Python bindings for libgit2.
pygit2 - libgit2 bindings in Python
pygit2 is a set of Python bindings to the libgit2 linkable C Git library. The supported versions of Python are 2.6, 2.7, 3.1 and 3.2
Through this text Python 3 is used for the inline examples. Also, the Python 3 terminology is used (for instance we say text strings instead of unicode strings).
INSTALLING AND RUNNING
First you need to install the latest version of libgit2. You can find platform-specific instructions to build the library in the libgit2 website:
Also, make sure you have Python 2.6+ installed together with the Python development headers.
When those are installed, you can install pygit2:
$ git clone git://github.com/libgit2/pygit2.git $ cd pygit2 $ python setup.py install $ python setup.py test
Building on Windows
pygit2 expects to find the libgit2 installed files in the directory specified in the LIBGIT2 environment variable.
In addition, make sure that libgit2 is build in “__cdecl” mode. The following recipe shows you how to do it, assuming you’re working from a bash shell:
$ export LIBGIT2=C:/Dev/libgit2 $ git clone git://github.com/libgit2/libgit2.git $ cd libgit2 $ mkdir build $ cd build $ cmake .. -DSTDCALL=OFF -DCMAKE_INSTALL_PREFIX=$LIBGIT2 -G "Visual Studio 9 2008" $ cmake --build . --config release --target install $ ctest -v
At this point, you’re ready to execute the generic pygit2 installation steps described above.
Everything starts by opening an existing repository:
>>> from pygit2 import Repository >>> repo = Repository('pygit2/.git')
Or by creating a new one:
>>> from pygit2 import init_repository >>> bare = False >>> repo = init_repository('test', bare)
These are the basic attributes of a repository:
Repository.path -- path to the Git repository Repository.workdir -- path to the working directory, None in the case of a bare repo
In the first place Git is a key-value storage system. The values stored are called objects, there are four types (commits, trees, blobs and tags), for each type pygit2 has a Python class:
# Get the last commit >>> head = repo.head # Show commits and trees >>> commit <pygit2.Commit object at 0x7f9d2f3000b0> >>> commit.tree <pygit2.Tree object at 0x7f9d2f3000f0>
These four classes (Commit, Tree, Blob and Tag) inherit from the Object base class, which provides shared behaviour. A Git object is identified by a unique object id, which is a binary byte string; this is often represented as an hexadecimal text string:
>>> commit.oid b'x\xde\xb5W\x8d\x01<\xdb\xdf\x08o\xa1\xd1\xa3\xe7\xd9\x82\xe8\x88\x8f' >>> commit.hex '78deb5578d013cdbdf086fa1d1a3e7d982e8888f'
The API of pygit2 accepts both the raw object id and its hexadecimal representation, the difference is done based on its type (a byte or a text string).
This is the common interface for all Git objects:
Object.type -- one of the GIT_OBJ_COMMIT, GIT_OBJ_TREE, GIT_OBJ_BLOB or GIT_OBJ_TAG constants Object.oid -- the object id, a byte string 20 bytes long Object.hex -- hexadecimal representation of the object id, a text string 40 chars long Object.read_raw() -- returns the byte string with the raw contents of the of the object
Objects can not be modified once they have been created.
A commit is a snapshot of the working dir with meta informations like author, committer and others.:
Commit.author -- the author of the commit Commit.committer -- the committer of the commit Commit.message -- the message, a text string Commit.tree -- the tree object attached to the commit Commit.parents -- the list of parent commits
The author and committer attributes of commit objects are Signature objects:
>>> commit.author <pygit2.Signature object at 0x7f75e9b1f5f8>
This is their interface:
Signature.name -- person's name Signature.email -- person's email address Signature.time -- unix time Signature.offset -- offset from utc in minutes
Commits can be created by calling the create_commit method of the repository with the following parameters:
>>> from time import time >>> author = Signature('Alice Author', 'firstname.lastname@example.org', time(), 0) >>> committer = Signature('Cecil Committer', 'email@example.com', time(), 0) >>> tree = repo.TreeBuilder().write() >>> repo.create_commit( ... 'refs/heads/master', # the name of the reference to update ... author, committer, 'one line commit message\n\ndetailed commit message', ... tree, # binary string representing the tree object ID ...  # list of binary strings representing parents of the new commit ... ) '#\xe4<u\xfe\xd6\x17\xa0\xe6\xa2\x8b\xb6\xdc35$\xcf-\x8b~'
A tree is a sorted collection of tree entries. It is similar to a folder or directory in a file system. Each entry points to another tree or a blob. A tree can be iterated, and partially implements the sequence and mapping interfaces:
# Number of entries >>> tree = commit.tree >>> len(tree) 6 # Iteration >>> for entry in tree: ... print(entry.hex, entry.name) ... 7151ca7cd3e59f3eab19c485cfbf3cb30928d7fa .gitignore c36f4cf1e38ec1bb9d9ad146ed572b89ecfc9f18 COPYING 32b30b90b062f66957d6790c3c155c289c34424e README.md c87dae4094b3a6d10e08bc6c5ef1f55a7e448659 pygit2.c 85a67270a49ef16cdd3d328f06a3e4b459f09b27 setup.py 3d8985bbec338eb4d47c5b01b863ee89d044bd53 test # Get an entry by name >>> entry = tree['pygit2.c'] >>> entry <pygit2.TreeEntry object at 0xcc10f0> # Get the object the entry points to >>> blob = repo[entry.oid] >>> blob <pygit2.Blob object at 0xcc12d0>
This is the interface of a tree entry:
TreeEntry.name -- name of the tree entry TreeEntry.oid -- the id of the git object TreeEntry.hex -- hexadecimal representation of the oid TreeEntry.attributes -- the Unix file attributes TreeEntry.to_object() -- returns the git object (equivalent to repo[entry.oid])
A diff shows the changes between trees, an index or the working dir:
# Diff two trees >>> t0 = repo.head.tree >>> t1 = repo.head.parents >>> diff = t0.diff(t1) >>> diff # Diff a tree with the index >>> tree = repo.head.tree >>> diff = tree.diff(repo.index) # Diff a tree with the current working dir >>> tree = repo.head.tree >>> diff = tree.diff()
The interface for a diff:
Diff.changes -- Dict of 'files' and 'hunks' for every change Diff.patch -- a patch for every changeset Diff.merge -- Merge two Diffs
A blob is equivalent to a file in a file system.:
# create a blob out of memory >>> oid = repo.create_blob('foo bar') >>> blob = repo[oid] Blob.data -- the contents of the blob, a byte string
>>> all_refs = repo.listall_references() >>> master_ref = repo.lookup_reference("refs/heads/master") >>> commit = repo[master_ref.oid]
>>> head = repo.lookup_reference('refs/heads/master') >>> for entry in head.log(): ... print(entry.message)
The interface for RefLogEntry:
RefLogEntry.committer -- Signature of Committer RefLogEntry.message -- the message of the RefLogEntry RefLogEntry.oid_old -- oid of old reference RefLogEntry.oid_new -- oid of new reference
You can iterate through the revision history with repo.walk:
>>> from pygit2 import GIT_SORT_TIME >>> for commit in repo.walk(oid, GIT_SORT_TIME): ... print(commit.hex)
The index file
>>> index = repo.index >>> index.read() >>> oid = index['path/to/file'].oid # from path to object id >>> blob = repo[oid] # from object id to object
Iterate over all entries of the index:
>>> for entry in index: ... print entry.path, entry.hex
>>> index.add('path/to/file') # git add >>> del index['path/to/file'] # git rm >>> index.write() # don't forget to save the changes
Inspect the status of the repository:
>>> from pygit2 import GIT_STATUS_CURRENT >>> status = repo.status() >>> for filepath, flags in status.items(): ... if flags != GIT_STATUS_CURRENT: ... print "Filepath %s isn't clean" % filepath
Fork libgit2/pygit2 on GitHub, make it awesomer (preferably in a branch named for the topic), send a pull request.
GPLv2 with linking exception. See COPYING for more details.