Universal JavaScript applications are tough to setup. Either you buy into a framework like Next.js or react-server, fork a boilerplate, or set things up yourself. Razzle aims to fill this void by abstracting all the required tooling for your universal JavaScript application into a single dependency, and then leaving the rest of the architectural decisions about frameworks, routing, and data fetching up to you.
Razzle comes with the "battery-pack included":
- 🔥 Universal Hot Module Replacement, so both the client and server update whenever you make edits. No annoying restarts necessary
- Comes with your favorite ES6 JavaScript goodies (through
babel-preset-razzle) - Comes with the same CSS setup as create-react-app
- Works with React, Preact, Elm, Reason-React, Inferno, and Rax as well as Angular and Vue if that's your thing
- Escape hatches for customization via
.babelrcandrazzle.config.js - Jest test runner setup with sensible defaults via
razzle test
npm install -g create-razzle-app
create-razzle-app my-app
cd my-app
npm startThen open http://localhost:3000/ to see your app. Your console should look like this:
That's it. You don't need to worry about setting up multiple webpack configs or other build tools. Just start editing src/App.js and go!
Below is a list of commands you will probably find useful.
Runs the project in development mode.
You can view your application at http://localhost:3000
The page will reload if you make edits.
Builds the app for production to the build folder.
The build is minified and the filenames include the hashes. Your app is ready to be deployed!
Runs the compiled app in production.
You can again view your application at http://localhost:3000
Runs the test watcher (Jest) in an interactive mode. By default, runs tests related to files changed since the last commit.
To debug the node server, you can use razzle start --inspect. This will start the node server and enable the inspector agent. For more information, see this.
Table of Contents
Razzle comes with most of ES6 stuff you need. However, if you want to add your own babel transformations, just add a .babelrc file to the root of your project.
{
"presets": [
"razzle/babel",
"stage-0"
]
}You can also extend the underlying webpack config. Create a file called razzle.config.js in your project's root.
// razzle.config.js
module.exports = {
modify: (config, {target, dev}, webpack) => {
// do something to config
return config
}
}A word of advice: razzle.config.js is an escape hatch. However, since it's just JavaScript, you can and should publish your modify function to npm to make it reusable across your projects. For example, imagine you added some custom webpack loaders and published it as a package to npm as my-razzle-modifictions. You could then write your razzle.config.js like so:
// razzle.config.js
const modify = require('my-razzle-modifictions');
module.exports = {
modify
}
Last but not least, if you find yourself needing a more customized setup, Razzle is very forkable. There is one webpack configuration factory that is 300 lines of code, and 4 scripts (build, start, test, and init). The paths setup is shamelessly taken from create-react-app, and the rest of the code related to logging.
The environment variables are embedded during the build time. Since Razzle produces a static HTML/CSS/JS bundle and an equivalent static bundle for your server, it cannot possibly read them at runtime.
process.env.RAZZLE_PUBLIC_DIR: Path to the public directory.process.env.RAZZLE_ASSETS_MANIFEST: Path to a file containing compiled asset outputsprocess.env.REACT_DEV_BUNDLE_PATH: Relative path to where React will be bundled during development. Unless you are modifying the output path of your webpack config, you can safely ignore this. This path is used byreact-error-overlayand webpack to power up the fancy runtime error iframe. For example, if you are using common chunks and an extra entry to create a vendor bundle with stuff like react, react-dom, react-router, etc. calledvendor.js, and you've changed webpack's output to[name].jsin development, you'd want to set this environment variable to/static/js/vendor.js. If you do not make this change, nothing bad will happen, you will simply not get the cool error overlay when there are runtime errors. You'll just see them in the console. Note: This does not impact production bundling.process.env.VERBOSE: default is false, setting this to true will not clear the console when you make edits in development (useful for debugging).process.env.PORT: default is3000, unless changedprocess.env.HOST: default is0.0.0.0process.env.NODE_ENV:'development'or'production'process.env.BUILD_TARGET: either'client'or'server'
You can create your own custom build-time environment variables. They must start
with RAZZLE_. Any other variables except the ones listed above will be ignored to avoid accidentally exposing a private key on the machine that could have the same name. Changing any environment variables will require you to restart the development server if it is running.
These environment variables will be defined for you on process.env. For example, having an environment variable named RAZZLE_SECRET_CODE will be exposed in your JS as process.env.RAZZLE_SECRET_CODE.
Defining environment variables can vary between OSes. It’s also important to know that this manner is temporary for the life of the shell session.
set RAZZLE_SECRET_CODE=abcdef&&npm start(Note: the lack of whitespace is intentional.)
RAZZLE_SECRET_CODE=abcdef npm startTo define permanent environment variables, create a file called .env in the root of your project:
RAZZLE_SECRET_CODE=abcdef
.env: Default..env.local: Local overrides. This file is loaded for all environments except test..env.development,.env.test,.env.production: Environment-specific settings..env.development.local,.env.test.local,.env.production.local: Local overrides of environment-specific settings.
Files on the left have more priority than files on the right:
npm start:.env.development.local,.env.development,.env.local,.envnpm run build:.env.production.local,.env.production,.env.local,.envnpm test:.env.test.local,.env.test,.env(note.env.localis missing)
These variables will act as the defaults if the machine does not explicitly set them.
Please refer to the dotenv documentation for more details.
Note: If you are defining environment variables for development, your CI and/or hosting platform will most likely need these defined as well. Consult their documentation how to do this. For example, see the documentation for Travis CI or Heroku.
tl;dr: 2 configs, 2 ports, 2 webpack instances, both watching and hot reloading the same filesystem, in parallel during development and a little webpack.output.publicPath magic.
In development mode (razzle start), Razzle bundles both your client and server code using two different webpack instances running with Hot Module Replacement in parallel. While your server is bundled and run on whatever port your specify in src/index.js (3000 is the default), the client bundle (i.e. entry point at src/client.js) is served via webpack-dev-server on a different port (3001 by default) with its publicPath explicitly set to localhost:3001 (and not / like many other setups do). Then the server's html template just points to the absolute url of the client JS: localhost:3001/static/js/client.js. Since both webpack instances watch the same files, whenever you make edits, they hot reload at exactly the same time. Best of all, because they use the same code, the same webpack loaders, and the same babel transformations, you never run into a React checksum mismatch error.
MIT License
Thanks goes to these wonderful people (emoji key):
 Jared Palmer 💬 💻 🎨 📖 💡 🤔 👀 |
 Jari Zwarts 💬 💻 🤔 🔌 👀 |
 Dan Abramov 💻 🤔 |
 Eric Clemmons 💻 🤔 |
|---|
This project follows the all-contributors specification. Contributions of any kind welcome!