Book Image

Python Web Scraping - Second Edition

By : Katharine Jarmul
Book Image

Python Web Scraping - Second Edition

By: Katharine Jarmul

Overview of this book

The Internet contains the most useful set of data ever assembled, most of which is publicly accessible for free. However, this data is not easily usable. It is embedded within the structure and style of websites and needs to be carefully extracted. Web scraping is becoming increasingly useful as a means to gather and make sense of the wealth of information available online. This book is the ultimate guide to using the latest features of Python 3.x to scrape data from websites. In the early chapters, you'll see how to extract data from static web pages. You'll learn to use caching with databases and files to save time and manage the load on servers. After covering the basics, you'll get hands-on practice building a more sophisticated crawler using browsers, crawlers, and concurrent scrapers. You'll determine when and how to scrape data from a JavaScript-dependent website using PyQt and Selenium. You'll get a better understanding of how to submit forms on complex websites protected by CAPTCHA. You'll find out how to automate these actions with Python packages such as mechanize. You'll also learn how to create class-based scrapers with Scrapy libraries and implement your learning on real websites. By the end of the book, you will have explored testing websites with scrapers, remote scraping, best practices, working with images, and many other relevant topics.
Table of Contents (10 chapters)

Google search engine

To investigate using our knowledge of CSS selectors, we will scrape Google search results. According to the Alexa data used in Chapter 4, Concurrent Downloading, google.com is the world's most popular website, and conveniently, its structure is simple and straightforward to scrape.


International Google may redirect to a country-specific version, depending on your location. In these examples, Google is set to the Romanian version, so your results may look slightly different.

Here is the Google search homepage loaded with browser tools to inspect the form:

We can see here that the search query is stored in an input with name q, and then the form is submitted to the path /search set by the action attribute. We can test this by doing a test search to submit the form, which would then be redirected to a URL, such as https://www.google.ro/?gws_rd=cr,ssl&ei=TuXYWJXqBsGsswHO8YiQAQ#q=test...