A simple example of a Slack application to go along with work-in-progress blog post at https://lethain.com/creating-reflect-slack-app/
To deploy these files follow the tutorial, update reflect/env.yaml
to include your Slack secrets, and then:
cd reflect
gcloud functions deploy dispatch \
--env-vars-file env.yaml \
--runtime python37 --trigger-http
After which point you're good to go... plus a hundred other steps in the tutorial tho tbh.