I’ve been working on rebuilding the Java packages in the Ubuntu archive that depend on ‘default-jdk’ against OpenJDK 7 to see where we are likely to have issues if and when we decide to upgrade the default version of Java in Ubuntu to OpenJDK 7
You can see the results here (limited time offer only); and here are the details of how I setup this rebuild.
Setup your rebuild server
So first things first; the current development release of Ubuntu (Oneiric Ocelot) includes the most recent LTS release of Jenkins so installing its pretty easy as long as you are using this release:
sudo apt-get install jenkins
You probably want to configure Jenkins with an administrator email address and point it at a mail relay so that Jenkins can tell you about failures.
Next you need to install a few development tools to make it all hang together nicely:
sudo apt-get install ubuntu-dev-tools sbuild apt-cacher-ng
This should get you to the point where you can setup the jenkins account to use sbuild:
sudo usermod -G sbuild jenkins
sudo stop jenkins
sudo start jenkins
Create sbuild environments
I decided that I wanted to compare current build results with openjdk-6 against the rebuild with openjdk-7 so I created two sbuild environments on my server – one for openjdk-6 and one for openjdk-7:
mk-sbuild --name=oneiric-java-6 oneiric
mk-sbuild --name=oneiric-java-7 oneiric
You might have noticed that I also installed apt-cacher-ng – as alot of the dependencies that get downloaded are the same having a local apt cache makes alot of sense to speed things up; its pretty easy to point the schroots we just created at the local instance of apt-cacher-ng:
sudo su -c "echo 'Acquire::http { Proxy \"http://localhost:3142\"; };' > /var/lib/schroot/chroots/oneiric-java-6-amd64/etc/apt/apt.conf.d/02proxy"
sudo su -c "echo 'Acquire::http { Proxy \"http://localhost:3142\"; };' > /var/lib/schroot/chroots/oneiric-java-7-amd64/etc/apt/apt.conf.d/02proxy"
You will also need to setup some self signed keys to make sbuild work:
sudo sbuild-update -k
So we now have two sbuild environments setup – but we need one to point at openjdk-7 instead of openjdk-6 – I stuck a modified copy of java-common (which determines the default-jdk) in a PPA:
sudo schroot -c oneiric-java-7-amd64-source
apt-get install python-software-properties
add-apt-repository ppa:james-page/default-jdk-7
Obviously this could just as easily be an upgrade to mysql, postgresql or any other package of your choosing.
Setting up Jenkins
I split this rebuild into ‘main’ and ‘universe’ components and used a mutli-configuration project with axis for ‘package’ (containing the list of packages I wanted to rebuild) and ‘version’ (java-6, java-7); I’ve included the config.xml for one of the projects here. You can also see the configuration here.
The build is a very simple script:
#!/bin/bash
export HOME=/var/lib/jenkins
rm -Rf *
pull-lp-source ${package}
sbuild -d oneiric-${version} -A -n ${package}*.dsc
That should do the trick; you can then submit the project for build and it will gradually churn through the packages emailing you with any failures.
JavaCruft 