recurring tasks

There are a few recurring tasks:

• blacken code to enforce formatting consistency
• manually inspect PDFs to verify output; these seem to be the most sensitive aspect of the presentation
• mypy to validate consistency
• sphinx to generate current documentation
• DigitalOcean renewal of $5/month
• Let's Encrypt certificate renewal - 90 days - https://blog.miguelgrinberg.com/post/running-your-flask-application-over-https
• check site for broken links - https://github.com/allofphysicsgraph/proofofconcept/issues/138
• check Google index status - https://github.com/allofphysicsgraph/proofofconcept/issues/159
• validate SSL status - https://www.ssllabs.com/ssltest/analyze.html?d=derivationmap.net&latest

Each of these tasks take time, so including all of them as git commit hooks induces undesirable latency. 

Currently .git/hooks/pre-commit contains

#!/bin/bash

cd v7_pickle_web_interface/flask

docker run --rm -v`pwd`:/scratch --entrypoint='' -w /scratch/ flask_ub make black

I don't want to run mypy and sphinx every time because that would take a lot of my time.

I could run these two every tenth commit.

To get a command to run every tenth commit, I could leverage the date and run a command if the date is modulo 10.

GIT_AUTHOR_DATE='@1589048959 -0400'