index.ts

import * as functions from 'firebase-functions'
import * as admin from 'firebase-admin'
import 'firebase-functions'
import express from 'express'
import { middleware, Client } from '@line/bot-sdk'
admin.initializeApp()
export const bot = functions.https.onRequest((req, res) => {
  const config = {
    channelAccessToken: functions.config().line.channel.accesstoken,
    channelSecret: functions.config().line.channel.secret
  }
  middleware(config)(req, res, err => {
    if (err) {
      console.error('LINE bot middleware error:', err)
      res.status(500).send('LINE bot middleware error')
      return
    }
    const client = new Client(config)
    for (const event of req.body.events) {
      if (event.type === 'message') {
        client.replyMessage(event.replyToken, [{ type: 'text', text: 'meow' }])
      }
    }
  })
})