Implementing Sign in with Twitter for Node.js

Implementing Sign in with Twitter for Node.js

In Node.js, it is very easy to add Twitter sign in to an Express web app.Twitter uses the standard OAuth for authentication, which means you incorporate a standardized way of logging in if you use Twitter sign in.

Twitter uses the standard OAuth for authentication, which means you incorporate a standardized way of logging in if you use Twitter sign in.

In Node.js, it is very easy to add Twitter sign in to an Express web app.

Getting Started

First, you have to make an Express app. Express is a routing library with a lot of add-ons built for easy web development.

There are many Express app boilerplates available on the web. There is also an Express code generator from the makers of the Express framework.

Using the latest Node.js versions, you can run npx express-generator.

If npx is not available, you can install express-generator globally and run that:

$ npm install -g express-generator
$ express

Make a folder for your project and follow the instructions.

To make the example simple, this app will provide the redirect URL that you get after providing the consumer key and request token for the Angular app.

Then, after the user goes through the Twitter sign in, it will redirect back to the Angular app, which will then call the Express API to save the OAuth access token and the OAuth access token secret to a database.

We need to make an entry point file for Express.

We need to install express-session, express-logger, cookie-parser, and cors for saving sessions, logging, parsing cookies, and allowing external requests for our Angular app, respectively.

babel-register and bale-polyfill are required to use the latest JavaScript features in our Node.js web app.

To save the secrets, use the [dotenv](https://www.npmjs.com/package/dotenv) library. With this, the secrets will be read from the .env file, rather than hard coding them into the code, which is very bad secret practice.

To get the Twitter keys, you have to apply for a developer account at https://developer.twitter.com/. You will then get the keys and secrets required, which you will put into the .env file.

The .env file should be a key-value list, like this:

TWITTER_CONSUMER_KEY=''
TWITTER_CONSUMER_SECRET=''
TWITTER_CALLBACK_URL='[http://localhost:4200](http://localhost:4200/settings' "http://localhost:4200")'
SESSION_SECRET=''

I will call the entry point file app.js .

To run this, go to your project folder and run node app.js:

require("@babel/register");
require("babel-polyfill");
require('dotenv').config();
const express = require('express');
const bodyParser = require('body-parser');
const logger = require('express-logger');
const cookieParser = require('cookie-parser');
const session = require('express-session');
const cors = require('cors');
const sessions = require('./controllers/sessionsController');
const app = express();
app.use(cors())
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
app.use(logger({ path: "log/express.log" }));
app.use(cookieParser());
app.use(session({ secret: process.env.SESSION_SECRET, resave: false, saveUninitialized: true }));
app.use((req, res, next) => {
  res.locals.session = req.session;
  next();
});
app.use('/sessions', sessions);
app.listen(8080, () => {
  console.log('App running on port 8080!');
});

app.js

Then, we need the oauth library to make an oauth.OAuth object which will allow the Express app to get the request token and request token secret.

Add a controllers folder in the same level as app.js.

Then, add sessionsController.js into the controllers folder.

Add the following to sessionsController.js:

const express = require('express');
const router = express.Router();
const CryptoJS = require("crypto-js");
const oauth = require('oauth');
const _twitterConsumerKey = process.env.TWITTER_CONSUMER_KEY;
const _twitterConsumerSecret = process.env.TWITTER_CONSUMER_SECRET;
const twitterCallbackUrl = process.env.TWITTER_CALLBACK_URL;
const consumer = new oauth.OAuth("https://twitter.com/oauth/request_token", "https://twitter.com/oauth/access_token",_twitterConsumerKey, _twitterConsumerSecret, "1.0A", twitterCallbackUrl, "HMAC-SHA1");
router.get('/connect', (req, res) => {
  consumer.getOAuthRequestToken(function (error, oauthToken,   oauthTokenSecret, results) {
    if (error) {
      res.send(error, 500);
    } else {
      req.session.oauthRequestToken = oauthToken;
      req.session.oauthRequestTokenSecret = oauthTokenSecret;
      const redirect = { 
redirectUrl: `https://twitter.com/oauth/authorize?  oauth_token=${req.session.oauthRequestToken}`
    }
      res.send(redirect);
    }
  });
});
router.get('/saveAccessTokens', authCheck, (req, res) => {
  consumer.getOAuthAccessToken(
  req.query.oauth_token,
  req.session.oauthRequestTokenSecret,
  req.query.oauth_verifier,
  (error, oauthAccessToken, oauthAccessTokenSecret, results) => {
    if (error) {
      logger.error(error);
      res.send(error, 500);
    }
    else {
      req.session.oauthAccessToken = oauthAccessToken;
      req.session.oauthAccessTokenSecret = oauthAccessTokenSecret
      return res.send({ message: 'token saved' });
    }
  });
});
module.exports = router;

sessionsController.js

The connect route will send the Twitter sign-in URL as the redirect URL.

Then, the Angular app will call the saveAccessTokens route to store the OAuth access token and its secret in the session.

Angular CLI

To build the Angular app, you need the Angular CLI.

To install it, run npm i -g @angular/cli in your Node.js command prompt. Then, run ng new frontend to generate the skeleton code for your front end app.

Also, install @angular/material according to the Angular documentation.

After that, replace the default app.module.ts with the following:

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
import {
  MatButtonModule,
  MatTableModule,
  MAT_DIALOG_DEFAULT_OPTIONS,
} from '@angular/material';
import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { SettingsPageComponent } from './settings-page/settings-page.component';
import { HttpClientModule, HTTP_INTERCEPTORS } from '@angular/common/http';
import { SessionService } from './session.service';
import { HttpReqInterceptor } from './http-req-interceptor';
@NgModule({
  declarations: [
    AppComponent,
    SettingsPageComponent,
  ],
  imports: [
    BrowserModule,
    AppRoutingModule,
    BrowserAnimationsModule,
    MatButtonModule,
    FormsModule,
    HttpClientModule,
  ],
  providers: [
    SessionService,
    {
      provide: HTTP_INTERCEPTORS,
      useClass: HttpReqInterceptor,
      multi: true
    },
    UserService,
    TweetsService,
  ],
  bootstrap: [AppComponent],
})
export class AppModule { }

app.module.ts

We need to use Angular’s HTTP client to connect to our Express routes to get the redirect URL and get the access token from the redirect after logging in with Twitter, then send it back to our route.

To do this, run ng g service session.

This will create session.service.ts:

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { environment } from 'src/environments/environment';
@Injectable({
  providedIn: 'root'
})
export class SessionService {
  constructor(private http: HttpClient) { }
  getRedirectUrl() {
  return this.http.get(`${environment.apiUrl}/sessions/connect`)
}
  saveAccessToken(oauthToken: string, oauthVerifier: string) {
    return this.http.get(`${environment.apiUrl}/sessions/saveAccessTokens?oauth_token=${oauthToken}&oauth_verifier=${oauthVerifier}`)
  }
}

session.service.ts

In here, environment.apiUrl is the URL to our API, which is specified in environment.ts.

Now, we need a page with a button that calls our Express route to get the redirect URL.

Run ng g component settingsPage to create settings-page.component.ts and settings-page.component.html, which is where the button will be placed.

Add the following to settings-page.component.html:

<div>
  <button mat-raised-button (click)='redirectToTwitter()'>Connect to Twitter Account</button>
</div>

Then, add the following settings-page.component.ts:

import { Component, OnInit } from '@angular/core';
import { ActivatedRoute } from '@angular/router';
import { SessionService } from '../session.service';
@Component({
  selector: 'app-settings-page',
  templateUrl: './settings-page.component.html',
  styleUrls: ['./settings-page.component.scss']
})
export class SettingsPageComponent implements OnInit {
  constructor(
    private activatedRoute: ActivatedRoute,
    private sessionService: SessionService,
  ) {
    this.activatedRoute.queryParams.subscribe(params => {
      const oauthVerifier = params['oauth_verifier'];
      const oauthToken = params['oauth_token'];
      if (oauthToken && oauthVerifier) {
        this.saveAccessToken(oauthToken, oauthVerifier);
      }
    });
  }
  ngOnInit() {}
  saveAccessToken(oauthToken: string, oauthVerifier: string) {
    this.sessionService.saveAccessToken(oauthToken, oauthVerifier).subscribe(res => {
    alert('Token saved');
    })
  }
  redirectToTwitter() {
    this.sessionService.getRedirectUrl().subscribe((res: any) => {
      location.href = res.redirectUrl;
    })
  }
}

settings-page.component.ts

After adding the code above, you get a button that, after you click it, will go to the Twitter sign in page.

Then, once Twitter sign in succeeds, you will be redirected to the same page with the OAuth access token and verifier, which will be sent to our Express API and stored in the session.

Token Saved

You will get Token saved message once it succeeds.

In the end, this is the workflow you should get:

  1. First, you get the connect button:

  1. Then, you are redirected to the Twitter login:

  1. Finally, you are redirected back with the OAuth access token and verifier, and with those, you get the access token and secret which will be stored to the session.

If that succeeds, the saveAccessTokens route will return a successful response, which will then trigger the Angular app to alert Token saved.

How to get started Internationalization in JavaScript with NodeJS

How to get started Internationalization in JavaScript with NodeJS

Tutorial showing how to use the Intl JS API in NodeJS (i18n). We'll install a module to unlock the Intl API languages for Node and test out RelativeTimeFormat to translate and localise relative times in JavaScript.

Tutorial showing how to use the Intl JS API in NodeJS (i18n). We'll install a module to unlock the Intl API languages for Node and test out RelativeTimeFormat to translate and localise relative times in JavaScript. I'll tell you how to get started with the built-in internationalization library in JS for Node 12 and higher. We'll change the locale to see how the translation works and test different BCP 47 language tags.

Internationalization is a difficult undertaking but using the Intl API is an easy way to get started, it's great to see this new API in the JS language and available for use. Soon, you'll be able to have confidence using it in the browser as modern browsers support the major Intl features. Have a look at the browser compatibility charts to see which browsers and versions of node are supported.

Use Intl.RelativeTimeFormat for language-sensitive relative time formatting.
#javascript #nodejs #webdevelopment

MDN Documentation:

https://developer.mozilla.org/en-US/d...

Full ICU NPM package:

https://www.npmjs.com/package/full-icu

JavaScript Tutorial: if-else Statement in JavaScript

JavaScript Tutorial: if-else Statement in JavaScript

This JavaScript tutorial is a step by step guide on JavaScript If Else Statements. Learn how to use If Else in javascript and also JavaScript If Else Statements. if-else Statement in JavaScript. JavaScript's conditional statements: if; if-else; nested-if; if-else-if. These statements allow you to control the flow of your program's execution based upon conditions known only during run time.

Decision Making in programming is similar to decision making in real life. In programming also we face some situations where we want a certain block of code to be executed when some condition is fulfilled.
A programming language uses control statements to control the flow of execution of the program based on certain conditions. These are used to cause the flow of execution to advance and branch based on changes to the state of a program.

JavaScript’s conditional statements:

  • if
  • if-else
  • nested-if
  • if-else-if

These statements allow you to control the flow of your program’s execution based upon conditions known only during run time.

  • if: if statement is the most simple decision making statement. It is used to decide whether a certain statement or block of statements will be executed or not i.e if a certain condition is true then a block of statement is executed otherwise not.
    Syntax:
if(condition) 
{
   // Statements to execute if
   // condition is true
}

Here, condition after evaluation will be either true or false. if statement accepts boolean values – if the value is true then it will execute the block of statements under it.
If we do not provide the curly braces ‘{‘ and ‘}’ after if( condition ) then by default if statement will consider the immediate one statement to be inside its block. For example,

if(condition)
   statement1;
   statement2;

// Here if the condition is true, if block 
// will consider only statement1 to be inside 
// its block.

Flow chart:

Example:

<script type = "text/javaScript"> 

// JavaScript program to illustrate If statement 

var i = 10; 

if (i > 15) 
document.write("10 is less than 15"); 

// This statement will be executed 
// as if considers one statement by default 
document.write("I am Not in if"); 

< /script> 

Output:

I am Not in if
  • if-else: The if statement alone tells us that if a condition is true it will execute a block of statements and if the condition is false it won’t. But what if we want to do something else if the condition is false. Here comes the else statement. We can use the else statement with if statement to execute a block of code when the condition is false.
    Syntax:
if (condition)
{
    // Executes this block if
    // condition is true
}
else
{
    // Executes this block if
    // condition is false
}


Example:

<script type = "text/javaScript"> 

// JavaScript program to illustrate If-else statement 

var i = 10; 

if (i < 15) 
document.write("10 is less than 15"); 
else
document.write("I am Not in if"); 

< /script> 

Output:

i is smaller than 15
  • nested-if A nested if is an if statement that is the target of another if or else. Nested if statements means an if statement inside an if statement. Yes, JavaScript allows us to nest if statements within if statements. i.e, we can place an if statement inside another if statement.
    Syntax:
if (condition1) 
{
   // Executes when condition1 is true
   if (condition2) 
   {
      // Executes when condition2 is true
   }
}

Example:

<script type = "text/javaScript"> 

// JavaScript program to illustrate nested-if statement 

var i = 10; 

if (i == 10) { 

// First if statement 
if (i < 15) 
	document.write("i is smaller than 15"); 

// Nested - if statement 
// Will only be executed if statement above 
// it is true 
if (i < 12) 
	document.write("i is smaller than 12 too"); 
else
	document.write("i is greater than 15"); 
} 
< /script> 

Output:

i is smaller than 15
i is smaller than 12 too
  • if-else-if ladder Here, a user can decide among multiple options.The if statements are executed from the top down. As soon as one of the conditions controlling the if is true, the statement associated with that if is executed, and the rest of the ladder is bypassed. If none of the conditions is true, then the final else statement will be executed.
if (condition)
    statement;
else if (condition)
    statement;
.
.
else
    statement;


Example:

<script type = "text/javaScript"> 
// JavaScript program to illustrate nested-if statement 

var i = 20; 

if (i == 10) 
document.wrte("i is 10"); 
else if (i == 15) 
document.wrte("i is 15"); 
else if (i == 20) 
document.wrte("i is 20"); 
else
document.wrte("i is not present"); 
< /script> 

Output:

i is 20

How to Retrieve full Profile of LinkedIn User using Javascript

How to Retrieve full Profile of LinkedIn User using Javascript

I am trying to retrieve the full profile (especially job history and educational qualifications) of a linkedin user via the Javascript (Fetch LinkedIn Data Using JavaScript)

Here we are fetching LinkedIn data like Username, Email and other fields using JavaScript SDK.

Here we have 2 workarounds.

  1. Configuration of linkedIn developer api
  2. Javascript Code to fetch records

Configuration of linkedIn developer api

In order to fetch records, first we need to create developer api in linkedin which will act as token/identity while fetching data from other linkedin accounts.

So to create api, navigate to https://linkedin.com/developer/apps and click on 'Create Application'.

After navigating, fill in details like name, description and other required fields and then submit.

As we submit, it will create Client ID and Client Secret shown below, which we will be using in our code while communicating to fetch records from other LinkedIn account.

Note: We need to provide localhost Url here under Oauth 2.0. I am using my localhost, but you can probably use other production URLs under Oauth 2.0 where your app is configured. It will make your api  consider the Url as trusted which fetching records.

Javascript Code to fetch records

For getting user details like first name, last name,User image can be written as,

<script type="text/javascript" src="https://platform.linkedin.com/in.js">  
    api_key: XXXXXXX //Client ID  
    onLoad: OnLinkedInFrameworkLoad //Method that will be called on page load  
    authorize: true  
</script>  
<script type="text/javascript">  
    function OnLinkedInFrameworkLoad() {  
        IN.Event.on(IN, "auth", OnLinkedInAuth);  
    }  
  
    function OnLinkedInAuth() {  
        IN.API.Profile("me").result(ShowProfileData);  
    }  
  
    function ShowProfileData(profiles) {  
        var member = profiles.values[0];  
        var id = member.id;  
        var firstName = member.firstName;  
        var lastName = member.lastName;  
        var photo = member.pictureUrl;  
        var headline = member.headline;  
        //use information captured above  
        var stringToBind = "<p>First Name: " + firstName + " <p/><p> Last Name: " + lastName + "<p/><p>User ID: " + id + " and Head Line Provided: " + headline + "<p/>"  
        document.getElementById('profiles').innerHTML = stringToBind;  
    }  
</script>    

Kindly note we need to include 'https://platform.linkedin.com/in.js' as src under script type as it will act on this Javascript SDK provided by Linkedin.

In the same way we can also fetch records of any organization with the companyid as keyword.

<head>  
    <script type="text/javascript" src="https://platform.linkedin.com/in.js">  
        api_key: XXXXXXX ////Client ID  
        onLoad: onLinkedInLoad  
        authorize: true  
    </script>  
</head>  
  
<body>  
    <div id="displayUpdates"></div>  
    <script type="text/javascript">  
        function onLinkedInLoad() {  
            IN.Event.on(IN, "auth", onLinkedInAuth);  
            console.log("On auth");  
        }  
  
        function onLinkedInAuth() {  
            var cpnyID = XXXXX; //the Company ID for which we want updates  
            IN.API.Raw("/companies/" + cpnyID + "/updates?event-type=status-update&start=0&count=10&format=json").result(displayCompanyUpdates);  
            console.log("After auth");  
        }  
  
        function displayCompanyUpdates(result) {  
            var div = document.getElementById("displayUpdates");  
            var el = "<ul>";  
            var resValues = result.values;  
            for (var i in resValues) {  
                var share = resValues[i].updateContent.companyStatusUpdate.share;  
                var isContent = share.content;  
                var isTitled = isContent,  
                    isLinked = isContent,  
                    isDescription = isContent,  
                    isThumbnail = isContent,  
                    isComment = isContent;  
                if (isTitled) {  
                    var title = isContent.title;  
                } else {  
                    var title = "News headline";  
                }  
                var comment = share.comment;  
                if (isLinked) {  
                    var link = isContent.shortenedUrl;  
                } else {  
                    var link = "#";  
                }  
                if (isDescription) {  
                    var description = isContent.description;  
                } else {  
                    var description = "No description";  
                }  
                /* 
                if (isThumbnailz) { 
                var thumbnailUrl = isContent.thumbnailUrl; 
                } else { 
                var thumbnailUrl = "http://placehold.it/60x60"; 
                } 
                */  
                if (share) {  
                    var content = "<a target='_blank' href=" + link + ">" + comment + "</a><br>";  
                    //el += "<li><img src='" + thumbnailUrl + "' alt=''>" + content + "</li>";  
                    el += "<li><div>" + content + "</div></li>";  
                }  
                console.log(share);  
            }  
            el += "</ul>";  
            document.getElementById("displayUpdates").innerHTML = el;  
        }  
    </script>  
</body>  

We can get multiple metadata while fetching records for any any organization. We can get company updates as shown below.

Conclusion

We can also fetch any company specific data like company job updates/post, total likes, comments, and number of views along with a lot of metadata we can fetch which I have shown below.

Thank you for reading !