What is middleware in Node Js

Middleware is a function that is executed by the server before processing a client’s request. Middleware functions are often used to perform tasks such as authentication, logging, and serving static files.

Middleware in Nodejs

In Node.js, middleware functions are typically added to a server by calling the app.use() method on the Express application object. This method takes the middleware function as an argument and adds it to the middleware stack for the application.

When a client makes a request to the server, the middleware functions are executed in the order in which they were added to the stack. Each middleware function has the option of executing any code, sending a response to the client, or calling the next middleware function in the stack.

For example, consider the following middleware function that logs the current time for every request:

app.use((req, res, next) => {
     console.log(Request received at            ${Date.now()});

In this example, the middleware function logs the current time when a request is received, then calls the next() function to pass control to the next middleware function in the stack.

One of the key benefits of using middleware in Node.js is that it allows developers to modularize their code and reuse middleware functions across different parts of their application. For example, a middleware function that performs authentication can be used in multiple routes to ensure that only authenticated users can access certain resources.

In addition to the built-in middleware provided by the Express framework, developers can also create and use their own custom middleware functions. This allows them to add custom functionality to their Node.js applications and to better tailor the server’s behavior to their specific needs.

Overall, middleware is a powerful concept in Node.js that allows developers to easily add custom functionality to their servers and to better manage the flow of requests and responses.

Hey folks, this article has been written by Chat GPT3 AI. I hope you liked it.

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