[SOLVED] Using jsonify with FlaskRESTful returns me a TypeError

Using jsonify with FlaskRESTful returns me a TypeError

app = Flask(__name_))
api = Api(app)

class MyClass(Resource):
    def post(self):
        # Here i call a function from a separate file, which returns me a big python dict
        result = my_func()
        
        return jsonify(result), 200

This returns me the following error:

TypeError: Object of type Response is not JSON serializable

I tried adding:

test = jsonify(result), 200

And there is not error, so this means the endpoint return throws me an error? I do not understand, does Flask-RESTful call jsonify by default or something?

Solution

You do not have to use jsonify() function, as the framework's core functionality includes automatic JSON serialization for resource methods. This means that when you return a Python object from a POST function, Flask-RESTful will automatically convert it into a JSON-formatted string.

app = Flask(__name_))
api = Api(app)

class MyClass(Resource):
    def post(self):
        # Here i call a function from a separate file, which returns me a big python dict
        result = my_func()
        
        return result, 200