main.py

from fastapi.middleware.cors import CORSMiddleware
from fastapi import FastAPI

import json
import os

from linebot import (
    LineBotApi, WebhookHandler
)
from linebot.exceptions import (
    InvalidSignatureError
)
from linebot.models import (
    MessageEvent, TextMessage, TextSendMessage, ImageSendMessage, AudioMessage
)

app = FastAPI()
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

line_bot_api = LineBotApi("ZwnEWwK46AUmRDOFXJOwUh1TqAELahP+kxHY0iBevF8JiEUe0CBQpkW2Gpo3C38LOaIX7hpW4IuTOSOjVof+DX9XgZg8MTeh5Iz+NDLlw6KKMtqNsyR6zt9CMnsso21ieifC/S8dcgXx3iKlhdS7UAdB04t89/1O/w1cDnyilFU=")
line_handler = WebhookHandler("7b9984bbc5c62445a79b95b15e34b727")

working_status = os.getenv("DEFALUT_TALKING", default = "true").lower() == "true"

@app.get("/")
 def root():
     return {"title": "Echo Bot"}

 @app.post("/webhook")
 async def callback(request: Request)
    # get X-Line-Signature header value
    signature = request.headers['X-Line-Signature']
    # get request body as text
    body = request.get_data(as_text=True)
    app.logger.info("Request body: " + body)
    # handle webhook body
    try:
        line_handler.handle(body, signature)
    except InvalidSignatureError:
        abort(400)
    return 'OK'

@line_handler.add(MessageEvent, message=TextMessage)
def handle_message(event):
    global working_status

    if event.message.text == "再見":
        working_status = True
        line_bot_api.reply_message(
            event.reply_token,
            TextSendMessage(text="Bye!"))
        return

    if working_status:
        out = event.message.text
        if not out:
            out = "不懂您的意思!"
        line_bot_api.reply_message(
            event.reply_token,
            TextSendMessage(text=out))