Using CoreLocation in SUSI iOS

The SUSI Server responds with intelligent answers to the user’s queries. To make these answers better, the server makes use of the user’s location which is sent as a parameter to the query request each time. To implement this feature in the SUSI iOS client, we use the CoreLocation framework provided by Apple which helps us to get the user’s location coordinates and add them as a parameter to each request made.

In order to start with using the CoreLocation framework, we first import it inside the view controller.

import CoreLocation

Now, we create a variable of type CLLocationManager which will help us to use the actual functionality.

// Location Manager
var locationManager = CLLocationManager()

The location manager has some delegate methods which give an option to get the maximum accuracy for a user’s location.  To set that, we need the controller to conform to the CLLocationManagerDelegate, so we create an extension of the view controller conforming to this.

extension MainViewController: CLLocationManagerDelegate {

   // use functionality


Next, we set the manager delegate.

locationManager.delegate = self

And create a method to ask for using the user’s location and set the delegate properties.

func configureLocationManager() {
       locationManager.delegate = self
       if CLLocationManager.authorizationStatus() == .notDetermined || CLLocationManager.authorizationStatus() == .denied {

       locationManager.distanceFilter = kCLDistanceFilterNone
       locationManager.desiredAccuracy = kCLLocationAccuracyBest

Here, we ask for the user location if it was previously denied or is not yet determined and following that, we set the `distanceFilter` as kCLDistanceFilterNone  and `desiredAccuray` as kCLLocationAccuracyBest.. Finally, we are left with starting to update the location which we do by:


We call this method inside viewDidLoad to start updation of the location when the view first loads. The complete extension looks like below:

extension MainViewController: CLLocationManagerDelegate {

   // Configures Location Manager
   func configureLocationManager() {
       locationManager.delegate = self
       if CLLocationManager.authorizationStatus() == .notDetermined || CLLocationManager.authorizationStatus() == .denied {

       locationManager.distanceFilter = kCLDistanceFilterNone
       locationManager.desiredAccuracy = kCLLocationAccuracyBest


Now, it’s very easy to use the location manager and get the coordinates and add it to the params for each request.

if let location = locationManager.location {
   params[Client.ChatKeys.Latitude] = location.coordinate.latitude as AnyObject
   params[Client.ChatKeys.Longitude] = location.coordinate.longitude as AnyObject

Now the params which is a dictionary object is added to each request made so that the user get’s the most accurate results for each query he makes.


Using Vector Images in SUSI Android

SUSI is an artificial intelligence for interactive chat bots. For making it more user friendly and interactive we add a lot of images in the form of drawable resources in the SUSI Android App ( Most of these drawables are in the form of PNGs. There are certain problems associated with the use of PNG images.

  1. PNGs cannot be scaled without losing quality. Due to which for the same PNG image we have to include separate images of varied quality. Otherwise the image will become blur.
  2. PNGs tends to take large disk space which can be easily reduced with the use of vector images.
  3. PNGs have fixed color and dimensions which cannot be changed.

Due to the above shortcomings of PNG images we decided to use vector drawable images instead of them.

Advantages associated with Vector images

  1. They can be scaled to any size without the loss in quality. Thus we need to include only a single image in the app and not of varied qualities.
  2. They are very small in size as compared to PNGs.
  3. They can be easily modified programmatically in XML file unlike PNGs.

Using Vector Images in Android Studio

Android Studio provide tools by which we can directly import vector drawables in the project. To import Vector images go to File>New>Vector Assets in studio.

From here we can choose the icon we want to include in our project and click OK. The icon will appear in the drawables directory and can be used anywhere in the projects.

Implementation in SUSI Android

In Susi Android we have used various vector images such as arrows, pointer and even the logo of the app. Here below is the logo of SUSI.

This is actually a vector image below we will see the code required to get this logo as the output.

<vector android:height="50dp" android:viewportHeight="279.37604"

  android:viewportWidth="1365.2" android:width="220dp" xmlns:android="">

<path android:fillColor="#ffffff"

      android:pathData="M127.5,7.7c-26.8,3.3 -54.2,16.8 -75.9,37.4 -11.8,11.1 -20.4,22.9 -28.1,38.4 -8.9,17.8 -12.8,32.1 -13.7,51l-0.3,6 39,0 39,0 0.3,-4c0.7,-12.1 6.8,-24.1 17.2,-34.5 8.5,-8.4 16.2,-13.4 25.9,-16.7l6.6,-2.2 81.3,-0.1 81.2,0 0,-38 0,-38 -84.7,0.1c-46.7,0.1 -86.1,0.4 -87.8,0.6z" android:strokeColor="#00000000"/>

  <path android:fillColor="#ffffff"

      android:pathData="M319.2,11.3l-4.3,4.3 0.3,103c0.4,113.2 0,105.9 6.4,118.6 10.8,21.3 35.1,41.9 56.2,47.3 8.5,2.3 99.1,2.2 107.7,0 18.7,-4.9 39.2,-20.7 51.5,-39.7 3.4,-5.1 7.1,-12.2 8.3,-15.8l2.2,-6.5 0.5,-103.3 0.5,-103.3 -4.5,-4.4 -4.6,-4.5 -31.5,0 -31.5,0 -4.7,4.8 -4.7,4.8 0,93 0,93 -3.3,3.2 -3.3,3.2 -29,0 -29,0 -2.6,-2.7 -2.7,-2.8 -0.7,-94.2 -0.7,-94.2 -4.3,-4 -4.2,-4.1 -31.9,0 -31.9,0 -4.2,4.3z" android:strokeColor="#00000000"/>

  <path android:fillColor="#ffffff"

      android:pathData="M680,7.6c-31.6,4.8 -56.1,17.3 -79,40.3 -23.2,23.3 -36.3,50.5 -38.9,80.9 -0.5,5.9 -0.7,11 -0.4,11.4 0.2,0.5 17.7,0.8 38.8,0.8l38.4,0 0.6,-4.8c3.2,-23.2 21.3,-44.1 44.7,-51.3 5.6,-1.8 10.6,-1.9 86.6,-1.9l80.7,0 -0.3,-38 -0.2,-38 -84.3,0.1c-46.3,0.1 -85.3,0.3 -86.7,0.5z" android:strokeColor="#00000000"/>

  <path android:fillColor="#ffffff"

      android:pathData="M869.1,13.4l-4.1,6.4 0,126.4 0,126.3 4.8,6.7 4.7,6.8 31.6,0 31.6,0 4.7,-7 4.6,-7 0,-125.7 0,-125.8 -4.7,-6.7 -4.8,-6.8 -32.1,0 -32.1,0 -4.2,6.4z" android:strokeColor="#00000000"/>

  <path android:fillColor="#ffffff"

      android:pathData="M222.5,152.2c-0.2,0.7 -0.9,4.2 -1.5,7.7 -3.4,19.5 -19.4,38 -40,46.4l-5.5,2.2 -83,0.5 -83,0.5 -0.3,37.8 -0.2,37.8 89.2,-0.3 89.3,-0.3 9.6,-2.7c57.7,-16.3 100.1,-67.4 102.1,-123.3l0.3,-7 -38.3,-0.3c-30.1,-0.2 -38.3,0 -38.7,1z" android:strokeColor="#00000000"/>

  <path android:fillColor="#ffffff"

      android:pathData="M774.5,152.2c-0.2,0.7 -0.9,4.1 -1.5,7.5 -3.3,19.2 -18.8,37.3 -39.4,46.2l-6.1,2.6 -83,0.5 -83,0.5 -0.3,37.7 -0.2,37.8 85.9,0c93.7,0 91.4,0.1 110.1,-5.9 26.4,-8.5 53.3,-28.4 69.8,-51.7 15.2,-21.3 25.1,-50.1 24,-69.9l-0.3,-6 -37.8,-0.3c-29.7,-0.2 -37.8,0 -38.2,1z" android:strokeColor="#00000000"/>

  <path android:fillColor="#ffffff" android:pathData="m1146.99,0 l-1.38,1.19c-0.76,0.66 -1.85,1.61 -2.43,2.13 -0.58,0.51 -1.75,1.54 -2.61,2.28 -1.52,1.31 -1.58,1.41 -2.4,3.53 -0.46,1.2 -0.92,2.37 -1.01,2.59 -30.55,82.93 -61.62,165.72 -96.03,259.63 0,0.08 1.61,1.88 3.57,3.98l3.57,3.84 33.47,-0.04 33.47,-0.04c12.28,-35.6 25.13,-72.47 37.4,-107.27 0.06,-0.25 0.28,-0.64 0.5,-0.88 0.37,-0.41 0.61,-0.43 4.2,-0.43 3.63,0 3.83,0.02"/>

  <path android:fillColor="#ffffff" android:pathData="m967.09,279.18c-2.48,-3.74 -4.97,-7.04 -8.09,-11.76l0.09,-43.92c3.34,-5.26 5.31,-6.73 8.42,-11.51 17.91,0.02 34.3,0.26 50.88,0.26 3.21,4.88 4.09,6.72 7.81,12.66 -0.05,13.98 0.1,27.96 -0.12,41.94 -2.9,4.2 -4.27,7.42 -7.78,12.18 -18.81,-0.04 -35.43,0.2 -51.21,0.15z"/>

  <path android:fillColor="#ffffff"

      android:pathData="m1287.3,6.59 l-4.1,6.4 0,126.4 0,126.3 4.8,6.7 4.7,6.8 31.6,0 31.6,0 4.7,-7 4.6,-7 0,-125.7 0,-125.8 -4.7,-6.7 -4.8,-6.8 -32.1,0 -32.1,0 -4.2,6.4z" android:strokeColor="#00000000"/>


In this code we can easily change the color and minor details for the logo which could have been not possible if the logo was in PNG format. Also we don’t need multiple logo images of varied qualities as it can be scaled without decreasing quality.


Detecting password strength in SUSI.AI Web Chat SignUp

Every SignUp page contains a field to enter a password, but it should not be just a dumb component that takes input and saves it on server. A password field on a SignUp page should tell how weak or strong the password is. We decided to implement this in our SUSI.AI Web Chat SignUp Page.

Our SignUp page look like this:

After entering a valid email, user needs to enter the password. It shows that minimum 6 character are required:

We have the following div for our Password Field :

  floatingLabelText="Password" />

In our OnChange Method we need to check the strength of password once the six character limit is crossed and display the strength visually.

We have used Dropbox’s zxcvbn library for the purpose of getting the strength of password.

Major reasons of choosing this library are :

  • Flexibility : It allows different passwords as long as certain level of complexity is matched.
  • Usability : It is very easy use and gives instant feedback. This helps user towards less guessable passwords.

For installing this library :

 npm -S install zxcvbn

For importing this:

import zxcvbn from 'zxcvbn';

Now in our OnChange Method:

handleChange = (event) => {
        let email;
        let password;
        let confirmPassword;
        let serverUrl;
        let state = this.state
      // Checking if event is password
        if ( === 'password') {
            password =;
            let validPassword = password.length >= 6;
            state.passwordError = !(password && validPassword);
            if(validPassword) {
              //getting strength of password from zxcvbn
              let result = zxcvbn(password);
              let strength = [
            else {


In the above method result variable gets the strength of password and result.score gives us the score of password in terms of an integer and according to which we have made an array to get result in remarks corresponding to score. We have remarks like Good, Strong, etc.

Initially we have set the score to -1 to know that user has not entered the password yet. Once user has entered password the score changes.
Then we made a wrapper class to help css format the color of remark and display a meter (determining password strength) with corresponding length and color. We have used template strings to make our wrapper class. This helps us in having different names of wrapper class according to the score of the password.

// using Template Strings(look at resources for more info)
const PasswordClass=[`is-strength-${this.state.passwordScore}`];

Then we wrapped our Password field in div with className = “PasswordClass”.

<div className={PasswordClass.join(' ')}>
            floatingLabelText="Password" />
            <div className="ReactPasswordStrength-strength-bar" />

All that was left to was add css code corresponding to every score. For example for score=3, the following css was made:

.is-strength-3 { color: #57B8FF; }

.ReactPasswordStrength-strength-bar {
  box-sizing: border-box;
  height: 2px;
  position: relative; top: 1px; right: 1px;
  transition: width 300ms ease-out;

.is-strength--1 .ReactPasswordStrength-strength-bar {
  background: #D1462F;
  display: none;
// if strength = -1 then setting display of block equals to none
.is-strength--1 .ReactPasswordStrength-strength-bar {
  background: #D1462F;
  display: none;

.is-strength-3 .ReactPasswordStrength-strength-bar {
  background: #57B8FF; //Changing color according to password’s strength
  width: 192px; //Changing width according to password’s strength
  display: block;

After successfully implementing all these features, We had following SignUP page:


1)Dropbox’s library(ZXVBN):

2)Template Strings(Used here for making wrapping class of Password Field):

Test Link:

This can be tested here.

Adding Emoji Support in SUSI Web Chat

SUSI.AI web chat sometimes, renders responses which contains emojis. We cannot rely on browser’s capability to render these emojis. The Problem is, that the default support for emojis of browsers does not offer a great variety of emojis to be rendered. The solution we implemented in the SUSI.AI web chat is to make use of a npm package to support our need for displaying emojis.

There were many options to choose from. For example :

Comparison between emoji packages :

Property Twemoji React-easy-emoji React-twemoji React-emojione
Built by Twitter Appfigures ZxMYS Pladaria
Usage Can be used as an object with function parse: twemoji.parse() Can be used as function: emoji() It is a simple wrapper for Twemoji.Can be used as component: <Twemoji> Can be used as function: emojify() or component: <Emojify>
Conversion compatibility Provides standard Unicode emoji support across all platforms Parse only basic emojis.Doesn’t parse emoji names like 🙂 and emoticons like 🙂 Convert emoji characters to Twemoji images Converts shortnames, unicode and ASCII smileys into renderable emojis
Dependencies None loot-web-kit lodash, prop-types, twemoji None

After detailed analysis of the above mentioned packages, we decided to go with React-emojione.

The major reasons are :

  • It is very easy to use.
  • It has no dependencies.
  • It can convert shortnames, unicode and ASCII symbols properly.
  • It can be used as both function and component, which diversifies its usage.


npm install -S react-emojione

Basic usage (as function)

import {emojify} from 'react-emojione';

Basic usage (as component)

import Emojify from 'react-emojione';

Some notes about the <Emojify> component:

  • If it has a single child, it won’t be wrapped
  • Otherwise it will be wrapped with a <span>

Difference between component and function?

Functional Stateless Components are just a ‘dumb’ function that takes props as an input. They do not have any state or methods. Just (props) => { return <span>content</span>; }

Class components can have state, variables, methods etc.

Now we needed our react app to render emojis. Our component named MessageListItem.react renders all the text and images of response.

There is a function called imageParse in this component. We use this function to parse our emojis.

Screenshot of SUSI Web Chat

Emoji’s like (:p) are now rendered properly

The implementation is as follows :

function imageParse(stringWithLinks){
  let replacePattern = new RegExp([
  let splits = stringWithLinks.split(replacePattern);
  let result = [];
    let checkmatch = item.match(replacePattern);
        <img key={key} src={checkmatch}
            style={{width:'95%',height:'auto'}} alt=''/>)
      result.push(<Emojify  key={key}>{item}</Emojify>);
  return result;

Here we put {item} inside <Emojify> tag to render all the emoji’s present inside {item}.

This parses all emojis regardless of browser support. This package fulfills all our needs in this case.


react-emojione package:

Testing link: SUSI.AI (Web Chat):

Adding Snackbar to undo recent change in theme of SUSI.AI Web Chat

SUSI.AI Web Chat has two primary themes: Light and Dark. The user can switch between these two from settings, but what if the user does not prefer the theme change. He/She has to repeat the entire process of Going to Settings -> Selecting another theme -> saving it. To enable the user to instantly change the theme, we decided to add snackbar on theme change.

What is Snackbar ?

Snackbar contains info regarding the operation just performed and it displays them in a visual format. Snackbar can also have a button like “Undo” to revert the recent operation just made.

It appears at the bottom of screen by default. A simple snackbar looks like this:

Now we needed this to pop-up, whenever the theme is changed. When a user changes theme we run a function named “implementSettings” which checks what the theme is changed to.

The method is:

implementSettings = (values) => {
    this.setState({showSettings: false});
      this.setState({SnackbarOpen: true});
    setTimeout(() => {
           SnackbarOpen: false
   }, 2500);

The argument values is an object that contains all the change that user has made in settings. Here values.theme contains the value of theme user selected from settings. We first check if the theme is same as the current one if so, we do nothing. If the theme is different from current, then we update the theme by calling this.changeTheme(values.theme) and also initiate snackbar by setting SnackbarOpen to open.

The snackbar component looks like:

     message={'Theme Changed'}

This appears on the screen as follows :

Now if a user wants to change the theme instantly he/she can press the undo button. For this undo button, we have a method handleActionTouchTap. In this method, we change the theme back to previous one. The method is implemented in the following manner:

handleActionTouchTap = () => {
      SnackbarOpen: false,
      case 'light': {
      case 'dark': {
      default: {
          // do nothing

The above method is pretty self-explanatory which checks the current theme(“light” or “dark”) and then revert it. We also change the state of SnackbarOpen to “false” so that on clicking “UNDO” button, the theme changes back to previous one and the snackbar closes.Now user is having an option of instantly changing back to previous theme.


Testing Link:

Using Day Night Theme in SUSI Android

SUSI is an artificial intelligence for interactive chat bots. It provides response to the user in most intuitive way. Therefore we thought why not implement the option to give theme preference to the user to make it more interactive. It will also help in increasing the user’s interest towards the application.

We tried out different themes and then finally decided to settle for the newly announced Day Night Theme for the SUSI Android App ( This theme is provided by AppCompat 23.2.0 . With the help of this theme we can switch between Theme.AppCompat.Light (light) and Theme.AppCompat (dark) based on the user preference and time of day. For default the theme is set to the light theme and it can be easily changed from the settings. Thus it allows the user to change the theme according to his or her mood which looks very intuitive.

How to use this theme?

To use the Day Night theme is quite simple. We just need to extend our default theme to that of Theme.AppCompat.DayNight. The declaration is done as shown below in the screenshot.

<style name="MyTheme" parent="Theme.AppCompat.DayNight">

  <!-- Blah blah -->


Now to enable different features of the theme in our application we need to call AppCompatDelegate.setDefaultNightMode(). It takes one of the following values as the parameter.

  • MODE_NIGHT_NO. This is for the day (light) theme.
  • MODE_NIGHT_YES.This is for the night (dark) theme.
  • MODE_NIGHT_AUTO. It automatically changes between the above two themes based on the time of day.
  • MODE_NIGHT_FOLLOW_SYSTEM (default). This theme is dependent on the system settings of the user mobile phone.

We can set one of these parameters at the time of calling the function to fix the theme of the application in the following way.

static {




The theme inside an activity is set at the time time of calling onCreate() method. Therefore we cannot change the theme from any other place inside our activity apart from onCreate(). If we want to set it inside our activity but outside the onCreate() method then we have to call the recreate() function to recreate the whole activity which will implement the selected theme.Let us look at the example.

public class MyActivity extends AppCompatActivity {

 public void onCreate(Bundle savedInstanceState) {


      if (savedInstanceState == null) {

          // Set the local night mode to some value



          // Now recreate for it to take effect





To take care of the text colors in our app we can set textColor attribute as


Now let us look at the implementation in Susi Android

In Susi Android we are providing user the option to select either the dark or the light theme in the settings.

The code for the implementation is as below


protected void onCreate(Bundle savedInstanceState) {


  prefs = getSharedPreferences(Constant.THEME, MODE_PRIVATE);

  if(prefs.getString(Constant.THEME,"Dark").equals("Dark")) {



  else {





The result output for the light theme is

To learn more about themes in Android you can refer to this link.


React Routes to Deploy 404 page on gh-pages and surge

Web applications need 404 page to handle broken urls. If we can have a productive 404 page we can keep users with our application. This is how we made 404 page to SUSI.AI web chat application.
React routes ?
We use react routes to navigate throughout the application.we have to define which page to go from each and every route. If user is trying to go to broken Link application should show 404 page.
In the SUSI Web Chat application we have setuped routes in index.js file which is on the root of the application.

<Router history={hashHistory}>
                <Route exact path="/" component={ChatApp} />
                <Route exact path="/signup" component={SignUp} />
                <Route exact path="/logout" component={Logout} />
                <Route exact path="/forgotpwd" component={ForgotPassword} />
                <Route exact path="*" component={NotFound} />


“<Route exact path=”*” component={NotFound} />”  This line defines the 404 page route . this should be defined after all other routes. Because application should first search for defined routes.If the requested route is not defined, Application should show the 404 route.
To use these JSX elements we have to import this dependency on top of the index.js

import {
    BrowserRouter as Router,
} from 'react-router-dom';


After you define like this It will work correctly on your localhost after you deployed it on gh-pages or surge it will not be work there as we wish.
When we try to access URL directly or when we try to access wrong URL it will redirect to default github 404 page.

After we built our application we get static index.html file and another set of files.when we try to access it will load index.html file. If we access another url it will automatically loads default github pages 404 page.
So we can do a little hack for use direct URLs like this .
We can add same copy of index.html file as 404.html then user tries to go to different URL instead of It loads our 404.html file since it contains all other routes it redirects to the correct route.if there is no matching route it shows our 404 page instead of default github pages 404 page.
Since all our deployment tasks are handle by we have to add this actions into file like this.

rm -rf node_modules/	 
mv ../build/* .
cp index.html 404.html   <--- this part


Then it will create 404.html file with the content of index.html file after each and every commit.
If you need to do the same thing on (we use surge for show previews of every PR ) we have to add a copy of index.html file as 200.html .
You can do this after you run the

npm run deploy


Just before giving the deployment URL you need to create a copy of index.html file on build folder and it should be renamed as 200.html and it will work as we wish. This is all for today.


  • Read More – Adding a 200 page for client-side routing :

How to Make SUSI AI Slack Bot

To make SUSI slack bot we will use real time messaging api of slack which will allow users to receive messages from bot in real time. To make SUSI slack bot you have to follow following steps:


  1. First of all you have to create a team on slack in where your bot will be running. To create a team go to and create a new team.
  2. After creating sign in to your team and got to apps and integration option by clicking on left corner.
  3. Click manage on top right corner and go to custom integrations to add configuration to Bots.
  4. After adding configuration data,bot username and copying API Token now we have to write code for setting bot in slack. To set up code see below steps: 
  5. Install Node.js from the link below on your computer if you haven’t installed it already.
  6. Create a folder with any name and open shell and change your current directory to the new folder you created.
  7. Type npm init in command line and enter details like name, version and entry point.
  8. 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.
  9. Type following commands in command line  npm install –save @slack/client. After slack/client is installed type npm install –save express after express is installed type npm install –save request and then npm install –save http when all the modules are installed check your package.json modules will be included within dependencies portion.
  10. Your package.json file should look like this.
    "name": "slack-bot",
    "version": "1.0.0",
    "description": "SUSI Slack Bot",
    "main": "index.js",
    "dependencies": {
           "express": "^4.15.3",
           "http": "0.0.0",
           "request": "^2.81.0"
    "scripts": {
           "test": "echo \"Error: no test specified\" && exit 1",
           "start": "node index.js"
  11. Copy following code into file you created i.e index.js.
    var Slack = require('@slack/client');
    var request = require('request');
    var express = require('express');
    var http = require('http');
    var app = express();
    var RtmClient = Slack.RtmClient; 
    var RTM_EVENTS = Slack.RTM_EVENTS;
    var token = process.env.APIToken;
    var rtm = new RtmClient(token, { logLevel: 'info' }); 
    //to ping heorku app after 20 minutes to keep it active
    setInterval(function() {
        }, 1200000);
    rtm.on(RTM_EVENTS.MESSAGE, function(message) { 
    var channel =;
    var options = {
           method: 'GET',
           url: '',
           qs: {
               timezoneOffset: '-330',
               q: message.text
    //sending request to SUSI API for response
       request(options, function(error, response, body) {
           if (error) throw new Error(error);
           var ans = (JSON.parse(body)).answers[0].actions[0].expression;
           rtm.sendMessage(ans, channel);
    const port = process.env.PORT || 3000;
    app.listen(port, () => {
       console.log(`listening on ${port}`);

  12. Now we have to deploy this code to heroku.
  13. 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.

  14. To deploy your bot to heroku you need an account on Heroku and after making an account make an app.
  15. Deploy app using github deployment method.
  16. Select Automatic deployment method.
  17. Add APIToken and HerokuUrl variable to heroku app in settings options.
  18. Your SUSI Slack bot is ready enjoy chatting with it.If you want to learn more about slack API refer to

Test SUSI Web App with Facebook Jest

Jest is used by Facebook to test all Javascript codes specially React code snippets. If you need to setup jest on your react application you can follow up these simple steps. But if your React application is made with “create-react-app”, you do not need to setup jest manually. Because it comes with Jest. You can run test using “react-scripts” node module.

Since SUSI chat is made with “create-react-app” we do not need to install and run Jest directly. We executed our test cases using “npm test” it executes “react-scripts test” command. It executes all “.js” files under “__tests__” folders. And all other files with “.spec.js” and “.test.js” suffixes.

React apps that are made from “create-react-app” come with sample test case (smoke test) and that checks whether whole application is built correctly or not. If it passes the smoke test then it starts to run further test cases.

import React from 'react';
import ReactDOM from 'react-dom';
import ChatApp from '../../components/ChatApp.react';
it('renders without crashing', () => {
 const div = document.createElement('div');
 ReactDOM.render( < ChatApp / > , div);

This checks all components which are inside of the “<ChatApp />” component and it check whether all these components integrate correctly or not.

If we need to check only one component in isolated environment. We can use shallow rendering API. we have used shallow rendering API to check each and every component in isolated environment.

We have to install enzyme and test renderer before use it.

npm install --save-dev enzyme react-test-renderer

import React from 'react';
import MessageSection from '../../components/MessageSection.react';
import { shallow } from 'enzyme';
it('render MessageListItem without crashing',()=>{
  shallow(<MessageSection />);

This test case tests only the “MessageListItem”, not its child components.

After executing “npm test” you will get the passed and failed number of test cases.

If you need to see the coverage you can see it without installing additional dependencies.

You just need to run this.

npm test -- --coverage

It will show the output like this.

This view shows how many lines, functions, statements, branches your program has and this shows how much of those covered from the test cases you have.

If we are going to write new test cases for susi chat, we have to make separate file in “__tests__” folder and name it with corresponding file name that we are going to test.

it('your test case description',()=>{
 //test what you need 

Normally test cases looks like test cases you can use “test” instead of “it” .after test case description, there is a fat arrow function. In side this fat arrow function you can add what you need to test

In below example I have compared returned value of the function with static value.

function funcName(){
 return 1;

it('your test case description',()=>{

You have to add your function/variable that need to be tested into “expect()” and value you expect from that function or variable into “toBe()”.  Instead of “toBe()” you can use different functions according to your need.

If you have a long list of test cases you can group them ( using describe()).

describe('my beverage', () => {
  test('is delicious', () => {

  test('is not sour', () => {

This post covers only few things of testing . You can learn more about jest testing from official documentation here.