[FEAT] Handling client errors

[jmensch1]

Overview

When the frontend hits the api with invalid parameters, like a missing startDate or a string where an integer is expected, the backend responds in one of two ways:

• a 500 error, with a generic message like "The server encountered an internal error and cannot complete your request." This doesn't help the frontend figure out what went wrong.
• a 200 response that contains an error message in the JSON (like {"Error": "a start date is required"}). In this case, the message is helpful but the frontend's api infrastructure (axios/redux saga) doesn't know that the response is an error because it has a status code of 200.

Action Items

• Return 400 errors with helpful messages whenever the frontend submits invalid params to the api.

Resources/Instructions

https://sanic.readthedocs.io/en/latest/sanic/exceptions.html