Node Authentication using passport.js - Part 2

This is the part two of the passport authentication blog series. if you have missed the part one, please read the Node authentication - part one https://cloudnweb.dev/2019/04/node-authentication-using-passport-js-part-1/

In this article, we will see how to integrate login using passport authentication.

Firstly, add the login template in views folder. create a file login.handlebars in views folder

1{{#if message}}
2        <div class="ui negative message transition hidden">
3            <i class="close icon"></i>
4            <div class="header">
5                {{message}}
6            </div>
7        </div>
8    {{/if}}
9    <div class="ui middle aligned center aligned grid container">
10        <div class="column">
11            <h2 class="ui teal image header">
12                <img src="/images/favicon.png" class="image"/>
13                <div class="content">
14                    Cloudnweb.dev
15                </div>
16            </h2>
17            <form action="/login" method="POST" class="ui large form">
18                <div class="ui stacked segment">
19                    <div class="field">
20                        <div class="ui left icon input">
21                            <i class="user icon"></i>
22                            <input type="text" name="email" placeholder="Enter Email Address"/>
23                        </div>
24                    </div>
25                    <div class="field">
26                        <div class="ui left icon input">
27                            <i class="lock icon"></i>
28                            <input type="password" name="password" placeholder="Enter Password"/>
29                        </div>
30                    </div>
31                    <input type="submit" class="ui fluid large teal submit button" value="Login">                </div>
32            </form>
33            <div class="ui message">
34                New Here?
35                <a href="/signup">Sign Up</a>
36            </div>
37        </div>
38    </div>

After that, we add the login routes in the routes folder. So, add the following code in routes/index.js

1app.get("/login", (req, res) => {
2  res.render("login")
3})
4
5app.post(
6  "/login",
7  passport.authenticate("local-login", {
8    successRedirect: "/",
9    failureRedirect: "/login",
10    failureFlash: true,
11  })
12)

In the above code, passport is a middleware that uses the strategy called local-login in the config/passport.js

Therefore, add the following code in config/passport.js

1passport.use(
2  "local-login",
3  new LocalStrategy(
4    {
5      // by default, local strategy uses username and password, we will override with email
6      usernameField: "email",
7      passwordField: "password",
8      passReqToCallback: true, // allows us to pass back the entire request to the callback
9    },
10    function(req, email, password, done) {
11      // callback with email and password from our form
12
13      // find a user whose email is the same as the forms email
14      // we are checking to see if the user trying to login already exists
15      User.findOne({ email: email }, function(err, user) {
16        // if there are any errors, return the error before anything else
17        if (err) return done(err)
18        console.log("user", user)
19        console.log("password", password)
20        // if no user is found, return the message
21        if (!user)
22          return done(null, false, req.flash("loginMessage", "No user found.")) // req.flash is the way to set flashdata using connect-flash
23
24        // if the user is found but the password is wrong
25        if (!user.validPassword(password))
26          return done(
27            null,
28            false,
29            req.flash("loginMessage", "Oops! Wrong password.")
30          ) // create the loginMessage and save it to session as flashdata
31
32        // all is well, return successful user
33        return done(null, user)
34      })
35    }
36  )
37)

Mainly, it checks whether the email is exists in the database and check the passport. as a result, it will return the success of the login to the route.

In conclusion, we can run the application using node app.js

complete source code can be found here: https://github.com/ganeshmani/node-travis

To read more about passport : http://www.passportjs.org/docs/