GitHub Pull Request Builder

What is it?

The script will:

• query for any open pull requests (PRs) of a repository on GitHub
• checkout the code
• run tests via a specified shell script
• update status of the PR.

That's it!

It will keep a record of all PRs that are being looked at or have already been looked at, and ignore these on next run.

To make it run continuously, use something like crontab, or maybe just tmux with a while sleep loop? That's CI for ya right there :-)

How do I use it?

First install jq with brew, apt-get etc.

The syntax for running the script is:

$ ./pr-builder.sh <github-user> <personal access token> <repo> <base-branch> <log-base-url> <context> <test-script>

Example:

$ ./pr-builder.sh grav abc123beefbeefbeef grav/my-repo master http://example.com/logs my-ci ./test.sh

This will test any open PR that is destined for the master branch.

The context parameter is part of the naming of the eventual status check that will be recorded on Github. If, for instance, you set the context parameter to my-ci and the base to master, a status check called my-ci master will eventually show up for the processed pull requests. You can then use Github's branch protection rules to make a status check required.

To read more about status checks, visit this page: https://help.github.com/articles/about-status-checks/

Make sure the PR-branch contains a test.sh script in the root (or whatever you've defined).

To generate a personal access token, visit this page: https://github.com/settings/tokens

Can I see the logs?

This is where the log-base-url parameter comes in.

The logs of each test run are named <commit-sha>_<base>.txt and placed in the db folder.

If, for instance, you specify http://example.com:8000 as log-base-url, and a commit with sha abc123 is processed, the Github pull-request page will show a link to http://example.com:8000/abc123_master.txt.

This way, you should be able to just point your webserver to the db directory on your server in order to expose all the logs. Eg with the twistd webserver (https://twistedmatrix.com/trac/wiki/TwistedWeb):

$ cd /path/to/pr-builder/db
$ twistd -n web -p 8000 --path .

But ... I want it to do deployment

Well, you're in luck. If you set the magic env-var LATEST_COMMIT to something, pr-builder will process the lastest commit of the specified branch. So, for example:

$ LATEST_COMMIT=1 ./pr-builder grav abc123beefbeefbeef grav/my-repo master http://example.com/logs my-deploy ./launch-missiles.sh

Again, if you wrap it in a while loop, you now have continuous deployment.

Can I please have triggers via github-comments?

Well ok ... there's a crude copy/paste of the main script in this repo, called comment-command.sh which does just this. Eventually, I'll refactor the two scripts into one and document it.

TODO

• describe deployment feature
• refactor comment-command.sh into main script and document it
• handle fatal: reference is not a tree: <sha> - seems to come up if PR has arrived to GitHub before commit
• specify license
• specify timeout of some sort
• move config into a file