def _add_found_extension(self, obj, ext):
"""
:obj: Found extension class
:ext: matching extension item.
"""
self.logger.debug('\tAdding %s %s', ext.name, obj.name)
key = identifier(obj.name.lower())
obj.kind = ext.name
if key in self.extensions or key in self.aliases:
raise LoaderError('{} {} already exists.'.format(
ext.name, obj.name))
# Extensions are tracked both, in a common extensions
# dict, and in per-extension kind dict (as retrieving
# extensions by kind is a common use case.
self.extensions[key] = obj
store = self._get_store(ext)
store[key] = obj
for alias in obj.aliases:
alias_id = identifier(alias.name)
if alias_id in self.extensions or alias_id in self.aliases:
raise LoaderError('{} {} already exists.'.format(
ext.name, obj.name))
self.aliases[alias_id] = alias
# Update global aliases list. If a global alias is already in the list,
# then make sure this extension is in the same parent/child hierarchy
# as the one already found.
for param in obj.parameters:
if param.global_alias:
if param.global_alias not in self.global_param_aliases:
ga = GlobalParameterAlias(param.global_alias)
ga.update(obj)
self.global_param_aliases[ga.name] = ga
else: # global alias already exists.
self.global_param_aliases[param.global_alias].update(obj)
def _load_from_paths(self, paths, ignore_paths):
self.logger.debug('Loading from paths.')
for path in paths:
self.logger.debug('Checking path %s', path)
for root, _, files in os.walk(path):
should_skip = False
for igpath in ignore_paths:
if root.startswith(igpath):
should_skip = True
break
if should_skip:
continue
for fname in files:
if not os.path.splitext(fname)[1].lower() == '.py':
continue
filepath = os.path.join(root, fname)
try:
modname = os.path.splitext(
filepath[1:])[0].translate(MODNAME_TRANS)
module = imp.load_source(modname, filepath)
self._load_module(module)
except (SystemExit, ImportError), e:
if self.keep_going:
self.logger.warn(
'Failed to load {}'.format(filepath))
self.logger.warn('Got: {}'.format(e))
else:
raise LoaderError(
'Failed to load {}'.format(filepath),
sys.exc_info())
except Exception as e:
message = 'Problem loading extensions from {}: {}'
raise LoaderError(message.format(filepath, e))
def _validate_ext(self, other_ext):
other_param = self.get_param(other_ext)
for param, ext in self.iteritems():
if ((not (issubclass(ext, other_ext) or issubclass(other_ext, ext))) and
other_param.kind != param.kind):
message = 'Duplicate global alias {} declared in {} and {} extensions with different types'
raise LoaderError(message.format(self.name, ext.name, other_ext.name))
if not param.name == other_param.name:
message = 'Two params {} in {} and {} in {} both declare global alias {}'
raise LoaderError(message.format(param.name, ext.name,
other_param.name, other_ext.name, self.name))
def _instantiate(cls, args=None, kwargs=None):
args = [] if args is None else args
kwargs = {} if kwargs is None else kwargs
try:
return cls(*args, **kwargs)
except Exception:
raise LoaderError('Could not load {}'.format(cls), sys.exc_info())
def _load_from_packages(self, packages):
try:
for package in packages:
for module in walk_modules(package):
self._load_module(module)
except ImportError as e:
message = 'Problem loading extensions from package {}: {}'
raise LoaderError(message.format(package, e.message))
def _load_module(self, module): # NOQA pylint: disable=too-many-branches
self.logger.debug('Checking module %s', module.__name__)
for obj in vars(module).itervalues():
if inspect.isclass(obj):
if not issubclass(obj, Extension) or not hasattr(obj, 'name') or not obj.name:
continue
try:
for ext in self.extension_kinds.values():
if issubclass(obj, ext.cls):
self._add_found_extension(obj, ext)
break
else: # did not find a matching Extension type
message = 'Unknown extension type for {} (type: {})'
raise LoaderError(message.format(obj.name, obj.__class__.__name__))
except LoaderError as e:
if self.keep_going:
self.logger.warning(e)
else:
raise e