def pull()

in src/buildstream/_artifactcache.py [0:0]

• 50 lines of code
• 14 McCabe index (conditional complexity)

    def pull(self, element, key, *, pull_buildtrees=False):
        artifact_digest = None
        display_key = key[: self.context.log_key_length]
        project = element._get_project()

        artifact_name = element.get_artifact_name(key=key)
        uri = REMOTE_ASSET_ARTIFACT_URN_TEMPLATE.format(artifact_name)

        index_remotes, storage_remotes = self.get_remotes(project.name, False)

        errors = []
        # Start by pulling our artifact proto, so that we know which
        # blobs to pull
        for remote in index_remotes:
            remote.init()
            try:
                element.status("Pulling artifact {} <- {}".format(display_key, remote))
                response = remote.fetch_blob([uri])
                if response:
                    artifact_digest = response.blob_digest
                    break

                element.info("Remote ({}) does not have artifact {} cached".format(remote, display_key))
            except AssetCacheError as e:
                element.warn("Could not pull from remote {}: {}".format(remote, e))
                errors.append(e)

        if errors and not artifact_digest:
            raise ArtifactError(
                "Failed to pull artifact {}".format(display_key),
                detail="\n".join(str(e) for e in errors),
                temporary=True,
            )

        # If we don't have an artifact, we can't exactly pull our
        # artifact
        if not artifact_digest:
            return False

        errors = []
        # If we do, we can pull it!
        for remote in storage_remotes:
            remote.init()
            try:
                element.status("Pulling data for artifact {} <- {}".format(display_key, remote))

                if self._pull_artifact_storage(element, key, artifact_digest, remote, pull_buildtrees=pull_buildtrees):
                    element.info("Pulled artifact {} <- {}".format(display_key, remote))
                    return True

                element.info("Remote ({}) does not have artifact {} cached".format(remote, display_key))
            except BlobNotFound as e:
                # Not all blobs are available on this remote
                element.info("Remote cas ({}) does not have blob {} cached".format(remote, e.blob))
                continue
            except CASError as e:
                element.warn("Could not pull from remote {}: {}".format(remote, e))
                errors.append(e)

        if errors:
            raise ArtifactError(
                "Failed to pull artifact {}".format(display_key),
                detail="\n".join(str(e) for e in errors),
                temporary=True,
            )

        return False