Project: The Release Checklist in Python

Before a new version goes live, a release checklist makes sure nothing was forgotten on the server. Your function release_checklist(env, db, client) gets the server's environment variables as a dictionary, its database, and a test client of its app. It collects what is wrong in a list, problems, and the code at the end prints it.

Each check reads a value, compares it, and appends a sentence when something is wrong. Here is a check for another setting:

env = {"SHOP_NAME": "Mug Shop", "ADMIN_EMAIL": ""}
problems = []
if env.get("ADMIN_EMAIL", "") == "":
    problems.append("set ADMIN_EMAIL")
print(problems)   # ['set ADMIN_EMAIL']

Your checklist asks four things, in this order. Debug mode is off: FLASK_DEBUG is "0", or not set at all. Every name in SECRETS is set and not empty. Every name in MIGRATIONS has its row in the table migrations: fetchone() gives None when it doesn't. And GET /health answers 200.

Six test servers go through the checklist. The finished code prints:

Server 1: all set
Ready to release
Server 2: debug left on
To do: turn debug off (FLASK_DEBUG is 1)
Server 3: secrets forgotten
To do: set the secret SECRET_KEY
To do: set the secret WEBHOOK_SECRET
Server 4: new code, old database
To do: run the migration 003_add_reviews
Server 5: the app is not healthy
To do: fix /health, it answers 503
Server 6: nothing done yet
To do: turn debug off (FLASK_DEBUG is true)
To do: set the secret SECRET_KEY
To do: set the secret PAYMENTS_API_KEY
To do: set the secret WEBHOOK_SECRET
To do: run the migration 001_create_products
To do: run the migration 002_create_orders
To do: run the migration 003_add_reviews
To do: fix /health, it answers 503

Your task: inside release_checklist, add the four checks: debug, then the secrets, then the migrations, then /health. Each one appends the sentence that follows To do: in the output above.

Assignment
Follow the Coding Tutorial to add the four checks of the release checklist: debug off, secrets set, migrations run and /health green.

Hint
env.get with a default never raises. Look up each migration with a ? placeholder and the tuple (name,). Turn the status code into text with str before adding it to a sentence.