| # |
| # Copyright (C) 2016 Codethink Limited |
| # |
| # This program is free software; you can redistribute it and/or |
| # modify it under the terms of the GNU Lesser General Public |
| # License as published by the Free Software Foundation; either |
| # version 2 of the License, or (at your option) any later version. |
| # |
| # This library is distributed in the hope that it will be useful, |
| # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| # Lesser General Public License for more details. |
| # |
| # You should have received a copy of the GNU Lesser General Public |
| # License along with this library. If not, see <http://www.gnu.org/licenses/>. |
| # |
| # Authors: |
| # Tristan Van Berkom <tristan.vanberkom@codethink.co.uk> |
| |
| import os |
| import inspect |
| from typing import Tuple, Type |
| |
| from .. import utils |
| from ..plugin import Plugin |
| from ..node import ProvenanceInformation |
| from ..utils import UtilError |
| from .._exceptions import PluginError |
| from .._messenger import Messenger |
| from .._message import Message, MessageType |
| |
| from .pluginorigin import PluginOrigin, PluginOriginType |
| |
| |
| # A Context for loading plugin types |
| # |
| # Args: |
| # plugin_base (PluginBase): The main PluginBase object to work with |
| # base_type (type): A base object type for this context |
| # site_plugin_path (str): Path to where buildstream keeps plugins |
| # entrypoint_group (str): Name of the entry point group that provides plugins |
| # |
| # Since multiple pipelines can be processed recursively |
| # within the same interpretor, it's important that we have |
| # one context associated to the processing of a given pipeline, |
| # this way sources and element types which are particular to |
| # a given BuildStream project are isolated to their respective |
| # Pipelines. |
| # |
| class PluginFactory: |
| def __init__(self, plugin_base, base_type, site_plugin_path, entrypoint_group): |
| |
| # The plugin kinds which were loaded |
| self.loaded_dependencies = [] |
| |
| # |
| # Private members |
| # |
| |
| # For pickling across processes, make sure this context has a unique |
| # identifier, which we prepend to the identifier of each PluginSource. |
| # This keeps plugins loaded during the first and second pass distinct |
| # from eachother. |
| self._identifier = str(id(self)) |
| |
| self._base_type = base_type # The base class plugins derive from |
| self._types = {} # Plugin type lookup table by kind |
| self._origins = {} # PluginOrigin lookup table by kind |
| self._allow_deprecated = {} # Lookup table to check if a plugin is allowed to be deprecated |
| |
| # The PluginSource object |
| self._plugin_base = plugin_base |
| self._site_plugin_path = site_plugin_path |
| self._entrypoint_group = entrypoint_group |
| self._alternate_sources = {} |
| |
| self._init_site_source() |
| |
| def _init_site_source(self): |
| self._site_source = self._plugin_base.make_plugin_source( |
| searchpath=self._site_plugin_path, identifier=self._identifier + "site", |
| ) |
| |
| def __getstate__(self): |
| state = self.__dict__.copy() |
| |
| # PluginSource is not a picklable type, so we must reconstruct this one |
| # as best we can when unpickling. |
| # |
| # Since the values of `_types` depend on the PluginSource, we must also |
| # get rid of those. It is only a cache - we will automatically recreate |
| # them on demand. |
| # |
| # Similarly we must clear out the `_alternate_sources` cache. |
| # |
| # Note that this method of referring to members is error-prone in that |
| # a later 'search and replace' renaming might miss these. Guard against |
| # this by making sure we are not creating new members, only clearing |
| # existing ones. |
| # |
| del state["_site_source"] |
| assert "_types" in state |
| state["_types"] = {} |
| assert "_alternate_sources" in state |
| state["_alternate_sources"] = {} |
| |
| return state |
| |
| def __setstate__(self, state): |
| self.__dict__.update(state) |
| |
| # Note that in order to enable plugins to be unpickled along with this |
| # PluginSource, we would also have to set and restore the 'identifier' |
| # of the PluginSource. We would also have to recreate `_types` as it |
| # was before unpickling them. We are not using this method in |
| # BuildStream, so the identifier is not restored here. |
| self._init_site_source() |
| |
| # lookup(): |
| # |
| # Fetches a type loaded from a plugin in this plugin context |
| # |
| # Args: |
| # messenger (Messenger): The messenger |
| # kind (str): The kind of Plugin to create |
| # provenance (ProvenanceInformation): The provenance from where |
| # the plugin was referenced |
| # |
| # Returns: |
| # (type): The type associated with the given kind |
| # (str): A path to the YAML file holding the plugin's defaults, or None |
| # |
| # Raises: PluginError |
| # |
| def lookup(self, messenger: Messenger, kind: str, provenance: ProvenanceInformation) -> Tuple[Type[Plugin], str]: |
| plugin_type, defaults = self._ensure_plugin(kind, provenance) |
| |
| # We can be called with None for the messenger here in the |
| # case that we've been pickled through the scheduler (see jobpickler.py), |
| # |
| # In this case we know that we've already initialized and do not need |
| # to warn about deprecated plugins a second time. |
| if messenger is None: |
| return plugin_type, defaults |
| |
| # After looking up the type, issue a warning if it's deprecated |
| # |
| # We do this here because we want to issue one warning for each time the |
| # plugin is used. |
| # |
| if plugin_type.BST_PLUGIN_DEPRECATED and not self._allow_deprecated[kind]: |
| message = Message( |
| MessageType.WARN, |
| "{}: Using deprecated plugin '{}'".format(provenance, kind), |
| detail=plugin_type.BST_PLUGIN_DEPRECATION_MESSAGE, |
| ) |
| messenger.message(message) |
| |
| return plugin_type, defaults |
| |
| # register_plugin_origin(): |
| # |
| # Registers the PluginOrigin to use for the given plugin kind |
| # |
| # Args: |
| # kind (str): The kind identifier of the Plugin |
| # origin (PluginOrigin): The PluginOrigin providing the plugin |
| # allow_deprecated (bool): Whether this plugin kind is allowed to be used in a deprecated state |
| # |
| def register_plugin_origin(self, kind: str, origin: PluginOrigin, allow_deprecated: bool): |
| if kind in self._origins: |
| raise PluginError( |
| "More than one {} plugin registered as kind '{}'".format(self._base_type.__name__, kind), |
| reason="duplicate-plugin", |
| ) |
| |
| self._origins[kind] = origin |
| self._allow_deprecated[kind] = allow_deprecated |
| |
| # all_loaded_plugins(): |
| # |
| # Returns: an iterable over all the loaded plugins. |
| # |
| def all_loaded_plugins(self): |
| return self._types.values() |
| |
| def _get_local_plugin_source(self, path): |
| if ("local", path) not in self._alternate_sources: |
| # key by a tuple to avoid collision |
| source = self._plugin_base.make_plugin_source(searchpath=[path], identifier=self._identifier + path,) |
| # Ensure that sources never get garbage collected, |
| # as they'll take the plugins with them. |
| self._alternate_sources[("local", path)] = source |
| else: |
| source = self._alternate_sources[("local", path)] |
| return source |
| |
| def _get_pip_plugin_source(self, package_name, kind): |
| defaults = None |
| if ("pip", package_name) not in self._alternate_sources: |
| import pkg_resources |
| |
| origin = self._origins[kind] |
| |
| # key by a tuple to avoid collision |
| try: |
| package = pkg_resources.get_entry_info(package_name, self._entrypoint_group, kind) |
| except pkg_resources.DistributionNotFound as e: |
| raise PluginError( |
| "{}: Failed to load {} plugin '{}': {}".format( |
| origin.provenance, self._base_type.__name__, kind, e |
| ), |
| reason="package-not-found", |
| ) from e |
| except pkg_resources.VersionConflict as e: |
| raise PluginError( |
| "{}: Version conflict encountered while loading {} plugin '{}'".format( |
| origin.provenance, self._base_type.__name__, kind |
| ), |
| detail=e.report(), |
| reason="package-version-conflict", |
| ) from e |
| except pkg_resources.RequirementParseError as e: |
| raise PluginError( |
| "{}: Malformed package-name '{}' encountered: {}".format(origin.provenance, package_name, e), |
| reason="package-malformed-requirement", |
| ) from e |
| |
| if package is None: |
| raise PluginError( |
| "{}: Pip package {} does not contain a plugin named '{}'".format( |
| origin.provenance, package_name, kind |
| ), |
| reason="plugin-not-found", |
| ) |
| |
| location = package.dist.get_resource_filename( |
| pkg_resources._manager, package.module_name.replace(".", os.sep) + ".py" |
| ) |
| |
| # Also load the defaults - required since setuptools |
| # may need to extract the file. |
| try: |
| defaults = package.dist.get_resource_filename( |
| pkg_resources._manager, package.module_name.replace(".", os.sep) + ".yaml" |
| ) |
| except KeyError: |
| # The plugin didn't have an accompanying YAML file |
| defaults = None |
| |
| source = self._plugin_base.make_plugin_source( |
| searchpath=[os.path.dirname(location)], identifier=self._identifier + os.path.dirname(location), |
| ) |
| self._alternate_sources[("pip", package_name)] = source |
| |
| else: |
| source = self._alternate_sources[("pip", package_name)] |
| |
| return source, defaults |
| |
| def _ensure_plugin(self, kind: str, provenance: ProvenanceInformation) -> Tuple[Type[Plugin], str]: |
| |
| if kind not in self._types: |
| source = None |
| defaults = None |
| |
| origin = self._origins.get(kind, None) |
| if origin: |
| # Try getting the plugin source from a registered origin |
| if origin.origin_type == PluginOriginType.LOCAL: |
| source = self._get_local_plugin_source(origin.path) |
| elif origin.origin_type == PluginOriginType.PIP: |
| source, defaults = self._get_pip_plugin_source(origin.package_name, kind) |
| else: |
| assert False, "Encountered invalid plugin origin type" |
| else: |
| # Try getting it from the core plugins |
| if kind not in self._site_source.list_plugins(): |
| raise PluginError( |
| "{}: No {} type registered for kind '{}'".format(provenance, self._base_type.__name__, kind), |
| reason="plugin-not-found", |
| ) |
| |
| source = self._site_source |
| |
| self._types[kind] = self._load_plugin(source, kind, defaults) |
| self.loaded_dependencies.append(kind) |
| |
| return self._types[kind] |
| |
| def _load_plugin(self, source, kind, defaults): |
| |
| try: |
| plugin = source.load_plugin(kind) |
| |
| if not defaults: |
| plugin_file = inspect.getfile(plugin) |
| plugin_dir = os.path.dirname(plugin_file) |
| plugin_conf_name = "{}.yaml".format(kind) |
| defaults = os.path.join(plugin_dir, plugin_conf_name) |
| |
| except ImportError as e: |
| raise PluginError("Failed to load {} plugin '{}': {}".format(self._base_type.__name__, kind, e)) from e |
| |
| try: |
| plugin_type = plugin.setup() |
| except AttributeError as e: |
| raise PluginError( |
| "{} plugin '{}' did not provide a setup() function".format(self._base_type.__name__, kind), |
| reason="missing-setup-function", |
| ) from e |
| except TypeError as e: |
| raise PluginError( |
| "setup symbol in {} plugin '{}' is not a function".format(self._base_type.__name__, kind), |
| reason="setup-is-not-function", |
| ) from e |
| |
| self._assert_plugin(kind, plugin_type) |
| self._assert_min_version(kind, plugin_type) |
| |
| return (plugin_type, defaults) |
| |
| def _assert_plugin(self, kind, plugin_type): |
| if kind in self._types: |
| raise PluginError( |
| "Tried to register {} plugin for existing kind '{}' " |
| "(already registered {})".format(self._base_type.__name__, kind, self._types[kind].__name__) |
| ) |
| try: |
| if not issubclass(plugin_type, self._base_type): |
| raise PluginError( |
| "{} plugin '{}' returned type '{}', which is not a subclass of {}".format( |
| self._base_type.__name__, kind, plugin_type.__name__, self._base_type.__name__ |
| ), |
| reason="setup-returns-bad-type", |
| ) |
| except TypeError as e: |
| raise PluginError( |
| "{} plugin '{}' returned something that is not a type (expected subclass of {})".format( |
| self._base_type.__name__, kind, self._base_type.__name__ |
| ), |
| reason="setup-returns-not-type", |
| ) from e |
| |
| def _assert_min_version(self, kind, plugin_type): |
| |
| if plugin_type.BST_MIN_VERSION is None: |
| raise PluginError( |
| "{} plugin '{}' did not specify BST_MIN_VERSION".format(self._base_type.__name__, kind), |
| reason="missing-min-version", |
| detail="Are you trying to use a BuildStream 1 plugin with a BuildStream 2 project ?", |
| ) |
| |
| try: |
| min_version_major, min_version_minor = utils._parse_version(plugin_type.BST_MIN_VERSION) |
| except UtilError as e: |
| raise PluginError( |
| "{} plugin '{}' specified malformed BST_MIN_VERSION: {}".format( |
| self._base_type.__name__, kind, plugin_type.BST_MIN_VERSION |
| ), |
| reason="malformed-min-version", |
| detail="BST_MIN_VERSION must be specified as 'MAJOR.MINOR' with " |
| + "numeric major and minor minimum required version numbers", |
| ) from e |
| |
| bst_major, bst_minor = utils._get_bst_api_version() |
| |
| if min_version_major != bst_major: |
| raise PluginError( |
| "{} plugin '{}' requires BuildStream {}, but is being loaded with BuildStream {}".format( |
| self._base_type.__name__, kind, min_version_major, bst_major |
| ), |
| reason="incompatible-major-version", |
| detail="You will need to find the correct version of this plugin for your project.", |
| ) |
| |
| if min_version_minor > bst_minor: |
| raise PluginError( |
| "{} plugin '{}' requires BuildStream {}, but is being loaded with BuildStream {}.{}".format( |
| self._base_type.__name__, kind, plugin_type.BST_MIN_VERSION, bst_major, bst_minor |
| ), |
| reason="incompatible-minor-version", |
| detail="Please upgrade to BuildStream {}".format(plugin_type.BST_MIN_VERSION), |
| ) |