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Create a ChatGPT-powered AI chat bot using Node.js

Turn your WhatsApp number into a ChatGPT-powered AI powerful chatbot in minutes with this tutorial using the Wassenger API. 🤩 🤖

By following this tutorial you will be able to have a fully functional ChatGPT-like AI chatbot running in minutes on your computer or cloud server that behaves like a virtual customer support assistant for a specific business purpose.

The chatbot will be able to understand and speak many languages and has been trained to behave like a customer support virtual assistant specialized in certain tasks.

If you a are developer, jump directly to the code here

🤩 You can also train the AI bot with your customized instructions in order to customize the bot behavior. Also, the AI bot will be conversation-aware based on the previous messages you had with the user on WhatsApp, providing more context-specific accurate responses.

How it works

  1. Starts a web service that automatically connects to the Wassenger API and your WhatsApp number
  2. Creates a tunnel using Ngrok to be able to receive Webhook events on your computer (or you can use a dedicated webhook URL instead if you run the bot program in your cloud server).
  3. Registers the webhook endoint automatically in order to receive incoming messages.
  4. Processes and replies to messages received using a ChatGPT-powered AI model trained with custom instructions.
  5. You can start playing with the AI bot by sending messages to the Wassenger connected WhatsApp number.

Features

This tutorial provides a complete ChatGPT-powered AI chatbot implementation in Node.js that:

  • Provides a fully featured chatbot in your WhatsApp number connected to Wassenger
  • Replies automatically to any incoming messages from arbitrary users
  • Can understand any text in natural language and reply in 90+ different human languages
  • Allows any user to ask talking with a human, in which case the chat will be assigned to an agent and exit the bot flow
  • AI bot behavior can be easily adjusted in the configuration file

Bot behavior

The AI bot will always reply to inbound messages based on the following criteria:

  • The chat belong to a user (group chats are always ignored)
  • The chat is not assigned to any agent inside Wassenger
  • The chat has not any of the blacklisted labels (see config.js)
  • The chat user number has not been blacklisted (see config.js)
  • The chat or contact has not been archived or blocked
  • If a chat is unassigned from an agent, the bot will take over it again and automatically reply to new incoming messages

Requirements

Project structure

\
 |- bot.js -> the bot source code in a single file
 |- config.js -> configuration file to customize credentials and bot behavior
 |- actions.js -> functions to perform actions through the Wassenger API
 |- server.js -> initializes the web server to process webhook events
 |- main.js -> initializes the bot server and creates the webhook tunnel (when applicable)
 |- store.js -> the bot source code in a single file
 |- package.json -> node.js package manifest required to install dependencies
 |- node_modules -> where the project dependencies will be installed, managed by npm

Configuration

Open your favorite terminal and change directory to project folder where package.json is located:

cd ~/Downloads/whatsapp-chatgpt-bot/

From that folder, install dependencies by running:

npm install

With your preferred code editor, open config.js file and follow the steps below.

Set your Wassenger API key

Enter your Wassenger API key (sign up here for free) and obtain the API key here:

// Required. Specify the Wassenger API key to be used
// You can obtain it here: https://app.wassenger.com/apikeys
apiKey: env.API_KEY || 'ENTER API KEY HERE',

Set your OpenAI API key

Enter your OpenAI API key (sign up here for free) and obtain the API key here:

// Required. Specify the OpenAI API key to be used
// You can sign up for free here: https://platform.openai.com/signup
// Obtain your API key here: https://platform.openai.com/account/api-keys
openaiKey: env.OPENAI_API_KEY || 'ENTER OPENAI API KEY HERE',

Set your Ngrok token (optional)

If you need to run the program on your local computer, the program needs to create a tunnel using Ngrok in to process webhook events for incoming WhatsApp messages.

Sign up for a Ngrok free account and obtain your auth token as explained here. Then set the token in the line 90th:

// Ngrok tunnel authentication token.
// Required if webhook URL is not provided.
// sign up for free and get one: https://ngrok.com/signup
// Learn how to obtain the auth token: https://ngrok.com/docs/agent/#authtokens
ngrokToken: env.NGROK_TOKEN || 'ENTER NGROK TOKEN HERE',
If you run the program in a cloud server that is publicly accesible from the Internet, you don't need to use Ngrok. Instead, set your server URL in config.js > webhookUrl field.

Customization

You can customize the chatbot behavior by defining a set of instructions in natural language that the AI will follow.

Read the comments for further instructions.

That's it! You can now test the chatbot from another WhatsApp number

You're welcome to adjust the code to fit your own needs. The possibilities are nearly endless!

To do so, open config.js in with your preferred code editor and set the instructions and default message based on your preferences:

// Default message when the user sends an unknown message.
const unknownCommandMessage = `I'm sorry, I can only understand text. Can you please describe your query?

If you would like to chat with a human, just reply with *human*.`

// Default welcome message. Change it as you need.
const welcomeMessage = `Hey there 👋 Welcome to this ChatGPT-powered AI chatbot demo using *Wassenger API*! I can also speak many languages 😁`

// AI bot instructions to adjust its bevarior. Change it as you need.
// Use concise and clear instructions.
const botInstructions = `You are an smart virtual customer support assistant that works for Wassenger.
You can identify yourself as Molly, the Wassenger chatbot assistant.
You will be chatting with random customers who may contact you with general queries about the product.
Wassenger is a cloud solution that offers WhatsApp API and multi-user live communication services designed for businesses and developers.
Wassenger also enables customers to automate WhatsApp communication and build chatbots.
You are an expert in customer support. Be polite, be gentle, be helpful and emphatic.
Politely reject any queries that are not related to customer support or Wassenger itself.
Strictly stick to your role as customer support virtual assistant for Wassenger.
If you can't help with something, ask the user to type *human* in order to talk with customer support.`

// Default help message. Change it as you need.
const defaultMessage = `Don't be shy 😁 try asking anything to the AI chatbot, using natural language!

Example queries:

1️⃣ Explain me what is Wassenger
2️⃣ Can I use Wassenger to send automatic messages?
3️⃣ Can I schedule messages using Wassenger?
4️⃣ Is there a free trial available?

Type *human* to talk with a person. The chat will be assigned to an available member of the team.

Give it a try! 😁`

Usage

Run the bot program:

node main

Run the bot program on a custom port:

PORT=80 node main

Run the bot program for a specific Wassenger connected device:

DEVICE=WHATSAPP_DEVICE_ID node main

Run the bot program in production mode:

NODE_ENV=production node main

Run the bot with an existing webhook server without the Ngrok tunnel:

WEBHOOK_URL=https://bot.company.com:8080/webhook node main
Note: https://bot.company.com:8080 must point to the bot program itself running in your server and it must be network reachable using HTTPS for secure connection.

Source files

Download all project files clicking on the Download icon in the box top-right corner below.

const { env } = process

// Default message when the user sends an unknown message.
const unknownCommandMessage = `I'm sorry, I can only understand text. Can you please describe your query?

If you would like to chat with a human, just reply with *human*.`

// Default welcome message. Change it as you need.
const welcomeMessage = `Hey there 👋 Welcome to this ChatGPT-powered AI chatbot demo using *Wassenger API*! I can also speak many languages 😁`

// AI bot instructions to adjust its bevarior. Change it as you need.
// Use concise and clear instructions.
const botInstructions = `You are a smart virtual customer support assistant who works for Wassenger.
You can identify yourself as Molly, the Wassenger chatbot assistant.
You will be chatting with random customers who may contact you with general queries about the product.
Wassenger is a cloud solution that offers WhatsApp API and multi-user live communication services designed for businesses and developers.
Wassenger also enables customers to automate WhatsApp communication and build chatbots.
You are an expert customer support agent.
Be polite. Be gentle. Be helpful. Be emphatic. Be concise in your responses.
Politely reject any queries that are not related to customer support or Wassenger itself.
Strictly stick to your role as customer support virtual assistant for Wassenger.
If you can't help with something, ask the user to type *human* in order to talk with customer support.`

// Default help message. Change it as you need.
const defaultMessage = `Don't be shy 😁 try asking anything to the AI chatbot, using natural language!

Example queries:

1️⃣ Explain me what is Wassenger
2️⃣ Can I use Wassenger to send automatic messages?
3️⃣ Can I schedule messages using Wassenger?
4️⃣ Is there a free trial available?

Type *human* to talk with a person. The chat will be assigned to an available member of the team.

Give it a try! 😁`

// Optional. AI callable functions to be interpreted by the AI
// Using it you can instruct the AI to inform you to execute arbitrary functions
// in your code based in order to augment information for a specific user query.
// For example, you can call an external CRM in order to retrieve, save or validate
// specific information about the customer, such as email, phone number, user ID, etc.
// Learn more here: https://platform.openai.com/docs/guides/gpt/function-calling
const openaiFunctions = [
  {
    name: 'getPlanPrices',
    description: 'Get available plans and prices information available in Wassenger',
    parameters: { type: 'object', properties: {} }
  }
]

// Optional. Edit as needed to cover your business use cases.
// Note the method property name for every function must be equal the openaiFunctions[].name property.
// Collection of callable function calls used to generate the response to feed the AI model
// and generate a domain-specific response to the user.
// Functions may be synchronous or asynchronous.
// Learn more here: https://platform.openai.com/docs/guides/gpt/function-calling
const functions = {
  async getPlanPrices ({ response, data, device, messages }) {
    const message = [
      '*Gateway plans: Send only messages + API*',
      '',
      '- Gateway Professional: up to 10,000 outbound messages',
      '- Gateway Business: up to 30,000 outbound messages',
      '- Gateway Enterprise: unlimited outbound messages',
      '',
      '*Platform plans: Send & Receive messages + API + Webhooks + Live Team Chat + CRM + Analytics*',
      '',
      '- Platform Professional: up to 30,000 outbound + unlimited inbound messages',
      '- Platform Business: up to 60,000 outbound + unlimited inbound messages',
      '- Platform Enterprise: unlimited: unlimited outbound + inbound messages',
      '',
      'Each plan is limited to one WhatsApp number. You can purchase multiple plans for multiple numbers.',
      '',
      '*Find more information about the different plan prices and features here:*',
      'https://wassenger.com/#pricing'
    ].join('\n')
    return message
  }
}

// Chatbot config
export default {
  // Optional. Specify the Wassenger device ID (24 characters hexadecimal length) to be used for the chatbot
  // If no device is defined, the first connected device will be used
  // Obtain the device ID in the Wassenger app: https://app.wassenger.com/number
  device: env.DEVICE || 'ENTER WHATSAPP DEVICE ID',

  // Required. Specify the Wassenger API key to be used
  // You can obtain it here: https://app.wassenger.com/apikeys
  apiKey: env.API_KEY || 'ENTER API KEY HERE',

  // Required. Specify the OpenAI API key to be used
  // You can sign up for free here: https://platform.openai.com/signup
  // Obtain your API key here: https://platform.openai.com/account/api-keys
  openaiKey: env.OPENAI_API_KEY || '',

  // Required. Set the OpenAI model to use.
  // You can use a pre-existing model or create your fine-tuned model.
  // Default model (fastest and cheapest): gpt-3.5-turbo-0125
  // Newest model: gpt-4-1106-preview
  // For customized fine-tuned models, see: https://platform.openai.com/docs/guides/fine-tuning
  openaiModel: env.OPENAI_MODEL || 'gpt-3.5-turbo-0125',

  // Optional. AI callable functions to be interpreted by the AI
  // Using it you can instruct the AI to inform you to execute arbitrary functions
  // in your code based in order to augment information for a specific user query.
  // For example, you can call an external CRM in order to retrieve, save or validate
  // specific information about the customer, such as email, phone number, user ID, etc.
  // Learn more here: https://platform.openai.com/docs/guides/gpt/function-calling
  openaiFunctions,

  // Optional. Edit as needed to cover your business use cases.
  // Note the method property name for every function must be equal the openaiFunctions[].name property.
  // Collection of callable function calls used to generate the response to feed the AI model
  // and generate a domain-specific response to the user.
  // Functions may be synchronous or asynchronous.
  // Learn more here: https://platform.openai.com/docs/guides/gpt/function-calling
  functions,

  // Optional. HTTP server TCP port to be used. Defaults to 8080
  port: +env.PORT || 8080,

  // Optional. Use NODE_ENV=production to run the chatbot in production mode
  production: env.NODE_ENV === 'production',

  // Optional. Specify the webhook public URL to be used for receiving webhook events
  // If no webhook is specified, the chatbot will autoamtically create an Ngrok tunnel
  // and register it as the webhook URL.
  // IMPORTANT: in order to use Ngrok tunnels, you need to sign up for free, see the option below.
  webhookUrl: env.WEBHOOK_URL,

  // Ngrok tunnel authentication token.
  // Required if webhook URL is not provided.
  // sign up for free and get one: https://ngrok.com/signup
  // Learn how to obtain the auth token: https://ngrok.com/docs/agent/#authtokens
  ngrokToken: env.NGROK_TOKEN,

  // Optional. Full path to the ngrok binary.
  ngrokPath: env.NGROK_PATH,

  // Set one or multiple labels on chatbot-managed chats
  setLabelsOnBotChats: ['bot'],

  // Remove labels when the chat is assigned to a person
  removeLabelsAfterAssignment: true,

  // Set one or multiple labels on chatbot-managed chats
  setLabelsOnUserAssignment: ['from-bot'],

  // Optional. Set a list of labels that will tell the chatbot to skip it
  skipChatWithLabels: ['no-bot'],

  // Optional. Ignore processing messages sent by one of the following numbers
  // Important: the phone number must be in E164 format with no spaces or symbols
  numbersBlacklist: ['1234567890'],

  // Optional. Only process messages one of the the given phone numbers
  // Important: the phone number must be in E164 format with no spaces or symbols
  numbersWhitelist: [],

  // Skip chats that were archived in WhatsApp
  skipArchivedChats: true,

  // If true, when the user requests to chat with a human, the bot will assign
  // the chat to a random available team member.
  // You can specify which members are eligible to be assigned using the `teamWhitelist`
  // and which should be ignored using `teamBlacklist`
  enableMemberChatAssignment: true,

  // If true, chats assigned by the bot will be only assigned to team members that are
  // currently available and online (not unavailable or offline)
  assignOnlyToOnlineMembers: false,

  // Optional. Skip specific user roles from being automatically assigned by the chat bot
  // Available roles are: 'admin', 'supervisor', 'agent'
  skipTeamRolesFromAssignment: ['admin'], // 'supervisor', 'agent'

  // Enter the team member IDs (24 characters length) that can be eligible to be assigned
  // If the array is empty, all team members except the one listed in `skipMembersForAssignment`
  // will be eligible for automatic assignment
  teamWhitelist: [],

  // Optional. Enter the team member IDs (24 characters length) that should never be automatically assigned chats to
  teamBlacklist: [],

  // Optional. Set metadata entries on bot-assigned chats
  setMetadataOnBotChats: [
    {
      key: 'bot_start',
      value: () => new Date().toISOString()
    }
  ],

  // Optional. Set metadata entries when a chat is assigned to a team member
  setMetadataOnAssignment: [
    {
      key: 'bot_stop',
      value: () => new Date().toISOString()
    }
  ],

  defaultMessage,
  botInstructions,
  welcomeMessage,
  unknownCommandMessage,
}
import OpenAI from 'openai'
import config from './config.js'
import { state } from './store.js'
import * as actions from './actions.js'

// Initialize OpenAI client
const ai = new OpenAI({ apiKey: config.openaiKey })

// Determine if a given inbound message can be replied by the AI bot
function canReply ({ data, device }) {
  const { chat } = data

  // Skip if chat is already assigned to an team member
  if (chat.owner && chat.owner.agent) {
    return false
  }

  // Ignore messages from group chats
  if (chat.type !== 'chat') {
    return false
  }

  // Skip replying chat if it has one of the configured labels, when applicable
  if (config.skipChatWithLabels && config.skipChatWithLabels.length && chat.labels && chat.labels.length) {
    if (config.skipChatWithLabels.some(label => chat.labels.includes(label))) {
      return false
    }
  }

  // Only reply to chats that were whitelisted, when applicable
  if (config.numbersWhitelist && config.numbersWhitelist.length && chat.fromNumber) {
    if (config.numbersWhitelist.some(number => number === chat.fromNumber || chat.fromNumber.slice(1) === number)) {
      return true
    } else {
      return false
    }
  }

  // Skip replying to chats that were explicitly blacklisted, when applicable
  if (config.numbersBlacklist && config.numbersBlacklist.length && chat.fromNumber) {
    if (config.numbersBlacklist.some(number => number === chat.fromNumber || chat.fromNumber.slice(1) === number)) {
      return false
    }
  }

  // Skip replying chats that were archived, when applicable
  if (config.skipArchivedChats && (chat.status === 'archived' || chat.waStatus === 'archived')) {
    return false
  }

  // Always ignore replying to banned chats/contacts
  if ((chat.status === 'banned' || chat.waStatus === 'banned  ')) {
    return false
  }

  return true
}

// Send message back to the user and perform post-message required actions like
// adding labels to the chat or updating the chat's contact metadata
function replyMessage ({ data, device }) {
  return async ({ message, ...params }) => {
    const { phone } = data.chat.contact

    await actions.sendMessage({
      phone,
      device: device.id,
      message,
      ...params
    })

    // Add bot-managed chat labels, if required
    if (config.setLabelsOnBotChats.length) {
      const labels = config.setLabelsOnBotChats.filter(label => (data.chat.labels || []).includes(label))
      if (labels.length) {
        await actions.updateChatLabels({ data, device, labels })
      }
    }

    // Add bot-managed chat metadata, if required
    if (config.setMetadataOnBotChats.length) {
      const metadata = config.setMetadataOnBotChats.filter(entry => entry && entry.key && entry.value).map(({ key, value }) => ({ key, value }))
      await actions.updateChatMetadata({ data, device, metadata })
    }
  }
}

// Process message received from the user on every new inbound webhook event
export async function processMessage ({ data, device } = {}) {
  // Can reply to this message?
  if (!canReply({ data, device })) {
    return console.log('[info] Skip message due to chat already assigned or not eligible to reply:', data.fromNumber, data.date, data.body)
  }

  const reply = replyMessage({ data, device })
  const { chat } = data
  const body = data?.body?.trim().slice(0, 1000)

  console.log('[info] New inbound message received:', chat.id, body || '<empty message>')

  // First inbound message, reply with a welcome message
  if (!data.chat.lastOutboundMessageAt || data.meta.isFirstMessage) {
    const message = `${config.welcomeMessage}\n\n${config.defaultMessage}}`
    return await reply({ message })
  }

  if (!body) {
    // Default to unknown command response
    const unknownCommand = `${config.unknownCommandMessage}\n\n${config.defaultMessage}`
    await reply({ message: unknownCommand })
  }

  // Assign the chat to an random agent
  if (/^human|person|help|stop$/i.test(body) || /^human/i.test(body)) {
    actions.assignChatToAgent({ data, device }).catch(err => {
      console.error('[error] failed to assign chat to user:', data.chat.id, err.message)
    })
    return await reply({
      message: `This chat was assigned to a member of our support team. You will be contacted shortly.`,
    })
  }

  // Generate response using AI
  if (!state[data.chat.id]) {
    console.log('[info] fetch previous messages history for chat:', data.chat.id)
    await actions.pullChatMessages({ data, device })
  }

  // Compose chat previous messages to context awareness better AI responses
  const previousMessages = Object.values(state[data.chat.id] || {})
    .reverse()
    .slice(0, 40)
    .map(message => ({
      role: message.flow === 'inbound' ? 'user' : 'assistant',
      content: message.body
    }))
    .filter(message => message.content).slice(-20)

  const messages = [
    { role: 'system', content: config.botInstructions },
    ...previousMessages,
    { role: 'user', content: body }
  ]

  // Generate response using AI
  const completion = await ai.chat.completions.create({
    messages,
    temperature: 0.2,
    model: config.openaiModel,
    user: `${device.id}_${chat.id}`,
    functions: config.openaiFunctions || []
  })

  // Reply with the AI generated message
  if (completion.choices && completion.choices.length) {
    const [response] = completion.choices

    // If response is a function call, return the custom result
    if (response.message.function_call && response.message.function_call.name) {
      const func = config.functions[response.message.function_call.name]
      if (typeof func === 'function') {
        const message = await func({ response, data, device, messages })
        await reply({ message })
      } else {
        console.error('[warning] missing function call in config.functions', response.message.function_call.name)
      }
    }

    // Otherwise forward the AI generate message
    return await reply({ message: response.message.content || config.unknownCommandMessage })
  }

  // Unknown default response
  const unknownCommand = `${config.unknownCommandMessage}\n\n${config.defaultMessage}`
  await reply({ message: unknownCommand })
}
import axios from 'axios'
import config from './config.js'
import { state, cache, cacheTTL } from './store.js'

// Base URL API endpoint. Do not edit!
const API_URL = process.env.API_URL || 'https://api.wassenger.com/v1'

// Function to send a message using the Wassenger API
export async function sendMessage ({ phone, message, media, device, ...fields }) {
  const url = `${API_URL}/messages`
  const body = {
    phone,
    message,
    media,
    device,
    ...fields,
    enqueue: 'never'
  }

  let retries = 3
  while (retries) {
    retries -= 1
    try {
      const res = await axios.post(url, body, {
        headers: { Authorization: config.apiKey }
      })
      console.log('[info] Message sent:', phone, res.data.id, res.data.status)
      return res.data
    } catch (err) {
      console.error('[error] failed to send message:', phone, message || (body.list ? body.list.description : '<no message>'), err.response ? err.response.data : err)
    }
  }
  return false
}

export async function pullMembers (device) {
  if (cache.members && +cache.members.time && (Date.now() - +cache.members.time) < cacheTTL) {
    return cache.members.data
  }
  const url = `${API_URL}/devices/${device.id}/team`
  const { data: members } = await axios.get(url, { headers: { Authorization: config.apiKey } })
  cache.members = { data: members, time: Date.now() }
  return members
}

export async function validateMembers (device, members) {
  const validateMembers = (config.teamWhitelist || []).concat(config.teamBlacklist || [])
  for (const id of validateMembers) {
    if (typeof id !== 'string' || string.length !== 24) {
      return exit('Team user ID in config.teamWhitelist and config.teamBlacklist must be a 24 characters hexadecimal value:', id)
    }
    const exists = members.some(user => user.id === id)
    if (!exists) {
      return exit('Team user ID in config.teamWhitelist or config.teamBlacklist does not exist:', id)
    }
  }
}

export async function createLabels (device) {
  const labels = cache.labels.data || []
  const requiredLabels = (config.setLabelsOnUserAssignment || []).concat(config.setLabelsOnBotChats || [])
  const missingLabels = requiredLabels.filter(label => labels.every(l => l.name !== label))
  for (const label of missingLabels) {
    console.log('[info] creating missing label:', label)
    const url = `${API_URL}/devices/${device.id}/labels`
    const body = {
      name: label.slice(0, 30).trim(),
      color: [
        'tomato', 'orange', 'sunflower', 'bubble',
        'rose', 'poppy', 'rouge', 'raspberry',
        'purple', 'lavender', 'violet', 'pool',
        'emerald', 'kelly', 'apple', 'turquoise',
        'aqua', 'gold', 'latte', 'cocoa'
      ][Math.floor(Math.random() * 20)],
      description: 'Automatically created label for the chatbot'
    }
    try {
      await axios.post(url, body, { headers: { Authorization: config.apiKey } })
    } catch (err) {
      console.error('[error] failed to create label:', label, err.message)
    }
  }
  if (missingLabels.length) {
    await pullLabels(device, { force: true })
  }
}

export async function pullLabels (device, { force } = {}) {
  if (!force && cache.labels && +cache.labels.time && (Date.now() - +cache.labels.time) < cacheTTL) {
    return cache.labels.data
  }
  const url = `${API_URL}/devices/${device.id}/labels`
  const { data: labels } = await axios.get(url, { headers: { Authorization: config.apiKey } })
  cache.labels = { data: labels, time: Date.now() }
  return labels
}

export async function updateChatLabels ({ data, device, labels }) {
  const url = `${API_URL}/chat/${device.id}/chats/${data.chat.id}/labels`
  const newLabels = (data.chat.labels || [])
  for (const label of labels) {
    if (newLabels.includes(label)) {
      newLabels.push(label)
    }
  }
  if (newLabels.length) {
    console.log('[info] update chat labels:', data.chat.id, newLabels)
    await axios.patch(url, newLabels, { headers: { Authorization: config.apiKey } })
  }
}

export async function updateChatMetadata ({ data, device, metadata }) {
  const url = `${API_URL}/chat/${device.id}/contacts/${data.chat.id}/metadata`
  const entries = []
  const contactMetadata = data.chat.contact.metadata
  for (const entry of metadata) {
    if (entry && entry.key && entry.value) {
      const value = typeof entry.value === 'function' ? entry.value() : value
      if (!entry.key || !value || typeof entry.key !== 'string' || typeof value !== 'string') {
        continue
      }
      if (contactMetadata && contactMetadata.some(e => e.key === entry.key && e.value === value)) {
        continue // skip if metadata entry is already present
      }
      entries.push({
        key: entry.key.slice(0, 30).trim(),
        value: value.slice(0, 1000).trim()
      })
    }
  }
  if (entries.length) {
    await axios.patch(url, entries, { headers: { Authorization: config.apiKey } })
  }
}

export async function selectAssignMember (device) {
  const members = await pullMembers(device)

  const isMemberEligible = (member) => {
    if (config.teamBlacklist.length && config.teamBlacklist.includes(member.id)) {
      return false
    }
    if (config.teamWhitelist.length && !config.teamWhitelist.includes(member.id)) {
      return false
    }
    if (config.assignOnlyToOnlineMembers && (member.availability.mode !== 'auto' || ((Date.now() - +new Date(member.lastSeenAt)) > 30 * 60 * 1000))) {
      return false
    }
    if (config.skipTeamRolesFromAssignment && config.skipTeamRolesFromAssignment.some(role => member.role === role)) {
      return false
    }
    return true
  }

  const activeMembers = members.filter(member => member.status === 'active' && isMemberEligible(member))
  if (!activeMembers.length) {
    return console.log('[warning] Unable to assign chat: no eligible team members')
  }

  const targetMember = activeMembers[activeMembers.length * Math.random() | 0]
  return targetMember
}

async function assignChat ({ member, data, device }) {
  const url = `${API_URL}/chat/${device.id}/chats/${data.chat.id}/owner`
  const body = { agent: member.id }
  await axios.patch(url, body, { headers: { Authorization: config.apiKey } })

  if (config.setMetadataOnAssignment && config.setMetadataOnAssignment.length) {
    const metadata = config.setMetadataOnAssignment.filter(entry => entry && entry.key && entry.value).map(({ key, value }) => ({ key, value }))
    await updateChatMetadata({ data, device, metadata })
  }
}

export async function assignChatToAgent ({ data, device }) {
  if (!config.enableMemberChatAssignment) {
    return console.log('[debug] Unable to assign chat: member chat assignment is disabled. Enable it in config.enableMemberChatAssignment = true')
  }
  try {
    const member = await selectAssignMember(device)
    if (member) {
      let updateLabels = []

      // Remove labels before chat assigned, if required
      if (config.removeLabelsAfterAssignment && config.setLabelsOnBotChats && config.setLabelsOnBotChats.length) {
        const labels = (data.chat.labels || []).filter(label => !config.setLabelsOnBotChats.includes(label))
        console.log('[info] remove labels before assiging chat to user', data.chat.id, labels)
        if (labels.length) {
          updateLabels = labels
        }
      }

      // Set labels on chat assignment, if required
      if (config.setLabelsOnUserAssignment && config.setLabelsOnUserAssignment.length) {
        let labels = (data.chat.labels || [])
        if (updateLabels.length) {
          labels = labels.filter(label => !updateLabels.includes(label))
        }
        for (const label of config.setLabelsOnUserAssignment) {
          if (!updateLabels.includes(label)) {
            updateLabels.push(label)
          }
        }
      }

      if (updateLabels.length) {
        console.log('[info] set labels on chat assignment to user', data.chat.id, updateLabels)
        await updateChatLabels({ data, device, labels: updateLabels })
      }

      console.log('[info] automatically assign chat to user:', data.chat.id, member.displayName, member.email)
      await assignChat({ member, data, device })
    } else {
      console.log('[info] Unable to assign chat: no eligible or available team members based on the current configuration:', data.chat.id)
    }
    return member
  } catch (err) {
    console.error('[error] failed to assign chat:', data.id, data.chat.id, err)
  }
}

export async function pullChatMessages ({ data, device }) {
  try {
    const url = `${API_URL}/chat/${device.id}/messages/?chat=${data.chat.id}&limit=25`
    const res = await axios.get(url, { headers: { Authorization: config.apiKey } })
    state[data.chat.id] = res.data.reduce((acc, message) => {
      acc[message.id] = message
      return acc
    }, state[data.chat.id] || {})
    return res.data
  } catch (err) {
    console.error('[error] failed to pull chat messages history:', data.id, data.chat.id, err)
  }
}

// Find an active WhatsApp device connected to the Wassenger API
export async function loadDevice () {
  const url = `${API_URL}/devices`
  const { data } = await axios.get(url, {
    headers: { Authorization: config.apiKey }
  })
  if (config.device && !config.device.includes(' ')) {
    if (/^[a-f0-9]{24}$/i.test(config.device) === false) {
      return exit('Invalid WhatsApp device ID: must be 24 characers hexadecimal value. Get the device ID here: https://app.wassenger.com/number')
    }
    return data.find(device => device.id === config.device)
  }
  return data.find(device => device.status === 'operative')
}

// Function to register a Ngrok tunnel webhook for the chatbot
// Only used in local development mode
export async function registerWebhook (tunnel, device) {
  const webhookUrl = `${tunnel}/webhook`

  const url = `${API_URL}/webhooks`
  const { data: webhooks } = await axios.get(url, {
    headers: { Authorization: config.apiKey }
  })

  const findWebhook = webhook => {
    return (
      webhook.url === webhookUrl &&
      webhook.device === device.id &&
      webhook.status === 'active' &&
      webhook.events.includes('message:in:new')
    )
  }

  // If webhook already exists, return it
  const existing = webhooks.find(findWebhook)
  if (existing) {
    return existing
  }

  for (const webhook of webhooks) {
    // Delete previous ngrok webhooks
    if (webhook.url.includes('ngrok-free.app') || webhook.url.startsWith(tunnel)) {
      const url = `${API_URL}/webhooks/${webhook.id}`
      await axios.delete(url, { headers: { Authorization: config.apiKey } })
    }
  }

  await new Promise(resolve => setTimeout(resolve, 500))
  const data = {
    url: webhookUrl,
    name: 'Chatbot',
    events: ['message:in:new'],
    device: device.id
  }

  const { data: webhook } = await axios.post(url, data, {
    headers: { Authorization: config.apiKey }
  })

  return webhook
}

export function exit (msg, ...args) {
  console.error('[error]', msg, ...args)
  process.exit(1)
}

import ngrok from 'ngrok'
import nodemon from 'nodemon'
import config from './config.js'
import server from './server.js'
import * as actions from './actions.js'
const { exit } = actions

// Function to create a Ngrok tunnel and register the webhook dynamically
async function createTunnel () {
  let retries = 3

  try {
    await ngrok.upgradeConfig({ relocate: false })
  } catch (err) {
    console.error('[warning] Failed to upgrade Ngrok config:', err.message)
  }

  while (retries) {
    retries -= 1
    try {
      const tunnel = await ngrok.connect({
        addr: config.port,
        authtoken: config.ngrokToken,
        path: () => config.ngrokPath || path
      })
      console.log(`Ngrok tunnel created: ${tunnel}`)
      return tunnel
    } catch (err) {
      console.error('[error] Failed to create Ngrok tunnel:', err.message)
      await ngrok.kill()
      await new Promise(resolve => setTimeout(resolve, 1000))
    }
  }

  throw new Error('Failed to create Ngrok tunnel')
}

// Development server using nodemon to restart the bot on file changes
async function devServer () {
  const tunnel = await createTunnel()

  nodemon({
    script: 'bot.js',
    ext: 'js',
    watch: ['*.js', 'src/**/*.js'],
    exec: `WEBHOOK_URL=${tunnel} DEV=false npm run start`,
  }).on('restart', () => {
    console.log('[info] Restarting bot after changes...')
  }).on('quit', () => {
    console.log('[info] Closing bot...')
    ngrok.kill().then(() => process.exit(0))
  })
}

// Initialize chatbot server
async function main () {
  // API key must be provided
  if (!config.apiKey || config.apiKey.length < 60) {
    return exit('Please sign up in Wassenger and obtain your API key:\nhttps://app.wassenger.com/apikeys')
  }

  // OpenAI API key must be provided
  if (!config.openaiKey || config.openaiKey.length < 45) {
    return exit('Missing required OpenAI API key: please sign up for free and obtain your API key:\nhttps://platform.openai.com/account/api-keys')
  }

  // Create dev mode server with Ngrok tunnel and nodemon
  if (process.env.DEV === 'true' && !config.production) {
    return devServer()
  }

  // Find a WhatsApp number connected to the Wassenger API
  const device = await actions.loadDevice()
  if (!device) {
    return exit('No active WhatsApp numbers in your account. Please connect a WhatsApp number in your Wassenger account:\nhttps://app.wassenger.com/create')
  }
  if (device.session.status !== 'online') {
    return exit(`WhatsApp number (${device.alias}) is not online. Please make sure the WhatsApp number in your Wassenger account is properly connected:\nhttps://app.wassenger.com/${device.id}/scan`)
  }
  if (device.billing.subscription.product !== 'io') {
    return exit(`WhatsApp number plan (${device.alias}) does not support inbound messages. Please upgrade the plan here:\nhttps://app.wassenger.com/${device.id}/plan?product=io`)
  }

  // Pre-load device labels and team mebers
  const [members] = await Promise.all([
    actions.pullMembers(device),
    actions.pullLabels(device)
  ])

  // Create labels if they don't exist
  await actions.createLabels(device)

  // Validate whitelisted and blacklisted members exist
  await actions.validateMembers(members)

  server.device = device
  console.log('[info] Using WhatsApp connected number:', device.phone, device.alias, `(ID = ${device.id})`)

  // Start server
  await server.listen(config.port, () => {
    console.log(`Server listening on port ${config.port}`)
  })

  if (config.production) {
    console.log('[info] Validating webhook endpoint...')
    if (!config.webhookUrl) {
      return exit('Missing required environment variable: WEBHOOK_URL must be present in production mode')
    }
    const webhook = await actions.registerWebhook(config.webhookUrl, device)
    if (!webhook) {
      return exit(`Missing webhook active endpoint in production mode: please create a webhook endpoint that points to the chatbot server:\nhttps://app.wassenger.com/${device.id}/webhooks`)
    }
    console.log('[info] Using webhook endpoint in production mode:', webhook.url)
  } else {
    console.log('[info] Registering webhook tunnel...')
    const tunnel = config.webhookUrl || await createTunnel()
    const webhook = await actions.registerWebhook(tunnel, device)
    if (!webhook) {
      console.error('Failed to connect webhook. Please try again.')
      await ngrok.kill()
      return process.exit(1)
    }
  }

  console.log('[info] Chatbot server ready and waiting for messages!')
}

main().catch(err => {
  exit('Failed to start chatbot server:', err)
})
import express from 'express'
import bodyParser from 'body-parser'
import * as bot from './bot.js'
import * as actions from './actions.js'

// Create web server
const app = express()

// Middleware to parse incoming request bodies
app.use(bodyParser.json())

// Index route
app.get('/', (req, res) => {
  res.send({
    name: 'chatbot',
    description: 'WhatsApp ChatGPT powered chatbot for Wassenger',
    endpoints: {
      webhook: {
        path: '/webhook',
        method: 'POST'
      },
      sendMessage: {
        path: '/message',
        method: 'POST'
      },
      sample: {
        path: '/sample',
        method: 'GET'
      }
    }
  })
})

// POST route to handle incoming webhook messages
app.post('/webhook', (req, res) => {
  const { body } = req
  if (!body || !body.event || !body.data) {
    return res.status(400).send({ message: 'Invalid payload body' })
  }
  if (body.event !== 'message:in:new') {
    return res.status(202).send({ message: 'Ignore webhook event: only message:in:new is accepted' })
  }

  res.send({ ok: true })

  // Process message in background
  bot.processMessage(body).catch(err => {
    console.error('[error] failed to process inbound message:', body.id, body.data.fromNumber, body.data.body, err)
  })
})

// Send message on demand
app.post('/message', (req, res) => {
  const { body } = req
  if (!body || !body.phone || !body.message) {
    return res.status(400).send({ message: 'Invalid payload body' })
  }

  actions.sendMessage(body).then((data) => {
    res.send(data)
  }).catch(err => {
    res.status(+err.status || 500).send(err.response ? err.response.data : {
      message: 'Failed to send message'
    })
  })
})

// Send a sample message to your own number, or to a number specified in the query string
app.get('/sample', (req, res) => {
  const { phone, message } = req.query
  const data = {
    phone: phone || app.device.phone,
    message: message || 'Hello World from Wassenger!',
    device: app.device.id
  }
  actions.sendMessage(data).then((data) => {
    res.send(data)
  }).catch(err => {
    res.status(+err.status || 500).send(err.response ? err.response.data : {
      message: 'Failed to send sample message'
    })
  })
})

app.use((err, req, res, next) => {
  res.status(+err.status || 500).send({
    message: `Unexpected error: ${err.message}`
  })
})

export default app
// Cache time-to-live in milliseconds
export const cacheTTL = 10 * 60 * 1000

// In-memory cache store
export const cache = {}

// In-memory store for a simple state machine per chat
// You can use a database instead for persistence
export const state = {}
{
  "name": "whatsapp-chatgpt-bot-demo",
  "version": "1.0.0",
  "private": true,
  "license": "MIT",
  "engine": {
    "node": ">=16"
  },
  "type": "module",
  "scripts": {
    "start": "node main.js",
    "dev": "DEV=true npm run start",
    "lint": "./node_modules/.bin/standard ."
  },
  "dependencies": {
    "axios": "^1.3.6",
    "express": "^4.18.2",
    "ngrok": "^5.0.0-beta.2",
    "nodemon": "^2.0.22",
    "openai": "^4.14.2"
  },
  "devDependencies": {
    "standard": "^17.1.0"
  }
}

Questions

Can I train the AI to behave in a customized way?

Yes! You can provide customized instructions to the AI to determine the bot behavior, identity and more.

To set your instructions, enter the text in config.js > botInstructions.

Can I instruct the AI not to reply about unrelated topics?

Yes! By defining a set of clear and explicit instructions, you can teach the AI to stick to the role and politely do not answer to topics that are unrelated to the relevant topic.

For instance, you can add the following in your instruction:

You are a smart virtual customer support assistant who works for Wassenger.
Be polite, be gentle, be helpful and emphatic.
Politely reject any queries that are not related to your customer support role or Wassenger itself.
Strictly stick to your role as customer support virtual assistant for Wassenger.

Can I customize the chatbot response and behavior?

For sure! The code is available for free and you can adapt it as much as you need.

You just need to have some JavaScript/Node.js knowledge, and you can always ask ChatGPT to help you write the code you need.

How to stop the bot from replying to certain chats?

You should simply assign the chat(s) to any agent on the Wassenger web chat or using the API.

Alternatively, you can set blacklisted labels in the config.js > skipChatWithLabels field, then add one or these labels to the specific chat you want to be ignored by the bot. You can assign labels to chats using the Wassenger web chat or using the API.

Do I have to use Ngrok?

No, you don't. Ngrok is only used for development/testing purposes when running the program from your local computer. If you run the program in a cloud server, most likely you won't need Ngrok if your server can be reachable via Internet using a public domain (e.g: bot.company.com) or a public IP.

In that case, you simply need to provide your server full URL ended with /webhook like this when running the bot program:

WEBHOOK_URL=https://bot.company.com:8080/webhook node main

Note: https://bot.company.com:8080 must point to the bot program itself running in your server and it must be network reachable using HTTPS for secure connection.

What happens if the program fails?

Please check the error in the terminal and make sure your are running the program with enough permissions to start it in port 8080 in localhost.

How to avoid certain chats being replied by the bot?

By default the bot will ignore messages sent in group chats, blocked and archived chats/contacts.

Besides that, you can blacklist or whitelist specific phone numbers and chat with labels that be handled by the bot.

See numbersBlacklist, numbersWhitelist, and skipChatWithLabels options in config.js for more information.

Can I run this bot on my server?

Absolutely! Just deploy or transfer the program source code to your server and run the start command from there. The requirements are the same, no matter where you run the bot.

Also remember to define the WEBHOOK_URL environment variable with your server Internet accessible public URL as explained before.


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