Docker Healthchecks

Rationale

Use these to verify the health of database containers. This allows me to only run web services when a database is healthy. This prevents us from hiding a silent failure.

Postgres

healthcheck:
  test: ["CMD", "pg_isready", "-U", "<user>"]
  interval: 30s
  timeout: 20s
  retries: 3    

Valkey

healthcheck:
  test: ["CMD-SHELL", "valkey-cli ping | grep PONG"]
  start_period: 20s
  interval: 30s
  retries: 5
  timeout: 3s