When the web server you're using lies on a resource's file extension and content-type, saveWithCorrectExtension() FTW!
install
npm install --save save-with-correct-extension
usage
// require the module
var saveWithCorrectExtension = require('save-with-correct-extension');
saveWithCorrectExtension(urlToFetch, localPathWithoutExtension, callback);
// the callback with be called with (err) in case of error or (null, localPathWithExtension) if everything went wellCheck the example.js file for a practical example.