Routing

For the REST API, we use Flask as a library.

Info

This part of the documentation further outlines the technical details about REST APIs and less about the project itself. Read this part if you want to learn more about adding your own endpoints. For the existing endpoints, please check out the endpoint documentation.

Routing in Python

Routes in Flask generally consist of a decorator and a method. You need to have initialized a Flask app first in order to set up routes.

Routing Example

app = Flask('Your app name')

@app.route('your/endpoint', methods=['GET'])
def endpoint():
    return ({'message': 'Hi'}, 200)

The RestMaybe helper

When handling REST Calls, you may often wanna check first if the requests are any good at all. Here, we have developed a helpful tool called RestMaybe. Using RestMaybe, we can chain calls in a way to internally build some Request Object and pass it into a function. In the function you want to pass, you should return a valid Flask response like you would in a normal Flask endpoint function.

RestMaybe Example

app = Flask('Math Solver')

@app.route('binary-op', methods=['POST'])
def binary_op():
    return RestMaybe(request) \
            .wellformed() \
            .exists('operand1') \
            .exists('operand2') \
            .optional('operator') \
            .run(lambda request, object: _binary_op(object))

def _binary_op(request):
    operand1 = request['operand1']
    operand2 = request['operand2']
    operator = request.get('operator', 'plus')
    # ...

    return ({'result': result, 'message': 'That was quite difficult.'}, 200)

RestMaybe

RestMaybe is a class that should make checking if the request is valid easier.

Currently, the capabilities of RestMaybe are limited to checking if a given request is a Json and if a given request has valid keys.

__init__(request)

Passes initial Request to the RestMaybe.

Parameters:

Name	Type	Description	Default
request	Request	The sent HTTP Request to handle.	required

exists(key)

Checks if a given key exists in the request Json. Modifies the error variable, if not.

Warning

This function will not check if the request was a Json in the first place. Use wellformed first.

Parameters:

Name	Type	Description	Default
key	str	The key to check for if it is in the request.	required

Returns:

Name	Type	Description
self	Self	Itself to chain the next call.

optional(key)

Collects an optional key. Will not throw an error if the key isn't passed.

Warning

This function will not check if the request was a Json in the first place. Use wellformed first.

Parameters:

Name	Type	Description	Default
key	str	The key to check for if it is in the request.	required

Returns:

Name	Type	Description
self	Self	Itself to chain the next call.

run(function)

If every check made was true, this function will call another function that the user can pass. If not, the error will be returned directly.

Parameters:

Name	Type	Description	Default
function	Callable[[Request, Any], Any]	The function f : Request -> Json -> Response, which takes in the request and the value for every key checked before and gives out any response at will.	required

Returns:

Name	Type	Description
response		A valid Flask Response.

wellformed()

Checks if the HTTP Request is a Json. Modifies the error variable, if not.

Returns:

Name	Type	Description
self	Self	Itself to chain the next call.