from mmap import mmap import re import time as _time from git.compat import defenc from git.objects.util import ( parse_date, Serializable, altz_to_utctz_str, ) from git.util import ( Actor, LockedFD, LockFile, assure_directory_exists, to_native_path, bin_to_hex, file_contents_ro_filepath, ) import os.path as osp # typing ------------------------------------------------------------------ from typing import Iterator, List, Tuple, Union, TYPE_CHECKING from git.types import PathLike if TYPE_CHECKING: from git.refs import SymbolicReference from io import BytesIO from git.config import GitConfigParser, SectionConstraint # NOQA # ------------------------------------------------------------------------------ __all__ = ["RefLog", "RefLogEntry"] class RefLogEntry(Tuple[str, str, Actor, Tuple[int, int], str]): """Named tuple allowing easy access to the revlog data fields""" _re_hexsha_only = re.compile("^[0-9A-Fa-f]{40}$") __slots__ = () def __repr__(self) -> str: """Representation of ourselves in git reflog format""" return self.format() def format(self) -> str: """:return: a string suitable to be placed in a reflog file""" act = self.actor time = self.time return "{} {} {} <{}> {!s} {}\t{}\n".format( self.oldhexsha, self.newhexsha, act.name, act.email, time[0], altz_to_utctz_str(time[1]), self.message, ) @property def oldhexsha(self) -> str: """The hexsha to the commit the ref pointed to before the change""" return self[0] @property def newhexsha(self) -> str: """The hexsha to the commit the ref now points to, after the change""" return self[1] @property def actor(self) -> Actor: """Actor instance, providing access""" return self[2] @property def time(self) -> Tuple[int, int]: """time as tuple: * [0] = int(time) * [1] = int(timezone_offset) in time.altzone format""" return self[3] @property def message(self) -> str: """Message describing the operation that acted on the reference""" return self[4] @classmethod def new( cls, oldhexsha: str, newhexsha: str, actor: Actor, time: int, tz_offset: int, message: str, ) -> "RefLogEntry": # skipcq: PYL-W0621 """:return: New instance of a RefLogEntry""" if not isinstance(actor, Actor): raise ValueError("Need actor instance, got %s" % actor) # END check types return RefLogEntry((oldhexsha, newhexsha, actor, (time, tz_offset), message)) @classmethod def from_line(cls, line: bytes) -> "RefLogEntry": """:return: New RefLogEntry instance from the given revlog line. :param line: line bytes without trailing newline :raise ValueError: If line could not be parsed""" line_str = line.decode(defenc) fields = line_str.split("\t", 1) if len(fields) == 1: info, msg = fields[0], None elif len(fields) == 2: info, msg = fields else: raise ValueError("Line must have up to two TAB-separated fields." " Got %s" % repr(line_str)) # END handle first split oldhexsha = info[:40] newhexsha = info[41:81] for hexsha in (oldhexsha, newhexsha): if not cls._re_hexsha_only.match(hexsha): raise ValueError("Invalid hexsha: %r" % (hexsha,)) # END if hexsha re doesn't match # END for each hexsha email_end = info.find(">", 82) if email_end == -1: raise ValueError("Missing token: >") # END handle missing end brace actor = Actor._from_string(info[82 : email_end + 1]) time, tz_offset = parse_date(info[email_end + 2 :]) # skipcq: PYL-W0621 return RefLogEntry((oldhexsha, newhexsha, actor, (time, tz_offset), msg)) class RefLog(List[RefLogEntry], Serializable): """A reflog contains RefLogEntrys, each of which defines a certain state of the head in question. Custom query methods allow to retrieve log entries by date or by other criteria. Reflog entries are ordered, the first added entry is first in the list, the last entry, i.e. the last change of the head or reference, is last in the list.""" __slots__ = ("_path",) def __new__(cls, filepath: Union[PathLike, None] = None) -> "RefLog": inst = super(RefLog, cls).__new__(cls) return inst def __init__(self, filepath: Union[PathLike, None] = None): """Initialize this instance with an optional filepath, from which we will initialize our data. The path is also used to write changes back using the write() method""" self._path = filepath if filepath is not None: self._read_from_file() # END handle filepath def _read_from_file(self) -> None: try: fmap = file_contents_ro_filepath(self._path, stream=True, allow_mmap=True) except OSError: # it is possible and allowed that the file doesn't exist ! return # END handle invalid log try: self._deserialize(fmap) finally: fmap.close() # END handle closing of handle # { Interface @classmethod def from_file(cls, filepath: PathLike) -> "RefLog": """ :return: a new RefLog instance containing all entries from the reflog at the given filepath :param filepath: path to reflog :raise ValueError: If the file could not be read or was corrupted in some way""" return cls(filepath) @classmethod def path(cls, ref: "SymbolicReference") -> str: """ :return: string to absolute path at which the reflog of the given ref instance would be found. The path is not guaranteed to point to a valid file though. :param ref: SymbolicReference instance""" return osp.join(ref.repo.git_dir, "logs", to_native_path(ref.path)) @classmethod def iter_entries(cls, stream: Union[str, "BytesIO", mmap]) -> Iterator[RefLogEntry]: """ :return: Iterator yielding RefLogEntry instances, one for each line read sfrom the given stream. :param stream: file-like object containing the revlog in its native format or string instance pointing to a file to read""" new_entry = RefLogEntry.from_line if isinstance(stream, str): # default args return mmap on py>3 _stream = file_contents_ro_filepath(stream) assert isinstance(_stream, mmap) else: _stream = stream # END handle stream type while True: line = _stream.readline() if not line: return yield new_entry(line.strip()) # END endless loop @classmethod def entry_at(cls, filepath: PathLike, index: int) -> "RefLogEntry": """ :return: RefLogEntry at the given index :param filepath: full path to the index file from which to read the entry :param index: python list compatible index, i.e. it may be negative to specify an entry counted from the end of the list :raise IndexError: If the entry didn't exist .. note:: This method is faster as it only parses the entry at index, skipping all other lines. Nonetheless, the whole file has to be read if the index is negative """ with open(filepath, "rb") as fp: if index < 0: return RefLogEntry.from_line(fp.readlines()[index].strip()) # read until index is reached for i in range(index + 1): line = fp.readline() if not line: raise IndexError(f"Index file ended at line {i+1}, before given index was reached") # END abort on eof # END handle runup return RefLogEntry.from_line(line.strip()) # END handle index def to_file(self, filepath: PathLike) -> None: """Write the contents of the reflog instance to a file at the given filepath. :param filepath: path to file, parent directories are assumed to exist""" lfd = LockedFD(filepath) assure_directory_exists(filepath, is_file=True) fp = lfd.open(write=True, stream=True) try: self._serialize(fp) lfd.commit() except Exception: # on failure it rolls back automatically, but we make it clear lfd.rollback() raise # END handle change @classmethod def append_entry( cls, config_reader: Union[Actor, "GitConfigParser", "SectionConstraint", None], filepath: PathLike, oldbinsha: bytes, newbinsha: bytes, message: str, write: bool = True, ) -> "RefLogEntry": """Append a new log entry to the revlog at filepath. :param config_reader: configuration reader of the repository - used to obtain user information. May also be an Actor instance identifying the committer directly or None. :param filepath: full path to the log file :param oldbinsha: binary sha of the previous commit :param newbinsha: binary sha of the current commit :param message: message describing the change to the reference :param write: If True, the changes will be written right away. Otherwise the change will not be written :return: RefLogEntry objects which was appended to the log :note: As we are append-only, concurrent access is not a problem as we do not interfere with readers.""" if len(oldbinsha) != 20 or len(newbinsha) != 20: raise ValueError("Shas need to be given in binary format") # END handle sha type assure_directory_exists(filepath, is_file=True) first_line = message.split("\n")[0] if isinstance(config_reader, Actor): committer = config_reader # mypy thinks this is Actor | Gitconfigparser, but why? else: committer = Actor.committer(config_reader) entry = RefLogEntry( ( bin_to_hex(oldbinsha).decode("ascii"), bin_to_hex(newbinsha).decode("ascii"), committer, (int(_time.time()), _time.altzone), first_line, ) ) if write: lf = LockFile(filepath) lf._obtain_lock_or_raise() fd = open(filepath, "ab") try: fd.write(entry.format().encode(defenc)) finally: fd.close() lf._release_lock() # END handle write operation return entry def write(self) -> "RefLog": """Write this instance's data to the file we are originating from :return: self""" if self._path is None: raise ValueError("Instance was not initialized with a path, use to_file(...) instead") # END assert path self.to_file(self._path) return self # } END interface # { Serializable Interface def _serialize(self, stream: "BytesIO") -> "RefLog": write = stream.write # write all entries for e in self: write(e.format().encode(defenc)) # END for each entry return self def _deserialize(self, stream: "BytesIO") -> "RefLog": self.extend(self.iter_entries(stream)) # } END serializable interface return self