Express.js App Set Method

The app.set() function assigns or sets a setting name to value. This can store any type of value as the user wants, but there are some certain names that can be used to configure the behaviour of the server

Some of the properties that can be configured with the set functionality are −

• env

• etag

• jsonp escape,etc

Syntax

app.set(name, value)

Example 1

Create a file with the name "appSet.js" and copy the following code snippet. After creating the file, use the command "node appSet.js" to run this code.

// app.set() Demo Example

// Importing the express module
var express = require('express');

// Initializing the express and port number
var app = express();
var PORT = 3000;

// Setting the value to name
app.set('title', 'Welcome to TutorialsPoint');

// Creating an endpoint
app.get('/', (req, res) => {
   res.send(app.get('title'));
   console.log(app.get('title'));
})

app.listen(PORT, function(err){
   if (err) console.log(err);
   console.log("Server listening on PORT", PORT);
});

Now, hit the following endpoint/api to call the function

• GET http://localhost:3000/

Output

C:\home
ode>> node appSet.js
Server listening on PORT 3000
Welcome to TutorialsPoint

Example 2

Let’s take a look at one more example.

// app.set() Demo Example

// Importing the express module
var express = require('express');

// Initializing the express and port number
var app = express();
var PORT = 3000;

// Setting the value to name
app.set('title', 'Hi, The requested page is not available');

// Creating an endpoint
app.get('/*', (req, res) => {
   res.send(app.get('title'));
   console.log(app.get('title'));
})

app.listen(PORT, function(err){
   if (err) console.log(err);
   console.log("Server listening on PORT", PORT);
});

For the above function, you can call any endpoint after '/' and it will be passed through the above function only. For example

• http://localhost:3000/api,

• http://localhost:3000/,

• http://localhost:3000/path, etc.

Output

C:\home
ode>> node appRoute.js
Server listening on PORT 3000
Hi, The requested page is not available