Highlights: Firebase, Parse & Azure Mobile Services

Cloud back-end services are revolutionary in quick application development. It takes care of routine code. Many times we write services that act as pass through between UI and data store. Consider two tier architecture with cloud back-end services; Your HTML page or mobile app is directly interacting with cloud back-end. More often than not you don't need to develop middle tier. The back end service acts as one.

In this blog I'm attempting write about Firebase, Parse and Azure Mobile Services.

• It's quite easy to integrate C.R.U.D operations in your application using any of these services. 
• They are "cloud" based, so **no** data center or server setup required. They are all ready to hit the ground running.
• This approach is quite useful for mobile app developers who don't have to setup servers around the world to support their user base. Lot of logic can be written client side and these services provide effective data store and related services.
• All of them have user services and authentication related features.

Which additional features each of these back-end services provide? Let's find out.

Firebase Highlights

• Late last year (2014) Google acquired Firebase, a promising back-end service. 
• Firebase data has no schema. Data is represented as JSON objects. Each node or element in the JSON object has it's own URL. So if you need to reference a child node in your code, can do so by directly referencing it's URL.
• Firebase has API for Android, iOS, Web (JavaScript) and REST API. These are many ways in which your code can interact with Firebase.
• Firebase clients are always synchronized. It's a huge. You don't have to write code push message or data changes to the client (or poll from the client). As and when data is modified in the back-end, changes are pushed to all of it's clients.
• It fits naturally with AngularJS. If you are an ng developer you are in luck :)

Here is one of my earlier blogs on Firebase

Firebase

Parse Highlights

• Parse was acquired by Facebook in 2013. They provide back-end services for mobile and web applications.
• Cloud core provides data storage. It too is schema less. But Parse makes it explicit on how to deal with relational data. Refer to this link.
• Parse Cloud Functions allow adding additional logic on Parse server side. You could add additional validations, send push notifications etc (on server side).
• Parse push is a very useful feature. It allows sending push notifications to multiple mobile platforms Android and iOS. You can preview notification, schedule it personalized for the user. For example a notification scheduled for 11 AM in the morning in U.S. wouldn't wake up customer in India middle of the night. Rather personalizes to send it at 11 AM India time.
• JavaScript perspective Parse fits naturally with backbone style of coding. It supports huge list of technologies and platforms. Refer to the image for list.
• Finally Parse features Core and Push could be used independently. You don't need to be using Core to use Push and vice versa.

A link to my earlier blog on Parse

Azure Mobile Services Highlights

It's little tricky to include Azure Mobile Services in this list. It's one of many features and services Microsoft Azure provides. I believe it fits in the category of Parse and Firebase as it provides lot of out of box features for faster development and integration of back-end services.

• Schema: Azure Mobile Services by default uses MS SQL Server for data storage. As it's possibly using code first, you don't have to define columns (schema). They are effectively created on the fly. 
• Unlike other back-end services, with Azure Mobile Services you can chose data storage from SQL Server, Mongo DB and Azure Storage
• You have a choice for backend technology as well between .net and JavaScript (NodeJS)
• Similar to Parse Cloud Functions Azure Mobile Services allow adding additional code on server side. In Azure Management Portal, select your Azure Mobile Services, go to data tab, select the table and select Script tab. Use drop down to modify script for add or update or retrieve or delete operations.
• Azure Mobile Services provide Push Notifications across mobile platforms Windows, Android and iOS. It integrates with MPNS (Windows),  APN (iOS) and GCM (Android) services for push notifications.
• Azure Mobile Services have APIs for following platforms,

Here are my earlier blogs on Azure Mobile Services, Mongo DB with Azure Mobile Service, Push Notifications for Phone App using Azure Mobile Services and Windows Azure Mobile Services for Connected Apps

In conclusion one of the biggest advantages of cloud back-end services is time to develop. They reduce lot of routine code and provides features out of box. 

Parse as your app's backend

Parse is a cloud based backend service. For an application either a mobile app or a web app, Parse provides storage, SDK for easy integration and cloud services for additional processing including push notification support, analytics etc.

Parse provides APIs for variety of technologies. This blog is focusing on JavaScript. The framework is inspired by backbone and it's style of coding in JavaScript. Lot of articles use Handlebars and other templates in their examples. For simplicity, I'm using JQuery in this blog.

Get Started

1. Once you register and login at Parse.com, create an app and launch quick start guide for it.
2. Choose Data - Web - and New Project
3. Here you can chose to download a blank HTML/JavaScript project or explore APIs to be added in an existing project.

Core

Parse Core provides data storage, retrieval and Data Browser. The Data Browser allows you to create one or more classes (which can be visualized as a table - refer to the screenshot). Here you can add/delete and modify data. It's the same data your app is integrating with, so changes are reflected in your app automatically (as you refresh screens).

Click on Add Class - provide name. It creates a table with default columns like objectId, CreatedAt, updatedAt etc. Click +cols to start adding custom columns.

Now, get started with code-

// Get started with initialize function

Parse.initialize("[application_id]", "[JavaScript Key]");



You get these keys as soon as you create the app. You could go to Key's screen to view and copy all available keys. If you chose to download the blank template you may use boilerplate code.

Create an object of class created in Data Browser. I'm referring to a class named book in my example.

var Book = Parse.Object.extend("book");

// Now create an object of book.
var book = new Book();

C.R.U.D

Following code demonstrates Create, Retrieval, Update and Delete of books data
// Create new records
// use set
book.set("aKey", "aValue");


Key here is same as column name in Data Browser

// Or set all column values at one-go.
book.set({aKey: 'aValue', secondKey: 'secondValue'});

//save creates the record for the table/class
// you may pass above object instead of null/first param. Then set is not required
book.save(null, {success: function(response){
   // On successful save response has all saved records.
}, error: function(error){
  // error information if occurred is in error object.
}
});


// ----------------------------------------------------------------- // Retrieval
// To Parse.Query function pass the class 
// Book below is not new'ed. It's returned value of Parse.Object.extend(). Refer to code above.
var query = new Parse.Query(Book);

// You may filter with queries like below. This looks for key with a value specified
query.equalTo("key", "value");

//or directly calling find() returns all records
query.find({
success: function(results){
for (i in results){
var data = results[i];

    // addBookRow() updates DOM with new row.
addBookRow(data.get("title"),
data.get("author"),
data.get("publisher"));
}
},
error: function(error){
$(".error").hide();
console.error(error);
}

// ----------------------------------------------------------------- // Update by getting an instance of book class for an existing record.
// I used find() for it.
query.find({
   success: function(result){
        // Get first row from results
var row = result[0];

        // update the first "title" column with new value
        row.set("title", "new value");
        row.save(null, { success: function(){}, error: function(){}});

   }
});

// -----------------------------------------------------------------
// Delete by getting an instance of book class for an existing record
// Used query.find to get it
query.find({
   success: function(result){
        // Get first row from results
var row = result[0];

        // Delete with destroy function.
        row.destory({ success: function(){}, error: function(){}});

   }
});

Refer to complete sample here

This is a introductory blog on Parse, planning to followup with concepts of

• More queries and explore more of JavaScript parse library
• Cloud code - additional hooks and validations on cloud. It's server side logic. Used instead of adding complex logic with-in a browser or a mobile app.
• Parse Push - Easy integration of Push for various mobile platforms. Currently it's only for mobile devices.

Have fun Parsing!