Preface
We stand on the shoulders of giants. This has been true since the time of Newton (and even before) and it is certainly true now. Much of what we know and learn of programming, we learnt from the pioneering programmers before us and what we leave behind to future generations of programmers is our hard-earned experience and precious knowledge. This book is all about being the scaffolding upon which the next generation of programmers stands when they build the next Sistine Chapel of software.
There are many ways that we can build this scaffolding but one of the best ways is simply to copy from what works. Many programming books attempt to teach with code samples that the readers can reproduce and try it out themselves. This book goes beyond code samples. The reader doesn’t only copy snippets of code or build simple applications but have a chance to take a peek at how a few of the most popular Internet applications today can possibly be built. We explore how these applications are coded and also the rationale behind the way they are designed. The aim is to guide the programmer through the steps of building clones of the various popular Internet applications.
What this book covers
Chapter 1, Cloning Internet Applications gives a brief description of the purpose of the book, the target readers of the book, and a list of the four popular Internet applications we will be cloning in the subsequent chapters. The bulk of this chapter gives a brief run-down on the various technologies we will be using to build those clones.
Chapter 2, URL Shorteners – Cloning TinyURL explains about the first popular Internet application that we investigate and clone in the book, which is TinyURL. This chapter describes how to create a TinyURL clone, its basic principles, and algorithms used.
Chapter 3, Microblogs – Cloning Twitter. The clone in this chapter emulates one of the hottest and most popular Internet web applications now—Twitter. It describes the basic principles of a microblogging application and explains how to recreate a feature-complete Twitter clone.
Chapter 4, Photo -sharing – Cloning Flickr. Flickr is one of the most popular and enduring photo-sharing applications on the Internet. This chapter describes how the reader can re-create a feature complete photo-sharing application the simplest way possible, following the interface and style in Flickr.
Chapter 5, Social Networking Services – Cloning Facebook 1. The final two chapters describe the various aspects of Internet social networking services, focusing on one of the most popular out there now—Facebook. These two chapters also describe the minimal features of a social networking service and show the reader how to implement these features in a complete step-by-step guide. The first part is described in this chapter, which sets the groundwork for the clone and proceeds to describe the data model used in the clone.
Chapter 6, Social Networking Services – Cloning Facebook 2. The final chapter is part two in describing how to create a Facebook clone. This chapter follows on the previous chapter and describes the application flow of the Facebook clone we started earlier.
What you need for this book
Basic Ruby programming skills and basic level operational knowledge of Sinatra, DataMapper, Haml, Blueprint CSS, and MySQL.
Who this book is for
This book is written for web application programmers with an intermediate knowledge of Ruby. The reader should also know how web applications work and have used at least some of the cloned Internet services before.
A typical reader would be a programmer looking to write their own customized TinyURL, Twitter, Flickr, or Facebook. Programmers who want to include features of these Internet services into their own web applications will also find this book interesting.
Conventions
In this book, you will find a number of styles of text that distinguish between different kinds of information. Here are some examples of these styles, and an explanation of their meaning.
Code words in text are shown as follows: “The many-to-many association can be defined with the has n and belongs_to methods.”
A block of code is set as follows:
after :create, :create_wall def create_wall self.wall = Wall.create self.save end
Any command-line input or output is written as follows:
$ sudo gem install Haml
New terms and important words are shown in bold. Words that you see on the screen, in menus or dialog boxes for example, appear in the text like this: “The one big difference is of course, the list of statuses belongs to only that user, and there is a big follow button for the viewing user to follow him.”
Note
Warnings or important notes appear in a box like this.
Tip
Tips and tricks appear like this.
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