How do I use Morgan logging middleware in my Express app?

How do I use Morgan logging middleware in my Express app?

To use Morgan in your Express app, first install it using npm: npm install morgan. Then, require it in your app and use it as middleware.

Can you show me a code example?

Sure! Here's a simple example:

const express = require('express');
const morgan = require('morgan');

const app = express();

app.use(morgan('tiny'));

app.get('/', (req, res) => {
  res.send('Hello World!');
});

app.listen(3000, () => {
  console.log('Server is running on port 3000');
});

What are the different formats I can use with Morgan?

Morgan provides several predefined formats like 'combined', 'common', 'dev', 'short', and 'tiny'. You can also create a custom format.

How can I log to a file instead of the console?

You can use the fs module to create a write stream and pass it to Morgan. Here's an example:

const fs = require('fs');
const path = require('path');
const morgan = require('morgan');

const app = express();
const accessLogStream = fs.createWriteStream(path.join(__dirname, 'access.log'), { flags: 'a' });

app.use(morgan('combined', { stream: accessLogStream }));