Nowadays the information is updating very quickly. It’s difficult to process it manually and it takes a lot of time, you can miss the essential point. Therefore, special programs such as parser have been created. They automatically analyze and collect data of interest, cope with the huge arrays of constantly changing information.
What is the parser
Parser is a program or a search engine (a grabber or a script) that carries out the analysis of information on the website pages. It organizes a data collection (parses) and structures it. The parser provides a syntactic analysis of the text information on mathematical model, by which tokens are compared with formal grammar.
The same can be described as the action of a person when reading words, namely, the tokens. He also parses, that is the comparison of read words with those which he has in his vocabulary or with formal grammar.
Such programs are widely used. They differ in their purpose of work, but they share the same principle. The information is collected according to a given topic. As a result you get data which is used for your intended purpose.
What parser is used for
Collection and analysis of information on the Internet takes a long time, effort and resources. Automated parser program is able to cope with such task faster and easier. In 24 hours it can scour a huge amount of the web content in the Internet, searching for and analyzing the appropriate data you need.
Search engine robots, uniqueness testing programs are doing this. In speed mode, they analyze hundreds of web pages that contain a similar text.
Accordingly, using the parser program you can find a content for infilling your own web site.
It’s possible to parse a content of the following types:
• lists of goods, their properties, photos and description, texts;
• web pages with mistakes (such as 404, the absence of Title, etc);
• the value of goods from competitors;
• level of user activity (likes, comments, reposts);
• potential audience for an advert and promotion of goods and services.
The parser is widely used by the owners of online stores to parse the content for infilling the product cards. The descriptions of those cards are not the intellectual property, but it takes a lot of time and effort to make them.
The parser allows you to solve the following tasks:
• The possibility to parse a large volume of data. An increasing competition requires to process and put a huge amount of information on your web resources. But it isn’t possible to manually overpower such volume of content.
• Constant updating of content. One person or even an entire team of operators can’t service a rich flow of information that is constantly changing. Data changes every minute, therefore, it’s impossible to do this in manual operation.
• Using of this program is a modern and efficient way to parse the content automatically with its constant updating.
The advantages of parser use are:
• Speed of operation. Hundreds of web resources are browsed in seconds.
• Accuracy. Parser systemizes the information on technical and “human”.
• Error-free operation. Script highlights only the information you need.
• Efficiency. Parser will bring the data to required form.
Parser implements a comparative analysis of the given words with all the words that were found on the Internet. The program works according to the proposed algorithm. Task (what to do with the information) is written in the command line where the words and their combinations, letters, program syntax characters are specified. The creation of a parser is possible in any programming languages but, above all, they must maintain “regular expressions”. This is a command line, in the programming parlance it is also called “a template” or “a mask”.
Regular expressions (RegExp) are a special tool for searching for the characters to match the specified template. In other words, these are special programming languages for creating line models.
Parser generates a certain sequence of characters or their structure in a line. The main task is to find only the necessary information and sort unnecessary one. It turns out that script works with the text information. It extracts the specified data and converts it into a more usable format.
The information is parsing in the following order:
• Compilation of information. A page code of the website is specified in the program. Then a parser script is required to be written for the code division into lexems, the analysis of useful information.
• Data sampling. Users don’t need all the information but just the specific one. For example, you need reviews concerning TV sets. Therefore, first, the parser finds a category with TV sets in the code page of website and after that a place for comments. As a result, only the required reviews are extracted.
• Storage of the received data. After receiving all the necessary information it is required to store it. Some organize charts as it is visually. Others build database, they are easy-to-use for analysts.
Security against a competitive parser
But such program also works in the opposite direction. That’s why no one wants somebody to surf the website and retrieve the data. As a result, initially unique articles will no longer be such unique.
Nowadays there are various security methods against the parsers:
• Division of access possibility. Information about the site structure is closed and is only accessible for the administrator.
• Time delay of the interval between requests. Due to this method the site is secured from constant chaotic queries which are sent by one machine but with different interval of signals.
• Adding users into blacklist or whitelist. Therefore, the blacklist is for infringers who have tried to copy the information and content.
• Fixation the page update time. If you set the update time in the file sitemap.xml, the competitors will find it difficult to get to them. To improve the security it is possible to limit the frequency of requests and the number of downloads.
• Security implementation against the robots. Captcha is able to handle this task very well, because only a person can enter it.
The area of use
Internet users, who have never heard of the parser, have a logical question: “Where and what it is used for?” There are many areas of parser use and they are different. In many of them, even indirectly related to the Internet, you need to parse the content. Analysis of information is used in the following cases:
• It will be useful for the owners of online stores for rapid data collection of goods and for later website infilling.
• Realtors constantly monitor advertisements for the purchase and sale of real estate. It is very tedious, long and inefficient to do this manually. Real estate parser will be useful for doing this. It concerns car dealers, etc.
• You even can use parser for the website or blog creation. It automates the information collection and can help to infill the content. It is possible to improve the uniqueness by means of synonymization or automatic translation.
• Parser support is required for search of new partners and clients. Doing this work on your own is inefficient and it takes a long time. This program automates, simplifies and speeds up the process.
• Parser would be useful in the field of activity related to SEO. Script analyzes the links from search engines, passability of the website, requests from statistical data of various sources. Scripts-parser are applied by Google or Yandex. The received information is provided in the accessible format.
• For data maintenance in the relevant mode in the fields where the information gets out of date every minute. Manual updating requires a lot of human resources. But this program can handle such task easily. The glaring examples are currency markets or weather forecasts.
• For website aggregators. They help to parse the content from different platforms and also combine it. This makes it easier for users to search the information. Script immediately tracks the updates and provides the relevant information. This includes job and news sites, online stores, etc.
The examples of website use, where the content is required to parse, are:
• Travel agencies update the information about places of resort, prices, hotel and weather conditions and tourist attractions.
• News sites collect the latest information.
• Update product information to search for the new products.
• Data retrieval in social media: from one social media the information moves to another or to the website.
• Collection of data on the list of accounts in Vkontakte with the following preservation in accessible format.
• Participants ID audience analysis of the ad hoc group for advertising. This program tracks the online activity of the subscribers.
Parser makes the life easier and it also improves the content. Reasonable use of the program will not harm the competitors, but it also brings your business on to a new level. Applying to our company you will receive a high-quality program. Our specialists will design a script in accordance with all requirements.
A parser creation
Parsers are written in different programming languages. The most popular are PHP, C++, Perl, Delphi, Ruby, Pyton. The first is being used more often due to its pros:
•existence of a library libcurl, which allows script to connect to any server, even if it works at such protocols as https, ftp, telnet;
• regular expression support;
• the existence of a library DOM, that works with XML. It is a special language for the text markup, that provides the operation results of a machine;
• compatibility with HTML.
If you need to write a parser script, then to create it you can address to:
• the random freelancer, but it is risky, because you do not know exactly if he has an experience in parser creation. In this case there is no guarantee of quality.
• the staff programmer, but there are also the same risks. Moreover, there may be no person in the company who would have an experience in the field of such activity. He may not take into account all the subtleties and features.
•theprofessionals, that is, to us. Our staff specializes in parser creation. We already have ready solutions for you, which are waiting for personal correction and refinement.
In our company the parser creation is made according to the following stages:
• Specialists receive a detailed task from the client. Then all the subtleties are being agreed and confirmed.
• A programmer starts to create a parser.
• After receiving the finished program, it needs to be tested, eliminated from bugs and configured to the correct work of a script.
• We give the whole project only after all checks, therefore you can be sure in a high-quality of the parser operation.
And in the end, you will get:
• a high-speed data processing;
• easy operation and task setting;
• efficiency in needed data collection;
• possibility to track the position in the original text.