openstack/deb-python-pygit2
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J. David Ibáñez
2014-10-30 13:45:54 +01:00
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docs/install.rst
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@@ -13,67 +13,73 @@ Installation
Requirements
============
- Python 2.7, 3.2, 3.3, 3.4 or pypy.
Including the development headers.
- Libgit2 v0.21.1
- Python 2.7, 3.2+ or pypy (including the development headers)
- Libgit2 v0.21.1+
- cffi 0.8.1+
.. warning::
One common mistake users do is to choose incompatible versions of libgit2 and
pygit2. Be sure to use the latest release of both, double check the versions do
match before filing a bug report.
One common mistake users do is to choose incompatible versions of libgit2
and pygit2. See below for a reference table of compatible versions. Double
check the versions do match before filing a bug report.
.. note::
Version numbers
---------------
The version of pygit2 is composed of three numbers separated by dots
|lq| *major.minor.micro* |rq|, where the first two numbers
|lq| *major.minor* |rq| match the first two numbers of the libgit2 version,
while the last number |lq| *.micro* |rq| auto-increments independently.
The version number of pygit2 is composed of three numbers separated by dots
|lq| *major.minor.micro* |rq|, where the first two numbers
|lq| *major.minor* |rq| match the first two numbers of the libgit2 version,
while the last number |lq| *.micro* |rq| auto-increments independently.
As illustration see this table of compatible releases:
As illustration see this table of compatible releases:
+-----------+-------------------------------+------------------------------+
|**libgit2**|0.21.1 |0.20.0 |
+-----------+-------------------------------+------------------------------+
|**pygit2** |0.21.0, 0.21.1, 0.21.2, 0.21.3 |0.20.0, 0.20.1, 0.20.2, 0.20.3|
+-----------+-------------------------------+------------------------------+
+-----------+-------------------------------+------------------------------+--------------+
|**libgit2**|0.21.1, 0.21.2 |0.20.0 |0.19.0 |
+-----------+-------------------------------+------------------------------+--------------+
|**pygit2** |0.21.0, 0.21.1, 0.21.2, 0.21.3 |0.20.0, 0.20.1, 0.20.2, 0.20.3|0.19.0, 0.19.1|
+-----------+-------------------------------+------------------------------+--------------+
**Warning!** Backwards compatibility is not guaranteed even between micro
releases. Please check the release notes for incompatible changes before
upgrading to a new release.
.. warning::
Backwards compatibility is not guaranteed even between micro releases.
Please check the release notes for incompatible changes before upgrading to
a new release.
Quick install
=============
This works for me, it may work for you:
To install the latest version of libgit2 system wide, in the ``/usr/local``
directory, do:
.. code-block:: sh
$ wget https://github.com/libgit2/libgit2/archive/v0.21.1.tar.gz
$ tar xzf v0.21.1.tar.gz
$ cd libgit2-0.21.1/
$ wget https://github.com/libgit2/libgit2/archive/v0.21.2.tar.gz
$ tar xzf v0.21.2.tar.gz
$ cd libgit2-0.21.2/
$ cmake .
$ make
$ sudo make install
If this does not work for you, check the detailed instructions on building
libgit2 in various platforms, see
https://libgit2.github.com/docs/guides/build-and-link/
.. seealso::
Once libgit2 is installed, deploying pygit2 should be a snap:
For detailed instructions on building libgit2 check
https://libgit2.github.com/docs/guides/build-and-link/
Now install pygit2, and then verify it is correctly installed:
.. code-block:: sh
$ pip install pygit2
...
$ python -c 'import pygit2'
Troobleshooting
===============
---------------
You may get an error like this one:
The verification step may fail if the dynamic linker does not find the libgit2
library:
.. code-block:: sh
@@ -84,70 +90,40 @@ You may get an error like this one:
from _pygit2 import *
ImportError: libgit2.so.0: cannot open shared object file: No such file or directory
It means the linker is not able to find the libgit2 library.
This happens for instance in Ubuntu: the libgit2 library is installed within
This happens for instance in Ubuntu, the libgit2 library is installed within
the ``/usr/local/lib`` directory, but the linker does not look for it there. To
fix this call ``ldconfig`` between the installation of libgit2 and the
installation of pygit2:
fix this call ``ldconfig``:
.. code-block:: sh
...
$ cmake .
$ make
$ sudo make install
...
$ sudo ldconfig
...
$ pip install pygit2
$ python -c 'import pygit2'
Now it should work. If it does not...
Advanced: the runpath
---------------------
If it does not work yet, you can always instruct pygit2 to search for libraries
in some extra paths:
.. code-block:: sh
$ export LIBGIT2="/usr/local"
$ export LDFLAGS="-Wl,-rpath='$LIBGIT2/lib',--enable-new-dtags $LDFLAGS"
$ pip install pygit2
This compiles the pygit2 libraries with a ``RUNPATH``, which bakes extra
library search paths directly into the binaries (see the `ld man page`_ for
details). With ``RUNPATH`` compiled in, you won't have to use
``LD_LIBRARY_PATH``. You can check to ensure ``RUNPATH`` was set with
readelf_:
.. code-block:: sh
$ readelf --dynamic build/lib.linux-x86_64-3.2/_pygit2.cpython-32.so | grep PATH
0x000000000000000f (RPATH) Library rpath: [/usr/local/lib]
0x000000000000001d (RUNPATH) Library runpath: [/usr/local/lib]
.. _Shared libraries: http://tldp.org/HOWTO/Program-Library-HOWTO/shared-libraries.html
.. _ld man page: http://linux.die.net/man/1/ld
.. _readelf: http://www.gnu.org/software/binutils/
If it still does not work, please open an issue at
https://github.com/libgit2/pygit2/issues, I would like to know about it.
The LIBGIT2 environment variable
================================
Build options
=============
If libgit2 is installed in some non standard location, you will have to set the
``LIBGIT2`` environment variable before installing pygit2. This variables tells
pygit2 where libgit2 is installed.
``LIBGIT2`` -- If you install libgit2 in an unusual place, you will need to set
the ``LIBGIT2`` environment variable before installing pygit2. This variable
tells pygit2 where libgit2 is installed. We will see a concrete example later,
when explaining how to install libgit2 within a virtual environment.
``LIBGIT2_LIB`` -- This is a more rarely used build option, it allows to
override the library directory where libgit2 is installed, useful if different
from from ``$LIBGIT2/lib``.
Use case: libgit2 within a Virtualenv
-------------------------------------
libgit2 within a virtual environment
====================================
A use case for this is if you want to install libgit2 inside a virtualenv, so
you may have several virtualenvs with different versions of libgit2/pygit2,
isolated from each other. Or maybe you just don't have root access to install
libgit2 in the system.
This is how to install both libgit2 and pygit2 within a virtual environment.
This is useful if you don't have root acces to install libgit2 system wide.
Or if you wish to have different versions of libgit2/pygit2 installed in
different virtual environments, isolated from each other.
Create the virtualenv, activate it, and set the ``LIBGIT2`` environment
variable:
@@ -162,9 +138,9 @@ Install libgit2 (see we define the installation prefix):
.. code-block:: sh
$ wget https://github.com/libgit2/libgit2/archive/v0.21.1.tar.gz
$ tar xzf v0.21.1.tar.gz
$ cd libgit2-0.21.1/
$ wget https://github.com/libgit2/libgit2/archive/v0.21.2.tar.gz
$ tar xzf v0.21.2.tar.gz
$ cd libgit2-0.21.2/
$ cmake . -DCMAKE_INSTALL_PREFIX=$LIBGIT2
$ make
$ make install
@@ -173,10 +149,38 @@ Install pygit2:
.. code-block:: sh
$ export LDFLAGS="-Wl,-rpath='$LIBGIT2/lib',--enable-new-dtags $LDFLAGS"
$ pip install pygit2
$ python -c 'import pygit2'
Building on Windows
The run-path
------------------------------------------
Did you notice we set the `rpath <http://en.wikipedia.org/wiki/Rpath>`_ before
installing pygit2? Since libgit2 is installed in a non standard location, the
dynamic linker will not find it at run-time, and ``lddconfig`` will not help
this time.
So you need to either set ``LD_LIBRARY_PATH`` before using pygit2, like:
.. code-block:: sh
$ export LD_LIBRARY_PATH=$LIBGIT2/lib
$ python -c 'import pygit2'
Or, like we have done in the instructions above, use the `rpath
<http://en.wikipedia.org/wiki/Rpath>`_, it hard-codes extra search paths within
the pygit2 extension modules, so you don't need to set ``LD_LIBRARY_PATH``
everytime. Verify yourself if curious:
.. code-block:: sh
$ readelf --dynamic lib/python2.7/site-packages/pygit2-0.21.3-py2.7-linux-x86_64.egg/pygit2_cffi.so | grep PATH
0x000000000000001d (RUNPATH) Library runpath: [/tmp/venv/lib]
Installing on Windows
===================================
pygit2 expects to find the libgit2 installed files in the directory specified
@@ -189,14 +193,20 @@ from a bash shell:
.. code-block:: sh
$ export LIBGIT2=C:/Dev/libgit2
$ wget https://github.com/libgit2/libgit2/archive/v0.21.1.tar.gz
$ tar xzf v0.21.1.tar.gz
$ cd libgit2-0.21.1/
$ mkdir build
$ cd build
$ cmake .. -DSTDCALL=OFF -DCMAKE_INSTALL_PREFIX=$LIBGIT2 -G "Visual Studio 9 2008"
$ wget https://github.com/libgit2/libgit2/archive/v0.21.2.tar.gz
$ tar xzf v0.21.2.tar.gz
$ cd libgit2-0.21.2/
$ 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.
Installing on OS X
===================================
.. note::
Help wanted to write this section, please make a pull request
https://github.com/libgit2/pygit2/pulls