Book Image

Python Web Scraping Cookbook

By : Michael Heydt
Book Image

Python Web Scraping Cookbook

By: Michael Heydt

Overview of this book

Python Web Scraping Cookbook is a solution-focused book that will teach you techniques to develop high-performance scrapers and deal with crawlers, sitemaps, forms automation, Ajax-based sites, caches, and more. You'll explore a number of real-world scenarios where every part of the development/product life cycle will be fully covered. You will not only develop the skills needed to design and develop reliable performance data flows, but also deploy your codebase to AWS. If you are involved in software engineering, product development, or data mining (or are interested in building data-driven products), you will find this book useful as each recipe has a clear purpose and objective. Right from extracting data from the websites to writing a sophisticated web crawler, the book's independent recipes will be a godsend. This book covers Python libraries, requests, and BeautifulSoup. You will learn about crawling, web spidering, working with Ajax websites, paginated items, and more. You will also learn to tackle problems such as 403 errors, working with proxy, scraping images, and LXML. By the end of this book, you will be able to scrape websites more efficiently and able to deploy and operate your scraper in the cloud.
Table of Contents (13 chapters)

Querying data with XPath and CSS selectors

CSS selectors are patterns used for selecting elements and are often used to define the elements that styles should be applied to. They can also be used with lxml to select nodes in the DOM. CSS selectors are commonly used as they are more compact than XPath and generally can be more reusable in code. Examples of common selectors which may be used are as follows:

What you are looking for Example
All tags *
A specific tag (that is, tr) .planet
A class name (that is, "planet") tr.planet
A tag with an ID "planet3" tr#planet3
A child tr of a table table tr
A descendant tr of a table table tr
A tag with an attribute (that is, tr with id="planet4") a[id=Mars]

Getting ready

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