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
18
"""bzr python plugin support.
20
When load_plugins() is invoked, any python module in any directory in
21
$BZR_PLUGIN_PATH will be imported. The module will be imported as
22
'bzrlib.plugins.$BASENAME(PLUGIN)'. In the plugin's main body, it should
23
update any bzrlib 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.
25
33
See the plugin-api developer documentation for information about writing
28
BZR_PLUGIN_PATH is also honoured for any plugins imported via
29
'import bzrlib.plugins.PLUGINNAME', as long as set_plugins_path has been
36
from bzrlib import osutils
38
from bzrlib.lazy_import import lazy_import
44
from .lazy_import import lazy_import
40
45
lazy_import(globals(), """
47
from importlib import util as importlib_util
46
_format_version_tuple,
52
from bzrlib import plugins as _mod_plugins
55
from bzrlib.symbol_versioning import (
61
DEFAULT_PLUGIN_PATH = None
63
_plugins_disabled = False
66
def are_plugins_disabled():
67
return _plugins_disabled
70
def disable_plugins():
62
_MODULE_PREFIX = "breezy.plugins."
67
def disable_plugins(state=None):
71
68
"""Disable loading plugins.
73
70
Future calls to load_plugins() will be ignored.
72
:param state: The library state object that records loaded plugins.
75
global _plugins_disabled
76
_plugins_disabled = True
80
def _strip_trailing_sep(path):
81
return path.rstrip("\\/")
84
def set_plugins_path(path=None):
85
"""Set the path for plugins to be loaded from.
75
state = breezy.get_global_state()
79
def load_plugins(path=None, state=None):
80
"""Load breezy plugins.
82
The environment variable BRZ_PLUGIN_PATH is considered a delimited
83
set of paths to look through. Each entry is searched for `*.py`
84
files (and whatever other extensions are used in the platform,
87
87
:param path: The list of paths to search for plugins. By default,
88
path will be determined using get_standard_plugins_path.
89
if path is [], no plugins can be loaded.
88
it is populated from the __path__ of the breezy.plugins package.
89
:param state: The library state object that records loaded plugins.
92
state = breezy.get_global_state()
93
if getattr(state, 'plugins', None) is not None:
94
# People can make sure plugins are loaded, they just won't be twice
92
path = get_standard_plugins_path()
93
_mod_plugins.__path__ = path
94
PluginImporter.reset()
95
# Set up a blacklist for disabled plugins
96
disabled_plugins = os.environ.get('BZR_DISABLE_PLUGINS', None)
97
if disabled_plugins is not None:
98
for name in disabled_plugins.split(os.pathsep):
99
PluginImporter.blacklist.add('bzrlib.plugins.' + name)
100
# Set up a the specific paths for plugins
101
specific_plugins = os.environ.get('BZR_PLUGINS_AT', None)
102
if specific_plugins is not None:
103
for spec in specific_plugins.split(os.pathsep):
104
plugin_name, plugin_path = spec.split('@')
105
PluginImporter.specific_paths[
106
'bzrlib.plugins.%s' % plugin_name] = plugin_path
110
def _append_new_path(paths, new_path):
111
"""Append a new path if it set and not already known."""
112
if new_path is not None and new_path not in paths:
113
paths.append(new_path)
117
def get_core_plugin_path():
119
bzr_exe = bool(getattr(sys, 'frozen', None))
120
if bzr_exe: # expand path for bzr.exe
98
# Calls back into extend_path() here
99
from breezy.plugins import __path__ as path
101
state.plugin_warnings = {}
102
_load_plugins_from_path(state, path)
103
if (None, 'entrypoints') in _env_plugin_path():
104
_load_plugins_from_entrypoints(state)
105
state.plugins = plugins()
108
def _load_plugins_from_entrypoints(state):
112
# No pkg_resources, no entrypoints.
115
for ep in pkg_resources.iter_entry_points('breezy.plugin'):
116
fullname = _MODULE_PREFIX + ep.name
117
if fullname in sys.modules:
119
sys.modules[fullname] = ep.load()
122
def plugin_name(module_name):
123
"""Gives unprefixed name from module_name or None."""
124
if module_name.startswith(_MODULE_PREFIX):
125
parts = module_name.split(".")
131
def extend_path(path, name):
132
"""Helper so breezy.plugins can be a sort of namespace package.
134
To be used in similar fashion to pkgutil.extend_path:
136
from breezy.plugins import extend_path
137
__path__ = extend_path(__path__, __name__)
139
Inspects the BRZ_PLUGIN* envvars, sys.path, and the filesystem to find
140
plugins. May mutate sys.modules in order to block plugin loading, and may
141
append a new meta path finder to sys.meta_path for plugins@ loading.
143
Returns a list of paths to import from, as an enhanced object that also
144
contains details of the other configuration used.
146
blocks = _env_disable_plugins()
147
_block_plugins(blocks)
149
extra_details = _env_plugins_at()
150
_install_importer_if_needed(extra_details)
152
paths = _iter_plugin_paths(_env_plugin_path(), path)
154
return _Path(name, blocks, extra_details, paths)
158
"""List type to use as __path__ but containing additional details.
160
Python 3 allows any iterable for __path__ but Python 2 is more fussy.
163
def __init__(self, package_name, blocked, extra, paths):
164
super(_Path, self).__init__(paths)
165
self.package_name = package_name
166
self.blocked_names = blocked
167
self.extra_details = extra
170
return "%s(%r, %r, %r, %s)" % (
171
self.__class__.__name__, self.package_name, self.blocked_names,
172
self.extra_details, list.__repr__(self))
175
def _expect_identifier(name, env_key, env_value):
176
"""Validate given name from envvar is usable as a Python identifier.
178
Returns the name as a native str, or None if it was invalid.
180
Per PEP 3131 this is no longer strictly correct for Python 3, but as MvL
181
didn't include a neat way to check except eval, this enforces ascii.
183
if re.match(r"^[A-Za-z_][A-Za-z0-9_]*$", name) is None:
184
trace.warning("Invalid name '%s' in %s='%s'", name, env_key, env_value)
189
def _env_disable_plugins(key='BRZ_DISABLE_PLUGINS'):
190
"""Gives list of names for plugins to disable from environ key."""
192
env = osutils.path_from_environ(key)
194
for name in env.split(os.pathsep):
195
name = _expect_identifier(name, key, env)
197
disabled_names.append(name)
198
return disabled_names
201
def _env_plugins_at(key='BRZ_PLUGINS_AT'):
202
"""Gives list of names and paths of specific plugins from environ key."""
204
env = osutils.path_from_environ(key)
206
for pair in env.split(os.pathsep):
208
name, path = pair.split('@', 1)
211
name = osutils.basename(path).split('.', 1)[0]
212
name = _expect_identifier(name, key, env)
214
plugin_details.append((name, path))
215
return plugin_details
218
def _env_plugin_path(key='BRZ_PLUGIN_PATH'):
219
"""Gives list of paths and contexts for plugins from environ key.
221
Each entry is either a specific path to load plugins from and the value
222
'path', or None and one of the values 'user', 'core', 'entrypoints', 'site'.
225
env = osutils.path_from_environ(key)
230
'entrypoints': False,
233
# Add paths specified by user in order
234
for p in env.split(os.pathsep):
235
flag, name = p[:1], p[1:]
236
if flag in ("+", "-") and name in defaults:
237
if flag == "+" and defaults[name] is not None:
238
path_details.append((None, name))
239
defaults[name] = None
241
path_details.append((p, 'path'))
243
# Add any remaining default paths
244
for name in ('user', 'core', 'entrypoints', 'site'):
246
path_details.append((None, name))
251
def _iter_plugin_paths(paths_from_env, core_paths):
252
"""Generate paths using paths_from_env and core_paths."""
253
# GZ 2017-06-02: This is kinda horrid, should make better.
254
for path, context in paths_from_env:
255
if context == 'path':
257
elif context == 'user':
258
path = get_user_plugin_path()
259
if os.path.isdir(path):
261
elif context == 'core':
262
for path in _get_core_plugin_paths(core_paths):
264
elif context == 'site':
265
for path in _get_site_plugin_paths(sys.path):
266
if os.path.isdir(path):
270
def _install_importer_if_needed(plugin_details):
271
"""Install a meta path finder to handle plugin_details if any."""
273
finder = _PluginsAtFinder(_MODULE_PREFIX, plugin_details)
274
# For Python 3, must insert before default PathFinder to override.
275
sys.meta_path.insert(2, finder)
278
def _load_plugins_from_path(state, paths):
279
"""Do the importing all plugins from paths."""
280
imported_names = set()
281
for name, path in _iter_possible_plugins(paths):
282
if name not in imported_names:
283
msg = _load_plugin_module(name, path)
285
state.plugin_warnings.setdefault(name, []).append(msg)
286
imported_names.add(name)
289
def _block_plugins(names):
290
"""Add names to sys.modules to block future imports."""
292
package_name = _MODULE_PREFIX + name
293
if sys.modules.get(package_name) is not None:
294
trace.mutter("Blocked plugin %s already loaded.", name)
295
sys.modules[package_name] = None
298
def _get_package_init(package_path):
299
"""Get path of __init__ file from package_path or None if not a package."""
300
init_path = osutils.pathjoin(package_path, "__init__.py")
301
if os.path.exists(init_path):
303
init_path = init_path[:-3] + COMPILED_EXT
304
if os.path.exists(init_path):
309
def _iter_possible_plugins(plugin_paths):
310
"""Generate names and paths of possible plugins from plugin_paths."""
311
# Inspect any from BRZ_PLUGINS_AT first.
312
for name, path in getattr(plugin_paths, "extra_details", ()):
314
# Then walk over files and directories in the paths from the package.
315
for path in plugin_paths:
316
if os.path.isfile(path):
317
if path.endswith(".zip"):
318
trace.mutter("Don't yet support loading plugins from zip.")
320
for name, path in _walk_modules(path):
324
def _walk_modules(path):
325
"""Generate name and path of modules and packages on path."""
326
for root, dirs, files in os.walk(path):
330
if f.endswith((".py", COMPILED_EXT)):
331
yield f.rsplit(".", 1)[0], root
335
package_dir = osutils.pathjoin(root, d)
336
fullpath = _get_package_init(package_dir)
337
if fullpath is not None:
339
# Don't descend into subdirectories
343
def describe_plugins(show_paths=False, state=None):
344
"""Generate text description of plugins.
346
Includes both those that have loaded, and those that failed to load.
348
:param show_paths: If true, include the plugin path.
349
:param state: The library state object to inspect.
350
:returns: Iterator of text lines (including newlines.)
353
state = breezy.get_global_state()
354
loaded_plugins = getattr(state, 'plugins', {})
355
plugin_warnings = set(getattr(state, 'plugin_warnings', []))
356
all_names = sorted(set(loaded_plugins.keys()).union(plugin_warnings))
357
for name in all_names:
358
if name in loaded_plugins:
359
plugin = loaded_plugins[name]
360
version = plugin.__version__
361
if version == 'unknown':
363
yield '%s %s\n' % (name, version)
364
d = plugin.module.__doc__
366
doc = d.split('\n')[0]
368
doc = '(no description)'
369
yield (" %s\n" % doc)
371
yield (" %s\n" % plugin.path())
373
yield "%s (failed to load)\n" % name
374
if name in state.plugin_warnings:
375
for line in state.plugin_warnings[name]:
376
yield " ** " + line + '\n'
380
def _get_core_plugin_paths(existing_paths):
381
"""Generate possible locations for plugins based on existing_paths."""
382
if getattr(sys, 'frozen', False):
121
383
# We need to use relative path to system-wide plugin
122
# directory because bzrlib from standalone bzr.exe
384
# directory because breezy from standalone brz.exe
123
385
# could be imported by another standalone program
124
# (e.g. bzr-config; or TortoiseBzr/Olive if/when they
386
# (e.g. brz-config; or TortoiseBzr/Olive if/when they
125
387
# will become standalone exe). [bialix 20071123]
126
388
# __file__ typically is
127
# C:\Program Files\Bazaar\lib\library.zip\bzrlib\plugin.pyc
389
# C:\Program Files\Bazaar\lib\library.zip\breezy\plugin.pyc
128
390
# then plugins directory is
129
391
# C:\Program Files\Bazaar\plugins
130
392
# so relative path is ../../../plugins
131
core_path = osutils.abspath(osutils.pathjoin(
132
osutils.dirname(__file__), '../../../plugins'))
393
yield osutils.abspath(osutils.pathjoin(
394
osutils.dirname(__file__), '../../../plugins'))
133
395
else: # don't look inside library.zip
134
# search the plugin path before the bzrlib installed dir
135
core_path = os.path.dirname(_mod_plugins.__file__)
139
def get_site_plugin_path():
140
"""Returns the path for the site installed plugins."""
141
if sys.platform == 'win32':
142
# We don't have (yet) a good answer for windows since that is certainly
143
# related to the way we build the installers. -- vila20090821
147
from distutils.sysconfig import get_python_lib
149
# If distutuils is not available, we just don't know where they are
152
site_path = osutils.pathjoin(get_python_lib(), 'bzrlib', 'plugins')
396
for path in existing_paths:
400
def _get_site_plugin_paths(sys_paths):
401
"""Generate possible locations for plugins from given sys_paths."""
402
for path in sys_paths:
403
if os.path.basename(path) in ('dist-packages', 'site-packages'):
404
yield osutils.pathjoin(path, 'breezy', 'plugins')
156
407
def get_user_plugin_path():
157
return osutils.pathjoin(config.config_dir(), 'plugins')
160
def get_standard_plugins_path():
161
"""Determine a plugin path suitable for general use."""
162
# Ad-Hoc default: core is not overriden by site but user can overrides both
163
# The rationale is that:
164
# - 'site' comes last, because these plugins should always be available and
165
# are supposed to be in sync with the bzr installed on site.
166
# - 'core' comes before 'site' so that running bzr from sources or a user
167
# installed version overrides the site version.
168
# - 'user' comes first, because... user is always right.
169
# - the above rules clearly defines which plugin version will be loaded if
170
# several exist. Yet, it is sometimes desirable to disable some directory
171
# so that a set of plugins is disabled as once. This can be done via
172
# -site, -core, -user.
174
env_paths = os.environ.get('BZR_PLUGIN_PATH', '+user').split(os.pathsep)
175
defaults = ['+core', '+site']
177
# The predefined references
178
refs = dict(core=get_core_plugin_path(),
179
site=get_site_plugin_path(),
180
user=get_user_plugin_path())
182
# Unset paths that should be removed
183
for k,v in refs.iteritems():
185
# defaults can never mention removing paths as that will make it
186
# impossible for the user to revoke these removals.
187
if removed in env_paths:
188
env_paths.remove(removed)
193
for p in env_paths + defaults:
194
if p.startswith('+'):
195
# Resolve references if they are known
199
# Leave them untouched so user can still use paths starting
202
_append_new_path(paths, p)
204
# Get rid of trailing slashes, since Python can't handle them when
205
# it tries to import modules.
206
paths = map(_strip_trailing_sep, paths)
210
def load_plugins(path=None):
211
"""Load bzrlib plugins.
213
The environment variable BZR_PLUGIN_PATH is considered a delimited
214
set of paths to look through. Each entry is searched for *.py
215
files (and whatever other extensions are used in the platform,
218
load_from_path() provides the underlying mechanism and is called with
219
the default directory list to provide the normal behaviour.
221
:param path: The list of paths to search for plugins. By default,
222
path will be determined using get_standard_plugins_path.
223
if path is [], no plugins can be loaded.
227
# People can make sure plugins are loaded, they just won't be twice
231
# scan for all plugins in the path.
232
load_from_path(set_plugins_path(path))
235
def load_from_path(dirs):
236
"""Load bzrlib plugins found in each dir in dirs.
238
Loading a plugin means importing it into the python interpreter.
239
The plugin is expected to make calls to register commands when
240
it's loaded (or perhaps access other hooks in future.)
242
Plugins are loaded into bzrlib.plugins.NAME, and can be found there
243
for future reference.
245
The python module path for bzrlib.plugins will be modified to be 'dirs'.
247
# Explicitly load the plugins with a specific path
248
for fullname, path in PluginImporter.specific_paths.iteritems():
249
name = fullname[len('bzrlib.plugins.'):]
250
_load_plugin_module(name, path)
252
# We need to strip the trailing separators here as well as in the
253
# set_plugins_path function because calling code can pass anything in to
254
# this function, and since it sets plugins.__path__, it should set it to
255
# something that will be valid for Python to use (in case people try to
256
# run "import bzrlib.plugins.PLUGINNAME" after calling this function).
257
_mod_plugins.__path__ = map(_strip_trailing_sep, dirs)
261
trace.mutter('looking for plugins in %s', d)
266
# backwards compatability: load_from_dirs was the old name
267
# This was changed in 0.15
268
load_from_dirs = load_from_path
271
def _find_plugin_module(dir, name):
272
"""Check if there is a valid python module that can be loaded as a plugin.
274
:param dir: The directory where the search is performed.
275
:param path: An existing file path, either a python file or a package
278
:return: (name, path, description) name is the module name, path is the
279
file to load and description is the tuple returned by
282
path = osutils.pathjoin(dir, name)
283
if os.path.isdir(path):
284
# Check for a valid __init__.py file, valid suffixes depends on -O and
285
# can be .py, .pyc and .pyo
286
for suffix, mode, kind in imp.get_suffixes():
287
if kind not in (imp.PY_SOURCE, imp.PY_COMPILED):
288
# We don't recognize compiled modules (.so, .dll, etc)
290
init_path = osutils.pathjoin(path, '__init__' + suffix)
291
if os.path.isfile(init_path):
292
return name, init_path, (suffix, mode, kind)
294
for suffix, mode, kind in imp.get_suffixes():
295
if name.endswith(suffix):
296
# Clean up the module name
297
name = name[:-len(suffix)]
298
if kind == imp.C_EXTENSION and name.endswith('module'):
299
name = name[:-len('module')]
300
return name, path, (suffix, mode, kind)
301
# There is no python module here
302
return None, None, (None, None, None)
408
return osutils.pathjoin(bedding.config_dir(), 'plugins')
411
def record_plugin_warning(warning_message):
412
trace.mutter(warning_message)
413
return warning_message
305
416
def _load_plugin_module(name, dir):
306
"""Load plugin name from dir.
417
"""Load plugin by name.
308
:param name: The plugin name in the bzrlib.plugins namespace.
419
:param name: The plugin name in the breezy.plugins namespace.
309
420
:param dir: The directory the plugin is loaded from for error messages.
311
if ('bzrlib.plugins.%s' % name) in PluginImporter.blacklist:
422
if _MODULE_PREFIX + name in sys.modules:
314
exec "import bzrlib.plugins.%s" % name in {}
315
except KeyboardInterrupt:
317
except errors.IncompatibleAPI, e:
318
trace.warning("Unable to load plugin %r. It requested API version "
319
"%s of module %s but the minimum exported version is %s, and "
320
"the maximum is %s" %
321
(name, e.wanted, e.api, e.minimum, e.current))
323
trace.warning("%s" % e)
324
if re.search('\.|-| ', name):
325
sanitised_name = re.sub('[-. ]', '_', name)
326
if sanitised_name.startswith('bzr_'):
327
sanitised_name = sanitised_name[len('bzr_'):]
328
trace.warning("Unable to load %r in %r as a plugin because the "
329
"file path isn't a valid module name; try renaming "
330
"it to %r." % (name, dir, sanitised_name))
332
trace.warning('Unable to load plugin %r from %r' % (name, dir))
425
__import__(_MODULE_PREFIX + name)
426
except errors.IncompatibleVersion as e:
428
"Unable to load plugin %r. It supports %s "
429
"versions %r but the current version is %s" %
430
(name, e.api.__name__, e.wanted, e.current))
431
return record_plugin_warning(warning_message)
432
except Exception as e:
333
433
trace.log_exception_quietly()
334
434
if 'error' in debug.debug_flags:
335
435
trace.print_exception(sys.exc_info(), sys.stderr)
338
def load_from_dir(d):
339
"""Load the plugins in directory d.
341
d must be in the plugins module path already.
342
This function is called once for each directory in the module path.
345
for p in os.listdir(d):
346
name, path, desc = _find_plugin_module(d, p)
348
if name == '__init__':
349
# We do nothing with the __init__.py file in directories from
350
# the bzrlib.plugins module path, we may want to, one day
352
continue # We don't load __init__.py in the plugins dirs
353
elif getattr(_mod_plugins, name, None) is not None:
354
# The module has already been loaded from another directory
355
# during a previous call.
356
# FIXME: There should be a better way to report masked plugins
358
trace.mutter('Plugin name %s already loaded', name)
360
plugin_names.add(name)
362
for name in plugin_names:
363
_load_plugin_module(name, d)
436
# GZ 2017-06-02: Move this name checking up a level, no point trying
437
# to import things with bad names.
438
if re.search('\\.|-| ', name):
439
sanitised_name = re.sub('[-. ]', '_', name)
440
if sanitised_name.startswith('brz_'):
441
sanitised_name = sanitised_name[len('brz_'):]
442
trace.warning("Unable to load %r in %r as a plugin because the "
443
"file path isn't a valid module name; try renaming "
444
"it to %r." % (name, dir, sanitised_name))
446
return record_plugin_warning(
447
'Unable to load plugin %r from %r: %s' % (name, dir, e))
added
removed
breezy/plugin.py
