firebase-introduction.txt

firebase documentation
- https://firebase.google.com/docs/web/setup

firebase link
- https://firebase.google.com

Create New Project
- give a name to Project

-After Creating project you will get home page panel
-After reaching that particular project select scripting where you want to implememt the project.

-Change in Rule
  auth == null;

-Add firebase in out script
like :-
    <!--Firebase js file -->
    <script src="https://www.gstatic.com/firebasejs/3.6.7/firebase.js"></script>
    <script>
      // Initialize Firebase
      var config = {
        apiKey: "AIzaSyB-efHBg6Abr5q_PC3PR_Ow4s6UzpBPbW0",
        authDomain: "snappy-7328a.firebaseapp.com",
        databaseURL: "https://snappy-7328a.firebaseio.com",
        storageBucket: "snappy-7328a.appspot.com",
        messagingSenderId: "133956073878"
      };
      firebase.initializeApp(config);
    </script>

-Create a database in Firebase

step 1 :- Create database on firebase

step 2 :- Make url in the app.js

    var database = firebase.dataBase();

step 3 :- Make Database Reference
    -it will create an object of the key which specify.

    var databaseRef = firebase.ref("users");

step 4 :- Take snapshot

    databaseRef.on('value',function(snapshot){
        console.log(snapshot);
    });

/* for access value of snapshot */
    databaseRef.on('value',function(snapshot){
        console.log(snapshot.val());
    });

/* Data which you are getting in console is your real time data */

step 5 :- write data with set property with databaseRef

    databaseRef.set({
      "email":"dhiralkaniya3146@gmail.com"
    });

step 6 :- Create userRef is the branch as root with the child so we can add multple record from our website.
//create userRef
    var userRef = database.ref("users");

//Create its branch

    userRef.child("1st-child").set({
      "Name":"Dhiral Kaniya"
    })
    userRef.child("2nd-child").set({
      "Name":"Harmeet Singh",
      "Email":"harmeet@gmail.com"
    });

-sing in with Google

step 1 :- Go to Authentication

step 2 :- Enable Email/password which is specify google password

step 3 :- Add your local Domain to use of Add Domain

step 4 :- go to authentication documentation
      - Google Sign-in authenticaiton

step 5 :- Take Provider from the documentation

step 6 :- Create provider object in the function where we want to authenticate

step 7 :- Take firebase authentication from the documentation

      firebase.auth().signInWithPopup(provider).then(function(result) {
        // This gives you a Google Access Token. You can use it to access the Google API.
        var token = result.credential.accessToken;
        // The signed-in user info.
        var user = result.user;
        // ...
        createUser(user.uid,user.displayName,user.email);
      }).catch(function(error) {
        // Handle Errors here.
        var errorCode = error.code;
        var errorMessage = error.message;
        // The email of the user's account used.
        var email = error.email;
        // The firebase.auth.AuthCredential type that was used.
        var credential = error.credential;
        // ...
      });

//By using above step you can easily embedded google+ in your application with the use of firebase

step 8 :- if the user is successfull create user with the

    function createUser(uid,name,email){
      // Get a reference to the database service
      /*
        This function is call when user is click on sign-in-with google button and its authorised used.
      */
      var database = firebase.database();
      var userRef = database.ref("users");

      var user = {
        id : uid,
        name : name,
        email : email
      }
      userRef.child(uid).set(user).then(function(){
        redirect("chat.html");
      });
    }

step 9 :- Change the database authentication rule with auth != null
-got to the Manage user
-user get the currently signed-in user method
-create ifUserisLoggedIn function
-go through that function
-take that code in to our function
-call that method from the app.js