header-generator

Header generator

NodeJs package for generating browser-like headers.

• Installation
• Usage
• Result example
• API Reference

Installation

Run the npm install header-generator command. No further setup is needed afterwards.

Usage

To use the generator, you need to create an instance of the HeaderGenerator class which is exported from this package. Constructor of this class accepts a HeaderGeneratorOptions object, which can be used to globally specify what kind of headers you are looking for:

const HeaderGenerator = require('header-generator');
let headerGenerator = new HeaderGenerator({
        browsers: [
            {name: "firefox", minVersion: 80},
            {name: "chrome", minVersion: 87},
            "safari"
        ],
        devices: [
            "desktop"
        ],
        operatingSystems: [
            "windows"
        ]
});

You can then get the headers using the getHeaders method, either with no argument, or with another HeaderGeneratorOptions object, this time specifying the options only for this call (overwriting the global options when in conflict) and using the global options specified beforehands for the unspecified options:

let headers = headersGenerator.getHeaders({
        operatingSystems: [
            "linux"
        ],
        locales: ["en-US", "en"]
});

This method always generates a random realistic set of headers, excluding the request dependant headers, which need to be filled in afterwards. Since the generation is randomized, multiple calls to this method with the same parameters can generate multiple different outputs.

Result example

A result that can be generated for the usage example above:

{
  "sec-ch-ua-mobile": "?0",
  "user-agent": "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.72 Safari/537.36",
  "accept-encoding": "gzip, deflate, br",
  "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9",
  "upgrade-insecure-requests": "1",
  "accept-language": "en-US,en;0.9",
  "sec-fetch-site": "same-site",
  "sec-fetch-mode": "navigate",
  "sec-fetch-user": "?1",
  "sec-fetch-dest": "document"
}

API Reference

All public classes, methods and their parameters can be inspected in this API reference.

HeaderGenerator

HeaderGenerator randomly generates realistic browser headers based on specified options.

• HeaderGenerator
  • new HeaderGenerator(options)
  • .getHeaders(options, requestDependentHeaders)

---

new HeaderGenerator(options)

Param	Type	Description
options	HeaderGeneratorOptions	default header generation options used unless overridden

---

headerGenerator.getHeaders(options, requestDependentHeaders)

Generates a single set of headers using a combination of the default options specified in the constructor and their possible overrides provided here.

Param	Type	Description
options	HeaderGeneratorOptions	specifies options that should be overridden for this one call
requestDependentHeaders	Object	specifies known values of headers dependent on the particular request

---

BrowserSpecification

Param	Type	Description
name	string	One of chrome, firefox and safari.
minVersion	number	Minimal version of browser used.
maxVersion	number	Maximal version of browser used.
httpVersion	string	Http version to be used to generate headers (the headers differ depending on the version). Either 1 or 2. If none specified the httpVersion specified in HeaderGeneratorOptions is used.

---

HeaderGeneratorOptions

Param	Type	Description
browsers	Array.<(BrowserSpecification|string)>	List of BrowserSpecifications to generate the headers for, or one of chrome, firefox and safari.
operatingSystems	Array.<string>	List of operating systems to generate the headers for. The options are windows, macos, linux, android and ios.
devices	Array.<string>	List of devices to generate the headers for. Options are desktop and mobile.
locales	Array.<string>	List of at most 10 languages to include in the Accept-Language request header in the language format accepted by that header, for example en, en-US or de.
httpVersion	string	Http version to be used to generate headers (the headers differ depending on the version). Can be either 1 or 2. Default value is 2.

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