Source code for swh.loader.mercurial.identify

# Copyright (C) 2020-2021  The Software Heritage developers
# See the AUTHORS file at the top-level directory of this distribution
# License: GNU General Public License version 3, or any later version
# See top-level LICENSE file for more information

from codecs import escape_decode  # type: ignore
import json
from pathlib import Path
import re
import subprocess
from typing import Any, Dict, Iterator, List, NamedTuple, Optional, Union

# WARNING: do not import unnecessary things here to keep cli startup time under
# control
import click

from swh.loader.mercurial.utils import get_minimum_env
from swh.model.cli import identify_object
from swh.model.hashutil import hash_to_bytehex
from swh.model.identifiers import CoreSWHID, ObjectType, normalize_timestamp
from swh.model.model import RevisionType

TAG_PATTERN = re.compile(b"([0-9A-Fa-f]{40}) +(.+)")


[docs]class HgAuthor(NamedTuple): """Represent a Mercurial revision author.""" fullname: bytes """full name of the author""" name: Optional[bytes] """name of the author""" email: Optional[bytes] """email of the author"""
[docs] @staticmethod def from_bytes(data: bytes) -> "HgAuthor": """Convert bytes to an HgAuthor named tuple. Expected format: "name <email>" """ from swh.loader.mercurial.converters import parse_author result = parse_author(data) return HgAuthor( fullname=result["fullname"], name=result["name"], email=result["email"] )
[docs] def to_dict(self) -> Dict[str, Optional[bytes]]: return {"fullname": self.fullname, "name": self.name, "email": self.email}
HG_REVISION_TEMPLATE = "\n".join( [ "node_id:{node}", "author:{author}", "timestamp_offset:{date|json}", "p1:{p1.node}", "p2:{p2.node}", "extras:{join(extras, '\nextras:')}", ] ) # Log template for HgRevision.from_bytes NULL_NODE_ID = b"0" * 40 # Value used when no parent
[docs]class HgRevision(NamedTuple): """Represent a Mercurial revision.""" node_id: bytes """raw bytes of the revision hash""" author: HgAuthor """author of the revision""" timestamp: bytes """timestamp of the revision""" offset: bytes """offset of the revision""" parents: List[bytes] """hex bytes of the revision's parents""" extras: Dict[bytes, bytes] """metadata of the revision""" description: bytes """description of the revision"""
[docs] @staticmethod def from_bytes(data: bytes, description: bytes) -> "HgRevision": """Convert bytes to an HgRevision named tuple. Expected data format: ''' node_id:{node} author:{author} timestamp_offset:[{timestamp}, {offset}] p1:{p1} p2:{p2} extras:{key1}={value1} ... extras:{keyn}={value} ''' """ lines = data.split(b"\n") tuples = [line.split(b":", 1) for line in lines] fields: Dict[str, Any] = { "parents": [], "extras": {}, "description": description, } for key, value in tuples: if key == b"timestamp_offset": timestamp, offset = json.loads(value) fields["timestamp"] = timestamp fields["offset"] = offset elif key in (b"p1", b"p2"): if value != NULL_NODE_ID: fields["parents"].append(value) elif key == b"extras": extra_key, extra_value = value.split(b"=", 1) fields["extras"][extra_key] = extra_value elif key == b"author": fields["author"] = HgAuthor.from_bytes(value) else: fields[key.decode()] = value return HgRevision(**fields)
[docs] def branch(self) -> bytes: return self.extras.get(b"branch", b"default")
[docs] def to_dict(self) -> Dict: """Convert a HgRevision to a dict for SWHID computation""" date = normalize_timestamp(int(self.timestamp)) extra_headers = [ (b"time_offset_seconds", str(self.offset).encode("utf-8")), ] for key, value in self.extras.items(): if key == b"branch" and value == b"default": # branch default is skipped to match historical implementation continue if key == b"transplant_source": # transplant_source is converted to hex # to match historical implementation value = hash_to_bytehex(escape_decode(value)[0]) extra_headers.append((key, value)) author = self.author.to_dict() return { "author": author, "date": date, "committer": author, "committer_date": date, "type": RevisionType.MERCURIAL.value, "message": self.description, "metadata": {"node": self.node_id}, "extra_headers": tuple(extra_headers), "synthetic": False, "parents": self.parents, }
[docs]class HgBranch(NamedTuple): """Represent a Mercurial branch.""" name: bytes """name of the branch""" node_id: bytes """row bytes of the target revision hash"""
[docs]class HgTag(NamedTuple): """Represent a Mercurial tag.""" name: bytes """name of the tag""" node_id: bytes """hex bytes of the target revision"""
[docs]class Hg: """Provide methods to extract data from a Mercurial repository.""" def __init__(self, repository_root: Path) -> None: self._root = repository_root def _output(self, *args) -> bytes: """Return the outpout of a `hg` call.""" return subprocess.check_output( ["hg", *args], cwd=self._root, env=get_minimum_env() ) def _call(self, *args) -> None: """Perform a `hg` call.""" subprocess.check_call( ["hg", *args], cwd=self._root, stderr=subprocess.PIPE, stdout=subprocess.PIPE, env=get_minimum_env(), )
[docs] def root(self) -> Path: """Return the root of the Mercurial repository.""" return self._root
[docs] def log(self, rev: Optional[Union[bytes, str]] = None) -> List[HgRevision]: """Return the specified revisions of the Mercurial repository. Mercurial revsets are supported. (See `hg help revsets`) If no revision range is specified, return all revisions". """ if rev: node_ids = self._output("log", "-r", rev, "-T", "{node}\n").splitlines() else: node_ids = self._output("log", "-T", "{node}\n").splitlines() revisions = [self._revision(node_id) for node_id in reversed(node_ids)] return revisions
def _revision(self, revision: bytes) -> HgRevision: data = self._output("log", "-r", revision, "-T", HG_REVISION_TEMPLATE) # hg log strips the description so the raw description has to be taken # from debugdata # The description follows some metadata and is separated from them # by an empty line _, desc = self._output("debugdata", "-c", revision).split(b"\n\n", 1) return HgRevision.from_bytes(data, desc)
[docs] def up(self, rev: bytes) -> None: """Update the repository working directory to the specified revision.""" self._call("up", rev)
[docs] def branches(self) -> List[HgBranch]: """List the repository named branches.""" output = self._output("branches", "-T", "{branch}\n{node}\n\n").strip() branches = [] for block in output.split(b"\n\n"): name, node_id = block.splitlines() branches.append(HgBranch(name=name, node_id=node_id)) return branches
[docs] def tip(self) -> HgRevision: """Return the `tip` node-id.""" return self.log("tip")[0]
[docs] def tags(self) -> List[HgTag]: """Return the repository's tags as defined in the `.hgtags` file. `.hgtags` being like any other repository's tracked file, its content can vary from revision to revision. The returned value therefore depends on the current revision of the repository. """ hgtags = self._root / ".hgtags" tags = {} if hgtags.is_file(): for line in hgtags.read_bytes().splitlines(): match = TAG_PATTERN.match(line) if match is None: continue node_id, name = match.groups() tags[node_id] = name return [HgTag(name=name, node_id=node_id) for node_id, name in tags.items()]
@click.group() @click.option( "--directory", "-d", help=("Path to the Mercurial repository. If unset, the current directory is used"), ) @click.pass_context def main(ctx, directory=None): """Compute the Software Heritage persistent identifier (SWHID) for the given source code object(s). For more details about SWHIDs see: https://docs.softwareheritage.org/devel/swh-model/persistent-identifiers.html """ # ensure that ctx.obj exists and is a dict (in case `cli()` is called # by means other than the `if` block below) ctx.ensure_object(dict) root = Path(directory) if directory else Path() if not root.exists(): raise IOError(f"{root!r} does not exists") ctx.obj["HG_ROOT"] = root
[docs]def identify_directory(path: Path) -> CoreSWHID: """Return the SWHID of the given path.""" return CoreSWHID.from_string( identify_object( "directory", follow_symlinks=True, exclude_patterns=[b".hg"], obj=str(path) ) )
[docs]class RevisionIdentity(NamedTuple): """Represent a swh revision identity.""" swhid: CoreSWHID """SWH Identifier of the revision.""" node_id: bytes """node_id hex bytes""" directory_swhid: CoreSWHID """SWH Identifier of the directory"""
[docs] def dir_uri(self) -> str: """Return the SWHID uri of the revision's directory.""" return f"{self.directory_swhid}\t{self.node_id.decode()}"
def __str__(self) -> str: """Return the string representation of a RevisionIdentity.""" return f"{self.swhid}\t{self.node_id.decode()}"
[docs]def identify_revision( hg: Hg, rev: Optional[bytes] = None, node_id_2_swhid: Optional[Dict[bytes, CoreSWHID]] = None, ) -> Iterator[RevisionIdentity]: """Return the repository revision identities. Args: hg: A `Hg` repository instance rev: An optional revision or Mercurial revsets (See `hg help revsets`) If not provided all the repository revisions will be computed. node_id_2_swhid: An optional cache mapping hg node ids to SWHIDs It will be updated in place with new mappings. """ from swh.model.model import Revision if node_id_2_swhid is None: node_id_2_swhid = {} for revision in hg.log(rev): data = revision.to_dict() hg.up(revision.node_id) directory_swhid = identify_directory(hg.root()) data["directory"] = directory_swhid.object_id parents = [] for parent in data["parents"]: if parent not in node_id_2_swhid: parent_revision = next(identify_revision(hg, parent, node_id_2_swhid)) node_id_2_swhid[parent] = parent_revision.swhid assert node_id_2_swhid[parent].object_type == ObjectType.REVISION parents.append(node_id_2_swhid[parent].object_id) data["parents"] = parents revision_swhid = Revision.from_dict(data).swhid() node_id_2_swhid[revision.node_id] = revision_swhid yield RevisionIdentity( swhid=revision_swhid, node_id=revision.node_id, directory_swhid=directory_swhid, )
[docs]class ReleaseIdentity(NamedTuple): """Represent a swh release identity.""" swhid: CoreSWHID """SWH Identifier of the release.""" node_id: bytes """node_id hex bytes""" name: bytes """name of the release""" def __str__(self) -> str: """Return the string representation of a ReleaseIdentity.""" return f"{self.swhid}\t{self.name.decode()}"
[docs]def identify_release( hg: Hg, node_id_2_swhid: Optional[Dict[bytes, CoreSWHID]] = None, ) -> Iterator[ReleaseIdentity]: """Return the repository's release identities. Args: hg: A `Hg` repository instance node_id_2_swhid: An optional cache mapping hg node ids to SWHIDs If not provided it will be computed using `identify_revision`. """ from swh.model.model import ObjectType as ModelObjectType from swh.model.model import Release if node_id_2_swhid is None: node_id_2_swhid = { revision.node_id: revision.swhid for revision in identify_revision(hg) } for tag in hg.tags(): assert node_id_2_swhid[tag.node_id].object_type == ObjectType.REVISION data = { "name": tag.name, "target": node_id_2_swhid[tag.node_id].object_id, "target_type": ModelObjectType.REVISION.value, "message": None, "metadata": None, "synthetic": False, "author": {"name": None, "email": None, "fullname": b""}, "date": None, } release_swhid = Release.from_dict(data).swhid() yield ReleaseIdentity( swhid=release_swhid, node_id=tag.node_id, name=tag.name, )
[docs]def identify_snapshot( hg: Hg, node_id_2_swhid: Optional[Dict[bytes, CoreSWHID]] = None, releases: Optional[List[ReleaseIdentity]] = None, ) -> CoreSWHID: """Return the repository snapshot identity. Args: hg: A `Hg` repository instance node_id_2_swhid: An optional cache mapping hg node ids to SWHIDs If not provided it will be computed using `identify_revision`. release: an optional list of `ReleaseIdentity`. If not provided it will be computed using `identify_release`. """ from swh.model.model import Snapshot, TargetType if node_id_2_swhid is None: node_id_2_swhid = { revision.node_id: revision.swhid for revision in identify_revision(hg) } if releases is None: releases = [release for release in identify_release(hg, node_id_2_swhid)] branches = {} tip = hg.tip() branches[b"HEAD"] = { "target": tip.branch(), "target_type": TargetType.ALIAS.value, } for branch in hg.branches(): assert node_id_2_swhid[branch.node_id].object_type == ObjectType.REVISION branches[branch.name] = { "target": node_id_2_swhid[branch.node_id].object_id, "target_type": TargetType.REVISION.value, } for release in releases: assert release.swhid.object_type == ObjectType.RELEASE branches[release.name] = { "target": release.swhid.object_id, "target_type": TargetType.RELEASE.value, } return Snapshot.from_dict({"branches": branches}).swhid()
@main.command() @click.argument("rev", required=False) @click.pass_context def revision(ctx, rev): """Compute the SWHID of a given revision. If specified REV allow to select a single or multiple revisions (using the Mercurial revsets language: `hg help revsets`) """ hg = Hg(ctx.obj["HG_ROOT"]) for identity in identify_revision(hg, rev): click.echo(identity) @main.command() @click.pass_context def snapshot(ctx): """Compute the SWHID of the snapshot.""" root = ctx.obj["HG_ROOT"] hg = Hg(root) snapshot_swhid = identify_snapshot(hg) click.echo(f"{snapshot_swhid}\t{root}") @main.command() @click.pass_context def all(ctx): """Compute the SWHID of all the repository objects.""" root = ctx.obj["HG_ROOT"] hg = Hg(root) dir_uris = [] rev_uris = [] rel_uris = [] node_id_2_swhid = {} for revision in identify_revision(hg): dir_uris.append(revision.dir_uri()) rev_uris.append(str(revision)) node_id_2_swhid[revision.node_id] = revision.swhid releases = [] for release in identify_release(hg, node_id_2_swhid): rel_uris.append(str(release)) releases.append(release) snapshot_swhid = identify_snapshot(hg, node_id_2_swhid, releases) for uri in dir_uris + rev_uris + rel_uris: click.echo(uri) click.echo(f"{snapshot_swhid}\t{root}") if __name__ == "__main__": main()