POST input to a Serverless Function

Hello all. Following the documentation on Serverless Functions, it is demonstrated how to pass over input arguments into the function handler (the ‘args’ for the ‘main()’ function. It is shown and explained that the parameters can be passed as query strings (i.e. GET method) and retrieved in the handler using the ‘args’ object. Is there a way to also pass such input parameters using POST? For instance, listening to PayPal webhook require POST acceptance. Also, passing over a large base64 input (image/audio) does not make sense as a GET parameter. How can these be accepted and retrieved within the main(args) handler, both for a web function as well as internal call. Thanks!