# base.py
# Copyright (C) 2008, 2009 Michael Trier (mtrier@gmail.com) and contributors
#
# This module is part of GitPython and is released under
# the BSD License: http://www.opensource.org/licenses/bsd-license.php
from util import get_object_type_by_name
from git.util import (
hex_to_bin,
bin_to_hex,
dirname,
basename,
LazyMixin,
join_path_native,
stream_copy
)
from git.db.interface import RepositoryPathsMixin
from git.exc import UnsupportedOperation
from git.typ import ObjectType
_assertion_msg_format = "Created object %r whose python type %r disagrees with the acutal git object type %r"
__all__ = ("Object", "IndexObject")
class Object(LazyMixin):
"""Implements an Object which may be Blobs, Trees, Commits and Tags"""
NULL_HEX_SHA = '0' * 40
NULL_BIN_SHA = '\0' * 20
TYPES = (ObjectType.blob, ObjectType.tree, ObjectType.commit, ObjectType.tag)
__slots__ = ("odb", "binsha", "size")
type = None # to be set by subclass
type_id = None # to be set by subclass
def __init__(self, odb, binsha):
"""Initialize an object by identifying it by its binary sha.
All keyword arguments will be set on demand if None.
:param odb: repository this object is located in
:param binsha: 20 byte SHA1"""
super(Object, self).__init__()
self.odb = odb
self.binsha = binsha
assert len(binsha) == 20, "Require 20 byte binary sha, got %r, len = %i" % (binsha, len(binsha))
@classmethod
def new(cls, odb, id):
"""
:return: New Object instance of a type appropriate to the object type behind
id. The id of the newly created object will be a binsha even though
the input id may have been a Reference or Rev-Spec
:param id: reference, rev-spec, or hexsha
:note: This cannot be a __new__ method as it would always call __init__
with the input id which is not necessarily a binsha."""
return odb.rev_parse(str(id))
@classmethod
def new_from_sha(cls, odb, sha1):
"""
:return: new object instance of a type appropriate to represent the given
binary sha1
:param sha1: 20 byte binary sha1"""
if sha1 == cls.NULL_BIN_SHA:
# the NULL binsha is always the root commit
return get_object_type_by_name('commit')(odb, sha1)
# END handle special case
oinfo = odb.info(sha1)
inst = get_object_type_by_name(oinfo.type)(odb, oinfo.binsha)
inst.size = oinfo.size
return inst
def _set_cache_(self, attr):
"""Retrieve object information"""
if attr == "size":
oinfo = self.odb.info(self.binsha)
self.size = oinfo.size
# assert oinfo.type == self.type, _assertion_msg_format % (self.binsha, oinfo.type, self.type)
else:
super(Object, self)._set_cache_(attr)
def __eq__(self, other):
""":return: True if the objects have the same SHA1"""
if not hasattr(other, 'binsha'):
return False
return self.binsha == other.binsha
def __ne__(self, other):
""":return: True if the objects do not have the same SHA1 """
if not hasattr(other, 'binsha'):
return True
return self.binsha != other.binsha
def __hash__(self):
""":return: Hash of our id allowing objects to be used in dicts and sets"""
return hash(self.binsha)
def __str__(self):
""":return: string of our SHA1 as understood by all git commands"""
return bin_to_hex(self.binsha)
def __repr__(self):
""":return: string with pythonic representation of our object"""
return '' % (self.__class__.__name__, self.hexsha)
@property
def hexsha(self):
""":return: 40 byte hex version of our 20 byte binary sha"""
return bin_to_hex(self.binsha)
@property
def data_stream(self):
""" :return: File Object compatible stream to the uncompressed raw data of the object
:note: returned streams must be read in order"""
return self.odb.stream(self.binsha)
def stream_data(self, ostream):
"""Writes our data directly to the given output stream
:param ostream: File object compatible stream object.
:return: self"""
istream = self.odb.stream(self.binsha)
stream_copy(istream, ostream)
return self
class IndexObject(Object):
"""Base for all objects that can be part of the index file , namely Tree, Blob and
SubModule objects"""
__slots__ = ("path", "mode")
# for compatability with iterable lists
_id_attribute_ = 'path'
def __init__(self, odb, binsha, mode=None, path=None):
"""Initialize a newly instanced IndexObject
:param odb: is the object database we are located in
:param binsha: 20 byte sha1
:param mode: is the stat compatible file mode as int, use the stat module
to evaluate the infomration
:param path:
is the path to the file in the file system, relative to the git repository root, i.e.
file.ext or folder/other.ext
:note:
Path may not be set of the index object has been created directly as it cannot
be retrieved without knowing the parent tree."""
super(IndexObject, self).__init__(odb, binsha)
if mode is not None:
self.mode = mode
if path is not None:
self.path = path
def __hash__(self):
""":return:
Hash of our path as index items are uniquely identifyable by path, not
by their data !"""
return hash(self.path)
def _set_cache_(self, attr):
if attr in IndexObject.__slots__:
# they cannot be retrieved lateron ( not without searching for them )
raise AttributeError(
"path and mode attributes must have been set during %s object creation" % type(self).__name__)
else:
super(IndexObject, self)._set_cache_(attr)
# END hanlde slot attribute
@property
def name(self):
""":return: Name portion of the path, effectively being the basename"""
return basename(self.path)
@property
def abspath(self):
"""
:return:
Absolute path to this index object in the file system ( as opposed to the
.path field which is a path relative to the git repository ).
The returned path will be native to the system and contains '\' on windows.
:raise UnsupportedOperation: if underlying odb does not support the required method to obtain a working dir"""
# TODO: Here we suddenly need something better than a plain object database
# which indicates our odb should better be named repo !
root = ''
if isinstance(self.odb, RepositoryPathsMixin):
root = self.odb.working_tree_dir
else:
raise UnsupportedOperation("Cannot provide absolute path from a database without Repository path support")
# END handle odb type
return join_path_native(root, self.path)