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Method description (v1)


This JavaScript API is considered outdated, we recommend using API version 2

Note that some methods require the yield keyword.

yield this.request()

yield this.request(method, url, queryParams, opts)

Getting an HTTP response for a request, with the following arguments:

  • method - request method (GET, POST...)
  • url - request link
  • queryParams - hash with GET parameters or hash with POST request body
  • opts - hash with request options

If the POST method is used, the request body can be passed in two ways:

  • simply by listing the variable names and their values in queryParams. For example:
key: set.query,
id: 1234,
type: 'text'
  • through the body variable in opts. For example:
body: 'key=' + set.query + '&id=1234&type=text'


check_content: [ condition1, condition2, ...] - an array of conditions for checking the received content, if the check fails, the request will be repeated with a different proxy.


  • using strings as conditions (search by substring)
  • using regular expressions as conditions
  • using your own verification functions, which receive data and response headers
  • you can specify several different types of conditions at once
  • for logical negation, put the condition in an array, i.e. check_content: ['xxxx', [/yyyy/]] means that the request will be considered successful if the received data contains the substring xxxx and at the same time the regular expression /yyyy/ does not find matches on the page

All specified checks must pass for a successful request.

Example (the comments indicate what is needed for the request to be considered successful):

let response = yield this.request('GET', set.query, {}, {
check_content: [
/<\/html>|<\/body>/, //на полученной странице должно сработать это регулярное выражение
['XXXX'], //на полученной странице не должно быть этой подстроки
'</html>', //на полученной странице должна быть такая подстрока
(data, hdr) => {
return hdr.Status == 200 && data.length > 100;
} //эта функция должна вернуть true


decode: 'auto-html' - automatic detection of encoding and conversion to utf8

Possible values:

  • auto-html - based on headers, meta tags and page content (optimal recommended option)
  • utf8 - indicates that the document is in utf8 encoding
  • <encoding> - any other encoding


headers: { ... } - hash with headers, header name is specified in lowercase, you can specify cookie as well Example:

headers: {
accept: 'image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8',
'accept-encoding': 'gzip, deflate, br',
cookie: 'a=321; b=test',
'user-agent' 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.150 Safari/537.36'


headers_order: ['cookie', 'user-agent', ...] - allows you to override the order of header sorting


recurse: N - the maximum number of redirects, by default 7, use 0 to disable redirects


proxyretries: N - the number of attempts to execute a request, by default taken from the parser settings


parsecodes: { ... } - a list of HTTP response codes that the parser will consider successful, by default taken from the parser settings. If you specify '*': 1 then all responses will be considered successful. Example:

parsecodes: {
200: 1,
403: 1,
500: 1


timeout: N - response timeout in seconds, by default taken from the parser settings


do_gzip: 1 - determines whether to use compression (gzip/deflate/br), enabled by default (1), to disable, set the value to 0


max_size: N - maximum response size in bytes, by default taken from the parser settings


cookie_jar: { ... } - hash with cookies.


attempt: N - indicates the current attempt number, when using this parameter, the built-in handler for attempts for this request is ignored


browser: 1 - automatic emulation of browser headers (1 - enabled, 0 - disabled)


use_proxy: 1 - overrides the use of a proxy for a separate request inside the JS parser on top of the global Use proxy parameter (1 - enabled, 0 - disabled)


noextraquery: 0 - disables adding Extra query string to the request URL (1 - enabled, 0 - disabled)


save_to_file: file - allows you to download the file directly to disk, bypassing memory recording. Instead of file, specify the name and path under which to save the file. When using this option, everything related to data is ignored (checking content in check_content, will be empty, etc.).


data_as_buffer: 0 - determines whether to return data as a String (0) or as a Buffer object (1), by default a String is returned


bypass_cloudflare: 0 - automatic bypass of CloudFlare JavaScript protection using the Chrome browser (1 - enabled, 0 - disabled)


follow_meta_refresh: 0 - allows you to follow redirects declared via the HTML meta tag:

<meta http-equiv="refresh" content="time; url=..." />


tlsOpts: { ... } – allows you to pass settings for https connections ​

yield this.parser.request()

yield this.parser.request(parser, preset, overrideParams, query)

Receiving results from another scraper (built-in or another JS scraper), the following arguments are specified:

  • parser - scraper name (SE::Google, JS::Custom::Example)
  • preset - preset of the called scraper
  • overrideParams - hash with overrides of the settings of the called scraper
  • query - query

In overrideParams, you can override the parameters of the called scraper, and the following flags are also available:


resultArraysWithObjects: 0 - determines in what form to return arrays of results of the called scraper:

  • if enabled (1) - arrays of objects will be returned
    [{link: 'link1', anchor: 'anchor1'}, {link: 'link2', anchor: 'anchor2'}, ...]
  • if disabled (0) - standard arrays of values will be returned
    ['link1', 'anchor1', 'link2', 'anchor2', ...]


needData: 1 - determines whether to pass (1) or not (0) data/pages[] in the response, can be used for optimization


Global object tools, allows access to built-in A-Parser functions (analog of template toolkit tools $tools.*).


tools.query is not available, use this.query instead


Shows whether task logging is enabled, can be used as a flag for optimization, for cases when logging is not enabled and a complex expression is passed as an argument to this.logger.put



this.logger.put(message) - adds a line message to the task log


this.logger.putHTML(code) - output of HTML code to the task log, which will be displayed in the textarea

yield this.sleep()

yield this.sleep(sec)

Sets a delay in the thread for the number of seconds sec, can be fractional.

yield this.mutex.*

Mutex for synchronization between threads, allows you to block a section of code for one thread


Waiting for the lock, execution will continue for the first thread that captured the lock, other threads will wait for the lock to be released


Releasing the lock, the next thread will continue execution if it was waiting for the lock(.lock())


Working with cookies for the current request


Getting an array of cookies


Setting cookies, an array with cookies must be passed as an argument


this.cookies.set(host, path, name, value) - setting a single cookie


this.query.add(query, maxLvl)

Adding a new query (query) with the ability to optionally specify the maximum level (maxLvl), similar to tools.query.add() You can pass a hash with parameters as a query (query), works similarly to Query Builder


query: "",
param1: "..",


Working with proxies


Switch to the next proxy, the old proxy will no longer be used for the current request


Switch and ban the proxy (must be used when the service blocks work by IP), the proxy will be banned for the time specified in the parser settings (proxybannedcleanup)


Get the current proxy (the last proxy with which the request was made)


this.proxy.set('', noChange = false) - set the proxy for the next request, the noChange parameter is optional, if set to true, the proxy will not change between attempts

yield this.captcha.*

Working with captcha


yield this.captcha.recognize(preset, image, type, overrides) - loading a captcha for recognition

  • image - binary image data for recognition
  • preset - specifies the preset for Util::AntiGateUtil::AntiGate
  • type is specified as one of: 'jpeg', 'gif', 'png'

The result will be a hash with fields:

  • answer - text from the image
  • id - captcha id, for the possibility of reporting an error through reportBad
  • error - text error, if answer is not set


yield this.captcha.recognizeFromUrl(preset, url, overrides) - similar to the previous method, but the captcha will be loaded automatically by link (url), without using a proxy


yield this.captcha.reportBad(preset, id, overrides) - report to the service that the captcha was recognized incorrectly



this.utils.updateResultsData(results, data) - a method for automatically filling $pages.$ and $data, must be called to add content to the resulting page


this.utils.urlFromHTML(url, base) - processes the link obtained from HTML code - decodes entities (&amp; etc.), optionally you can pass base - the base URL (for example, the URL of the source page), thus the full link can be obtained


this.utils.url.extractDomain(url, removeDefaultSubdomain) - the method takes a link as the first parameter and returns the domain from this link. The second optional parameter determines whether to remove the www subdomain from the domain. By default, 0 - i.e. not to remove.


this.utils.url.extractTopDomain(url) - the method takes a link as the first parameter and returns the domain from this link, without subdomains.


this.utils.url.extractTopDomainByZone(url) - the method takes a link as the first parameter and returns the domain from this link, without subdomains including regional zones.


this.utils.url.extractMaxPath(url) - the method takes a string and selects a URL from it.


this.utils.url.extractWOParams(url)- the method takes a link and returns the same link truncated to the parameter string. That is, it will return the URL up to ?


this.utils.removeHtml(string) - the method takes a string and returns it cleared of html tags.


this.utils.removeNoDigit(string) - the method takes a string, removes everything except digits from it, and returns the result.


this.utils.removeComma(string) - the method takes a string, removes characters such as .,\r\n from it, and returns the result.


To use sessions in a JS scraper, you first need to initialize the session manager. This is done using the init() function.

init() {
//здесь можно задать дополнительные параметры

In this.sessionManager.init(), you can use the following parameters:

  • name - optional parameter, allows you to override the name of the scraper to which the sessions belong, by default it is equal to the name of the scraper in which the initialization takes place
  • canChangeProxy - optional parameter, the ability to change the proxy, by default it is equal to 1
  • domain - optional parameter, specifies to search for sessions among all saved for this scraper (if the value is not set), or only for a specific domain (you need to specify the domain with a dot in front, for example

There are several functions for working with sessions:


this.sessionManager.get() - gets a new session, must be called before making a request.


this.sessionManager.reset() - clears cookies and gets a new session. It must be called if the request with the current session was unsuccessful.

.save() - saves a successful session or saves arbitrary data in the session.


The results.<array>.addElement() method allows you to fill arrays in results more conveniently. When using it, you do not need to remember the sequence of variables in the array and list them manually.

link: '',
anchor: 'Google',
snippet: 'Loreps ipsum...',

init() and destroy() methods

The init() method is called at the start of the task, destroy() - at the end.

Example of use:

const puppeteer = require("puppeteer");
let globalBrowser;

class Parser {
constructor() {

async init() {
globalBrowser = await puppeteer.launch();

async destroy() {
await globalBrowser.close();

Example of saving a file to disk

An example demonstrating how to save files directly to disk

Example of working with sessions

Using session functionality in JavaScript scrapers

Example of saving data in a session

Demonstration of the ability to store arbitrary data in a session

Using results.addElement()

An example of filling an array of data using results.addElement() and demonstrating the difference from regular .push()