Developing locally

Here are some steps to develop this dependency locally and interact with source, interpreted from https://confluence.twitter.biz/display/ENG/Overview%3A+Python+3rdparty+in+Source

Create a git branch for this change.
Edit airflow/version.py to change the version.
Edit source/3rdparty/python/BUILD with the corresponding version.
Run the command python3.7 setup.py bdist_wheel in the airflow directory to build the wheel. It will be written to airflow/dist.
Clean out the pex cache: rm -rf ~/.pex ~/.cache/pants.
Run ps aux | grep pantsd to find the pid of the pantsd process.
Run kill $pid where $pid is the the pid just observed.
From the source directory, run ./pants clean-all.
Now here are the hacky parts. The run-local.sh and run-aurora.sh all run pants commands without the option --python-repos-repos. You can either edit these to include this option, or run a pants command that includes it, which will cache the local artifact you need, e.g. ./pants test airflow:: --python-repos-repos="['file:///path/to/airflow/dist/', 'https://science-binaries.local.twitter.com/home/third_party/source/python/wheels/', 'https://science-binaries.local.twitter.com/home/third_party/source/python/bootstrap/','https://science-binaries.local.twitter.com/home/third_party/source/python/sources/']"
Now you can start up airflow instances as usual with the newly built wheel!
See the above link for Adding Dependencies to science-libraries.

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