username query param validation

[zhvnibek]

@aidanakenes
In your /profile endpoint you may define the query validation right in the function arguments using Query as in https://fastapi.tiangolo.com/tutorial/query-params-str-validations/#make-it-required. Please have a look at what useful tips this Query class proposes.

Your code may look like this:

@app.get(
    '/profile',
    description='Get profile info'
)
def get(username: str = Query(..., min_length=1, max_length=30, regex='yourregex')):  # ... means required
    # if the username is not valid, it will be rejected (raises fastapi.RequestValidationError) 
    # and will not get to the next line
    parser.get_user(username=username)  # use it directly, because the username is surely valid