Website Scraping

What is site scraping?
In simple terms, parsing is an automated collection of information from any site, its analysis, transformation and presentation in a structured form, most often in the form of a table with a data set.

A site parser is any program or service that automatically collects information from a given resource.

In the article we will analyze the most popular programs and services for web scraping.

Why is parsing needed and when is it used?

In general, parsing can be divided into 2 types:

Technical site parsing, which is mainly used by SEO specialists to identify various site problems:
Search for broken links and incorrect 30* redirects.
Identification of duplicates or other problems with Title, Description meta tags and h1 headings.
To analyze the correct operation of Robots.txt.
Checking the microdata settings on the site.
Detection of unwanted pages that are open for indexing.
Other technical tasks.
Based on the data obtained, the specialist draws up technical specifications to eliminate the identified problems.

Website parsing for business development. Here are some examples of such tasks:
Collection of information about the range of competitors.
Parsing product names, SKUs, prices and other things to fill your own online store. This can be either a one-time task or based on regular monitoring.
Analysis of the structure of competitor sites in order to improve and develop their own structure.
The main examples of using parsing are listed above. In fact, there are much more of them and is limited only by your imagination and some technical features.

How does parsing work? Parser algorithm.

The parsing process is the automatic extraction of a large amount of data from web resources, which is performed using special scripts.

In short, the parser follows the links of the specified site and scans the code of each page, collecting information about it in an Excel file or somewhere else. The totality of information from all pages of the site will be the result of the site parsing.

Parsing works on the basis of XPath queries, it is a language that refers to a specific section of the page code and extracts information specified by the criterion from it.

Algorithm for standard site parsing.

Search for the necessary data in its original form.
Data extraction with separation from program code.
Formation of the report according to the requirements that have been set.
Why is parsing better than human work?
Website scraping is a routine and time-consuming job. If manually extracting information from a site with only 10 pages is not such a difficult task, then analyzing a site with 50 pages or more will no longer seem so easy.

In addition, the human factor cannot be excluded. A person may not notice or attach importance to something. In the case of the parser, this is excluded, the main thing is to configure it correctly.

In short, the parser allows you to quickly, efficiently and structured to get the necessary information.

What information can be obtained using the parser?

Different parsers may have their own limitations on parsing, but in essence you can parse and get absolutely any information that is in the code of the site pages.