Implement proper error handling with Flask.request

[techdev5521]

Flask's request class stores information about the HTTP request being made to the server per request. request.args returns an ImmutableMultiDict which can be accessed like a normal dict.

Example:

# URL: /api/user?uuid=1
request.args["uuid"] 
>>> 1

When the key trying to be accessed doesn't exist, a BadRequestKeyError. This can be resolved many ways, two of which include:

• Trying this access in a try/catch loop, catching the BadRequestKeyError

try:
    if request.args["uuid"]:
       # Do some stuff.
except BadRequestKeyError:
    return {"message": "No UUID was provided."}, 422

• Using the in keyword to test the existence, returning false if the key doesn't exist.

if "uuid" in request.args:
     # Do some stuff.
else:
    return {"message": "No UUID was provided."}, 422

HTTP Code 422

A way forward needs to be agreed upon and the API code needs to be updated for consistency.