In order to integrate SUSI’s API with Line bot you will need to have a line account first so that you can follow below procedure. You can download app from here.

Pre-requisites:

• Line app
• Github
• Heroku
  
  Steps:

1. 1. Install Node.js from the link below on your computer if you haven’t installed it already https://nodejs.org/en/.
   2. Create a folder with any name and open shell and change your current directory to the new folder you created.
   3. Type npm init in command line and enter details like name, version and entry point.
   4. Create a file with the same name that you wrote in entry point in above given step. i.e index.js and it should be in same folder you created.
   5. Type following commands in command line  npm install –save @line/bot-sdk. After bot-sdk is installed type npm install –save express after express is installed type npm install –save request when all the modules are installed check your package.json modules will be included within dependencies portion.
      
      Your package.json file should look like this.

      {
      "name": "SUSI-Bot",
      "version": "1.0.0",
      "description": "SUSI AI LINE bot",
      "main": "index.js",
      "dependencies": {
         "@line/bot-sdk": "^1.0.0",
         "express": "^4.15.2",
         "request": "^2.81.0"
      },
      "scripts": {
         "start": "node index.js"
       }
      }

   6. Copy following code into file 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));
      });
      
      // event handler
      
      function handleEvent(event) {
         if (event.type !== 'message' || event.message.type !== 'text') {
             // ignore non-text-message event
             return Promise.resolve(null);
         }
      
         var options1 = {
             method: 'GET',
             url: 'http://api.asksusi.com/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
             //console.log(body);
             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. Now we have to get channel access token and channel secret to get that follow below steps.
      
      
   8. If you have Line account then move to next step else sign up for an account and make one.
   9. Create Line account on  Line Business Center with messaging API and follow these steps:
   10. In the Line Business Center, select Messaging API under the Service category at the top of the page.
   11. Select start using messaging API, enter required information and confirm it.
   12. Click LINE@ Manager option, In settings go to bot settings and Enable messaging API
   13. Now we have to configure settings. Allow messages using webhook and select allow for “Use Webhooks”.
   14. Go to Accounts option at top of page and open LINE Developers.
   15. To get Channel access token for accessing API, click ISSUE for the “Channel access token” item.
   16. Click EDIT and set a webhook URL for your Channel. To get webhook url deploy your bot to heroku and see below steps.
   17. Before deploying we have to make a github repository for chatbot to make github repository follow these steps:
       
       In command line change current directory to folder we created above and  write
       
       

       git init
       git add .
       git commit -m”initial”
       git remote add origin <URL for remote repository> 
       git remote -v
       git push -u origin master 

       You will get URL for remote repository by making repository on your github and copying this link of your repository.

       

   18. To deploy your bot to heroku you need an account on Heroku and after making an account make an app.
   19. Deploy app using github deployment method.
       
       
       
   20. Select Automatic deployment method.
       
       
       
   21. After making app copy this link and paste it in webhook url in Line channel console page from where we got channel access token.
       
                 https://<your_heroku_app_name>.herokuapp.com/webhook
       
   22. Your SUSI AI Line bot is ready add this account as a friend and start chatting with SUSI.
       Here is the LINE API reference https://devdocs.line.me/en/