express middleware logging

Express middleware logging is a feature in the Express framework that allows developers to log information about incoming requests and outgoing responses. It provides valuable insights into the flow of the application and helps in debugging and monitoring.

Here are the steps involved in implementing express middleware logging:

Import the necessary modules: To enable logging in Express, you need to import the required modules. One commonly used module is morgan, which provides a pre-configured middleware for logging HTTP requests.
Create a logging middleware function: Next, you need to define a middleware function that will handle the logging. This function will have access to the request (req), response (res), and the next middleware function in the chain (next). It can log information such as the request method, URL, response status, and response time.
Configure the logging middleware: Once the logging middleware function is defined, you need to configure it to be used in your Express application. This is done by adding it as a middleware using the app.use() method. The logging middleware should be added before any other middleware or route handlers, so that it can log the requests and responses in the correct order.
Customize the logging format (optional): By default, the morgan module provides a predefined logging format. However, you can customize the format according to your needs. This can be done by passing a format string to the morgan middleware function. The format string can include placeholders for various request and response properties.
Start the Express server: Finally, start your Express server and observe the logging output in the console or log files. You should see log entries for each incoming request, including details such as the request method, URL, response status, and response time.

By following these steps, you can easily implement express middleware logging in your Express application and gain valuable insights into the request-response flow.