What should the repository contain?

Question

I am trying to set up a Continuous Integration process. For my various build tasks(compiling, testing, documentation etc.)I need to have tools that perform these tasks(csc, NUnit, NDoc etc.). My question is should these tools too go into my source control repository?

Why I think that they should is because I read in some online article that the developer environment should be as much similar to the build server environment. To fulfill this requirement, the article suggested that you put everything that is required for your build in the repository and when you check out the code(or the build server checks out the code) you are ready to build the project right away without first installing any other tools. But on the other hand if I put these tools with my source code in the repository then the build server will have to install them whenever a build is run.

Is it OK to install these tools? Won't it increase the time for each build unnecessarily?

Answer 1

Unless you're customizing the tools there's probably no reason to put their source code in your repository. However there are excellent reasons for putting your config files in the repository.

Answer 2

It's often more trouble than it's worth to try to check in tools to source control. Rather, write a list of software requirements that must be installed before the source can be checked out and built (one thing that would need to be on this list in any case is the source control system itself). If you rely on software being in source control, some tools might need to be installed in certain paths or be otherwise configured (registry entries come to mind).

I would certainly not check in the compiler itself to source control, and I probably wouldn't check in NUnit or NDoc either. Just install these beforehand, as they are not likely to change too much over the lifetime of your project. Your build script might want to check that the expected version(s) of the required software packages are installed before the build may proceed.

Answer 3

Re-installing the tools for every single build is overkill and will slow you down.

However it's by far better to have a server dedicated to the continuous integration so that you know its state ; you sure nobody installed anything that may have an impact on the outcome of the build.

If you want to be able to re-generate today's build next year, you need to be able to re-create your environment first. Make sure you'll be able to re-install your tools (exact same version), either by keeping them on your server (installing the newer versions in different directories), or storing the whole package in your configuration management tool.

Think about how you would create another continuous integration server, either to have two of them, or for a second site, or to recover after a disaster. Document how the continuous integration server was set up.

What really needs to be version controlled, is the build scripts, that access the right versions of the tools, especially if you opt for installing several versions of the tools.