to provide the normal behaviour.
284
:param path: The list of paths to search for plugins. By default,
285
path will be determined using get_standard_plugins_path.
286
if path is [], no plugins can be loaded.
290
# People can make sure plugins are loaded, they just won't be twice
294
# scan for all plugins in the path.
295
load_from_path(set_plugins_path(path))
298
def load_from_path(dirs):
299
"""Load breezy plugins found in each dir in dirs.
301
Loading a plugin means importing it into the python interpreter.
302
The plugin is expected to make calls to register commands when
303
it's loaded (or perhaps access other hooks in future.)
305
Plugins are loaded into breezy.plugins.NAME, and can be found there
306
for future reference.
308
The python module path for breezy.plugins will be modified to be 'dirs'.
310
# Explicitly load the plugins with a specific path
311
for fullname, path in PluginImporter.specific_paths.items():
312
name = fullname[len('breezy.plugins.'):]
313
_load_plugin_module(name, path)
315
# We need to strip the trailing separators here as well as in the
316
# set_plugins_path function because calling code can pass anything in to
317
# this function, and since it sets plugins.__path__, it should set it to
318
# something that will be valid for Python to use (in case people try to
319
# run "import breezy.plugins.PLUGINNAME" after calling this function).
320
_mod_plugins.__path__ = list(map(_strip_trailing_sep, dirs))
324
trace.mutter('looking for plugins in %s', d)
329
# backwards compatability: load_from_dirs was the old name
330
# This was changed in 0.15
331
load_from_dirs = load_from_path
334
def _find_plugin_module(dir, name):
335
"""Check if there is a valid python module that can be loaded as a plugin.
337
:param dir: The directory where the search is performed.
338
:param path: An existing file path, either a python file or a package
341
:return: (name, path, description) name is the module name, path is the
342
file to load and description is the tuple returned by
345
path = osutils.pathjoin(dir, name)
346
if os.path.isdir(path):
347
# Check for a valid __init__.py file, valid suffixes depends on -O and
348
# can be .py, .pyc and .pyo
349
for suffix, mode, kind in imp.get_suffixes():
350
if kind not in (imp.PY_SOURCE, imp.PY_COMPILED):
351
# We don't recognize compiled modules (.so, .dll, etc)
353
init_path = osutils.pathjoin(path, '__init__' + suffix)
354
if os.path.isfile(init_path):
355
return name, init_path, (suffix, mode, kind)
357
for suffix, mode, kind in imp.get_suffixes():
358
if name.endswith(suffix):
359
# Clean up the module name
360
name = name[:-len(suffix)]
361
if kind == imp.C_EXTENSION and name.endswith('module'):
362
name = name[:-len('module')]
363
return name, path, (suffix, mode, kind)
364
# There is no python module here
365
return None, None, (None, None, None)
368
def record_plugin_warning(plugin_name, warning_message):
391
def record_plugin_warning(warning_message):
369
392
trace.mutter(warning_message)
370
plugin_warnings.setdefault(plugin_name, []).append(warning_message)
393
return warning_message
373
396
def _load_plugin_module(name, dir):
374
"""Load plugin name from dir.
397
"""Load plugin by name.
376
399
:param name: The plugin name in the breezy.plugins namespace.
377
400
:param dir: The directory the plugin is loaded from for error messages.
379
if ('breezy.plugins.%s' % name) in PluginImporter.blacklist:
402
if _MODULE_PREFIX + name in sys.modules:
382
exec("import breezy.plugins.%s" % name, {})
383
except KeyboardInterrupt:
405
__import__(_MODULE_PREFIX + name)
385
406
except errors.IncompatibleAPI as e:
386
407
warning_message = (
387
408
"Unable to load plugin %r. It requested API version "
388
409
"%s of module %s but the minimum exported version is %s, and "
389
410
"the maximum is %s" %
390
411
(name, e.wanted, e.api, e.minimum, e.current))
391
record_plugin_warning(name, warning_message)
412
return record_plugin_warning(warning_message)
392
413
except Exception as e:
393
trace.warning("%s" % e)
414
trace.log_exception_quietly()
415
if 'error' in debug.debug_flags:
416
trace.print_exception(sys.exc_info(), sys.stderr)
417
# GZ 2017-06-02: Move this name checking up a level, no point trying
418
# to import things with bad names.
394
419
if re.search('\.|-| ', name):
395
420
sanitised_name = re.sub('[-. ]', '_', name)
396
421
if sanitised_name.startswith('brz_'):
573
563
version_info = getattr(self.module, 'version_info', None)
574
564
if version_info is not None:
576
if isinstance(version_info, types.StringType):
566
if isinstance(version_info, str):
577
567
version_info = version_info.split('.')
578
568
elif len(version_info) == 3:
579
569
version_info = tuple(version_info) + ('final', 0)
580
except TypeError as e:
581
571
# The given version_info isn't even iteratible
582
572
trace.log_exception_quietly()
583
573
version_info = (version_info,)
584
574
return version_info
586
def _get__version__(self):
577
def __version__(self):
587
578
version_info = self.version_info()
588
579
if version_info is None or len(version_info) == 0:
591
version_string = _format_version_tuple(version_info)
592
except (ValueError, TypeError, IndexError) as e:
582
version_string = breezy._format_version_tuple(version_info)
583
except (ValueError, TypeError, IndexError):
593
584
trace.log_exception_quietly()
594
# try to return something usefull for bad plugins, in stead of
585
# Try to show something for the version anyway
596
586
version_string = '.'.join(map(str, version_info))
597
587
return version_string
599
__version__ = property(_get__version__)
602
class _PluginImporter(object):
603
"""An importer tailored to brz specific needs.
605
This is a singleton that takes care of:
606
- disabled plugins specified in 'blacklist',
607
- plugins that needs to be loaded from specific directories.
614
self.blacklist = set()
615
self.specific_paths = {}
617
def find_module(self, fullname, parent_path=None):
618
"""Search a plugin module.
620
Disabled plugins raise an import error, plugins with specific paths
621
returns a specific loader.
623
:return: None if the plugin doesn't need special handling, self
626
if not fullname.startswith('breezy.plugins.'):
628
if fullname in self.blacklist:
629
raise ImportError('%s is disabled' % fullname)
630
if fullname in self.specific_paths:
590
class _PluginsAtFinder(object):
591
"""Meta path finder to support BRZ_PLUGINS_AT configuration."""
593
def __init__(self, prefix, names_and_paths):
595
self.names_to_path = dict((prefix + n, p) for n, p in names_and_paths)
598
return "<%s %r>" % (self.__class__.__name__, self.prefix)
600
def find_spec(self, fullname, paths, target=None):
601
"""New module spec returning find method."""
602
if fullname not in self.names_to_path:
604
path = self.names_to_path[fullname]
605
if os.path.isdir(path):
606
path = _get_package_init(path)
608
# GZ 2017-06-02: Any reason to block loading of the name from
609
# further down the path like this?
610
raise ImportError("Not loading namespace package %s as %s" % (
612
return importlib_util.spec_from_file_location(fullname, path)
614
def find_module(self, fullname, path):
615
"""Old PEP 302 import hook find_module method."""
616
if fullname not in self.names_to_path:
618
return _LegacyLoader(self.names_to_path[fullname])
621
class _LegacyLoader(object):
622
"""Source loader implementation for Python versions without importlib."""
624
def __init__(self, filepath):
625
self.filepath = filepath
628
return "<%s %r>" % (self.__class__.__name__, self.filepath)
634
630
def load_module(self, fullname):
635
631
"""Load a plugin from a specific directory (or file)."""
636
# We are called only for specific paths
637
plugin_path = self.specific_paths[fullname]
632
plugin_path = self.filepath
638
633
loading_path = None
639
634
if os.path.isdir(plugin_path):
640
for suffix, mode, kind in imp.get_suffixes():
641
if kind not in (imp.PY_SOURCE, imp.PY_COMPILED):
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# We don't recognize compiled modules (.so, .dll, etc)
644
init_path = osutils.pathjoin(plugin_path, '__init__' + suffix)
645
if os.path.isfile(init_path):
646
# We've got a module here and load_module needs specific
648
loading_path = plugin_path
651
kind = imp.PKG_DIRECTORY
635
init_path = _get_package_init(plugin_path)
636
if init_path is not None:
637
loading_path = plugin_path
640
kind = imp.PKG_DIRECTORY
654
642
for suffix, mode, kind in imp.get_suffixes():
655
643
if plugin_path.endswith(suffix):