Limnoria/src/plugin.py

201 lines
7.9 KiB
Python

###
# Copyright (c) 2002-2005, Jeremiah Fincher
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice,
# this list of conditions, and the following disclaimer.
# * Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions, and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
# * Neither the name of the author of this software nor the name of
# contributors to this software may be used to endorse or promote products
# derived from this software without specific prior written consent.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
###
import os
import re
import sys
import os.path
import linecache
import importlib.util
try:
import pkg_resources
except ImportError:
pkg_resources = None
if not hasattr(importlib.util, 'module_from_spec'):
# Python < 3.5
import imp
from . import callbacks, conf, log, registry
ENTRYPOINT_GROUPS = [
'limnoria.plugins',
]
installDir = os.path.dirname(sys.modules[__name__].__file__)
_pluginsDir = os.path.join(installDir, 'plugins')
class Deprecated(ImportError):
pass
def loadPluginFromEntrypoint(name):
if pkg_resources:
for entrypoint_group in ENTRYPOINT_GROUPS:
for entrypoint in pkg_resources.iter_entry_points(entrypoint_group):
if entrypoint.name.lower() == name.lower():
return entrypoint.load()
return None
def loadPluginModule(name, ignoreDeprecation=False):
"""Loads (and returns) the module for the plugin with the given name."""
files = []
pluginDirs = conf.supybot.directories.plugins()[:]
pluginDirs.append(_pluginsDir)
module = None
for dir in pluginDirs:
try:
files.extend(os.listdir(dir))
except EnvironmentError: # OSError, IOError superclass.
log.warning('Invalid plugin directory: %s; removing.', dir)
conf.supybot.directories.plugins().remove(dir)
if name not in files:
search = lambda x: re.search(r'(?i)^%s$' % (name,), x)
matched_names = list(filter(search, files))
if len(matched_names) >= 1:
name = matched_names[0]
else:
module = loadPluginFromEntrypoint(name)
if module is None:
raise ImportError(name)
if module is None:
# Found by listing files; must now import it
try:
if hasattr(importlib.util, 'module_from_spec'):
# Python >= 3.5
spec = importlib.machinery.PathFinder.find_spec(name, pluginDirs)
if spec is None or spec.loader is None:
# spec is None if 'name' can't be found; and
# spec.loader might be None in some rare occasions as well
# (eg. for namespace packages)
raise ImportError(name)
module = importlib.util.module_from_spec(spec)
sys.modules[module.__name__] = module
spec.loader.exec_module(module)
else:
# Python < 3.5
moduleInfo = imp.find_module(name, pluginDirs)
module = imp.load_module(name, *moduleInfo)
except:
sys.modules.pop(name, None)
keys = list(sys.modules.keys())
for key in keys:
if key.startswith(name + '.'):
sys.modules.pop(key)
raise
if 'deprecated' in module.__dict__ and module.deprecated:
if ignoreDeprecation:
log.warning('Deprecated plugin loaded: %s', name)
else:
raise Deprecated(format('Attempted to load deprecated plugin %s',
name))
if module.__name__ in sys.modules:
sys.modules[module.__name__] = module
linecache.checkcache()
return module
def renameCommand(cb, name, newName):
assert not hasattr(cb, newName), 'Cannot rename over existing attributes.'
assert newName == callbacks.canonicalName(newName), \
'newName must already be normalized.'
if name != newName:
method = getattr(cb.__class__, name)
setattr(cb.__class__, newName, method)
delattr(cb.__class__, name)
def registerRename(plugin, command=None, newName=None):
g = conf.registerGlobalValue(conf.supybot.commands.renames, plugin,
registry.SpaceSeparatedSetOfStrings([], """Determines what commands
in this plugin are to be renamed."""))
if command is not None:
g().add(command)
v = conf.registerGlobalValue(g, command, registry.String('', ''))
if newName is not None:
v.setValue(newName) # In case it was already registered.
return v
else:
return g
def loadPluginClass(irc, module, register=None):
"""Loads the plugin Class from the given module into the given Irc."""
try:
cb = module.Class(irc)
except TypeError as e:
s = str(e)
if '2 given' in s and '__init__' in s:
raise callbacks.Error('In our switch from CVS to Darcs (after 0.80.1), we ' \
'changed the __init__ for callbacks.Privmsg* to also ' \
'accept an irc argument. This plugin (%s) is overriding ' \
'its __init__ method and needs to update its prototype ' \
'to be \'def __init__(self, irc):\' as well as passing ' \
'that irc object on to any calls to the plugin\'s ' \
'parent\'s __init__. Another possible cause: the code in ' \
'your __init__ raised a TypeError when calling a function ' \
'or creating an object, which doesn\'t take 2 arguments.' %\
module.__name__)
else:
raise
except AttributeError as e:
if 'Class' in str(e):
raise callbacks.Error('This plugin module doesn\'t have a "Class" ' \
'attribute to specify which plugin should be ' \
'instantiated. If you didn\'t write this ' \
'plugin, but received it with Supybot, file ' \
'a bug with us about this error.')
else:
raise
cb.classModule = module
plugin = cb.name()
public = True
if hasattr(cb, 'public'):
public = cb.public
conf.registerPlugin(plugin, register, public)
assert not irc.getCallback(plugin), \
'There is already a %r plugin registered.' % plugin
try:
v = registerRename(plugin)
renames = conf.supybot.commands.renames.get(plugin)()
if renames:
for command in renames:
v = registerRename(plugin, command)
newName = v()
assert newName
renameCommand(cb, command, newName)
else:
conf.supybot.commands.renames.unregister(plugin)
except registry.NonExistentRegistryEntry as e:
pass # The plugin isn't there.
irc.addCallback(cb)
return cb
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