Pepesan a.k.a Penjawab Pesan (Message Responder) is a simple and reliable JavaScript library to create a chat bot for WhatsApp, support for message pattern, routing, controller, and middleware similar to common REST API development framework such as Laravel.

Thanks To

• @whiskeysockets for the awesome WhatsApp socket library Baileys

Installation

> npm i --save pepesan

or directly install from the repository to get the latest beta version

> npm i --save github:mqad21/pepesan

Usage

# Initialization

index.js

const Pepesan = require("pepesan");
const router = require("./router");
(async () => {
    const pepesan = Pepesan.init(router)
    await pepesan.connect()
})()

You can add some configurations in second parameter.

index.js

const Pepesan = require("pepesan");
const router = require("./router");

(async () => {
    const config = {
        browserName: 'My first chat bot',
        sessionPath: './example/session',
        allowedNumbers: ['6281234567890', '6289876543210'],
        db: {
            path: './example/data.sqlite',
            username: 'mqad21',
            password: '4dm!n'
        }
    }
    
    const pepesan = Pepesan.init(router, config)
    await pepesan.connect()
})()

# Define a Router

Router is an instance of Router class. Here you define some rules for bot replies.

router.js

const { Router, Response } = require("pepesan")
const BotController = require("./BotController")

const router = new Router()

/**
 * If user send "ping",
 * bot will reply "pong".
 */ 
router.keyword("ping", () => {
    return "pong"
})

/**
 * If user send "ping 3 times",
 * method pingManyTimes in BotController will be called
 * and "3" will be passed as parameter.
 */
router.keyword("ping {n} times", [BotController, 'pingManyTimes'])

/**
 * If user send "get my number"
 * and the state is equal to "loggedIn",
 * method getMyNumber in BotController will be called.
 */
router.state("loggedIn").group(() => {
    router.keyword("get my number", [BotController, 'getMyNumber'])
})

/**
 * If user send "buy"
 * or user click a button with value "buy"
 * and AuthMiddleware function return true,
 * method buy in BotController will be called.
 */
router.middleware(AuthMiddleware).group(() => {
    router.keyword("buy", [BotController, 'buy'])
    router.button("buy", [BotController, 'buy'])
})

module.exports = router

# Define a Controller

Controller is a class that extends Controller class.

BotController.js

const { Controller, Response } = require("pepesan")

module.exports = class BotController extends Controller {

    /**
     * Bot will reply "pong" n times.
     */
    pingManyTimes(request, n) {
        return Array(Number(n)).fill("pong") // ["pong", "pong", ..., "pong"] n times
    }

    /**
     * Bot will reply "Wait for a while..."
     * then bot will reply an image
     * after it has been received from server.
     */
    async pingWithImage() {
        await this.reply(Response.text.fromString("Wait for a while..."))
        const image = await getImageFromServer()
        return Response.image.fromBuffer(image)
    }

    /**
     * Bot will reply user WhatsApp number.
     */
    getMyNumber(request) {
        return request.number
    }

    /**
     * Bot will reply button "yes" and "cancel"
     * with "Are you sure?" text.
     */
    buy() {
        const buttons = ["yes", "cancel"]
        return Response.button.fromArrayOfString(buttons, "Are you sure?")
    }

}

# Define a Middleware

Middleware is an async/sync function that return Boolean or Response.

AuthMiddleware.js

const { Response } = require("pepesan")

module.exports = (request, next) => {

    /**
     * If user number is not equal to "6281234567890",
     * bot will reply "You are not allowed"
     * else bot will execute the routes below it.
     */
    if (request.number !== "6281234567890") {
        return "You are not allowed"
    }
    return next()

}

Documentation

# Configuration

{
    printQRInTerminal: boolean // default: true
    sessionPath: string, // default: "./session"
    browserName: string, // default: "Pepesan"
    allowedNumbers: string[],
    blockedNumbers: string[],
    onOpen: (state: Partial<ConnectionState>) => void
    onClose: (state: Partial<ConnectionState>) => void
    onReconnect: (state: Partial<ConnectionState>) => void
    onQR: (state: Partial<ConnectionState>) => void,
    onMessage: (message: WAMessage) => Promise<void>,
    db: {
        name: string,
        user: string,
        pass: string,
        path: string // default: "data.sqlite"
    }
}

• printQRInTerminal: indicates whether or not the QR code should be print in terminal.
• sessionPath: folder path to save session files.
  e.g. "/mysession"
• browserName: name that display in the device list of your WhatsApp app.
• allowedNumbers: list of number you allowed for using bot. Let in null or undefined if you want to allow all numbers.
  e.g. ["6281234567890", "6289876543210"]
• blockedNumbers: list of number you blocked for using bot. Let in null or undefined if you want to allow all numbers.
  e.g. ["6281234567890", "6289876543210"]
• onOpen: a callback function when WhatsApp connection opened.
• onClose: a callback function when WhatsApp connection closed.
• onClose: a callback function when WhatsApp connection needs to reconnect.
• onQR: a callback function when WhatsApp QR code received.
• onMessage: a callback function when a new message received.
• db: configurations for your SQLite database.
  • name: Database name.
  • user: Database username.
  • pass: Database password.
  • path: Path to your ".sqlite" file.
    e.g. "/data.sqlite"'

# Router

1. Keyword Route

Keyword route handles user's message, media caption, or button response text that match the route pattern.

router.keyword("hello", ...) // only match to "hello" text.
router.keyword("hello*", ...) // match to all texts start with "hello".
router.keyword("(hello|hi)", ...) // only match to "hello" or "hi" text.
router.keyword("hello {name}", ...) // match to "hello muhammad", "hello qadri", etc.

2. State Route

State route handles user's state that match with the route pattern.

router.state("idle", ...) // only match to "idle" state.
router.state("idle*", ...) // match to all states start with "idle".
router.state("(idle|active)", ...) // only match to "idle" or "active" state.
router.state("active {time}", ...) // match to "active today", "active tonight", etc.

3. Middleware Route

Middleware route handles all user's message if only middleware function return true.

router.middleware(AuthMiddleware, ...) // if AuthMiddleware return true, the callback will be called.
router.middleware([AuthMiddleware, param1, param2, ...], ...) // Middleware also can receive parameters.

4. Button Route

Button route handles text or value of button clicked by user that match with the route pattern.

router.button("buy", ...) // only match to "buy" button text or value.
router.button("buy*", ...) // match to all button values or texts that start with "buy".
router.button("(buy|cancel)", ...) // only match to "buy" or "cancel" button text or value.
router.button("buy {product}", ...) // match to "buy iphone", "buy macbook", etc.

5. Grouping Route

Route can also be grouped if the callback or the second parameter is not set.

router.middleware([AuthMiddleware, 'change settings']).group(() => {
    // Code block below is only executed if AuthMiddleware function returns true.
    router.keyword("Change payment to (cash|transfer)", [PaymentController, 'changePayment'])
    router.button("Change profile", [ProfileController, 'changeProfile'])
})

router.state("loggedIn").group(() => {
    // Code block below is only executed if user state equals to "loggedIn".
    router.keyword("View my balance", [BalanceController, 'viewBalance'])
    router.button("View my profile", [ProfileController, 'viewProfile'])
})

# Controller

1. Own method

• Controller method can be an async/sync function.

• The first parameter is Request object and the rest is route parameter.

• The return value is the response message of bot. It can be string or Response object.

• If you want the bot respond more than one message, you can make the return value as Array.

  Example:

  introduction(request, firstName, lastName) {
      return `Hello ${firstName} ${lastName}`
  }
  
  pingTwoTimes(request) {
      return ["Ping 1", "Ping 2"]
  }
  
  async downloadYoutube(request) {
      const url = request.text
      const youtube = await download(url)
      return [
          Response.video.fromBuffer(youtube.video),
          youtube.title
      ]
  }

2. reply(response)

• The reply method is used to reply to the user's message.

• The parameter can be string, Response, Array of string, Array of Response, or Array of Response or string.

  Example:

  async convertToMp3(request) {
      await this.reply("Please wait...")
      await this.reply(Response.image.fromURL("..."))
      const url = request.text
      const mp3 = await toMp3(url)
      return Response.audio.fromBuffer(mp3)
  }

3. send(number, response)

• The send method is used to send message to the another user.

• The first parameter is recipient WhatsApp number.

• The second parameter can be string, Response, Array of string, Array of Response, or Array of Response or string.

  Example:

  async sendConfirm(request) {
      const message = request.text
      await this.send("6289876543210", [
          message,
          Response.image.fromURL("...")
      ])
      return "Confirmed"
  }

4. getMedia()

• The getMedia method is used to get any media sent by user.

• The return of this method is Promise<Buffer>

  Example:

  async uploadReceipt(request) {
      const receipt = await this.getMedia()
      await this.send("6289876543210", Response.image.fromBuffer(receipt))
      return "Uploaded"
  }

5. setState(state)

• The setState method is used to set current user state.

• The parameter is state string.

  Example:

  async login(request) {
      const key = request.text
      const isAllowed = await checkKey(key)
      if (isAllowed) {
          await this.setState("loggedIn")
          return "You are logged in"
      }
      return "Invalid key"
  }

6. deleteState()

• The deleteState method is used to delete the current user state.

  Example:

  async logout(request) {
      await this.deleteState()
      return "Logged out"
  }

# Request

Request is an object that contains information from the user's message.
Example:

{
    id: '3EB00744EB342283C522', // Message ID
    key: ..., // Message key object
    text: "Hello", // Message text or caption
    button: ..., // { text: "Button text", value: "Button value or ID" }
    jid: "[email protected]", // User's JID
    number: "6281234567890", // User's WhatsApp number
    name: "Muhammad Qadri", // User's name
    state: "MyState", // Current user's state
    stateObject: ..., // User's state object
    type: ..., // 'image' | 'video' | 'document' | 'sticker'
    message: ..., // Message object
    document: ..., // Document message object
    image: ..., // Video message object
    sticker: ..., // Sticker message object
    contact: ..., // Contact message object
    route: ... // Current route object 
}

# Response

1. Text Response

Response.text.fromString("Assalamu'alaikum brother")

2. Image Response

Response.image.fromBuffer(imageBuffer, "caption")
Response.image.fromURL("https://upload.wikimedia.org/wikipedia/commons/thumb/6/6b/WhatsApp.svg/2044px-WhatsApp.svg.png", "caption")

3. Video Response

Response.video.fromBuffer(videoBuffer, "caption")
Response.video.fromStream(videoStream, "caption")
Response.video.fromURL("http://techslides.com/demos/sample-videos/small.mp4", "caption")

4. Audio Response

Response.audio.fromBuffer(webpBuffer)
Response.audio.fromURL("https://download.quranicaudio.com/quran/wadee_hammadi_al-yamani/001.mp3")

5. Sticker Response

Response.sticker.fromBuffer(webpBuffer)
Response.sticker.fromURL("https://raw.githubusercontent.com/mqad21/pepesan-assets/main/sticker.webp")

6. Button Response

Response.button.fromArrayOfString(["yes", "cancel"], "Content", "Footer")
Response.button.fromArrayOfObject([{text: "yes", value: "1"}, {text:"no", value: "0"}], "Content", "Footer")

# Middleware

• Middleware is an async/sync function that return Boolean or Response value

• The first parameter is Request object.

• The second parameter is next function.

• The rest is route parameter.

  Example:

  (request, next, action) => {
      if (request.number !== "6281234567890") {
          let errorMessage = "You are not allowed"
          if (action) errorMessage += ` to ${action}`
          return errorMessage
      }
      return next()
  }

# Global Variable

1. sock

Access to WASocket object anywhere after initiate the Pepesan class.

2. db

Access to Database object anywhere after initiate the Pepesan class.