diff --git a/swh/model/model.py b/swh/model/model.py index f6e8a5b..5cc40af 100644 --- a/swh/model/model.py +++ b/swh/model/model.py @@ -1,734 +1,733 @@ # Copyright (C) 2018-2019 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 import datetime from abc import ABCMeta, abstractmethod from enum import Enum from typing import Dict, List, Optional, Union import attr from attrs_strict import type_validator import dateutil.parser import iso8601 from .identifiers import ( normalize_timestamp, directory_identifier, revision_identifier, release_identifier, snapshot_identifier ) from .hashutil import DEFAULT_ALGORITHMS, hash_to_bytes, MultiHash class MissingData(Exception): """Raised by `Content.with_data` when it has no way of fetching the data (but not when fetching the data fails).""" pass SHA1_SIZE = 20 # TODO: Limit this to 20 bytes Sha1Git = bytes def dictify(value): "Helper function used by BaseModel.to_dict()" if isinstance(value, BaseModel): return value.to_dict() elif isinstance(value, Enum): return value.value elif isinstance(value, dict): return {k: dictify(v) for k, v in value.items()} elif isinstance(value, list): return [dictify(v) for v in value] else: return value class BaseModel: """Base class for SWH model classes. Provides serialization/deserialization to/from Python dictionaries, that are suitable for JSON/msgpack-like formats.""" def to_dict(self): """Wrapper of `attr.asdict` that can be overridden by subclasses that have special handling of some of the fields.""" return dictify(attr.asdict(self, recurse=False)) @classmethod def from_dict(cls, d): """Takes a dictionary representing a tree of SWH objects, and recursively builds the corresponding objects.""" return cls(**d) class HashableObject(metaclass=ABCMeta): """Mixin to automatically compute object identifier hash when the associated model is instantiated.""" @staticmethod @abstractmethod def compute_hash(object_dict): """Derived model classes must implement this to compute the object hash from its dict representation.""" pass def __attrs_post_init__(self): if not self.id: obj_id = hash_to_bytes(self.compute_hash(self.to_dict())) object.__setattr__(self, 'id', obj_id) @attr.s(frozen=True) class Person(BaseModel): """Represents the author/committer of a revision or release.""" fullname = attr.ib( type=bytes, validator=type_validator()) name = attr.ib( type=Optional[bytes], validator=type_validator()) email = attr.ib( type=Optional[bytes], validator=type_validator()) @classmethod def from_fullname(cls, fullname: bytes): """Returns a Person object, by guessing the name and email from the fullname, in the `name ` format. The fullname is left unchanged.""" if fullname is None: raise TypeError('fullname is None.') name: Optional[bytes] email: Optional[bytes] try: open_bracket = fullname.index(b'<') except ValueError: name = fullname email = None else: raw_name = fullname[:open_bracket] raw_email = fullname[open_bracket+1:] if not raw_name: name = None else: name = raw_name.strip() try: close_bracket = raw_email.rindex(b'>') except ValueError: email = raw_email else: email = raw_email[:close_bracket] return Person( name=name or None, email=email or None, fullname=fullname, ) @attr.s(frozen=True) class Timestamp(BaseModel): """Represents a naive timestamp from a VCS.""" seconds = attr.ib( type=int, validator=type_validator()) microseconds = attr.ib( type=int, validator=type_validator()) @seconds.validator def check_seconds(self, attribute, value): """Check that seconds fit in a 64-bits signed integer.""" if not (-2**63 <= value < 2**63): raise ValueError('Seconds must be a signed 64-bits integer.') @microseconds.validator def check_microseconds(self, attribute, value): """Checks that microseconds are positive and < 1000000.""" if not (0 <= value < 10**6): raise ValueError('Microseconds must be in [0, 1000000[.') @attr.s(frozen=True) class TimestampWithTimezone(BaseModel): """Represents a TZ-aware timestamp from a VCS.""" timestamp = attr.ib( type=Timestamp, validator=type_validator()) offset = attr.ib( type=int, validator=type_validator()) negative_utc = attr.ib( type=bool, validator=type_validator()) @offset.validator def check_offset(self, attribute, value): """Checks the offset is a 16-bits signed integer (in theory, it should always be between -14 and +14 hours).""" if not (-2**15 <= value < 2**15): # max 14 hours offset in theory, but you never know what # you'll find in the wild... raise ValueError('offset too large: %d minutes' % value) @negative_utc.validator def check_negative_utc(self, attribute, value): if self.offset and value: raise ValueError("negative_utc can only be True is offset=0") @classmethod def from_dict(cls, obj: Union[Dict, datetime.datetime, int]): """Builds a TimestampWithTimezone from any of the formats accepted by :func:`swh.model.normalize_timestamp`.""" # TODO: this accept way more types than just dicts; find a better # name d = normalize_timestamp(obj) return cls( timestamp=Timestamp.from_dict(d['timestamp']), offset=d['offset'], negative_utc=d['negative_utc']) @classmethod def from_datetime(cls, dt: datetime.datetime): return cls.from_dict(dt) @classmethod def from_iso8601(cls, s): """Builds a TimestampWithTimezone from an ISO8601-formatted string. """ dt = iso8601.parse_date(s) tstz = cls.from_datetime(dt) if dt.tzname() == '-00:00': tstz = attr.evolve(tstz, negative_utc=True) return tstz @attr.s(frozen=True) class Origin(BaseModel): """Represents a software source: a VCS and an URL.""" url = attr.ib( type=str, validator=type_validator()) @attr.s(frozen=True) class OriginVisit(BaseModel): """Represents a visit of an origin at a given point in time, by a SWH loader.""" origin = attr.ib( type=str, validator=type_validator()) date = attr.ib( type=datetime.datetime, validator=type_validator()) status = attr.ib( type=str, validator=attr.validators.in_(['ongoing', 'full', 'partial'])) type = attr.ib( type=str, validator=type_validator()) snapshot = attr.ib( type=Optional[Sha1Git], validator=type_validator()) metadata = attr.ib( type=Optional[Dict[str, object]], validator=type_validator(), default=None) visit = attr.ib( type=Optional[int], validator=type_validator(), default=None) """Should not be set before calling 'origin_visit_add()'.""" def to_dict(self): """Serializes the date as a string and omits the visit id if it is `None`.""" ov = super().to_dict() if ov['visit'] is None: del ov['visit'] return ov @classmethod def from_dict(cls, d): """Parses the date from a string, and accepts missing visit ids.""" if isinstance(d['date'], str): d = d.copy() d['date'] = dateutil.parser.parse(d['date']) return super().from_dict(d) @attr.s(frozen=True) class OriginVisitUpdate(BaseModel): """Represents a visit update of an origin at a given point in time. """ origin = attr.ib( type=str, validator=type_validator()) visit = attr.ib( type=int, validator=type_validator()) date = attr.ib( type=datetime.datetime, validator=type_validator()) status = attr.ib( type=str, validator=attr.validators.in_(['ongoing', 'full', 'partial'])) snapshot = attr.ib( type=Optional[Sha1Git], validator=type_validator()) metadata = attr.ib( type=Optional[Dict[str, object]], validator=type_validator(), default=None) class TargetType(Enum): """The type of content pointed to by a snapshot branch. Usually a revision or an alias.""" CONTENT = 'content' DIRECTORY = 'directory' REVISION = 'revision' RELEASE = 'release' SNAPSHOT = 'snapshot' ALIAS = 'alias' class ObjectType(Enum): """The type of content pointed to by a release. Usually a revision""" CONTENT = 'content' DIRECTORY = 'directory' REVISION = 'revision' RELEASE = 'release' SNAPSHOT = 'snapshot' @attr.s(frozen=True) class SnapshotBranch(BaseModel): """Represents one of the branches of a snapshot.""" target = attr.ib( type=bytes, validator=type_validator()) target_type = attr.ib( type=TargetType, validator=type_validator()) @target.validator def check_target(self, attribute, value): """Checks the target type is not an alias, checks the target is a valid sha1_git.""" if self.target_type != TargetType.ALIAS and self.target is not None: if len(value) != 20: raise ValueError('Wrong length for bytes identifier: %d' % len(value)) @classmethod def from_dict(cls, d): return cls( target=d['target'], target_type=TargetType(d['target_type'])) @attr.s(frozen=True) class Snapshot(BaseModel, HashableObject): """Represents the full state of an origin at a given point in time.""" branches = attr.ib( type=Dict[bytes, Optional[SnapshotBranch]], validator=type_validator()) id = attr.ib( type=Sha1Git, validator=type_validator(), default=b'') @staticmethod def compute_hash(object_dict): return snapshot_identifier(object_dict) @classmethod def from_dict(cls, d): d = d.copy() return cls( branches={ name: SnapshotBranch.from_dict(branch) if branch else None for (name, branch) in d.pop('branches').items() }, **d) @attr.s(frozen=True) class Release(BaseModel, HashableObject): name = attr.ib( type=bytes, validator=type_validator()) message = attr.ib( type=bytes, validator=type_validator()) target = attr.ib( type=Optional[Sha1Git], validator=type_validator()) target_type = attr.ib( type=ObjectType, validator=type_validator()) synthetic = attr.ib( type=bool, validator=type_validator()) author = attr.ib( type=Optional[Person], validator=type_validator(), default=None) date = attr.ib( type=Optional[TimestampWithTimezone], validator=type_validator(), default=None) metadata = attr.ib( type=Optional[Dict[str, object]], validator=type_validator(), default=None) id = attr.ib( type=Sha1Git, validator=type_validator(), default=b'') @staticmethod def compute_hash(object_dict): return release_identifier(object_dict) @author.validator def check_author(self, attribute, value): """If the author is `None`, checks the date is `None` too.""" if self.author is None and self.date is not None: raise ValueError('release date must be None if author is None.') def to_dict(self): rel = super().to_dict() if rel['metadata'] is None: del rel['metadata'] return rel @classmethod def from_dict(cls, d): d = d.copy() if d.get('author'): d['author'] = Person.from_dict(d['author']) if d.get('date'): d['date'] = TimestampWithTimezone.from_dict(d['date']) return cls( target_type=ObjectType(d.pop('target_type')), **d) class RevisionType(Enum): GIT = 'git' TAR = 'tar' DSC = 'dsc' SUBVERSION = 'svn' MERCURIAL = 'hg' @attr.s(frozen=True) class Revision(BaseModel, HashableObject): message = attr.ib( type=bytes, validator=type_validator()) author = attr.ib( type=Person, validator=type_validator()) committer = attr.ib( type=Person, validator=type_validator()) date = attr.ib( type=Optional[TimestampWithTimezone], validator=type_validator()) committer_date = attr.ib( type=Optional[TimestampWithTimezone], validator=type_validator()) type = attr.ib( type=RevisionType, validator=type_validator()) directory = attr.ib( type=Sha1Git, validator=type_validator()) synthetic = attr.ib( type=bool, validator=type_validator()) metadata = attr.ib( type=Optional[Dict[str, object]], validator=type_validator(), default=None) parents = attr.ib( type=List[Sha1Git], validator=type_validator(), default=attr.Factory(list)) id = attr.ib( type=Sha1Git, validator=type_validator(), default=b'') @staticmethod def compute_hash(object_dict): return revision_identifier(object_dict) @classmethod def from_dict(cls, d): d = d.copy() date = d.pop('date') if date: date = TimestampWithTimezone.from_dict(date) committer_date = d.pop('committer_date') if committer_date: committer_date = TimestampWithTimezone.from_dict( committer_date) return cls( author=Person.from_dict(d.pop('author')), committer=Person.from_dict(d.pop('committer')), date=date, committer_date=committer_date, type=RevisionType(d.pop('type')), **d) @attr.s(frozen=True) class DirectoryEntry(BaseModel): name = attr.ib( type=bytes, validator=type_validator()) type = attr.ib( type=str, validator=attr.validators.in_(['file', 'dir', 'rev'])) target = attr.ib( type=Sha1Git, validator=type_validator()) perms = attr.ib( type=int, validator=type_validator()) """Usually one of the values of `swh.model.from_disk.DentryPerms`.""" @attr.s(frozen=True) class Directory(BaseModel, HashableObject): entries = attr.ib( type=List[DirectoryEntry], validator=type_validator()) id = attr.ib( type=Sha1Git, validator=type_validator(), default=b'') @staticmethod def compute_hash(object_dict): return directory_identifier(object_dict) @classmethod def from_dict(cls, d): d = d.copy() return cls( entries=[DirectoryEntry.from_dict(entry) for entry in d.pop('entries')], **d) @attr.s(frozen=True) class BaseContent(BaseModel): status = attr.ib( type=str, validator=attr.validators.in_(['visible', 'hidden', 'absent'])) @staticmethod def _hash_data(data: bytes): """Hash some data, returning most of the fields of a content object""" d = MultiHash.from_data(data).digest() d['data'] = data d['length'] = len(data) return d def to_dict(self): content = super().to_dict() if content['ctime'] is None: del content['ctime'] return content @classmethod def from_dict(cls, d, use_subclass=True): if use_subclass: # Chooses a subclass to instantiate instead. if d['status'] == 'absent': return SkippedContent.from_dict(d) else: return Content.from_dict(d) else: return super().from_dict(d) def get_hash(self, hash_name): if hash_name not in DEFAULT_ALGORITHMS: raise ValueError('{} is not a valid hash name.'.format(hash_name)) return getattr(self, hash_name) def hashes(self) -> Dict[str, bytes]: """Returns a dictionary {hash_name: hash_value}""" return {algo: getattr(self, algo) for algo in DEFAULT_ALGORITHMS} @attr.s(frozen=True) class Content(BaseContent): sha1 = attr.ib( type=bytes, validator=type_validator()) sha1_git = attr.ib( type=Sha1Git, validator=type_validator()) sha256 = attr.ib( type=bytes, validator=type_validator()) blake2s256 = attr.ib( type=bytes, validator=type_validator()) length = attr.ib( type=int, validator=type_validator()) status = attr.ib( type=str, validator=attr.validators.in_(['visible', 'hidden']), default='visible') data = attr.ib( type=Optional[bytes], validator=type_validator(), default=None) ctime = attr.ib( type=Optional[datetime.datetime], validator=type_validator(), default=None) @length.validator def check_length(self, attribute, value): """Checks the length is positive.""" if value < 0: raise ValueError('Length must be positive.') def to_dict(self): content = super().to_dict() if content['data'] is None: del content['data'] return content @classmethod def from_data(cls, data, status='visible') -> 'Content': """Generate a Content from a given `data` byte string. This populates the Content with the hashes and length for the data passed as argument, as well as the data itself. """ d = cls._hash_data(data) d['status'] = status return cls(**d) @classmethod def from_dict(cls, d): return super().from_dict(d, use_subclass=False) def with_data(self) -> 'Content': """Loads the `data` attribute; meaning that it is guaranteed not to be None after this call. This call is almost a no-op, but subclasses may overload this method to lazy-load data (eg. from disk or objstorage).""" if self.data is None: raise MissingData('Content data is None.') return self @attr.s(frozen=True) class SkippedContent(BaseContent): sha1 = attr.ib( type=Optional[bytes], validator=type_validator()) sha1_git = attr.ib( type=Optional[Sha1Git], validator=type_validator()) sha256 = attr.ib( type=Optional[bytes], validator=type_validator()) blake2s256 = attr.ib( type=Optional[bytes], validator=type_validator()) length = attr.ib( type=Optional[int], validator=type_validator()) status = attr.ib( type=str, validator=attr.validators.in_(['absent'])) reason = attr.ib( type=Optional[str], validator=type_validator(), default=None) origin = attr.ib( type=Optional[str], validator=type_validator(), default=None) ctime = attr.ib( type=Optional[datetime.datetime], validator=type_validator(), default=None) @reason.validator def check_reason(self, attribute, value): """Checks the reason is full if status != absent.""" assert self.reason == value if value is None: raise ValueError('Must provide a reason if content is absent.') @length.validator def check_length(self, attribute, value): """Checks the length is positive or -1.""" if value < -1: raise ValueError('Length must be positive or -1.') def to_dict(self): content = super().to_dict() if content['origin'] is None: del content['origin'] return content @classmethod def from_data(cls, data, reason: str) -> 'SkippedContent': """Generate a SkippedContent from a given `data` byte string. This populates the SkippedContent with the hashes and length for the data passed as argument. You can use `attr.evolve` on such a generated content to nullify some of its attributes, e.g. for tests. """ d = cls._hash_data(data) del d['data'] d['status'] = 'absent' d['reason'] = reason return cls(**d) @classmethod def from_dict(cls, d): - d2 = d - d = d.copy() - if d.pop('data', None) is not None: - raise ValueError('SkippedContent has no "data" attribute %r' % d2) - return super().from_dict(d, use_subclass=False) + d2 = d.copy() + if d2.pop('data', None) is not None: + raise ValueError('SkippedContent has no "data" attribute %r' % d) + return super().from_dict(d2, use_subclass=False)