Found 72 Articles for Express JS

The router.METHOD() is used for providing the method functionality in Express, where METHOD represents one of the HTTP methods such as GET, POST, PUT, and so on, in lowercase. Therefore, the actual methods are represented as following −router.get()router.post()router.put() …… and so on...Syntaxrouter.METHOD( path, [callback ...], callback )Example 1Create a file with the name "routerMETHOD.js" and copy the following code snippet. After creating the file, use the command "node routerMETHOD.js" to run this code as shown in the example below −// router.METHOD() Method Demo Example // Importing the express module const express = require('express'); // Initializing the express and ... Read More

The res.get() method is used to return the HTTP headers specified by the field. The match is case-insensitive and therefore returns all the matching patterns.Syntaxres.get( field )Example 1Create a file with the name "resGet.js" and copy the following code snippet. After creating the file, use the command "node resGet.js" to run this code as shown in the example below −// res.get(field) Method Demo Example // Importing the express module var express = require('express'); // Initializing the express and port number var app = express(); // Initializing the router from express var router = express.Router(); var PORT = 3000; ... Read More

req.range() is basically a range header parser. The accept-ranges and the response-header fields allow the server to indicate the acceptance of the range requests from a resource.Syntaxreq.range( size, [options])ParametersThe above parameters are defined as follows −size – The size parameter defines the maximum size of the resource.options – The options parameter can have the following properties −combine – It is a Boolean type variable. This parameter specifies if overlapping and whether the adjacent ranges should be combined or not. Default: FalseExample 1Create a file with the name "reqRange.js" and copy the following code snippet. After creating the file, use the ... Read More

The req.xhr property is a Boolean property that returns True when the request's X-Requested-With header field is "XMLHttpRequest". The True pointer basically indicates that the request was issued by a client library such as jQuery.Syntaxreq.xhrExample 1Create a file with the name "reqXhr.js" and copy the following code snippet. After creating the file, use the command "node reqXhr.js" to run this code as shown in the example below −// req.xhr Property Demo Example // Importing the express module var express = require('express'); // Initializing the express and port number var app = express(); // Initializing the router from ... Read More

The req.stale property checks whether a request is fresh or stale in the client's cache. If the property returns True, it means the client's cache is stale and all the data needs to be transferred to the client's system. Else, only the non-cached data needs to be transmitted.Syntaxreq.staleExample 1Create a file with the name "reqStale.js" and copy the following code snippet. After creating the file, use the command "node reqStale.js" to run this code as shown in the example below −// req.stale Property Demo Example // Importing the express var express = require('express'); // Initializing the express and ... Read More

The req.secure property returns a Boolean value that returns true if a TLS connection is established, else it will return False.Its logic is similar to the following method −--> req.protocol == "https"Syntaxreq.secureExample 1Create a file with the name "reqSecure.js" and copy the following code snippet. After creating the file, use the command "node reqSecure.js" to run this code as shown in the example below −// req.secure Property Demo Example // Importing the express var express = require('express'); // Initializing the express and port number var app = express(); // Initializing the router from express var router = ... Read More

The res.set() method can be used for setting the response's HTTP header field to value. You can also set multiple fields at once by passing an object as the parameter.Syntaxres.set( field, [value] )Example 1Create a file with the name "resSet.js" and copy the following code snippet. After creating the file, use the command "node resSet.js" to run this code as shown in the example below −// res.set(field, [value]) Method Demo Example // Importing the express var express = require('express'); // Initializing the express and port number var app = express(); // Initializing the router from express var ... Read More

The req.is() method is used for returning the matching content-type. It returns the matching content-type when the incoming request's "Content-type" HTTP header matches with those of the MIME type specified by the type parameter. If the request has no body, then it returns NULL, else it returns False.Syntaxreq.is( type )The type parameter takes the input for the Content-type to be matched. For example, html, text/html, text/*, etc.Example 1Create a file with the name "req.js" and copy the following code snippet. After creating the file, use the command "node req.js" to run this code as shown in the example below −// ... Read More

An application needs to maintain the remote client address for managing the number of requests from a computer system and tracking its usage. But sometimes, the server runs behind an NGINX server, so we need to check its forward request. For this purpose, we can use "x-forwarded-for"Syntaxreq.headers['x-forwarded-for'] || req.socket.remoteAddressIf the proxy isn't yours, one should be careful while using the x-forwarded-for header, because it can be spoofed.Example 1Create a file with the name "remoteAddress.js" and copy the following code snippet. After creating the file, use the command "node remoteAddress.js" to run this code as shown in the example below −// ... Read More

The res.jsonp() method sends the json response with JSONP support. This method is similar to the res.json() method with the only difference being that it provides the JSONP callback support.Syntaxres.jsonp ( [body] )Example 1Create a file with the name "resJsonp.js" and copy the following code snippet. After creating the file, use the command "node resJsonp.js" to run this code as shown in the example below −// res.jsonp([body]) Method Demo Example // Importing the express module var express = require('express'); // Initializing the express and port number var app = express(); // Initializing the router from express var ... Read More