How to Compile Unity from Source

These instructions will help you build unity from source. However, there are a
few things to consider:

• I recommend that you never copy anything you've built locally outside your home directory. Doing so is asking for trouble, especially as we're building the entire desktop shell. If you manage to ruin your system-wide desktop shell you'll be a very sad programmer!
• I'm assuming that you're running the precise Ubuntu release (still in alpha at the time of writing, but very usable).
• I'm also assuming that you want to build unity from trunk (that is, lp:unity).

Without further ado, let's get to it:

Getting the source code

If you don't already have Bazaar installed, install it now:

sudo apt-get install bzr

You may want to make yourself a folder for the unity code. I tend to do something like this:

mkdir -p ~/code/unity
cd ~/code/unity

Let's grab the code from launchpad:

bzr branch lp:unity trunk

This may take a while. If you prefer to use Bazaar checkouts instead of branches, that's fine to.

Installing Build Dependancies

We need to get the build-dependancies for unity. Thankfully, apt-get makes this trivial:

sudo apt-get build-dep unity

Compiling Unity

I have a set of bash functions that makes this step significantly easier. To use them, copy the following bash code into a file in your home directory called ".bash_functions":

function recreate-build-dir()
{
   rm -r build
   mkdir build
   cd build
}

function remake-autogen-project()
{
    ./autogen.sh --prefix=/home/thomi/staging --enable-debug
    make clean && make && make install
}

function remake-unity()
{
    recreate-build-dir
    cmake .. -DCMAKE_BUILD_TYPE=Debug -DCOMPIZ_PLUGIN_INSTALL_TYPE=local -DCMAKE_INSTALL_PREFIX=/home/thomi/staging/ -DGSETTINGS_LOCALINSTALL=ON
    make  && make install
}

function unity-env
{
 export PATH=~/staging/bin:$PATH
 export XDG_DATA_DIRS=~/.config/compiz-1/gsettings/schemas:~/staging/share:/usr/share:/usr/local/share
 export LD_LIBRARY_PATH=~/staging/lib:${LD_LIBRARY_PATH}
 export LD_RUN_PATH=~/staging/lib:${LD_RUN_PATH}
 export PKG_CONFIG_PATH=~/staging/lib/pkgconfig:${PKG_CONFIG_PATH}
 export PYTHONPATH=~/staging/lib/python2.7/site-packages:$PYTHONPATH
}

Note: You will need to replace all instances of "/home/thomi" with your own home directory path!

Now run this in a terminal:

echo ". ~/.bash_functions" >> ~/.bashrc

This ensures that the next time you open a bash shell the functions listed above will be available to you. To avoid having to close and re-open a terminal, we can read them manually just this once:

. ~/.bash_functions

You should now be able to run:

remake-unity

from the trunk/ directory we created earlier. That's it - you're building unity!

Not so Fast!

Chances are, while trying to build unity, you found that it needed a newer version of one of the several supporting projects than you had installed. At the time of writing, you can't compile unity without first building nux from sources first. Thankfully, that's pretty easy with the use of the functions you now have set up.
First we get the source code:

mkdir -p ~/code/nux
cd ~/code/nux
bzr branch lp:nux trunk
cd trunk

Then we need to get the build dependencies for nux.

sudo apt-get build-dep nux

Unfortunately there are a fewpackages missing, so you'll want to install them as well:

sudo apt-get install gnome-common libibus-1.0-dev libgtest-dev google-mock libxtst-dev

Then we use the functions above to build nux:

remake-autogen-project

That's it! You can then go back and build unity - hopefully this time with better success.

Build Notes

You may have noticed that the remake-* scripts do a complete rebuild every time. If you'd prefer to just build the files that have changed since last time, change to the trunk/build/ directory, and run:

make && make install

Running Unity

If you'd like to run the version of unity you've built, rather than the system-wide version, open a terminal and run the following commands:

unity-env
unity --replace &

The first line patches several environment variables such that unity will subsequently be launched from your local staging directory. These environment variables will remain changed until you close the terminal, so you need only run unity-env once.

Introducing: indicator-jenkins

For my day job I've been monitoring a jenkins instance (specifically, the public Ubuntu QA jenkins instance) using my web browser. This is obviously suboptimal - I'd like to be able to see the state of the jenkins jobs I'm interested at a glance, without having to open my web browser.

I couldn't find a solution to my problem, so I created one: indicator-jenkins is a panel indicator for your desktop manager of choice. It allows you to select one or more jobs from a jenkins server, and follow the job state without having to open your browser.

The project is hosted on launchpad, and is built daily into my PPA. To install it (I'm assuming you're running Ubuntu):

$ sudo add-apt-repository ppa:thomir/indicator-jenkins

$ sudo apt-get update

$ sudo apt-get install indicator-jenkins

Once it's installed you can launch it in a couple of different ways:

• From a terminal - jut run indicator-jenkins. If you run it on the terminal you'll get a lot of debugging output (useful if you want to submit a patch, or figure out why it's not working).
• From the unity dash - open the dash, and search for 'jenkins' - it's probably going to be the first link.
  
  

Once it's running you should see the jenkins icon in your panel. To set it up, click the icon to open the settings dialog, enter the URL of the jenkins instance you want to look at, hit the refresh button, and pick the job(s) you want to monitor. Click OK and you're done! It's simpler than it sounds - see for yourself:

Right now it's pretty rough-and-ready - there are many features I'd like to add:

• Integrate desktop notifications, so you can be alerted when a job state changes.
• Customise panel icon based on job state (i.e.- show a red icon if any of the monitored jobs are failing).
• Allow user to customise refresh period.
• Allow user to monitor jobs from more than one jenkins server.
• Show more information about a jenkins job. For a start, show stability as well as current status, and maybe in the future show unity test pass/failure rates for projects that have that information.

How it's Made:

The entire application is written in python. We make use of several python modules:

• The python-appindicator package gives us the ability to create an icon on the menu, and the python gtk2 bindings are used to create the menu and settings dialog.
• The python 'multiprocessing' module is used to spin up worker processes to fetch the data from jenkins. Initially the application used threads for this, but python's threading support isn't great, and it was taking too long. 
• The python 'json' module is used to save and load settings.
• The python-jenkins package is used to communicate with the jenkins server.

This is a great example of python's "batteries included" approach to programming. All you have to do is provide the glue between already-existing python modules.