Flask Testing A Put Request With Custom Headers

Im trying to test a PUT request in my Flask app, using flasks test client. Everything looks good to me but i keep getting 400 BAD request. I tried the same request using POSTMAN

Solution 1:

You do need to actually encode the data to JSON:

import json

with app.test_client() as client:
    api_response = client.put(api, data=json.dumps(data), headers=headers)

Setting data to a dictionary treats that as a regular form request, so each key-value pair would be encoded into application/x-www-form-urlencoded or multipart/form-data content, if you had used either content type. As it is, your data is entirely ignored instead.

Solution 2:

I think it is simpler to just pass the data using the json parameter instead of the data parameter:

reponse = test_client.put(
    api, 
    json=data,
)

Quoting from here:

Passing the json argument in the test client methods sets the request data to the JSON-serialized object and sets the content type to application/json.