Working with Git and Gerrit » History » Revision 42

Revision 41 (Chris topher, 2011-07-09 11:50) → Revision 42/46 (Michael Voehringer, 2013-12-18 18:22)

h1. Working with Git and Gerrit Code Review 


 The TYPO3 project uses Git and the Gerrit Code Review system to channel commits for review. 

 Here is what you need to know to contribute, more details on Git are available in the "Pro Git book":, book":, the "Gerrit documentation": and other resources (see "helpful links" section below). 

 h2. What <projectname> means in this documentation 

 When we use <projectname> in the following documentation and examples, this means the project name as used in gerrit. If you are unsure you can find out the correct URL to clone from by going to and copy it from the summary page of the project you're interested in. Here are some examples of <projectname>: 


 h2. Quickstart Guides 

 * For a quick "Getting Started" guide, see the [[Gerrit and Git Quickstart]] 
 * Here is a transcript of a session [[Cloning the FLOW3 Base Distribution]] 
 * Here is a transcript of a session [[Cloning the TYPO3 Phoenix Base Distribution]] 

 * If you just want to get the latest sources see: 

 *Note:* Take time to learn and explore git and gerrit! 

 h2. Git 

 * See [[Working with Git]] 

 h2. Gerrit Code Review 

 h3. Registering with gerrit 

 To register with gerrit, you need to have an account on Then visit and log in using your username and password. Click on 'Settings' -> 'Profile', and check that gerrit correctly knows your name and email address (it should; if not it might take a while for the synchronization to take place). 

 In order to be able to upload code, you now need to create a ssh key that gerrit can use to identify you, or tell gerrit about one that already exists. 

 To create a new ssh key, if you don't already have one, run 
 <pre>ssh-keygen -t dsa -f ~/.ssh/id_dsa</pre> 
 The public key for this is now stored in ~/.ssh/ 

 To tell gerrit about your key, log in, and go to 'Settings'. Select 'SSH Keys', and paste your public key into the "Add SSH Public Key" box, or click on the 'Open Key...' option to load it from the filesystem. Click on 'Add' to add the new public key. 

 h3. Setting up ssh config 

 To make things easier, set up ssh so that it knows about the defaults for the gerrit server. Edit @~/.ssh/config@, and add a section like: 
 User <username>  
 IdentityFile ~/.ssh/id_dsa  
 Port 29418</pre> 
 (where <username> is what you logged in with, i.e. your username) 

 To verify your ssh key is working correctly, try using an ssh client to connect to gerrit. You should get the following output if it all works: 
 <pre>$ ssh 
 gerrit: no shell available 
 Connection to closed.</pre> 

 Now you can configure git to push to Gerrit whenever you clone something from All you need to do (for git > 1.6.4) is this 

 <pre>git config --global url."ssh://".pushInsteadOf git://</pre> 

 Now you can clone from git:// and a push on that clone would go into ssh:// using your configure username and port from above. 

 h3. The Change-Id hook 

 Gerrit introduces the concept of "Change IDs". This is a unique reference for a particular change, which remains constant regardless of any changes that are made to the implementation. This allows a single reference to be attached to a given modification, irrespective of any rewrites that may occur as a result of review comments. Manually maintaining change ids is a pain, so gerrit provides a git hook which can be used to automatically add a change id to any new modifications you create. 

 Because hooks cannot be transferred with a clone of a project, you must copy them to your @.git/hooks@ directory and make them executable. The hook can be downloaded from the gerrit server by running the following in the top level of your git tree 
 <pre>scp -p -P 29418 .git/hooks/</pre> 

 *Do this for every working copy you clone!* Make sure the hook is marked as executable after it is installed (scp should take care of this)! 

 When using a superproject with submodules, you can use this to install the hook for every submodule: 
 <pre>git submodule foreach 'scp -p -P 29418 .git/hooks/'</pre> 

 If you cannot use scp (you should, it takes care of permissions automatically!), you can download the hook via HTTP, e.g. using @curl@, @wget@ or a browser, from 

 *Windows users*: If you are using msysgit, the hook and scp work as shown here, simply use the git shell included with msysgit. 

 h3. Different roles for Gerrit 

 The things we did until now described more generally the settings for git and gerrit on your machine. 
 Now we will get in touch with the two main roles you can have in gerrit. 

 * [[Working with Gerrit as a Developer]] 
 * [[Working with Gerrit as a Reviewer]] 

 h2. Helpful links 

 * "Git Homepage": 
 * "Pro Git book": 
 * "Git ready - tutorials": 
 * "Gerrit documentation": 

 h2. Thanks 

 ... to the folks over at "OpenAFS": that made us stumble over gerrit and whose wiki page we shamelessly used as a base for this page. 

 ... to Sebastian Kurf├╝rst, Peter Niederlag, Christopher Hlubek for their help with git, gerrit and redmine. 

 ... Bastian Waidelich for being the brave Windows test user. 

 ... to Shawn Pearce for being helpful on the gerrit mailing list. 

 ... to the TYPO3 Core Team for being open towards a change in SCM flavor.