To begin with lets understand what is web scraping exactly, so as the name suggest web scrapping is nothing but gathering data from various sources it is also called as web harvesting or web data scraping. It collects structured web data in an automated way. Some of the main uses of web scraping are money monitoring, news monitoring, market research and many more along the same lines. Web scraping helps when one wants to get data from but doesn’t have API or has API but its use is limited. So in general web scraping is used by businesses that want to make the most out of their knowledge by making using of all the data available to make smarter decisions. Everyone uses web scraping but doesn’t realise it the most basic copy paste mechanism is also a form of web scraping. The only difference being it is at a very microscopic level. Data is an important asset and it is important to know how one can scrap the most out of the available ones. Scraping is very easy and the way of work is in two parts. Part 1 being the web crawler and part 2 being the web scraper. Web crawler is also called as web spider it basically crawls through the web and searches for links and exploring content. Whereas web scraper is a nicely designed tool for scraping all the data that the crawler finds. Web scraper have varied designs depending on the complexity.
In this article we will see few tools that are used to scrap web or for web harvesting,
This is a Python tool used for scraping data from HTML and XML files. The main of this design is screen scraping. This library provides simple idioms and methods for navigating, searching and modifying. It automatically converts incoming data into unicode and outgoing documents to UTF-8.
This is a tool for C libraries. It is considered to be one of the most popular and easy to use tool to scrap data from HTML and XML. The uniqueness of this is that it combines the speed and XML features of these libraries with simplicity of native Python.
This is a tool for automating interaction with websites. The main feature of this tool is that it send and accepts cookies, follows links and submits forms. However this tool was unused for a very long time because it couldn’t support Python 3.
It is a open source and collaborative tool for extracting data that one may need from the website. It is also the fastest high level python framework for crawling and scraping data which was written in Python. It has a wide range of uses from data mining to automation. It is a framework that writes spiders that crawl in the website. It is a application tool. Scrapy uses the spiders to scrape information from website.
Selenium is basically a set of different software tools each of which has a different approach to testing automation selenium Python is an open source web based automation tool that provides simple API. With the help of this a web developer can access all functionalities of selenium web driver in a simple way.
It is a tool used for opening URLs. It collects several modules for working with URL such as request for opening and reading URL. urllib.error module defines the exception classes for exceptions raised by urllib.request, urllib.parse module defines a standard interface to break Uniform Resource Locator (URL) strings up in components and urllib.robotparser provides a single class, RobotFileParser, which answers questions about whether or not a particular user agent can fetch a URL on the Web site that published the robots.txt file.