There have been a few PDE/Build bug fixes in 3.7 to support building from Git. I recommend using a recent 3.7 build as your base builder. 3.7M5 is due out this week.
General Setup
The Orion releng build is a relatively standard p2 enabled PDE/Build product build.There are a few things that need to be done to get the build working with git:
- Bootstrapping the builder
- Getting map files
- Fetching source from Git
Bootstrapping the Build
The Orion releng builds run via cron job on build.eclipse.org. We need a small shell script that can get the Orion releng project from git and start everything off. We do this using the git archive command:git archive --format=tar --remote=/gitroot/e4/org.eclipse.orion.server.git master releng/org.eclipse.orion.releng | tar -xf -The build machine has local access to the git repository, if we were running from somewhere else, this would change to something like --remote=ssh://user@dev.eclipse.org/gitroot/...
This will get the releng project into the current working directory, at which point we can invoke ant on it.
Getting map files from Git
PDE/Build uses map files to fetch our code from source repositories. The first step to this is getting the map files themselves.PDE/Build comes with default support to fetch map files from CVS which is controlled by a few properties (see Fetch phase Control). This obviously doesn't apply here. However, this step is fully customizable using the customTargets.xml file.
All we need to do is copy the org.eclipse.pde.build/templates/headless-build/customTargets.xml file into our builder and modify the getMapFiles target. We can then use the git archive command to get our map files. It would look something like this:
<target name="getMapFiles" unless="skipMaps">
<mkdir dir="${buildDirectory}/maps" />
<exec executable="git" dir="${buildDirectory}/maps"
output="${buildDirectory}/maps/maps.tar">
<arg line="archive -format=tar" />
<arg line="--remote=/gitroot/e4/org.eclipse.orion.server.git" />
<arg line="master releng/org.eclipse.orion.releng/maps" />
</exec>
<untar src="${buildDirectory}/maps/maps.tar" dest="${buildDirectory}/maps" />
</target>
Because the "| tar -xf -" we used earlier is a redirection done by the shell, that doesn't work when we invoke git from ant. Here we specify a file to hold the output of the archive command, this ends up being a tar file which we can just untar.Fetching source from Git
PDE/Build has an extension point where fetch script generators for different repositories can be plugged in. The EGit project provides an implementation for this extension point.The org.eclipse.egit.fetchfactory bundle is available from the http://download.eclipse.org/egit/pde/updates-nightly p2 repository. Install that bundle into the eclipse install that is used to run your build.
Git Map Files
Once we have the egit fetchfactory, all we need to do is update our map files with entries for GIT. Here is an example map file entry from Orion:plugin@org.eclipse.orion.client.core=GIT,tag=v20110125-1800,\
repo=dev.eclipse.org:/gitroot/e4/org.eclipse.orion.client.git,\
path=bundles/org.eclipse.orion.client.core
- tag is the tag to use when fetching the bundle from git
- repo is the path to the git repository. In order to omit the user from the repository path, the build needs to run as a user who has ssh access to the git repo at dev.eclipse.org
- path is the path within the git repository to the project we are interested in.
Final Details
- The EGit fetch factory works by cloning the git repository to a local directory, checking out the tag and then copying the project over to the build Directory. Builders can set the fetchCacheLocation property to specify a local directory where the git clones can be kept. This location may be reused from build to build to avoid having to re-download the entire repository each build.
- "Nightly" builds are set up to build the latest code from HEAD. For CVS, this is usually accomplished by setting "fetchTag=HEAD" to override the map file entries. For Git you would use "fetchTag=origin/master". If you are using both CVS and GIT you can set both with "fetchTag=CVS=HEAD,GIT=origin/master".
- The Eclipse Platform team uses the releng tool plugin to manage their map files in CVS, there is not yet an equivalent tool for git. See the Orion Releng and E4/Git wiki pages for instruction on how to manage map files.
