Sep 29, 2015
React on Rails with webpack - React is not defined
I'm using the react on rails gem in a project I've been working on. It's great for using of React components in a Rails project and supports both server side and client side rendering.
If you've got webpack set up to work as part of your rails stack (example) the gem is a breeze to set up.
I did run into 1 problem recently though. I was getting an error when I deployed to heroku that I wasn't getting in dev mode.
Exception in rendering!
ReferenceError: React is not defined
To fix this, make sure you are exposing react in your webpack config file.
module.exports = {
...
module: {
loaders: [
// Make sure you have this line in your config!
{test: require.resolve('react'), loader: 'expose?React'},
...
]
}
};