gitolite/doc/0-INSTALL.mkd

installing gitolite

[Update 2009-11-18: easy install now works from msysgit also!]

Gitolite is somewhat unusual as far as "server" software goes -- every userid on the server is a potential "gitolite host".

This document tells you how to install gitolite. After the install is done, you may want to see doc/2-admin.mkd for adding users, repos, etc.

Please note that gitolite depends heavily on proper ssh setup and pubkey based access. Sadly, most people don't know ssh as well as they think they do. To make matters worse, ssh problems in gitolite don't always look like ssh problems. Please read about ssh troubleshooting if you have any kind of trouble installing gitolite!

In this document:

• install methods
• user install
  • typical example run
  • advantages over the older install methods
  • disadvantages
  • upgrades
  • other notes
• system install / user setup
  • multiple gitolite instances
• next steps
• appendix A: server and client requirements for user install
  • server
  • install workstation
  • admin workstation(s)
• appendix B: uninstalling gitolite
• appendix C: NOTE TO PACKAGE MAINTAINERS

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install methods

There are 2 ways to install gitolite: The user-install mode was the traditional way, and is used when any of the following is true:

• you don't have root on your "server" (some types of hosting setups, many corporate paranoia setups ;-)
• your server distro does not have gitolite in its package repositories
• your server distro's package repositories have an old version of gitolite
• you want to stay current with the latest gitolite versions
• your server is not Linux (maybe AIX, or Solaris, etc.)

The "user install" section describes this method.

The system-install followed by user-setup mode is used when you (or someone who has root) has installed an RPM or DEB of gitolite and you intend to use that version. [Update 2010-04-27: there is now a script called gl-system-install that helps you do a system-install if your distribution does not yet have a package for gitolite; details below].

The "system install / user setup" section describes this method.

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user install

The gl-easy-install script makes installing very easy for this case. This script will setup everything on the server, but you have to run it on your workstation, NOT on the server!

Assumptions/pre-requisites:

• you have a server to host gitolite
• git is installed on that server (and so is perl)
• you have a userid on that server
• you have ssh-pubkey (password-less) login to that userid
  • if you have only password access, run ssh-keygen -t rsa to create a new keypair if needed, then run ssh-copy-id user@host. If you do not have ssh-copy-id, read doc/3-faq-tips-etc.mkd and look for ssh-copy-id in that file for instructions
• you have a clone or an archive of gitolite somewhere on your workstation
  • if you don't have one, just run git clone git://github.com/sitaramc/gitolite
• your workstation has bash (even msysgit bash will do)

Once you have all this, just cd to that clone and run src/gl-easy-install and follow the prompts! (Running it without any arguments shows you usage plus other useful info).

typical example run

A typical run for me is:

src/gl-easy-install -q git my.git.server sitaram

-q stands for "quiet" mode -- very minimal output, no verbose descriptions of what it is going to do, and no pauses unless absolutely needed. However, if you're doing this for the first time or you appreciate knowing what it is actually doing, I suggest you skip the -q.

A detailed transcript of an install done using this method can be found in doc/7-install-transcript.mkd.

advantages over the older install methods

• all ssh problems reduced to just one pre-requisite: enable ssh pubkey (password-less) access to the server from your workstation first
• the script takes care of all the server side work
• when done:
  • you get two different pubkeys (the original one for command line access as before, plus a new one, created by the script, for gitolite access)
  • you can admin gitolite by commit+push a "gitolite-admin" repo, just like gitosis (i.e., full "push to admin" power!)

disadvantages

• need a recent bash

upgrades

Upgrading gitolite is easy.

To upgrade, pull the latest "master" (or other) branch in your gitolite repo clone, then run the same exact command you ran to do the install, except you can leave out the last argument.

And you might want to add a -q to speed things up :-)

Note that this only upgrades the software. Unlike earlier versions, it does not touch the conf/gitolite.conf file or the contents of keydir in any way. I decided that it is not possible to safely let an upgrade do something meaningful with them -- fiddling with existing config files (as opposed to merely creating one which did not exist) is best left to a human.

other notes

• if you run src/gl-easy-install without the -q option, you will be given a chance to edit ~/.gitolite.rc. You can change any options (such as paths, for instance), but be sure to keep the perl syntax -- you don't have to know perl to do so, it's fairly easy to guess in this limited case.

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system install / user setup

(Note: other than getting a public key from the admin's workstation, everything in this mode of install happens on the server).

In this mode, the software is first installed system-wide, then the user runs a command to set up the hosting, supplying a public key.

The root user can install the software system-wide, using either a package (rpm, deb, etc.), or by using the gl-system-install script. (Run the script without any arguments for a brief usage message. If that's not clear enough, read Appendix C below for details.)

A normal user can then set up the hosting by running a command like this:

gl-setup adminname.pub

where adminname.pub is a copy of a public key from that user's workstation.

The first time this is run, it will create a "gitolite-admin" repo and populate it with the right configuration for whoever has the corresponding private key to clone and push it. In other words, that person is the administrator for this particular gitolite instance.

If your system administrator upgrades gitolite itself, things will usually just work without any change; you should not have to do anything special. However, some new features may require additional settings in your ~/.gitolite.rc file.

Finally, in the rare case that you managed to lose your keys to the admin repo and want to supply a new pubkey, you can use this command to replace any such key. Could be useful in an emergency -- just get your new "yourname.pub" to the server and run the same command as above.

IMPORTANT: there are two variables in the ~/.gitolite.rc file: $GL_PACKAGE_CONF and $GL_PACKAGE_HOOKS. If you remove or change either of them, expect trouble :-)

multiple gitolite instances

With this mode of install, it's trivial to create multiple gitolite instances (say one for each department, on some mega company-wide server). You can even do this without giving shell access to the admins. Here's an example with just two "departments", and their admins Alice and Bob:

• create userids webbrowser_repos and webserver_repos
• ask Alice and Bob for their pubkeys; copy them to the respective home directories for convenience
• run su - webbrowser_repos, then gl-setup alice.pub
• (similarly with webserver_repos and bob.pub, and so on for others)

That's it. The URL for all web browser projects is now something like webbrowser_repos@server:reponame, and similarly for the others.

Notice that you only have to do this once for each "department", and it's really just one command after creating the userid. None of these admins need to have a command line on the server, so don't give them the passwords if you don't need to -- the pubkey will allow them to be gitolite admins on their domain, and that's quite enough for normal operations.

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next steps

If you installed it using "gl-easy-install", the last message produced by that script should tell you how to add users, repos, etc. In any case, you will find more details in doc/2-admin.mkd.

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appendix A: server and client requirements for user install

There are 3 machines potentially involved in installing and administering gitolite.

server

This is where gitolite is eventually installed. You need a normal userid (typically "git" but can be anything) on this machine; root access is not needed, but it has to be some sort of Unix (not Windows).

You need the following software on it:

• git
  • can be in a non-PATH location if you are unable to install it normally; see the $GIT_PATH variable in the "rc" file
• perl
  • default install is fine; no special modules are needed
  • (a normal install of git also requires/installs perl, so you probably have it already)
• openssh server
  • (I guess any ssh server that can understand the authorized_keys file format should work)

install workstation

Installing or upgrading the gitolite software itself is best done by running the easy-install program from a gitolite clone.

This script is heavily dependent on bash, so you need a machine with a bash shell. Even the bash that comes with msysgit is fine, if you don't have a Linux box handy.

If you have neither Linux nor Windows+msysgit, you still have a few alternatives:

• use a different userid on the same server (assuming it has bash)
• use the same userid on the same server (same assumption)
• manually simulate the script directly on the server (doable, but tedious)

admin workstation(s)

When you install gitolite, it creates a repository called "gitolite-admin" and gives you permissions on it.

Administering gitolite (adding repos/users, assigning permissions, etc) is done by cloning this repo, making changes to a file called conf/gitolite.conf, adding users' pubkeys to keydir/, and pushing the changes back to the server.

Which means all this can be done from any machine. You'll normally do it from the same machine you used to install gitolite, but it doesn't have to be the same one, as long as your pubkey has been added and permissions given to allow you to push to the gitolite-admin repo.

appendix B: uninstalling gitolite

Sometimes you might find gitolite is overkill -- you have only one user (yourself) pushing maybe. Or maybe gitolite is just not enough -- you want a web-based front end that users can use to manage their keys themselves, etc., in which case you'd probably switch to github, girocco, indefero or gitorious. Gerrit is quite nice too, if you want collaborative code review there's nothing like it. Either way, you'd like to uninstall gitolite.

Uninstalling gitolite is fairly easy, although it is manual. (We'll assume $REPO_BASE in the rc file was left at its default of ~/repositories; if not, adjust accordingly):

server side tasks

• edit ~/.ssh/authorized_keys and delete the # gitolite start and # gitolite end markers and all the lines between them. This will prevent any of your users from attempting a push while you are doing this.

  If you are the only user, and/or need one or more of those keys to continue to access this account (like if one of them is your laptop or your home desktop etc.) then instead of deleting the line you can just delete everything upto but not including the words "ssh-rsa" or "ssh-dss".

• Now remove (or move aside or rename to something else if you're paranoid) the following files and directories.

  ~/.gitolite
  ~/.gitolite.rc
  ~/repositories/gitolite-admin.git
  

• You can remove all of ~/repositories if you have not really started using gitolite properly yet; that's your choice.

  If you do need to preserve the other repos and continue to use them, remove all the update hooks that git installs on each repository. The easiest way is:

  find ~/repositories -wholename "*.git/hooks/update" | xargs rm -f
  

  but you can do it manually if you want to be careful.

client side tasks

• Any remote users that still have access must update their clone's remote URLs (edit .git/config in the repo) to prefix repositories/ before the actual path used, in order for the remote to still work. This is because you'll now be accessing it through plain ssh, which means you have to give it the full path.

• Finally, you as the gitolite admin will probably have a host stanza for "gitolite" in your client's ~/.ssh/config. Find and delete lines that look like this:

  host gitolite
      user git
      hostname your.server
      port 22
      identityfile ~/.ssh/your-gitolite-admin-username
  

appendix C: NOTE TO PACKAGE MAINTAINERS

Here's how you'd package gitolite. In the following description, location "X" can be, say, /usr/share/gitolite/conf or some such, and similarly location "Y" can be perhaps /usr/share/gitolite/hooks. It's upto your distro policies where they are.

Step 1: Clone the gitolite repo and run the make command inside the clone

git clone git://github.com/sitaramc/gitolite.git
cd gitolite
make pu.tar     # or "make master.tar" or "make v1.2.tar" etc

Then you explode the tar file in some temporary location.

Alternatively, you can git checkout the tag or branch you want, and run this command in the clone directly:

git describe --tags --long > conf/VERSION

Step 2: Now make the following changes (no trailing slashes in the location values please):

• src/gl-setup should have the following line:

  GL_PACKAGE_CONF="X"
  

• conf/example.gitolite.rc should have the following lines:

  $GL_PACKAGE_CONF="X";
  $GL_PACKAGE_HOOKS="Y";
  

• delete src/gl-easy-install; that script is meant for a totally different mode of installation and does not play well in this mode :-)

Step 3: Move (or arrange to move) the files to their proper locations as given below:

• everything in "src" goes somewhere on the PATH
• everything in "conf" goes to location "X"
• everything in "hooks" goes to location "Y"

Step 4: There is no step 4. Unless you count telling your users to run gl-setup as a step :)

On the initial install (urpmi, yum install, or apt-get install), you could also choose to setup a userid called "gitolite", and run "gl-setup" as that user; however I do not know how you would come up with the initial pubkey that is needed. Anyway, the point is that the "gitolite" user is no more special than any other in terms of hosting gitolite. Any user can host gitolite on his userid by just running "gl-setup".

When you upgrade, just overwrite all the files; it'll all just work. In fact, other than the initial "gl-setup" run, the only time a gitolite hosting user has to actually do anything is to edit their own ~/.gitolite.rc file if they want to enable or disable specific features.