Best Practices for Build and Release Management Part 2
Ok, as promised in Part 1, I’ll go into a bit more detail about each of the areas outlined previously, starting with…
The Build Process
This area, perhaps more than any other area I’ll be covering in this section, has benefited most from the introduction of some ultra handy tools. Back in the day, building/compiling software was fairly manual, and could only be automated to a certain degree, make files and batch systems were about as good as it got, and even that relied on a LOT of planning and could quite often be a nightmare to manage.
These days though, the build phase is exceedingly well catered for and is now a very simple process, and what’s more, we can now get an awful lot more value out of this single area.
As I mentioned before, one of the aims of release management is to make software builds simple, quick and reliable. Tools such as Ant, Nant (.Net version of Ant), Maven, Rake and MSBuild help us on our path towards our goal in many ways. Ant, MSBuild and Nant are very simple XML based scripting languages which offer a wide ranging level of control – for instance, you can build entire solutions with a single line of script, or you can individually compile each project and specify each dependency – it’s up to you to decide what level of control you need. I believe that build scripts should be kept simple and easy to manage, so when dealing with NAnt and MSBuild for .Net solutions I like to build each project by calling an .proj file rather than specifically compiling each library. The .proj files should be constructed correctly and stored in source control. Each build should get the latest proj file (and the rest of the code, including shared libraries – more on that later) and compile the project.
For Java projects. Ant and Maven are the most popular tools. Ant, like Nant, gives the user a great deal of control, while Maven has less inherent flexibility and enforces users to adhere to its processes. However, both are equally good at helping us make our build simple, quick and reliable. Maven uses POM files to control how projects are built. Within these POM files a build engineer will define all the goals needed to compile the project. This might sound a little tedious but the situation is made easier by the fact that POM files can inherit from master/parent POM files, reducing the amount of repetition and keeping your project build files smaller, cleaner and easier to manage. I would always recommend storing as much as possible in parent POM files, and as little as you can get away with in the project POMs.
One of the great improvements in software building in recent years has been the introduction of Continuous Integration. The most popular CI tools around are CruiseControl, CruiseControl.Net, Hudson and Bamboo. In their simplest forms, CI tools are basically just schedulers, and they essentially just kick off your build tools. However, that’s just the tip of the iceberg, because these tools can do much, MUCH more than that – I’ll explain more later, but for now I’ll just say that they allow us to do our builds automatically, without the need for any human intervention. CI tools make it very easy for us to setup listeners to poll our source code repositories for any changes, and then automatically kick off a build, and then send us an email to let us know how the build went. It’s very simple stuff indeed.
So let’s take a look at what we’ve done with our build process so far:
- We’ve moved away from manually building projects and started using simple build scripts, making the build process less onerous and not so open to human error. Reliability is on the up!
- We’ve made our build scripts as simple as possible – no more 1000 line batch files for us! Our troubleshooting time has been significantly reduced.
- We’ve moved away from using development UIs to make our builds – our builds are now more streamlined and faster.
- We’ve introduced a Continuous Integration system to trigger our builds whenever a piece of code is committed – our builds are now automated.
So in summary, we’ve implemented some really simple steps and already our first goal is achieved – we’ve now got simple, quick and reliable builds. Time for a cup of tea!