Playwright in Python Azure Functions

1. Ensure playwright is in requirements.txt.

2. Deploy to Azure Functions v4 consumption plan using remote build (this is the default).

3. The app won't work because chromium is not installed. Add 2 app settings:

   • PLAYWRIGHT_BROWSERS_PATH: /home/site/wwwroot
     • This tells Playwright to install and use chromium from /home/site/wwwroot
   • POST_BUILD_COMMAND: PYTHONPATH=/tmp/zipdeploy/extracted/.python_packages/lib/site-packages /tmp/oryx/platforms/python/3.9.7/bin/python3.9 -m playwright install chromium
     • This is hacky and brittle because the Python version is bound to change. But it works for now. What this does is to run playwright install chromium in the Python version that was used to build the app. It'll install it to /home/site/wwwroot because of the previous app setting.

4. Deploy again, this time the post build command will run and hopefully it works.