The `querystring` module provides utilities for parsing and formatting URL

query strings. It can be accessed using:

const querystring = require('querystring');

* `str` {String}

The `querystring.escape()` method performs URL percent-encoding on the given

`str` in a manner that is optimized for the specific requirements of URL

query strings.

The `querystring.escape()` method is used by `querystring.stringify()` and is

generally not expected to be used directly. It is exported primarily to allow

application code to provide a replacement percent-encoding implementation if

necessary by assigning `querystring.escape` to an alternative function.

* `str` {String} The URL query string to parse

* `sep` {String} The substring used to delimit key and value pairs in the

query string. Defaults to `'&'`.

* `eq` {String}. The substring used to delimit keys and values in the

query string. Defaults to `'='`.

* `options` {Object}

* `decodeURIComponent` {Function} The function to use when decoding

percent-encoded characters in the query string. Defaults to

`querystring.unescape()`.

* `maxKeys` {number} Specifies the maximum number of keys to parse.

Defaults to `1000`. Specify `0` to remove key counting limitations.

The `querystring.parse()` method parses a URL query string (`str`) into a

collection of key and value pairs.

For example, the query string `'foo=bar&abc=xyz&abc=123'` is parsed into:

{

foo: 'bar',

abc: ['xyz', '123']

}

*Note*: The object returned by the `querystring.parse()` method _does not_

prototypically extend from the JavaScript `Object`. This means that the

typical `Object` methods such as `obj.toString()`, `obj.hashOwnProperty()`,

and others are not defined and *will not work*.

By default, percent-encoded characters within the query string will be assumed

to use UTF-8 encoding. If an alternative character encoding is used, then an

alternative `decodeURIComponent` option will need to be specified as illustrated

in the following example:

* `obj` {Object} The object to serialize into a URL query string

* `sep` {String} The substring used to delimit key and value pairs in the

query string. Defaults to `'&'`.

* `eq` {String}. The substring used to delimit keys and values in the

query string. Defaults to `'='`.

* `options`

* `encodeURIComponent` {Function} The function to use when converting

URL-unsafe characters to percent-encoding in the query string. Defaults to

`querystring.escape()`.

given `obj` by iterating through the object's "own properties".

For example:

By default, characters requiring percent-encoding within the query string will

be encoded as UTF-8. If an alternative encoding is required, then an alternative

`encodeURIComponent` option will need to be specified as illustrated in the

following example:

* `str` {String}

The `querystring.unescape()` method performs decoding of URL percent-encoded

characters on the given `str`.

The `querystring.unescape()` method is used by `querystring.parse()` and is

generally not expected to be used directly. It is exported primarily to allow

application code to provide a replacement decoding implementation if

necessary by assigning `querystring.unescape` to an alternative function.

JavaScript built-in `decodeURIComponent()` method to decode. If that fails,

a safer equivalent that does not throw on malformed URLs will be used.