diff options
| -rw-r--r-- | src/buildstream/_loader/loadcontext.py | 48 | ||||
| -rw-r--r-- | src/buildstream/_loader/loader.py | 119 | ||||
| -rw-r--r-- | src/buildstream/_project.py | 7 | ||||
| -rw-r--r-- | src/buildstream/exceptions.py | 3 | ||||
| -rw-r--r-- | src/buildstream/plugins/elements/junction.py | 23 |
5 files changed, 156 insertions, 44 deletions
diff --git a/src/buildstream/_loader/loadcontext.py b/src/buildstream/_loader/loadcontext.py index 161be913b..65b7e9157 100644 --- a/src/buildstream/_loader/loadcontext.py +++ b/src/buildstream/_loader/loadcontext.py @@ -17,6 +17,9 @@ # Authors: # Tristan Van Berkom <tristan.vanberkom@codethink.co.uk> +from .._exceptions import LoadError +from ..exceptions import LoadErrorReason + # LoaderContext() # @@ -34,6 +37,9 @@ class LoadContext: self.fetch_subprojects = None self.task = None + # A table of all Loaders, indexed by project name + self._loaders = {} + # set_rewritable() # # Sets whether the projects are to be loaded in a rewritable fashion, @@ -64,3 +70,45 @@ class LoadContext: # def set_fetch_subprojects(self, fetch_subprojects): self.fetch_subprojects = fetch_subprojects + + # register_loader() + # + # Registers a new loader in the load context, possibly + # raising an error in the case of a conflict + # + # Args: + # loader (Loader): The Loader object to register into context + # + # Raises: + # (LoadError): A CONFLICTING_JUNCTION LoadError in the case of a conflict + # + def register_loader(self, loader): + project = loader.project + existing_loader = self._loaders.get(project.name, None) + + if existing_loader: + + assert project.junction is not None + + if existing_loader.project.junction: + # The existing provenance can be None even if there is a junction, this + # can happen when specifying a full element path on the command line. + # + provenance_str = "" + if existing_loader.provenance: + provenance_str = ": {}".format(existing_loader.provenance) + + detail = "Project '{}' was already loaded by junction '{}'{}".format( + project.name, existing_loader.project.junction._get_full_name(), provenance_str + ) + else: + detail = "Project '{}' is also the toplevel project".format(project.name) + + raise LoadError( + "{}: Error loading project '{}' from junction: {}".format( + loader.provenance, project.name, project.junction._get_full_name() + ), + LoadErrorReason.CONFLICTING_JUNCTION, + detail=detail, + ) + self._loaders[project.name] = loader diff --git a/src/buildstream/_loader/loader.py b/src/buildstream/_loader/loader.py index e63dd6c57..76d5eef82 100644 --- a/src/buildstream/_loader/loader.py +++ b/src/buildstream/_loader/loader.py @@ -46,9 +46,10 @@ from .._message import Message, MessageType # Args: # project (Project): The toplevel Project object # parent (Loader): A parent Loader object, in the case this is a junctioned Loader +# provenance (ProvenanceInformation): The provenance of the reference to this project's junction # class Loader: - def __init__(self, project, *, parent=None): + def __init__(self, project, *, parent=None, provenance=None): # Ensure we have an absolute path for the base directory basedir = project.element_path @@ -60,6 +61,7 @@ class Loader: # self.load_context = project.load_context # The LoadContext self.project = project # The associated Project + self.provenance = provenance # The provenance of whence this loader was instantiated self.loaded = None # The number of loaded Elements # @@ -73,9 +75,14 @@ class Loader: self._meta_elements = {} # Dict of resolved meta elements by name self._elements = {} # Dict of elements self._loaders = {} # Dict of junction loaders + self._loader_search_provenances = {} # Dictionary of provenances of ongoing child loader searches self._includes = Includes(self, copy_tree=True) + assert project.name is not None + + self.load_context.register_loader(self) + # load(): # # Loads the project based on the parameters given to the constructor @@ -163,12 +170,27 @@ class Loader: # Returns: # (Loader): loader for sub-project # - def get_loader(self, name, provenance, *, level=0): + def get_loader(self, name, provenance): junction_path = name.split(":") loader = self + circular_provenance = self._loader_search_provenances.get(name, None) + if circular_provenance: + detail = None + if circular_provenance is not provenance: + detail = "Already searching for '{}' at: {}".format(name, circular_provenance) + raise LoadError( + "{}: Circular reference while searching for '{}'".format(provenance, name), + LoadErrorReason.CIRCULAR_REFERENCE, + detail=detail, + ) + + self._loader_search_provenances[name] = provenance + for junction_name in junction_path: - loader = loader._get_loader(junction_name, provenance, level=level) + loader = loader._get_loader(junction_name, provenance) + + del self._loader_search_provenances[name] return loader @@ -514,6 +536,40 @@ class Loader: return self._meta_elements[top_element.name] + # _search_for_override(): + # + # Search parent projects for an overridden subproject to replace this junction. + # + # Args: + # filename (str): Junction name + # + def _search_for_override(self, filename): + loader = self + override_path = filename + + # Collect any overrides to this junction in the ancestry + # + overriding_loaders = [] + while loader._parent: + junction = loader.project.junction + override_filename, override_provenance = junction.overrides.get(override_path, (None, None)) + if override_filename: + overriding_loaders.append((loader, override_filename, override_provenance)) + + override_path = junction.name + ":" + override_path + loader = loader._parent + + # If there are any overriding loaders, use the highest one in + # the ancestry to lookup the loader for this project. + # + if overriding_loaders: + loader, filename, provenance = overriding_loaders[-1] + return loader._parent.get_loader(filename, provenance) + + # No overrides were found in the ancestry + # + return None + # _get_loader(): # # Return loader for specified junction @@ -526,7 +582,7 @@ class Loader: # # Returns: A Loader or None if specified junction does not exist # - def _get_loader(self, filename, provenance, *, level=0): + def _get_loader(self, filename, provenance): loader = None provenance_str = "" if provenance is not None: @@ -534,43 +590,21 @@ class Loader: # return previously determined result if filename in self._loaders: - loader = self._loaders[filename] - - if loader is None: - # do not allow junctions with the same name in different - # subprojects - raise LoadError( - "{}Conflicting junction {} in subprojects, define junction in {}".format( - provenance_str, filename, self.project.name - ), - LoadErrorReason.CONFLICTING_JUNCTION, - ) - - return loader + return self._loaders[filename] - if self._parent: - # junctions in the parent take precedence over junctions defined - # in subprojects - loader = self._parent._get_loader(filename, level=level + 1, provenance=provenance) - if loader: - self._loaders[filename] = loader - return loader - - try: - self._load_file(filename, provenance=provenance) - except LoadError as e: - if e.reason != LoadErrorReason.MISSING_FILE: - # other load error - raise - - if level == 0: - # junction element not found in this or ancestor projects - raise + # + # Search the ancestry for an overridden loader to use in place + # of using the locally defined junction. + # + override_loader = self._search_for_override(filename) + if override_loader: + self._loaders[filename] = override_loader + return override_loader - # mark junction as not available to allow detection of - # conflicting junctions in subprojects - self._loaders[filename] = None - return None + # + # Load the junction file + # + self._load_file(filename, provenance) # At this point we've loaded the LoadElement load_element = self._elements[filename] @@ -668,7 +702,12 @@ class Loader: from .._project import Project # pylint: disable=cyclic-import project = Project( - project_dir, self.load_context.context, junction=element, parent_loader=self, search_for_project=False, + project_dir, + self.load_context.context, + junction=element, + parent_loader=self, + search_for_project=False, + provenance=provenance, ) except LoadError as e: if e.reason == LoadErrorReason.MISSING_PROJECT_CONF: diff --git a/src/buildstream/_project.py b/src/buildstream/_project.py index e0ddf3d41..fcfb31988 100644 --- a/src/buildstream/_project.py +++ b/src/buildstream/_project.py @@ -99,6 +99,7 @@ class Project: cli_options=None, default_mirror=None, parent_loader=None, + provenance=None, search_for_project=True, ): @@ -164,7 +165,7 @@ class Project: self._project_includes = None with PROFILER.profile(Topics.LOAD_PROJECT, self.directory.replace(os.sep, "-")): - self._load(parent_loader=parent_loader) + self._load(parent_loader=parent_loader, provenance=provenance) self._partially_loaded = True @@ -653,7 +654,7 @@ class Project: # # Raises: LoadError if there was a problem with the project.conf # - def _load(self, *, parent_loader=None): + def _load(self, *, parent_loader=None, provenance=None): # Load builtin default projectfile = os.path.join(self.directory, _PROJECT_CONF_FILE) @@ -700,7 +701,7 @@ class Project: # Fatal warnings self._fatal_warnings = pre_config_node.get_str_list("fatal-warnings", default=[]) - self.loader = Loader(self, parent=parent_loader) + self.loader = Loader(self, parent=parent_loader, provenance=provenance) self._project_includes = Includes(self.loader, copy_tree=False) diff --git a/src/buildstream/exceptions.py b/src/buildstream/exceptions.py index 2c455be84..e77d64fe7 100644 --- a/src/buildstream/exceptions.py +++ b/src/buildstream/exceptions.py @@ -142,3 +142,6 @@ class LoadErrorReason(Enum): LINK_FORBIDDEN_DEPENDENCIES = 25 """A link element declared dependencies""" + + CIRCULAR_REFERENCE = 26 + """A circular element reference was detected""" diff --git a/src/buildstream/plugins/elements/junction.py b/src/buildstream/plugins/elements/junction.py index 3e221cce7..3396a04ab 100644 --- a/src/buildstream/plugins/elements/junction.py +++ b/src/buildstream/plugins/elements/junction.py @@ -161,13 +161,34 @@ class JunctionElement(Element): def configure(self, node): - node.validate_keys(["path", "options", "cache-junction-elements", "ignore-junction-remotes"]) + node.validate_keys(["path", "options", "cache-junction-elements", "ignore-junction-remotes", "overrides"]) self.path = node.get_str("path", default="") self.options = node.get_mapping("options", default={}) self.cache_junction_elements = node.get_bool("cache-junction-elements", default=False) self.ignore_junction_remotes = node.get_bool("ignore-junction-remotes", default=False) + # The overrides dictionary has the target junction + # to override as a key, and a tuple consisting + # of the local overriding junction and the provenance + # of the override declaration. + self.overrides = {} + overrides_node = node.get_mapping("overrides", {}) + for key, value in overrides_node.items(): + junction_name = value.as_str() + provenance = value.get_provenance() + + # Cannot override a subproject with the project itself + # + if junction_name == self.name: + raise ElementError( + "{}: Attempt to override subproject junction '{}' with the overriding junction '{}' itself".format( + provenance, key, junction_name + ), + reason="override-junction-with-self", + ) + self.overrides[key] = (junction_name, provenance) + def preflight(self): pass |