The Django postgres ORM is synchronous but the GraphQL resolvers are asynchronous. When any ORM commands are attempted to run directly within a resolver, this causes a runtime error You cannot call this from an async context - use a thread or sync_to_async.

I investigated different ways we could potentially use lint or type-check tools or even just a unit test that could catch these errors before they hit prod. Unfortunately I had trouble getting anything that could work reliably, and plug in with our existing tools (ruff, mypy, pytest). I explored the below:

• mypy django-stubs plugin, with enable-async-orm-checks = True - https://github.com/typeddjango/django-stubs - running this plugin pointed at our configurations could not resolve our django settings
• pylint custom plugin (ruff doesn't allow custom plugin) - this required adding support for pylint on top of ruff to get custom plugin functionality - but even trying one out I couldn't get a simple test case to work for our needs
• unit test that traverses resolver functions - this resulted in too many false positives

So in the end I just added in the off-the-shelf async linter offered by flake8 that can catch common errors with async. Unfortunately it doesn't solve the original reason for this investigation re: Django ORM, but can at least be a backstop for other async related pitfalls.

I've also added this "runbook" for on-call or debugging response related to graphQL/async in api

Closes codecov/engineering-team#2473