Using hot reloading while developing can improve your workflow. No more clicking through your application to a particular state each time you change the rendering code!
This example must be run standalone, instead of through the usual npm run examples
in this repository's root.
To install and run:
npm install
// for browserify
npm run hot-browserify
// for webpack
npm run hot-webpack
Edit package.json if you want to run on a different port.
If you're running inside a container or VM, add --host 0.0.0.0
(webpack) so you can access the dev server from your host machine.
Try clicking to increment the counter, then edit render.js! Your changes should instantly appear on the page without refreshing or upsetting the counter's value. Note that if you edit browser.js, your page will refresh and your state will be reset (only using webpack).
Running webpack-dev-server
with the --hot
argument enables hot module replacement, but to make use of it you need to add a little bit of code to your application.
When webpack detects a file has changed, module.hot.accept
gets a chance to 'claim' the reload and prevent the page from refreshing as it usually would.
We use that opportunity to replace the function the app uses to render.
We have to be careful to not reseat any references - so we pass a function that doesn't change to hg.app
(i.e. App.render
), but inside that function, we call a function which may change at runtime.
The main difference to webpack is that browserify does not come with a dev-server which is why we use http-server to host our example. Other than that it works quite similar. Under the hood browserify-hmr imitates webpack's hot module replacement.