How to configure buildbot so that there is one build per push?

Question

Assuming the following git commits in master (we use pull requests, but the below is simpler to reproduce the problem):

$ git clone <my_repo> my_repo
$ cd my_repo
$ git checkout master
$ for delta in 17 34 68; do  # touch & commit a file and then sleep for $delta
   f=$(date +%H%M%S)-$delta  # hhmiss dateformat
   touch $f
   git add $f
   git commit $f -m"timestamped file $f"
   sleep $delta
done
$ git push origin

And there is a builder with a GitPoller with pollInterval=60, usetimestamps=False

This push results in 2 builds being triggered:

• the first build picks up the very first commit
• the second build picks up the other two commits (as the commits are piled up while waiting for the build to complete)

I would like to configure buildbot (0.8.10) so that for one push (or merge request) there is only a single build triggered.

What I've looked so far:

• git+buildbot tagged questions on SO
• http://docs.buildbot.net/0.8.10/manual/cfg-schedulers.html#change-filters - it deals with an individual change, but I specify which commits should trigger one build
• http://docs.buildbot.net/0.8.10/manual/cfg-changesources.html#gitpoller - pollInterval is nice, but with a merge requests, potentially tons of commits come into master in a short time

Answer 1

Use a scheduler that has treeStableTimer set to the time span during which you want the scheduler to wait until the tree is no longer changing. For instance SingleBranchScheduler supports it. It is described as follows:

treeStableTimer

The scheduler will wait for this many seconds before starting the build. If new changes are made during this interval, the timer will be restarted, so really the build will be started after a change and then after this many seconds of inactivity.

If treeStableTimer is None, then a separate build is started immediately for each Change.

I use a SingleBranchScheduler with a 5-minute timer, and it works very nicely. As long as I'm committing, no build is started. If I stop for 5 minutes, then a build starts.

I happen to be using git too but this solution should work with any version control system.