(The blog previously written for “How to make SUSI AI Line Bot” is no longer valid as a lot has changed since then. SUSI API, LINE developer menu etc has changed. This blog post describes the updated procedure for creating SUSI AI LINE Bot. The previous blog can be found here – https://blog.fossasia.org/how-to-make-susi-ai-line-bot/)

Susi AI is an intelligent Open Source personal assistant. SUSI AI Bots are built to enable users to chat with SUSI on different clients.

Pre-requisites –

1. In order to integrate SUSI’s API with Line bot, you will need to have a Line account first.

Download LINE Messenger app from here –

Google Play Store

Apple App Store

2. GitHub Account

Create a GitHub from here – Sign up on GitHub

3. Heroku Account

To create Heroku account, go to Heroku and click on Sign Up.

4. Node.js

Install Node.js from https://nodejs.org/en/ if it isn’t installed already on your computer.

To check if node is already installed or not, open terminal and type the command –

node -v

If you see something like this – (version can be different)

v9.4.0

Then Node.js is installed on your computer and you can follow along.

Procedure:

Now that you have created a LINE account, GitHub account, Heroku account and installed Node.js, we can move to the creating the SUSI AI bot.

You can either deploy susi_linebot repository to create SUSI AI LINE bot or you can create a new repository on your account then deploy it to Heroku. The next section will describe how to create a new repository for deploying SUSI AI Line bot. If you want to just deploy susi_linebot then skip the next section.

Creating the SUSI AI LINE bot codebase:

1. Create a folder on your computer with any name. Open terminal and change your current directory to the new folder you just created.

2. Type npm init command and enter details like name, version etc. (preferably just keep pressing enter key and let the values stay default)

3. Create a file with the same name that you wrote in entry point (index.js by default). NOTE – It should be in the same folder that you created earlier.

4. Type the following commands in command line –

npm i -s @line/bot-sdk

npm i -s express

npm i -s request

5. Open package.json file. It should look like this:

{
  "name": "susi_linebot",
  "version": "1.0.0",
  "description": "SUSI AI LINE bot",
  "main": "index.js",
  "scripts": {
    "start": "node index.js",
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "@line/bot-sdk": "^6.0.1",
    "express": "^4.16.3",
    "request": "^2.85.0"
  }
}

You should see “@line/bot-sdk”, “express” and “request” under dependencies. Versions can change. Make sure to add “start” under scripts or else deploying on Heroku will cause an error.

6. Copy the following code into the file that you created i.e. index.js

'use strict';
const line = require('@line/bot-sdk');
const express = require('express');
var request = require("request");

// create LINE SDK config from env variables
const config = {
   channelAccessToken: process.env.CHANNEL_ACCESS_TOKEN,
   channelSecret: process.env.CHANNEL_SECRET,
};

// create LINE SDK client
const client = new line.Client(config);

// create Express app
// about Express: https://expressjs.com/
const app = express();

// register a webhook handler with middleware
app.post('/webhook', line.middleware(config), (req, res) => {
   Promise
       .all(req.body.events.map(handleEvent))
       .then((result) => res.json(result))
       .catch((err) => {
        console.error(err);
        res.status(500).end();
      });
});

// event handler
function handleEvent(event) {
   if (event.type !== 'message' || event.message.type !== 'text') {
       // ignore non-text-message event
       return Promise.resolve(null);
   }
   var options = {
       method: 'GET',
       url: 'https://api.susi.ai/susi/chat.json',
       qs: {
           timezoneOffset: '-330',
           q: event.message.text
       }
   };
   request(options, function(error, response, body) {
       if (error) throw new Error(error);
       // answer fetched from susi
       var ans = (JSON.parse(body)).answers[0].actions[0].expression;
       // create a echoing text message
       const answer = {
           type: 'text',
           text: ans
       };
       // use reply API
       return client.replyMessage(event.replyToken, answer);
   })
}

// listen on port

const port = process.env.PORT || 3000;
app.listen(port, () => {
   console.log(`listening on ${port}`);
});

7. In order to deploy this bot on Heroku, we have to make a github repository for it. For making a github repository for the chatbot, follow these steps:

In the command line, change current directory to the folder we created above for the bot and type in the following commands.

git init
git add .
git commit -m "initial"

Now, you have to create a Github repository, follow these steps to do that –

1. Go to https://github.com/ and login.
2. Create a new repository. Choose any name.
3. Get the URL for remote repository and copy it.

Again go to the command line, change current directory to the folder we created above for the bot and type in the following commands.

git remote add origin <URL for remote repository that you just copied>
git remote -v
git push -u origin master

Creating SUSI AI bot on LINE:

1. Go to LINE Developers and click on “Start using Messaging API”.

2. Login through the email ID you used for creating LINE account on LINE app. (If you didn’t enter an email address while creating LINE account then go to “Settings” on LINE app and click on “Account”. Now enter an email address.)

3. Now you have to create a new channel. For that, first of all select a provider or create a new one. You can name it anything.

4. Enter the information for Messaging API. Write all details like App name, description etc. Choose “Developer Trial” under Plan option.

5. Choose any category, subcategory, type in your email address and click Confirm.

6. Now click on your channel to open channel settings.

7. Under “Messaging settings”, click on Issue to issue a channel access token. Choose any number of hours and then issue it. Copy it and save it somewhere. We’ll need it later on.

8. Copy Channel secret given on the same page.

Deploying the Bot on Heroku:

1. Go to Heroku and login.

2. Go to dashboard and create a new app.

3. After creating an app, go to Deploy and choose “GitHub” for Deployment method.

4. Search the repository that you created on GitHub or select susi_linebot after forking it and connect to it in “App connected to GitHub”.

5. Enable Automatic deployment.

6. Now go to Settings and setup Config Variables.

Add the channel access token which you copied earlier as value of “CHANNEL_ACCESS_TOKEN” and the channel secret as value of “CHANNEL_SECRET”. After saving, click on Hide Config Vars.

Now, your bot is deployed on Heroku.

Final Steps:

Finally, go back to LINE Developers website. In settings of SUSI AI app, under “Messaging settings”, enable webhooks and add webhook URL. It will look like this:

https://<your_heroku_app_name>.herokuapp.com/webhook

Clicking on “verify” should show success as shown.

Congratulations! Your SUSI AI LINE bot is ready! Add it as a friend by scanning the QR code provided in the same settings menu and start chatting with SUSI.

References:

• LINE Messaging API documentation – https://developers.line.me/en/docs/messaging-api/overview/
• Node.js SDK for LINE Messaging API – https://github.com/line/line-bot-sdk-nodejs
• Previous blog on fossasia for making SUSI AI LINE bot (outdated) – https://blog.fossasia.org/how-to-make-susi-ai-line-bot/
• LINE Messenger logo above heading – https://www.freepnglogos.com/logos/line-logo-messenger-png