Most developer tools built into browsers will automatically request a sourcemap file for .js and .css files that have been minified. In order prevent 404 errors showing in your express application constantly for missing .map files, use this middleware to skip HTTP requests for .map files. Don't use this module if you actually have sourcemap files for your minified files. Adding this to our applications was much easier than constantly reminding developers to turn off sourcemaps in their developer tools.

Using npm:

npm install skip-map --save

Skip Map middleware must be called before any static middleware.

var express = require('express'),
    skipMap = require('skip-map'),
    app = express();

app.use(skipMap());

app.use(express.static('./public'));

app.listen(3000, function() {
    console.log('Server is listening on port 3000');
});

Returns the skip map middleware function for Express. Takes an optional callback to define how requests for .map files should be handled. When a callback function is not provided, it will just end the request by calling res.send('').

Example:

// Without a callback function
app.use(skipMap());

// With a callback function
app.use(skipMap(function(req, res, next) {
    console.log('Skipping request for a .map file');
    res.send('');
}));

// Skip only in Development
app.use(skipMap(function(req, res, next) {
    if(process.env.NODE_ENV === 'development') {
        console.log('Skipping request for a .map file');
        res.send('');
    } else {
        next(); // will try to load the .map file if exists
    }
}));

Found a bug? Have an enhancement? Create a new issue. I will try to get it fixed as soon as possible.

Want to contribute to the project? Fork and submit a pull request.

Licensed under the MIT license. See LICENSE in the repository for more information.