Successfully scrape data from any website with the power of PythonAbout This Book* A hands-on guide to web scraping with real-life problems and solutions* Techniques to download and extract data from complex websites* Create a number of different web scrapers to extract informationWho This Book Is ForThis book is aimed at developers who want to use web scraping for legitimate purposes. Prior programming experience with Python would be useful but not essential. Anyone with general knowledge of programming languages should be able to pick up the book and understand the principals involved.What You Will Learn* Extract data from web pages with simple Python programming* Build a threaded crawler to process web pages in parallel* Follow links to crawl a website* Download cache to reduce bandwidth* Use multiple threads and processes to scrape faster* Learn how to parse JavaScript-dependent websites* Interact with forms and sessions* Solve CAPTCHAs on protected web pages* Discover how to track the state of a crawlIn DetailThe Internet contains the most useful set of data ever assembled, largely publicly accessible for free. However, this data is not easily reusable. It is embedded within the structure and style of websites and needs to be carefully extracted to be useful. Web scraping is becoming increasingly useful as a means to easily gather and make sense of the plethora of information available online. Using a simple language like Python, you can crawl the information out of complex websites using simple programming.This book is the ultimate guide to using Python to scrape data from websites. In the early chapters it covers how to extract data from static web pages and how to use caching to manage the load on servers. After the basics we'll get our hands dirty with building a more sophisticated crawler with threads and more advanced topics. Learn step-by-step how to use Ajax URLs, employ the Firebug extension for monitoring, and indirectly scrape data. Discover more scr