Automated Data Collection with R: A Practical Guide to Web Scraping and Text Mining by Simon Munzert

A hands on guide to web scraping and text mining for both beginners and experienced users of R
Introduces fundamental concepts of the main architecture of the web and databases and covers HTTP, HTML, XML, JSON, SQL.
Provides basic techniques to query web documents and data sets (XPath and regular expressions).
An extensive set of exercises are presented to guide the reader through each technique.
Explores both supervised and unsupervised techniques as well as advanced techniques such as data scraping and text management.
Case studies are featured throughout along with examples for each technique presented.
R code and solutions to exercises featured in the book are provided on a supporting website.