feat: add blockchain listener to remind the client

backend/blockchain_listener.py

@@ -0,0 +1,119 @@
+from web3 import Web3
+from bot import BankBot
+
+SBT_ADDRESS = ''
+ABI = [
+        {
+          "anonymous": False,
+          "inputs": [
+            {
+              "indexed": True,
+              "internalType": "address",
+              "name": "client",
+              "type": "address"
+            },
+            {
+              "indexed": True,
+              "internalType": "address",
+              "name": "bank",
+              "type": "address"
+            },
+            {
+              "indexed": False,
+              "internalType": "uint256",
+              "name": "id",
+              "type": "uint256"
+            },
+            {
+              "indexed": False,
+              "internalType": "uint256",
+              "name": "amount",
+              "type": "uint256"
+            }
+          ],
+          "name": "Repay",
+          "type": "event"
+        },
+        {
+          "anonymous": False,
+          "inputs": [
+            {
+              "indexed": True,
+              "internalType": "address",
+              "name": "client",
+              "type": "address"
+            },
+            {
+              "indexed": True,
+              "internalType": "address",
+              "name": "shop",
+              "type": "address"
+            },
+            {
+              "indexed": True,
+              "internalType": "address",
+              "name": "bank",
+              "type": "address"
+            },
+            {
+              "indexed": False,
+              "internalType": "uint256",
+              "name": "id",
+              "type": "uint256"
+            },
+            {
+              "indexed": False,
+              "internalType": "uint256",
+              "name": "amount",
+              "type": "uint256"
+            }
+          ],
+          "name": "Borrow",
+          "type": "event"
+        }
+    ]
+
+class Listener():
+    def __init__(self, bot: BankBot) -> None:
+        self.w3 = Web3(Web3.HTTPProvider('http://127.0.0.1:7545'))
+        self.contract = self.w3.eth.contract(address=SBT_ADDRESS, abi=ABI)
+        self.bot = bot
+
+    def handle_repay_event(self, event):
+        print("Repay Event received:")
+        print(event['args'])
+        print("---")
+
+        args = event['args']
+        if args['client'] in self.bot.clients:
+            chat_id = self.bot.clients[args['client']]
+            self.bot.updater.bot.send_message(chat_id=chat_id, text="已經收到您編號 #{} 的帳款，共 {} ETH.".format(
+                args['id'], int(args['amount'])/(10**18)
+            ))
+
+    def handle_borrow_event(self, event):
+        print("Borrow Event received:")
+        print(event['args'])
+        print("---")
+
+        args = event['args']
+        if args['client'] in self.bot.clients:
+            chat_id = self.bot.clients[args['client']]
+            self.bot.updater.bot.send_message(chat_id=chat_id, text="您已經透過本銀行向 {} 支付 {} ETH. 帳款編號(#{})".format(
+                args['shop'], int(args['amount'])/(10**18), args['id']
+            ))
+        
+        if args['shop'] in self.bot.clients:
+            chat_id = self.bot.clients[args['shop']]
+            self.bot.updater.bot.send_message(chat_id=chat_id, text="本銀行已經先替客戶 {} 向您支付 {} ETH. 帳款編號(#{})".format(
+                args['client'], int(args['amount'])/(10**18), args['id']
+            ))
+
+    def start(self):
+        borrow_event_filter = self.contract.events.Borrow.create_filter(fromBlock='latest')
+        repay_event_filter = self.contract.events.Repay.create_filter(fromBlock='latest')
+        while True:
+            for event in borrow_event_filter.get_new_entries():
+                self.handle_borrow_event(event)
+            for event in repay_event_filter.get_new_entries():
+                self.handle_repay_event(event)

backend/bot.py

@@ -1,8 +1,12 @@
+'''
+    python-telegram-bot: 13.7, version 20.XX cannot work
+'''
+
 from urllib import response
 from cairo import Filter
 from telegram import Update
 import torch
-from telegram.ext import MessageHandler, CallbackContext, CommandHandler, filters, Application
+from telegram.ext import MessageHandler, CallbackContext, CommandHandler, Filters, Updater
 import json
 import os
 
@@ -10,9 +14,12 @@ TOKEN = ""
 
 class BankBot():
     def __init__(self):
-        self.application = Application.builder().token(TOKEN).build()
-        self.application.add_handler(CommandHandler('shop', self.addShop))
-        self.application.add_handler(MessageHandler(filters.ALL, self.response))
+        self.updater = Updater(TOKEN, use_context=True)
+        self.dispatcher = self.updater.dispatcher
+        self.dispatcher.add_handler(CommandHandler('start',   self.start))
+        self.dispatcher.add_handler(CommandHandler('add',   self.add))
+        self.dispatcher.add_handler(MessageHandler(Filters.text, self.echo))
+        self.clients = {}
 
         if os.path.isfile('./client.json'):
             with open("client.json") as fp:
@@ -21,28 +28,23 @@ class BankBot():
             self.clients = {}
 
     def start_polling(self):
-        print("start...")
-        self.application.run_polling()
-        
-    async def response(self, update, context):
-        q = update.message.text
-        
-        await context.bot.send_message(
-            chat_id=update.effective_chat.id,
-            text="我看不懂這個 {} 指令".format(q)
-        )
+        self.updater.start_polling()
 
-    async def addShop(self, update, context):
+    def echo(self, update, context):
+        message = update.message.text
+        context.bot.send_message(chat_id=update.effective_chat.id, text="我看不懂 {} 指令".format(message))
+
+    def add(self, update, context):
         args = context.args
+
         if len(args) != 1:
-            await context.bot.send_message(
-                chat_id=update.effective_chat.id,
-                text="usage: /shop [YOUR_ADDRESS]"    
-            )
+            context.bot.send_message(chat_id=update.effective_chat.id, text="usage: /start YOUR_ADDRESS")
         else:
             address = args[0]
-            this.client[address] = update.effective_chat.id
-            await context.bot.send_message(
-                chat_id=update.effective_chat.id,
-                text="已經設定 {} 的店家收款通知！"
-            )
+            self.clients[address] = update.effective_chat.id
+            with open('client.json', 'w') as fp:
+                json.dump(self.clients, fp)
+            context.bot.send_message(chat_id=update.effective_chat.id, text="開始追蹤 {} 的出入帳通知".format(address))
+
+    def start(self, update, context):
+        context.bot.send_message(chat_id=update.effective_chat.id, text="Hi, 這是暨大區塊鏈銀行 Telegram Bot\n\n/add YOUR_ADDRESS: 追蹤出入帳通知")

backend/main.py

@@ -3,6 +3,9 @@ import sqlite3
 import os
 from flask_cors import CORS
 from bot import BankBot
+import time
+import threading
+from blockchain_listener import Listener
 
 app = Flask(__name__)
 CORS(app)
@@ -169,14 +172,17 @@ def add_products(address):
     
     return jsonify({'status': 'OK'})
 
-
+def start_flask():
+    app.run(host="0.0.0.0")
 
 if __name__ == '__main__':
     initDB()
-    
-    app.run(host="0.0.0.0")
-
-    print("start the bot...")
     bot = BankBot()
+    print("start polling...")
     bot.start_polling()
-    bot.application.idle()
+
+    flask_thread = threading.Thread(target=start_flask)
+    flask_thread.start()
+
+    listener = Listener(bot)
+    listener.start()