BuildBot: build/test automation http://buildbot.sourceforge.net/ Brian Warner Abstract: The BuildBot is a system to automate the compile/test cycle required by most software projects to validate code changes. By automatically rebuilding and testing the tree each time something has changed, build problems are pinpointed quickly, before other developers are inconvenienced by the failure. The guilty developer can be identified and harassed without human intervention. By running the builds on a variety of platforms, developers who do not have the facilities to test their changes everywhere before checkin will at least know shortly afterwards whether they have broken the build or not. Warning counts, lint checks, image size, compile time, and other build parameters can be tracked over time, are more visible, and are therefore easier to improve. The overall goal is to reduce tree breakage and provide a platform to run tests or code-quality checks that are too annoying or pedantic for any human to waste their time with. Developers get immediate (and potentially public) feedback about their changes, encouraging them to be more careful about testing before checkin. Features: * run builds on a variety of slave platforms * arbitrary build process: handles projects using C, Python, whatever * minimal host requirements: python and Twisted * slaves can be behind a firewall if they can still do checkout * status delivery through web page, email, IRC, other protocols * track builds in progress, provide estimated completion time * flexible configuration by subclassing generic build process classes * debug tools to force a new build, submit fake Changes, query slave status * released under the GPL DOCUMENTATION: The PyCon paper has a good description of the overall architecture. It is available in HTML form in docs/PyCon-2003/buildbot.html, or on the web page. The User's Manual is in docs/buildbot.info, and the Installation chapter is the best guide to use for setup instructions. The .texinfo source can also be turned into printed documentation. An HTML representation is available on the Buildbot home page. REQUIREMENTS: Python: http://www.python.org Buildbot requires python-2.3 or later, and is primarily developed against python-2.4 . It has *not* yet been tested against python-2.5 . Twisted: http://twistedmatrix.com Both the buildmaster and the buildslaves require Twisted-2.0.x or later. As always, the most recent version is recommended. It has been tested against Twisted-2.4.0 and Twisted SVN as of the date of release. Twisted is delivered as a collection of subpackages. You'll need at least "Twisted" (the core package), and you'll also want TwistedMail, TwistedWeb, and TwistedWords (for sending email, serving a web status page, and delivering build status via IRC, respectively). You might also want TwistedConch (for the encrypted Manhole debug port). Note that Twisted requires ZopeInterface to be installed as well. ACCESSORIES: CVSToys: http://purl.net/net/CVSToys If your buildmaster uses FreshCVSSource to receive change notification from a cvstoys daemon, it will require CVSToys be installed (tested with CVSToys-1.0.10). If the it doesn't use that source (i.e. if you only use a mail-parsing change source, or the SVN notification script), you will not need CVSToys. INSTALLATION: Please read the User's Manual in docs/buildbot.info or docs/buildbot.html for complete instructions. This file only contains a brief summary. RUNNING THE UNIT TESTS If you would like to run the unit test suite, use a command like this: PYTHONPATH=. trial buildbot.test This should run up to 221 tests, depending upon what VC tools you have installed. On my desktop machine it takes about six minutes to complete. Nothing should fail (at least under unix), a few might be skipped. If any of the tests fail, you should stop and investigate the cause before continuing the installation process, as it will probably be easier to track down the bug early. There are a few known failures under windows and OS-X, but please report these to the mailing list so we can isolate and resolve them. Neither CVS nor SVN support file based repositories on network filesystem (or network drives in Windows parlance). Therefore it is recommended to run all unit tests on local hard disks. INSTALLING THE LIBRARIES: The first step is to install the python libraries. This package uses the standard 'distutils' module, so installing them is usually a matter of doing something like: python ./setup.py install To test this, shift to a different directory (like /tmp), and run: buildbot --version If it announces the versions of Buildbot and Twisted, the install went ok. SETTING UP A BUILD SLAVE: If you want to run a build slave, you need to obtain the following pieces of information from the administrator of the buildmaster you intend to connect to: your buildslave's name the password assigned to your buildslave the hostname and port number of the buildmaster, i.e. example.com:8007 You also need to pick a working directory for the buildslave. All commands will be run inside this directory. Now run the 'buildbot' command as follows: buildbot create-slave WORKDIR MASTERHOST:PORT SLAVENAME PASSWORD This will create a file called "buildbot.tac", which bundles up all the state needed by the build slave application. Twisted has a tool called "twistd" which knows how to load these saved applications and start running them. twistd takes care of logging and daemonization (running the program in the background). /usr/bin/buildbot is a front end which runs twistd for you. Once you've set up the directory with the .tac file, you start it running like this: buildbot start WORKDIR This will start the build slave in the background and finish, so you don't need to put it in the background yourself with "&". The process ID of the background task is written to a file called "twistd.pid", and all output from the program is written to a log file named "twistd.log". Look in twistd.log to make sure the buildslave has started. To shut down the build slave, use: buildbot stop WORKDIR RUNNING BEHIND A NAT BOX: Some network environments will not properly maintain a TCP connection that appears to be idle. NAT boxes which do some form of connection tracking may drop the port mapping if it looks like the TCP session has been idle for too long. The buildslave attempts to turn on TCP "keepalives" (supported by Twisted 1.0.6 and later), and if these cannot be activated, it uses application level keepalives (which send a dummy message to the build master on a periodic basis). The TCP keepalive is typically sent at intervals of about 2 hours, and is configurable through the kernel. The application-level keepalive defaults to running once every 10 minutes. To manually turn on application-level keepalives, or to set them to use some other interval, add "--keepalive NNN" to the 'buildbot slave' command line. NNN is the number of seconds between keepalives. Use as large a value as your NAT box allows to reduce the amount of unnecessary traffic on the wire. 600 seconds (10 minutes) is a reasonable value. SETTING UP A BUILD MASTER: Please read the user's manual for instructions. The short form is that you use 'buildbot create-master MASTERDIR' to create the base directory, then you edit the 'master.cfg' file to configure the buildmaster. Once this is ready, you use 'buildbot START MASTERDIR' to launch it. A sample configuration file will be created for you in WORKDIR/master.cfg . There are more examples in docs/examples/, and plenty of documentation in the user's manual. Everything is controlled by the config file. SUPPORT: Please send questions, bugs, patches, etc, to the buildbot-devel mailing list reachable through http://buildbot.sourceforge.net/, so that everyone can see them.