Adding Error Handling Middleware in Express JS

Error Handling is crucial for a robust application. Express provides a way to catch errors thrown in your application code or middleware. Here’s an example of error handling middleware:

Javascript
app.use((err, req, res, next) => {
  console.error(err.stack); // Log the error for debugging
  res.status(500).send('Internal Server Error'); // Send a generic error response
});

This middleware is a catch-all for any errors that haven’t been handled by specific route handlers. It logs the error and sends a generic error response to the client.

Place error handling middleware at the bottom of your app.use() chain, after all other middleware and route handlers, so it catches unhandled errors. Consider providing more specific error messages for different error types in a production environment.

By implementing middleware effectively, you can streamline common tasks, improve the maintainability of your code, and create a more robust and user-friendly web application.



Getting Started with Express JS

Express JS is a versatile, minimalist web framework for NodeJS that simplifies the development of back-end applications and APIs for web and mobile applications. Its flexibility and powerful features enable you to create robust and scalable web projects with minimal code, making it a popular choice among developers. Express is released as free and open-source software under the MIT License.

Table of Content

  • Installing Express JS
  • Running a simple web server in Express JS
  • Adding Routes for Handling request in Express JS
  • Adding Parameters to Routes in Express JS
  • Modularizing Routes with Express Router:
  • Adding Middleware for Processing Requests in Express JS
  • Adding Error Handling Middleware in Express JS

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Running a simple web server in Express JS:

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Adding Parameters to Routes in Express JS:

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Modularizing Routes with Express Router:

As your application grows, managing routes in a single file can become cumbersome. Express Router allows you to create modular route handlers:...

Adding Middleware for Processing Requests in Express JS:

Middleware are functions that have access to incoming requests and outgoing responses in your Express application. They allow you to perform common tasks across multiple routes or the entire application, such as logging, authentication, and error handling....

Adding Error Handling Middleware in Express JS:

Error Handling is crucial for a robust application. Express provides a way to catch errors thrown in your application code or middleware. Here’s an example of error handling middleware:...