Instant Nokogiri

Hunter Powers

• Publisher: Packt Publishing
• Year: 2013
• ISBN:
  9781783289974
• Edition: 1
• Topic: Informatica
• Subtopic: Programmazione in HTML

In Detail

A wealth of information sits waiting on the Internet. Instant Nokogiri helps you access this information today with Nokogiri, a slick and fast HTML and XML parsing engine. Bundled in an easy-to-use Ruby gem, Nokogiri empowers you to combine disparate data sources and gain an unprecedented insight into your Ruby applications.

"Instant Nokogiri" is a hands-on guide to extracting information from the sources available on the Internet, sources that are not traditionally accessible to developers. You will learn the secrets of identifying content, extracting just the right parts, and incorporating the new data in your Ruby applications.

"Instant Nokogiri" provides step-by-step instructions on how to incorporate the power of the Nokogiri gem and data parsing into your Ruby projects. You will learn all the basics of designing a project around data parsing, exploring disparate data sources, and refining strategies and theories. You will also combine your thoughts in a real-world, real-data sample application. This book will examine common Nokogiri and Ruby methods useful in scraping and parsing complete with practical code samples. You will also learn the secrets behind effective caching, rate limiting, and masking your identity. Instant Nokogiri will teach you how to get targeted data out of HTML and into Ruby, as well as tons of tips, tricks, code snippets, and expert advice.

Approach

Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. A concise, illustrated guide to extracting information available on the Internet using Nokogiri.

Who this book is for

"Instant Nokogiri" is the perfect choice for the aspiring Ruby developer looking to incorporate screen scraping and parsing technology in their applications. Beginner level Ruby, basic HTML, and CSS experience is suggested.

Instant Nokogiri

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Instant Nokogiri

Copyright © 2013 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: August 2013

Production Reference: 1240813

Published by Packt Publishing Ltd.

Livery Place

35 Livery Street

Birmingham B3 2PB, UK.

ISBN 978-1-78328-997-4

www.packtpub.com

Credits

Author

Hunter Powers

Reviewer

Eduardo Figarola Mota

Acquisition Editor

Kunal Parikh

Commissioning Editor

Govindan K.

Technical Editor

Sonali S. Vernekar

Project Coordinator

Sherin Padayatty

Proofreader

Kelly Hutchinson

Production Coordinator

Kyle Albuquerque

Cover Work

Kyle Albuquerque

Cover Image

Abhinash Sahu

About the Author

Hunter Powers, a Full Stack web developer, began programming at the age of 6 and has been gathering steam ever since. From childhood awards (including "Most Outstanding Presentation in the Field of Engineering" from NC State University and "Superior Achievement in Computer Science" from the North Carolina Student Academy of Science) to more recent achievements at TechCrunch Disrupt 2012, he has never lost his passion for the science, languages, and dynamics of computers. His early accomplishments in the field led him to open WireThePlanet.com, his first business, at the age of 13. The company has prospered through the years, developing local and national websites, producing national television advertisements, and directing the art and design for an international card and print company. With a range of products such as websites, book covers, advertising, logos, and national festivals, his customer base includes e-commerce companies, charities and clubs, renowned foodies, and even the weatherman.

In 2011, Powers joined a big data streaming company. His work there has been represented by projects for AOL's TechCrunch, Engadget, The Washington Post, The New York Times, Fox's X-Factor, Fox Sports Australia, New York Presbyterian Hospital, and The NFL, to name a few.

A graduate of The University of Virginia, Powers interests extend beyond technology into filmmaking, photography, and writing. He was first published while in high school in 4 Guys from Rolla and has written many short, as well as a feature length, science fiction and screenplays. Powers also directs with credits for multiple commercial, web videos, and short films.

Currently residing in the Logan Circle arts district in Washington, DC, Powers is working on his next book. You can find his blog at http://www.HunterPowers.com.

About the Reviewer

Eduardo Figarola Mota graduated from the Universidad de Colima with a degree in software engineering. Deeply entrenched in web technologies, he loves programming, and Ruby has become his favorite language.

Currently working for Crowd Interactive, a leading Ruby on Rails consultancy in Mexico, Eduardo finds himself surrounded with cutting-edge technology and Mexico's greatest programming talent.

This is Eduardo's first book serving as Reviewer.

I'd like to thank my friends, family, and girlfriend for the continuous support.

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Chapter 1. Instant Nokogiri

Welcome to Instant Nokogiri. This book has been especially created to provide you with all the information that you need to get set up with Nokogiri. You will learn the basics of Nokogiri, get started with building your first app, and discover some tips and tricks for using Nokogiri.

This book contains the following sections:

So, what is Nokogiri? helps you find out what Nokogiri actually is, what you can do with it, and why it's so great.

Installation explains how to download and install Nokogiri with minimum fuss and then set it up so that you can use it as soon as possible.

Quick start – creating...