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
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