Facebook bot example

.babel.rc

{
  "presets": [
    "es2015",
    "stage-0"
  ]
}

fbbot.js

import express from 'express'
import bodyParser from 'body-parser'
import request from 'request'

const config = {
  VERIFY_TOKEN: process.env.VERIFY_TOKEN || 'token',
  PAGE_TOKEN: process.env.PAGE_TOKEN || 'token',
}

const app = express()
const port = (process.env.PORT || 5678)

app.use(bodyParser.json())
app.use(bodyParser.urlencoded({extended: true}))

app.get('/webhook', (req, res) => {
  if (req.query['hub.verify_token'] === config.VERIFY_TOKEN) {
    res.send(req.query['hub.challenge'])
  } else {
    res.send('Error, wrong validation token')
  }
})

app.post('/webhook', (req, res) => {
  console.log(req.body)

  req.body.entry.forEach((entry) => {
    entry.messaging.forEach((event) => {
      if (event.message) {
        sendTextMessage({
          id: event.sender.id,
          text: event.message.text,
        })
      } else {
        console.log('unknown event!!!', event)
      }
    })
  })

  res.sendStatus(200)
})

app.listen(port, () => console.log(`listening on port ${port}`))

function sendTextMessage({id, text}) {
  request({
    url: 'https://graph.facebook.com/v2.6/me/messages',
    qs: {
      access_token: config.PAGE_TOKEN,
    },
    method: 'POST',
    json: {
      recipient: {
        id,
      },
      message: {
        text,
      }
    }
  }, (error, response, body) => {
    console.log('Error: ', error || response.body.error)
  })
}

package.json

{
  "name": "fbbot",
  "version": "0.0.1",
  "description": "facebook bot example",
  "main": "src/index.js",
  "scripts": {
    "build": "./node_modules/.bin/babel index.js -d dist",
    "start": "node ./index.js"
  },
  "author": "Jimmy Chao",
  "license": "ISC",
  "dependencies": {
    "body-parser": "^1.15.2",
    "express": "^4.14.0",
    "request": "^2.75.0"
  },
  "devDependencies": {
    "babel-cli": "^6.16.0",
    "babel-core": "^6.17.0",
    "babel-preset-es2015": "^6.16.0",
    "babel-preset-stage-0": "^6.16.0",
    "foreman": "^2.0.0"
  }
}

Procfile

web: npm start