Confusion with Flask

gistfile1.py

import os
import sys
import json
import time

import requests
from flask import Flask, request

prior_payload = {}

app = Flask(__name__)

@app.route('/', methods=['POST'])
def webhook():
    log(prior_payload.keys())
    log(prior_payload.values())
    # endpoint for processing incoming messaging events
    data = request.get_json() 

    if data["object"] == "page":

        for entry in data["entry"]:
            for messaging_event in entry["messaging"]: #user sent a message

                sender_id = str(messaging_event["sender"]["id"])

#if sender not currently stored in dictionary (prior payload outside of webhook) then set the id as key, and value as 0 until an action has taken place

                if sender_id not in prior_payload.keys():
                    prior_payload[sender_id] = 0

                if messaging_event.get("message"):  # someone sent us a message

                    if "attachments" in messaging_event['message']:
                        sender_id = str(messaging_event["sender"]["id"])       
                        recipient_id = messaging_event["recipient"]["id"]  
                        payload = "uploaded random file"

                        mistake_message(sender_id, payload ,prior_payload[sender_id])

                    elif messaging_event["message"]["text"] == 'done' or messaging_event["message"]["text"] == 'Done':
                        sender_id = str(messaging_event["sender"]["id"])
                        payload = messaging_event["message"]["text"]
                        send_qresponse(sender_id, payload)

                    elif "quick_reply" in messaging_event["message"]:
                        sender_id = str(messaging_event["sender"]["id"])
                        payload = messaging_event["message"]["quick_reply"]['payload']
                        prior_payload[sender_id] = None
                        prior_payload[sender_id] = str(payload)

                        send_qresponse(sender_id, payload)


                    elif messaging_event['message']['text'] == "ready" or messaging_event['message']['text'] == "Ready":
                        sender_id = str(messaging_event["sender"]["id"])
                        payload = messaging_event["message"]["text"]

                        send_qresponse(sender_id, payload)
                        
#This is the conditional for open ended questions. Hence, why it's now using the dictionary as the conditional rather than the json postback from the user (like above). 
#This executes as such - If a message is received (above in the for loop) and the previous action (or payload as it's stored) was read_vacancies then execute code.                        

                    elif prior_payload[sender_id] == "ready_vacancies":
                        sender_id = str(messaging_event["sender"]["id"])
                        prior_payload[sender_id] = "second_question"                                
                        recipient_id = messaging_event["recipient"]["id"]
                        payload = "second_question"
                        send_qresponse(sender_id, payload)


                    elif prior_payload[sender_id] == "second_question":
                        sender_id = str(messaging_event["sender"]["id"])       
                        prior_payload[sender_id] = "third_question"
                        recipient_id = messaging_event["recipient"]["id"]
                        payload = "third_question"
                        send_qresponse(sender_id, payload)

                    elif prior_payload[sender_id] == "third_question":
                        sender_id = str(messaging_event["sender"]["id"])        
                        prior_payload[sender_id] = "fourth_question"
                        recipient_id = messaging_event["recipient"]["id"]
                        payload = "fourth_question"

                        send_qresponse(sender_id, payload)

                    else:
                        sender_id = str(messaging_event["sender"]["id"])       
                        recipient_id = messaging_event["recipient"]["id"]  
                        payload = str(messaging_event["message"]["text"])

                        mistake_message(sender_id, payload)

                if messaging_event.get("delivery"):  
                    pass

                if messaging_event.get("optin"): 
                    pass

                if messaging_event.get("postback"):  

                    sender_id = str(messaging_event["sender"]["id"])
                    recipient_id = messaging_event["recipient"]["id"]
                    payload = str(messaging_event['postback']['payload'])
                    prior_payload[sender_id] = str(payload)

                    send_qresponse(sender_id, payload)

    return "ok", 200

#Example of two of the commands in send_qresponse(sender_id,payload) - one is the standard 'button' responses the other is an open ended question

def send_qresponse(recipient_id,payload):

    if payload == "about_us":
    
#Send post to user with 3 button choices

        log("sending message to {recipient}".format(recipient=recipient_id))

        params = {
                "access_token": os.environ["PAGE_ACCESS_TOKEN"]
        }
        headers = {
            "Content-Type": "application/json"
        }
        data = json.dumps({
            "recipient": {
                "id": recipient_id
            },
            "message": {
                "text":"OK! Let's begin...",
                "quick_replies":[
                    {
                        "content_type":"text",
                        "title":"Philosophy",
                        "payload":"philosophy",
                    },
                    {
                        "content_type":"text",
                        "title":"Team",
                        "payload":"team",
                    },
                    {
                        "content_type":"text",
                        "title":"Location",
                        "payload":"location",
                    }
                ]
            }
        })
        r = requests.post("https://graph.facebook.com/v2.6/me/messages", params=params, headers=headers, data=data)
        if r.status_code != 200:
            log(r.status_code)
            log(r.text)

# send open ended question to user - this is based on the prior_payload variable being X after them typing a general message in response to the question, in the messenger

elif payload == "second_question":

        log("sending message to {recipient}".format(recipient=recipient_id))

        params = {
                "access_token": os.environ["PAGE_ACCESS_TOKEN"]
        }
        headers = {
            "Content-Type": "application/json"
        }
        data = json.dumps({
            "recipient": {
                "id": recipient_id
            },
            "message": {
                "text":"Nice, how many times have you practised that in the mirror? Up next..."
            }
        })
        r = requests.post("https://graph.facebook.com/v2.6/me/messages", params=params, headers=headers, data=data)