Firebase

Making App

Go to firebase console and copy pasta the code they give you to setup connection.

Using Database/Firestore

Firestore allows you to live update data on as many devices as you want on the frontend. Add listeners to data.

• For testing go to db setting, rules, and set read and write to true(allowing all users to read and write no auth)

• Then you can add data

• the DbRef gets the key value pair from text and on change changes the val of snap

  var bigOne = document.getElementById('bigOne');
  var dbRef = firebase.database().ref().child('text');
  dbRef.on('value', snap => bigOne.innerText = snap.val());

Firebase Authenication

Allows ease console setup of Facebook auth, twitter, github, etc where all the user objects look the same

const auth = firebase.auth();
auth.signInWithEmailAndPassoword(email, pass);
//return a promise where you can resolve that user
auth.createUserWithEmailAndPassword(email, pass);
 //another promise
auth.onAuthStateChanged(firebaseUser => { });
//fires callback on changes, firebaseUser = null when logout

Using the promise

const promise = auth.signInWithEmailAndPassoword(email, pass);
promise.catch(e => console.log(e, message));

Signup event

function signUp(email, pass)) {
  const promise = auth.createUserWithEmailAndPassword(email, pass);
  promise.catch(e => console.log(e.message));
  //catch errors but dont do anything on state change just make request
  //using promise then would not allow auth changes
}

//SIGNOUT
firebase.auth().signOut();

//handle the auth state changes here
firebase.auth().onAuthStateChanged(firebaseUser => {
  if(firebaseUser) {
    //logged in
  } else {
    //not logged in
  }
})

Ref Objects

In the cloud, event.data.ref

• .child('specificChild')

• .set(value) //returns promise

Delta Snapshot

• .ref //to get about ref

• .changed() //boolean if changed

• .val() //to get the actual value there

Getting val

ref.once('value')
  .then(function(dataSnapshot) {
    // handle read data.
  });

Adding Backend APIS / Cloud Functions

Could do clientside, but like secrets on client?? and write for every platform?? Require the APIS apparently @google-cloud/speech can be require(nodejs right). Then you add listener to upload file and then use api then write to translationed file. So you handle the conversion clientside. Then deploy these

Setup

Need firebase CLI npm install -g firebase-tools firebase login

Start Project firebase init functions firebase deploy

Return the promise from the set method to allow it to wait or null/

Basic Usage

functions.database/firestore.ref('/somepath/1') Can do:

• onWrite(), created, updated, or deleted

• onCreate(), created

• onUpdate(), updated

• onDelete(), deleted

Return a null or a promise to be waited for b4 cleaning up

exports.test = functions.database
.ref('/games/1')
  .onUpdate(event => {
    const game = event.data.val() //game object
    return null
  }

Get specific changes

Use .params.[key] to get the wildcard routes

exports.locationChange = functions.database
  .ref('/games/1/players/{playerId}/location')
  .onUpdate(event => {
    const location = event.data.val();
    console.log("LOC change");
    console.log(location);
    console.log(event.params.playerId)

Promises

Can use the promises as promises with then chains and all and such

const p1Update = event.data.ref.child(pId).child("potentialHacks").set(curPotentialHacks);
const p2Update = event.data.ref.child(changedPId).child("potentialHacks").set(changedPotentialHacks);
return Promise.all([p1Update, p2Update]);

Modularize Files

Nodejs style simply require i.e const location = require('./location.js');