Differential D3435 Diff 16202 swh/loader/mercurial/loader.py

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swh/loader/mercurial/loader.py

This file was copied to swh/loader/mercurial/from_bundle.py.

	# Copyright (C) 2017-2020 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

	"""This document contains a SWH loader for ingesting repository data
	from Mercurial version 2 bundle files.

	"""

	# NOTE: The code here does expensive work twice in places because of the
	# intermediate need to check for what is missing before sending to the database
	# and the desire to not juggle very large amounts of data.

	# TODO: Decide whether to also serialize to disk and read back more quickly
	# from there. Maybe only for very large repos and fast drives.
	# - Avi


	import datetime
	import os			import os
				marmouteUnsubmitted Done Inline Actions What are these two comments about ? marmoute: What are these two comments about ?
				acezarAuthorUnsubmitted Done Inline Actions This the way to switch between the two loaders. acezar: This the way to switch between the two loaders.
	from queue import Empty
	import random
	import re
	from shutil import rmtree
	from tempfile import mkdtemp
	import time
	from typing import Any, Dict, Iterable, List, Optional

	import billiard
	from dateutil import parser
	import hglib

	from swh.core.config import merge_configs
	from swh.loader.core.loader import DVCSLoader
	from swh.loader.core.utils import clean_dangling_folders
	from swh.model import identifiers
	from swh.model.hashutil import (
	DEFAULT_ALGORITHMS,
	MultiHash,
	hash_to_bytehex,
	hash_to_bytes,
	hash_to_hex,
	)
	from swh.model.model import (
	BaseContent,
	Content,
	Directory,
	ObjectType,
	Origin,
	Person,
	Release,
	Revision,
	RevisionType,
	Sha1Git,
	SkippedContent,
	Snapshot,
	SnapshotBranch,
	TargetType,
	TimestampWithTimezone,
	)
	from swh.storage.algos.origin import origin_get_latest_visit_status

	from . import converters
	from .archive_extract import tmp_extract
	from .bundle20_reader import Bundle20Reader
	from .converters import PRIMARY_ALGO as ALGO
	from .objects import SelectiveCache, SimpleTree

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

	TEMPORARY_DIR_PREFIX_PATTERN = "swh.loader.mercurial."

	HEAD_POINTER_NAME = b"tip"


	class CloneTimeoutError(Exception):
	pass


	DEFAULT_CONFIG: Dict[str, Any] = {
	"bundle_filename": "HG20_none_bundle",
	"reduce_effort": False,
	"temp_directory": "/tmp",
	"cache1_size": 800 * 1024 * 1024,
	"cache2_size": 800 * 1024 * 1024,
	"clone_timeout_seconds": 7200,
	}


	class HgBundle20Loader(DVCSLoader):
	"""Mercurial loader able to deal with remote or local repository.

	"""

	visit_type = "hg"

	def __init__(
	self,
	url,
	visit_date=None,
	directory=None,
	logging_class="swh.loader.mercurial.Bundle20Loader",
	):
	super().__init__(logging_class=logging_class)
	self.config = merge_configs(DEFAULT_CONFIG, self.config)
	self.origin_url = url
	self.visit_date = visit_date
	self.directory = directory
	self.bundle_filename = self.config["bundle_filename"]
	self.reduce_effort_flag = self.config["reduce_effort"]
	self.empty_repository = None
	self.temp_directory = self.config["temp_directory"]
	self.cache1_size = self.config["cache1_size"]
	self.cache2_size = self.config["cache2_size"]
	self.clone_timeout = self.config["clone_timeout_seconds"]
	self.working_directory = None
	self.bundle_path = None
	self.heads = {}
	self.releases = {}
	self.last_snapshot_id: Optional[bytes] = None

	def pre_cleanup(self):
	"""Cleanup potential dangling files from prior runs (e.g. OOM killed
	tasks)

	"""
	clean_dangling_folders(
	self.temp_directory,
	pattern_check=TEMPORARY_DIR_PREFIX_PATTERN,
	log=self.log,
	)

	def cleanup(self):
	"""Clean temporary working directory

	"""
	if self.bundle_path and os.path.exists(self.bundle_path):
	self.log.debug("Cleanup up working bundle %s" % self.bundle_path)
	os.unlink(self.bundle_path)
	if self.working_directory and os.path.exists(self.working_directory):
	self.log.debug(
	"Cleanup up working directory %s" % (self.working_directory,)
	)
	rmtree(self.working_directory)

	def get_heads(self, repo):
	"""Read the closed branches heads (branch, bookmarks) and returns a
	dict with key the branch_name (bytes) and values the tuple
	(pointer nature (bytes), mercurial's node id
	(bytes)). Those needs conversion to swh-ids. This is taken
	care of in get_revisions.

	"""
	b = {}
	for _, node_hash_id, pointer_nature, branch_name, *_ in repo.heads():
	b[branch_name] = (pointer_nature, hash_to_bytes(node_hash_id.decode()))

	bookmarks = repo.bookmarks()			if os.environ.get("SWH_LOADER_MERCURIAL_LOADER") == "from_disk":
	if bookmarks and bookmarks[0]:			from .from_disk import HgArchiveLoaderFromDisk as HgArchiveLoader
	for bookmark_name, _, target_short in bookmarks[0]:			from .from_disk import HgLoaderFromDisk as HgLoader
	target = repo[target_short].node()
	b[bookmark_name] = (None, hash_to_bytes(target.decode()))

	return b

	def prepare_origin_visit(self, args, *kwargs) -> None:
	self.origin = Origin(url=self.origin_url)
	visit_date = self.visit_date
	if isinstance(visit_date, str): # visit_date can be string or datetime
	visit_date = parser.parse(visit_date)
	self.visit_date = visit_date
	visit_and_status = origin_get_latest_visit_status(
	self.storage, self.origin_url, require_snapshot=True
	)
	if visit_and_status is None:
	self.last_snapshot_id = None
	else:
	_, visit_status = visit_and_status
	self.last_snapshot_id = visit_status.snapshot

	@staticmethod
	def clone_with_timeout(log, origin, destination, timeout):
	queue = billiard.Queue()
	start = time.monotonic()

	def do_clone(queue, origin, destination):
	try:
	result = hglib.clone(source=origin, dest=destination)
	except BaseException as e:
	queue.put(e)
	else:
	queue.put(result)

	process = billiard.Process(target=do_clone, args=(queue, origin, destination))
	process.start()

	while True:
	try:
	result = queue.get(timeout=0.1)
	break
	except Empty:
	duration = time.monotonic() - start
	if timeout and duration > timeout:
	log.warning(
	"Timeout cloning `%s` within %s seconds", origin, timeout
	)
	process.terminate()
	process.join()
	raise CloneTimeoutError(origin, timeout)
	continue

	process.join()
	if isinstance(result, Exception):
	raise result from None

	return result

	def prepare(self, args, *kwargs):
	"""Prepare the necessary steps to load an actual remote or local
	repository.

	To load a local repository, pass the optional directory
	parameter as filled with a path to a real local folder.

	To load a remote repository, pass the optional directory
	parameter as None.

	Args:
	origin_url (str): Origin url to load
	visit_date (str/datetime): Date of the visit
	directory (str/None): The local directory to load

	"""
	self.branches = {}
	self.tags = []
	self.releases = {}
	self.node_2_rev = {}
	self.heads = {}

	directory = self.directory

	if not directory: # remote repository
	self.working_directory = mkdtemp(
	prefix=TEMPORARY_DIR_PREFIX_PATTERN,
	suffix="-%s" % os.getpid(),
	dir=self.temp_directory,
	)
	os.makedirs(self.working_directory, exist_ok=True)
	self.hgdir = self.working_directory

	self.log.debug(
	"Cloning %s to %s with timeout %s seconds",
	self.origin_url,
	self.hgdir,
	self.clone_timeout,
	)

	self.clone_with_timeout(
	self.log, self.origin_url, self.hgdir, self.clone_timeout
	)

	else: # local repository
	self.working_directory = None
	self.hgdir = directory

	self.bundle_path = os.path.join(self.hgdir, self.bundle_filename)
	self.log.debug("Bundling at %s" % self.bundle_path)
	with hglib.open(self.hgdir) as repo:
	self.heads = self.get_heads(repo)
	repo.bundle(bytes(self.bundle_path, "utf-8"), all=True, type=b"none-v2")

	self.cache_filename1 = os.path.join(
	self.hgdir, "swh-cache-1-%s" % (hex(random.randint(0, 0xFFFFFF))[2:],)
	)
	self.cache_filename2 = os.path.join(
	self.hgdir, "swh-cache-2-%s" % (hex(random.randint(0, 0xFFFFFF))[2:],)
	)

	try:
	self.br = Bundle20Reader(
	bundlefile=self.bundle_path,
	cache_filename=self.cache_filename1,
	cache_size=self.cache1_size,
	)
	except FileNotFoundError:
	# Empty repository! Still a successful visit targeting an
	# empty snapshot
	self.log.warn("%s is an empty repository!" % self.hgdir)
	self.empty_repository = True
	else:			else:
	self.reduce_effort = set()			from .from_bundle import HgArchiveBundle20Loader as HgArchiveLoader # type: ignore
	if self.reduce_effort_flag:			from .from_bundle import HgBundle20Loader as HgLoader # type: ignore
	now = datetime.datetime.now(tz=datetime.timezone.utc)
	if (now - self.visit_date).days > 1:
	# Assuming that self.visit_date would be today for
	# a new visit, treat older visit dates as
	# indication of wanting to skip some processing
	# effort.
	for header, commit in self.br.yield_all_changesets():
	ts = commit["time"].timestamp()
	if ts < self.visit_date.timestamp():
	self.reduce_effort.add(header["node"])

	def has_contents(self):
	return not self.empty_repository

	def has_directories(self):
	return not self.empty_repository

	def has_revisions(self):
	return not self.empty_repository

	def has_releases(self):
	return not self.empty_repository

	def fetch_data(self):
	"""Fetch the data from the data source."""
	pass

	def get_contents(self) -> Iterable[BaseContent]:
	"""Get the contents that need to be loaded."""

	# NOTE: This method generates blobs twice to reduce memory usage
	# without generating disk writes.
	self.file_node_to_hash = {}
	hash_to_info = {}
	self.num_contents = 0
	contents: Dict[bytes, BaseContent] = {}
	missing_contents = set()

	for blob, node_info in self.br.yield_all_blobs():
	self.num_contents += 1
	file_name = node_info[0]
	header = node_info[2]

	length = len(blob)
	if header["linknode"] in self.reduce_effort:
	algorithms = set([ALGO])
	else:
	algorithms = DEFAULT_ALGORITHMS
	h = MultiHash.from_data(blob, hash_names=algorithms)
	content = h.digest()
	content["length"] = length
	blob_hash = content[ALGO]
	self.file_node_to_hash[header["node"]] = blob_hash

	if header["linknode"] in self.reduce_effort:
	continue

	hash_to_info[blob_hash] = node_info
	if self.max_content_size is not None and length >= self.max_content_size:
	contents[blob_hash] = SkippedContent(
	status="absent", reason="Content too large", **content
	)
	else:
	contents[blob_hash] = Content(data=blob, status="visible", **content)

	if file_name == b".hgtags":
	# https://www.mercurial-scm.org/wiki/GitConcepts#Tag_model
	# overwrite until the last one
	self.tags = (t for t in blob.split(b"\n") if t != b"")

	if contents:
	missing_contents = set(
	self.storage.content_missing(
	[c.to_dict() for c in contents.values()], key_hash=ALGO
	)
	)

	# Clusters needed blobs by file offset and then only fetches the
	# groups at the needed offsets.
	focs: Dict[int, Dict[bytes, bytes]] = {} # "file/offset/contents"
	for blob_hash in missing_contents:
	_, file_offset, header = hash_to_info[blob_hash]
	focs.setdefault(file_offset, {})
	focs[file_offset][header["node"]] = blob_hash

	for offset, node_hashes in sorted(focs.items()):
	for header, data, *_ in self.br.yield_group_objects(group_offset=offset):
	node = header["node"]
	if node in node_hashes:
	blob, meta = self.br.extract_meta_from_blob(data)
	content = contents.pop(node_hashes[node], None)
	if content:
	if (
	self.max_content_size is not None
	and len(blob) >= self.max_content_size
	):
	yield SkippedContent.from_data(
	blob, reason="Content too large"
	)
	else:
	yield Content.from_data(blob)

	def load_directories(self):
	"""This is where the work is done to convert manifest deltas from the
	repository bundle into SWH directories.

	"""
	self.mnode_to_tree_id = {}
	cache_hints = self.br.build_manifest_hints()

	def tree_size(t):
	return t.size()

	self.trees = SelectiveCache(
	cache_hints=cache_hints,
	size_function=tree_size,
	filename=self.cache_filename2,
	max_size=self.cache2_size,
	)

	tree = SimpleTree()
	for header, added, removed in self.br.yield_all_manifest_deltas(cache_hints):
	node = header["node"]
	basenode = header["basenode"]
	tree = self.trees.fetch(basenode) or tree # working tree

	for path in removed.keys():
	tree = tree.remove_tree_node_for_path(path)
	for path, info in added.items():
	file_node, is_symlink, perms_code = info
	tree = tree.add_blob(
	path, self.file_node_to_hash[file_node], is_symlink, perms_code
	)

	if header["linknode"] in self.reduce_effort:
	self.trees.store(node, tree)
	else:
	new_dirs = []
	self.mnode_to_tree_id[node] = tree.hash_changed(new_dirs)
	self.trees.store(node, tree)
	yield header, tree, new_dirs

	def get_directories(self) -> Iterable[Directory]:
	"""Compute directories to load

	"""
	dirs: Dict[Sha1Git, Directory] = {}
	self.num_directories = 0
	for _, _, new_dirs in self.load_directories():
	for d in new_dirs:
	self.num_directories += 1
	dirs[d["id"]] = Directory.from_dict(d)

	missing_dirs: List[Sha1Git] = list(dirs.keys())
	if missing_dirs:
	missing_dirs = list(self.storage.directory_missing(missing_dirs))

	for _id in missing_dirs:
	yield dirs[_id]

	def get_revisions(self) -> Iterable[Revision]:
	"""Compute revisions to load

	"""
	revisions = {}
	self.num_revisions = 0
	for header, commit in self.br.yield_all_changesets():
	if header["node"] in self.reduce_effort:
	continue

	self.num_revisions += 1
	date_dict = identifiers.normalize_timestamp(int(commit["time"].timestamp()))
	author_dict = converters.parse_author(commit["user"])
	if commit["manifest"] == Bundle20Reader.NAUGHT_NODE:
	directory_id = SimpleTree().hash_changed()
	else:
	directory_id = self.mnode_to_tree_id[commit["manifest"]]

	extra_headers = [
	(
	b"time_offset_seconds",
	str(commit["time_offset_seconds"]).encode("utf-8"),
	)
	]
	extra = commit.get("extra")
	if extra:
	for e in extra.split(b"\x00"):
	k, v = e.split(b":", 1)
	# transplant_source stores binary reference to a changeset
	# prefer to dump hexadecimal one in the revision metadata
	if k == b"transplant_source":
	v = hash_to_bytehex(v)
	extra_headers.append((k, v))

	parents = []
	p1 = self.node_2_rev.get(header["p1"])
	p2 = self.node_2_rev.get(header["p2"])
	if p1:
	parents.append(p1)
	if p2:
	parents.append(p2)

	revision = Revision(
	author=Person.from_dict(author_dict),
	date=TimestampWithTimezone.from_dict(date_dict),
	committer=Person.from_dict(author_dict),
	committer_date=TimestampWithTimezone.from_dict(date_dict),
	type=RevisionType.MERCURIAL,
	directory=directory_id,
	message=commit["message"],
	metadata={"node": hash_to_hex(header["node"]),},
	extra_headers=tuple(extra_headers),
	synthetic=False,
	parents=tuple(parents),
	)

	self.node_2_rev[header["node"]] = revision.id
	revisions[revision.id] = revision

	# Converts heads to use swh ids
	self.heads = {
	branch_name: (pointer_nature, self.node_2_rev[node_id])
	for branch_name, (pointer_nature, node_id) in self.heads.items()
	}

	missing_revs = set(revisions.keys())
	if missing_revs:
	missing_revs = set(self.storage.revision_missing(list(missing_revs)))

	for rev in missing_revs:
	yield revisions[rev]
	self.mnode_to_tree_id = None

	def _read_tag(self, tag, split_byte=b" "):
	node, *name = tag.split(split_byte)
	name = split_byte.join(name)
	return node, name

	def get_releases(self) -> Iterable[Release]:
	"""Get the releases that need to be loaded."""
	self.num_releases = 0
	releases = {}
	missing_releases = set()
	for t in self.tags:
	self.num_releases += 1
	node, name = self._read_tag(t)
	node = node.decode()
	node_bytes = hash_to_bytes(node)
	if not TAG_PATTERN.match(node):
	self.log.warn("Wrong pattern (%s) found in tags. Skipping" % (node,))
	continue
	if node_bytes not in self.node_2_rev:
	self.log.warn(
	"No matching revision for tag %s "
	"(hg changeset: %s). Skipping" % (name.decode(), node)
	)
	continue
	tgt_rev = self.node_2_rev[node_bytes]
	release = Release(
	name=name,
	target=tgt_rev,
	target_type=ObjectType.REVISION,
	message=None,
	metadata=None,
	synthetic=False,
	author=Person(name=None, email=None, fullname=b""),
	date=None,
	)
	missing_releases.add(release.id)
	releases[release.id] = release
	self.releases[name] = release.id

	if missing_releases:
	missing_releases = set(self.storage.release_missing(list(missing_releases)))

	for _id in missing_releases:
	yield releases[_id]

	def get_snapshot(self) -> Snapshot:
	"""Get the snapshot that need to be loaded."""
	branches: Dict[bytes, Optional[SnapshotBranch]] = {}
	for name, (pointer_nature, target) in self.heads.items():
	branches[name] = SnapshotBranch(
	target=target, target_type=TargetType.REVISION
	)
	if pointer_nature == HEAD_POINTER_NAME:
	branches[b"HEAD"] = SnapshotBranch(
	target=name, target_type=TargetType.ALIAS
	)
	for name, target in self.releases.items():
	branches[name] = SnapshotBranch(
	target=target, target_type=TargetType.RELEASE
	)

	self.snapshot = Snapshot(branches=branches)
	return self.snapshot

	def get_fetch_history_result(self):
	"""Return the data to store in fetch_history."""
	return {
	"contents": self.num_contents,
	"directories": self.num_directories,
	"revisions": self.num_revisions,
	"releases": self.num_releases,
	}

	def load_status(self):
	snapshot = self.get_snapshot()
	load_status = "eventful"
	if self.last_snapshot_id is not None and self.last_snapshot_id == snapshot.id:
	load_status = "uneventful"
	return {
	"status": load_status,
	}


	class HgArchiveBundle20Loader(HgBundle20Loader):
	"""Mercurial loader for repository wrapped within archives.

	"""

	def __init__(self, url, visit_date=None, archive_path=None):
	super().__init__(
	url,
	visit_date=visit_date,
	logging_class="swh.loader.mercurial.HgArchiveBundle20Loader",
	)
	self.temp_dir = None
	self.archive_path = archive_path

	def prepare(self, args, *kwargs):
	self.temp_dir = tmp_extract(
	archive=self.archive_path,
	dir=self.temp_directory,
	prefix=TEMPORARY_DIR_PREFIX_PATTERN,
	suffix=".dump-%s" % os.getpid(),
	log=self.log,
	source=self.origin_url,
	)

	repo_name = os.listdir(self.temp_dir)[0]
	self.directory = os.path.join(self.temp_dir, repo_name)
	super().prepare(args, *kwargs)

	def cleanup(self):			__all__ = ["HgArchiveLoader", "HgLoader"]
	if self.temp_dir and os.path.exists(self.temp_dir):
	rmtree(self.temp_dir)
	super().cleanup()