How to CloudDeploy an APIFunction that takes audio as input?

Question

I have a function whose argument is Audio and I'd like to deploy it as an API (and then call it from Python). This works as with FormPage[] as follows:

CloudDeploy[
 FormPage[{{"ex", "Upload WAV file:"} -> "UploadedFile"}, 
  AudioPlot@Import[#ex] &]]

But I'm not sure how to set it up with APIFunction[] and then call it as a HTTP GET request. I can assume they are WAV files if that makes it easier.

Answer 1

You can create an APIFunction with a very similar syntax and return e.g. a png"

CloudDeploy[
  APIFunction[
    {{"ex", "Upload WAV file:"} -> Restricted["UploadedFile", "WAV"]}
  , HTTPResponse[ExportString[AudioPlot@Import[#ex, "WAV"], "PNG"]] &
  ]
, "api/audioPlot"
, Permissions -> "Public"
];

Can't say how to call it from Python but from WL it goes like this:

req = HTTPRequest[
  CloudObject["api/audioPlot"]
, <|"Body" -> {"ex" -> File[path/to/file.wav]}|>
];

URLExecute[req, "PNG"]