How do I pass args and kwargs to a REST endpoint built with FastAPI?

I am building a REST api using FastAPI. The goal is to run a python function over the network and return the result.

Note that I CAN modify the client & the server code.

At a high level the code is:

@app.post('/my_endpoint')
def serve_data(q:dict):
    return foo(*q.get('args', []), **q.get('kwargs', {}))

Where foo is some complex Python function that takes a very large amount of args & kwargs.

And on the client side I am using:

def get_data(endpoint:str='my_endpoint', args:list=None, kwargs:dict=None)->pd.DataFrame:
    
    q = dict(
        args = args if args else [], 
        kwargs = kwargs if kwargs else {}
    )
    
    qj = json.dumps(q)
    
    
    response = requests.post(url = f'http://my_url/{endpoint}', data=qj)
    data = response.json()
 
    df = pd.read_json(data)
        
    return df

The code works, but I don’t like having to call get_data using explicit args and kwargs.

eg.

get_data(args=['A', 19, 99], kwargs={'date': '2021-01-01', 'font_size': 2})

I’d like to be able to “pass” the args and kwargs into get_data all the way down to foo.

The code above would become:

get_data('A', 19, 99, date='2021-01-01', font_size=2)

# ie. the same signature as `foo`
# On the server this is run:
# foo('A', 19, 99, date='2021-01-01', font_size=2)

Any ideas?

Answers:

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Method 1

You can simply define your function like this:

def get_data(endpoint:str='my_endpoint', *args, **kwargs)->pd.DataFrame:
    q = dict(
        args = list(args) if args else [], 
        kwargs = kwargs if kwargs else {}
    )
    ...

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