First time using Flask: TypeError: _set_response() missing 1 required positional argument: 'self'

Question

This is my first time using Flask so I apologize if this is a simple mistake on my end. I'm trying to create a mock payment processing system that passes form data to Square Checkout API. When running the project I am receiving the following TypeError:

TypeError: _set_response() missing 1 required positional argument: 'self'

Looking up other questions on this subject I saw that I need to instantiate 'self'. How do I do this using Flask?

Here is my code:

from flask import Flask, redirect, url_for, render_template, request
from pprint import pprint
from square.client import Client
from dotenv import load_dotenv
load_dotenv()
import logging
import urllib.parse
import urllib.request
import os
import uuid

app = Flask(__name__)

client = Client(
    access_token = os.getenv("SQUARE_TOKEN"),
    environment = "sandbox"
)

@app.route("/", methods=["POST", "GET"])
def payment():
    return render_template("payment.html")

@app.route("/make-payment", methods=["POST", "GET"])
def _set_response(self):
    self.send_response(200)
    self.end_headers()

def makePayment(self):
    content_length = int(self.headers['Content-Length']) # <--- Gets the size of data
    post_data = self.rfile.read(content_length) # <--- Gets the data itself
    logging.info("POST request,\nPath: %s\nHeaders:\n%s\n\nBody:\n%s\n",
                str(self.path), str(self.headers), post_data.decode('utf-8'))

    #Query and format Python object
    form_query = dict(urllib.parse.parse_qsl(post_data.decode('utf-8')))

    item_name = str(form_query['name'])
    purchase_amount = float(form_query['amount'])
    converted_amount = int(purchase_amount*100)

    result = client.checkout.create_checkout(
        location_id = f"{os.getenv('LOCATION_ID')}",
        body = {
            "idempotency_key": f"{uuid.uuid4()}",
            "order": {
                "order": {
                    "location_id": f"{os.getenv('LOCATION_ID')}",
                    "line_items": [
                        {
                            "name": f"{item_name}",
                            "quantity": "1",
                            "base_price_money": {
                                "amount": converted_amount,
                                "currency": "USD"
                            }
                        }
                    ]
                }
            }
        }
    )

    if result.is_success():
        pprint(result.body)
    elif result.is_error():
        print(result.errors)

    _set_response()


if __name__ == "__main__":
    app.run(host="localhost", port=8000, debug=True)

Traceback:

Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/flask/app.py", line 2095, in __call__
    return self.wsgi_app(environ, start_response)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/flask/app.py", line 2080, in wsgi_app
    response = self.handle_exception(e)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/flask/app.py", line 2077, in wsgi_app
    response = self.full_dispatch_request()
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/flask/app.py", line 1525, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/flask/app.py", line 1523, in full_dispatch_request
    rv = self.dispatch_request()
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/flask/app.py", line 1509, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**req.view_args)
TypeError: _set_response() missing 1 required positional argument: 'self'

Answer 1

The input file is not UTF-8, it is likely some other code page.

Determine what the correct encoding is and alter your program accordingly.