What Is Site Parsing and What's It For?

Parsing (web scraping) is an automated collection of open information on the Internet according to specified conditions. Data can be parsed from websites, search results, forums and social networks, portals and aggregators. In this article we will deal with parsers of sites.

It is often necessary to obtain and analyze a large amount of technical and commercial information posted on your projects or competitors' sites. Parsers are indispensable for collecting such data - programs or services that "pull out" the necessary information and present it in a structured form.

Who needs site parsers and why?

Parsers save time on collecting large amounts of data and grouping them into the right form. Such services are used by Internet marketers, webmasters, SEO-specialists, and employees of sales departments.

Parsers can perform the following tasks:

• Collection of prices and assortment. This is useful for online stores. Using the parser, you can monitor competitors' prices and fill out a catalog on your resource in automatic mode.
• Parsing the metadata of the site (title, description, H1 headings) is useful for SEO specialists.
• Analysis of technical optimization of the resource (broken links, 404 errors, non-working redirects, etc.) will need SEO specialists and webmasters.
• Programs for downloading whole sites or parsers of content (texts, images, links) are in the "gray" zone. With their help unscrupulous webmasters clone sites for the subsequent sale of links from them.

Who and for what purposes require parsers, figured out. If you need this tool, there are several ways to get it.

1. If you have programmers on staff, the easiest way is to ask them to create a parser for the desired purpose. This gives you flexibility and responsive tech-support. The most popular languages for creating parsers - PHP and Python. 
2. Use a free or paid cloud service. 
3. Set up a program that is suitable in terms of functionality.
4. Contact a company that will develop a tool for your needs (the most expensive option, as expected).

With the first and last options, everything is clear. But choosing from ready-made solutions can take much time. We made this task easy and reviewed the tools.

Classification of Parsers

Parsers can be classified according to various criteria.

1. By the method of access to the interface: cloud solutions and programs that require installation on the computer. 
2. By technology: parsers based on programming languages (Python, PHP), extensions for browsers, add-ons in Excel, formulas in Google tables.
3. According to their purpose: monitoring competitors, collecting data in a particular niche market, parsing products and prices to fill the catalog of online stores, parsers data social networks (communities and users), checking the optimization of your resource.

Let's analyze parsers on different grounds, and dwell on parsers by appointment.
Parsers sites by the method of access to the interface

Cloud parsers

Cloud services do not require installation on a PC. All data is stored on the servers of the developers, you download only the result of parsing. The software is accessed through a web interface or API.

Examples of cloud parsers 

• http://import.io/
• Mozenda (there is also software to install on your computer);
• Octoparce;
• ParseHub;

Site parsers depending on the tasks they solve

In order not to make a mistake when choosing a parsing software or cloud service, you need to understand the range of tasks they solve. We have divided parsers by their areas of application.
Parsers for Joint Purchases (JV) Organizers

The separate category of parsers is intended for those who are engaged in the organization of joint purchases in the social networks VKontakte and Odnoklassniki. The owners of JV groups buy batches of goods in small bulk at a price cheaper than the retail price. To do this, you need to constantly monitor the assortment and prices on the sites of suppliers. To reduce labor costs, you can use specialized parsers.

Such parsers have a simple, intuitive control panel interface, where you can specify the necessary settings - pages for parsing, schedule, groups in social networks for unloading and others.

Examples of services:

• Turbo.Parser;
• Q-Parser;
• Cloud parser;

Services for competitor monitoring

This group of parsers allows the prices in the online store to remain at the level of the market. These services monitor selected resources, compare products and their prices to your catalog and provide an opportunity to adjust the price to a more attractive one. Such parsers monitor competitors' sites, updated price lists in XLS(X), CSV and other formats, marketplaces (Yandex.Market, e-katalog and other price aggregators).

Examples of competitor price parsers:

• Marketparser, 
• Xmldatafeed,  
• ALL RIVAL.

Data collection and autofilling with content

These parsers simplify the work of online store content managers by replacing manual monitoring of suppliers' websites, comparing and changing assortments, descriptions and prices. The parser collects data from suppliers' sites (product names and descriptions, prices, images, etc.) and uploads it to a file or directly to the site. The settings have the ability to make a markup, to combine data from multiple sites, to run data collection in automatic mode on a schedule or manually.

Examples of parsers for filling online stores:

• Catalogloader,  
• Xmldatafeed

How to choose a parser

1. Determine the purpose of the parsing: monitoring competitors, filling the directory, checking SEO parameters, combining several tasks.   
2. Find out how much data and in what form you need to get in the output. 
3. Think about how regularly you need to collect and process data: once a month, every day?
4. If you have a large resource with complex functionality, it makes sense to order the creation of a parser with flexible settings for your purposes. There are sufficient off-the-shelf solutions for standard projects on the market.
5. Choose several tools and read the reviews. Pay special attention to the quality of technical support.   
6. Correlate the level of your or the person responsible for the data with the complexity of the tool.
7. Based on the above parameters, choose the appropriate tool and tariff. Perhaps, free functionality or a trial period will be enough for your tasks.