Request Object in Node.js: What You Need to Know

The req object represents the HTTP Request and has properties for the request query string, parameters, body, HTTP Header,.

Before entering the chapter, you will learn what the middleware concept is:

Properties of the Request object in Node.js

The table below lists some commonly used properties of the Request object in Node.js:

Stt Properties & Description1 req.app This property holds a reference to the Express application using Middleware 2 req.baseUrl The URL link on which a router is mounted 3 req.body Contains key-value pairs of data submitted in the body section of the Request. By default, it is undefined, and is generated when you use a Middleware to parse the body of the request ( body-parser example) 4 req.cookies When using cookie-parser middleware, this attribute is an object that contains Cookies sent by Request 5 req.fresh Determine whether or not Request is "fresh." This attribute is in contrast to req.stale. 6 req.hostname Contains the hostname section from the "Host" section of the HTTP header. 7 req.ip Remote IP address of the request. 8 req.path Contains the path part of the URL in the Request. 9 req.protocol The protocol string of Request, which is "http" or "https" when requested with TLS 10 req.query An object contains an attribute for each query string parameter in Router 11 req.route A string representing the current route is connected to 12 req.secure Is true if a TLS connection is successfully established 13 req.signedCookies When using cookie-parser Middleware, this property contains Cookies sent by Request 14 req.stale Determining whether or not Request is "stale", this attribute is in contrast to the req.fresh attribute. 15 req.subdomains An array consists of subdomains in the domain name section of the Request

Method of Request object in Node.js

Method req.accepts (types)

 req . accepts ( types ) 

This method checks whether the Content-type is acceptable, based on the Request HTTP Header field of the Request. For instance,:

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

Method req.get (field)

 req . get ( field ) 

This method returns the specific Header field of the Request. For instance,:

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

Method req.is (type)

 req . is ( type ) 

This method returns true if the Content-Type field of the Request is connected to the Type MIME type specified by the type parameter. For instance,:

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

Req.param method (name [, defaultValue])

 req . param ( name [, defaultValue ]) 

Next lesson: Response object in Node.js