Book Image

Go Web Scraping Quick Start Guide

By : Vincent Smith
Book Image

Go Web Scraping Quick Start Guide

By: Vincent Smith

Overview of this book

Web scraping is the process of extracting information from the web using various tools that perform scraping and crawling. Go is emerging as the language of choice for scraping using a variety of libraries. This book will quickly explain to you, how to scrape data data from various websites using Go libraries such as Colly and Goquery. The book starts with an introduction to the use cases of building a web scraper and the main features of the Go programming language, along with setting up a Go environment. It then moves on to HTTP requests and responses and talks about how Go handles them. You will also learn about a number of basic web scraping etiquettes. You will be taught how to navigate through a website, using a breadth-first and then a depth-first search, as well as find and follow links. You will get to know about the ways to track history in order to avoid loops and to protect your web scraper using proxies. Finally the book will cover the Go concurrency model, and how to run scrapers in parallel, along with large-scale distributed web scraping.
Table of Contents (10 chapters)

Searching using the strings package

The most basic way to search for content is to use the strings package from the Go standard library. The strings package allows you to perform various operations on String objects, including searching for matches, counting occurrences, and splitting strings into arrays. The utility of this package can cover some use cases that you may run into.

Example – Counting links

One quick and easy piece of information that we could extract using the strings package is to count the number of links that are contained in a web page. The strings package has a function called Count(), which returns the number of times a substring occurs in a string. As we have seen before, links are contained in...