-git-mirror: Sync your git repositories
-=======================================
-
-Introduction
-------------
-
-git-mirror_ is a tool to keep multiple git repositories of the same project in
-sync. Whenever something is pushed to any repository, the commits will
-immediately be forwarded to all the others. The tool assumes to run on a server
-hosting one of these repositories - so there has to be at least one you can
-control. A typical use-case would be your own gitolite_ installation, that you
-want to keep in sync with GitHub_.
-
-.. _git-mirror: https://www.ralfj.de/projects/git-mirror
-.. _gitolite: http://gitolite.com/gitolite/index.html
-.. _GitHub: https://github.com/
-
-Setup (gitolite)
-----------------
-
-This describes how you set up git-mirror on a server running gitolite. For other
-git hosting software, please consult the respective documentation on adding git
-hooks. I will assume that gitolite is installed to ``/home/git/gitolite``, that
-the repositories are sitting in ``/home/git/repositories``, and that git-mirror
-has been cloned to ``/home/git/git-mirror``.
-
-First of all, you need to create a file called ``git-mirror.conf`` in the
-``git-mirror`` directory. For now, it only needs to contain a single line::
-
- mail-sender = git@example.com
-
-We will also need to add hooks to the git repositories you want to sync. The
-easiest way to manage these hooks is to put them into your ``gitolite-admin``
-repository, so enable the following line in ``/home/git/.gitolite.rc``::
-
- LOCAL_CODE => "$rc{GL_ADMIN_BASE}/local",
-
-Make sure you read the `security note
-<http://gitolite.com/gitolite/non-core.html#pushcode>`_ concerning this
-configuration.
-
-Now add a file called ``local/hooks/repo-specific/git-mirror`` to your
-``gitolite-admin`` repository, make ii executable, and give it the following
-content::
-
- #!/bin/sh
- exec ~/git-mirror/githook.py
-
-For every repository you want to be synced, you can enable the hook by adding
-the following line to its configuration in ``conf/gitolite.conf``::
-
- option hook.post-receive = git-mirror
-
-(If you need multiple hooks here, you can separate them by spaces.)
-
-Finally, you need to tell git-mirror where to sync incoming changes to this
-repository to. Add a block like the following to ``git-mirror.conf``::
-
- [repo-name]
- owner = email@example.com
- local = /home/git/repositories/repo-name.git
- deploy-key = ssh-key
- mirror-a = git@server2.example.com:repo-name.git
- mirror-b = git@server2.example.org:the-repo.git
-
-Here, ``local`` has to be set to the path where the repository is stored
-locally. ``deploy-key`` is the name of the SSH key used for pushing the changes
-to other repositories. ``owner`` is the e-mail-address that errors occurring
-during synchronization are sent to. And finally, the URLs to push to are given
-by ``mirror-<something>``. If these other servers also run gitolite and have a
-symmetric setup, then no matter where a change is pushed, git-mirror will
-forward it to all the other repositories.
-
-Setup (GitHub)
---------------
-
-If one of the to-be-synced repositories is on GitHub, you can obviously not use
-the procedure above to sync changes that are arriving at GitHub, to the other
-repositories. Instead, we will use a webhook, such that GitHub tells your server
-that a change happened, and then your server can pull the changes to its local
-repository and synchronize all the others. This assumes that the server running
-the webhook also hosts one of the copies of the git repository.
-
-First of all, you will have to configure your webserver to run ``webhook.py`` as
-CGI script. Consult the webserver documentation for more details.
-
-Secondly, ``webhook.py`` needs to be able to find the main git-mirror scripts,
-and it needs to be able to execute them as the ``git`` user. For the first
-point, open ``webhook.py`` and change ``webhook_core`` to point to the file
-``webhook-core.py`` in your git-mirror clone. If your installation matches the
-paths I used above, that should already be the case. For the second point,
-``webhook.py`` is using ``sudo`` to elevate its privileges. You need to tell
-``sudo`` that this is all right, by creating a file
-``/etc/sudoers.d/git-mirror`` with content::
-
- www-data ALL=(git) NOPASSWD: /home/git/git-mirror/webhook-core.py
-
-Now, if you visit ``https://example.com/git-mirror/webhook.py`` (replace with
-your URL), the script should run and tell you ``Repository missing or not
-found.``.
-
-The next step is to add this as a webhook to the GitHub repository you want to
-sync with, to create a fresh SSH key and configure it as deployment key for the
-repository, and to configure git-mirror accordingly. For additional security,
-one should also configure a shared HMAC secret, such that the webhook can verify
-that the data indeed comes from GitHub.
-
-To make your job easier, there is a script ``github-add-hooks.py`` that can do
-all this for you. It assumes that the repository exists on the GitHub side, but
-has not yet been configured for git-mirror at all.
-
-To give the script access to your repositories, you need to create an access
-token for it. Go to "Personal Access Tokens" in your GitHub configuration, and
-create a new token with the permissions ``admin:repo_hook`` and ``public_repo``.
-Add the token and the webhook URL to the top part of ``git-mirror.conf`` (right
-below ``mail-sender``)::
-
- github-token = pastethetokenhere
- webhook-url = https://example.com/git-mirror/webhook.py
-
-Now you can call the automatic setup script as follows::
-
- ./github-add-hooks.py -o UserName -e email@example.com \
- -l ~/repositories/repo-name.git/ -n github-repo-name
-
-Notice that the username is case-sensitive! This will do all the setup on the
-GitHub side, and it will add an appropriate configuration block to your local
-``git-mirror.conf``. You still have to manually add the local git hook to
-gitolite. Once you are done, any push happening to either gitolite or GitHub
-will be visible on the other side immediately. This applies even to pull
-requests that you merge in the GitHub web interface.
-
-Source, License
----------------
-
-You can find the sources in the `git repository`_ (also available `on GitHub`_).
-Guess what, the two are synced with this tool ;-) . They are provided under a
-`2-clause BSD license`_. See the file ``LICENSE-BSD`` for more details.
-
-.. _git repository: http://www.ralfj.de/git/git-mirror.git
-.. _on GitHub: https://github.com/RalfJung/git-mirror
-.. _2-clause BSD license: http://opensource.org/licenses/bsd-license.php
-
-Contact
--------
-
-If you found a bug, or want to leave a comment, please
-`send me a mail <mailto:post-AT-ralfj-DOT-de>`_. I'm also happy about pull
-requests :)
projects / git-mirror.git / commitdiff