Node.js - Request Object

The req object represents the HTTP request and has properties for the request query string, parameters, body, HTTP headers, and so on.

Request Object Properties

Following is the list of few properties associated with request object.

Sr.No.	Properties & Description
1	req.app This property holds a reference to the instance of the express application that is using the middleware.
2	req.baseUrl The URL path on which a router instance was mounted.
3	req.body Contains key-value pairs of data submitted in the request body. By default, it is undefined, and is populated when you use body-parsing middleware such as body-parser
4	req.cookies When using cookie-parser middleware, this property is an object that contains cookies sent by the request.
5	req.fresh Indicates whether the request is "fresh." It is the opposite of req.stale.
6	req.hostname Contains the hostname from the "Host" HTTP header.
7	req.ip The remote IP address of the request.
8	req.ips When the trust proxy setting is true, this property contains an array of IP addresses specified in the “X-Forwarded-For” request header.
9	req.originalUrl This property is much like req.url; however, it retains the original request URL, allowing you to rewrite req.url freely for internal routing purposes.
10	req.params An object containing properties mapped to the named route “parameters”. For example, if you have the route /user/:name, then the "name" property is available as req.params.name. This object defaults to {}.
11	req.path Contains the path part of the request URL.
12	req.protocol The request protocol string, "http" or "https" when requested with TLS.
13	req.query An object containing a property for each query string parameter in the route.
14	req.route The currently-matched route, a string.
15	req.secure A Boolean that is true if a TLS connection is established.
16	req.signedCookies When using cookie-parser middleware, this property contains signed cookies sent by the request, unsigned and ready for use.
17	req.stale Indicates whether the request is "stale," and is the opposite of req.fresh.
18	req.subdomains An array of subdomains in the domain name of the request.
19	req.xhr A Boolean value that is true if the request’s "X-Requested-With" header field is “XMLHttpRequest”, indicating that the request was issued by a client library such as jQuery.

Request Object Methods

req.accepts(types)

req.accepts(types)

This method checks if the specified content types are acceptable, based on the request’s Accept HTTP header field. Following are a few examples −

// Accept: text/html
req.accepts('html');
// => "html"

// Accept: text/*, application/json
req.accepts('html');

// => "html"
req.accepts('text/html');
// => "text/html"

req.get(field)

req.get(field)

This method returns the specified HTTP request header field. Following are a few examples −

req.get('Content-Type');
// => "text/plain"

req.get('content-type');
// => "text/plain"

req.get('Something');
// => undefined

req.is(type)

req.is(type)

This method returns true if the incoming request’s "Content-Type" HTTP header field matches the MIME type specified by the type parameter. Following are few a examples −

// With Content-Type: text/html; charset=utf-8
req.is('html');
req.is('text/html');
req.is('text/*');
// => true

req.param(name [, defaultValue])

req.param(name [, defaultValue])

This method returns the value of param name when present. Following are few examples −

// ?name=tobi
req.param('name')
// => "tobi"

// POST name=tobi
req.param('name')
// => "tobi"

// /user/tobi for /user/:name 
req.param('name')
// => "tobi"

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