React-rails: Can't resolve react_ujs

[chrismv48]

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I followed the steps described in the readme to setup react via webpacker, but when I run ./bin/webpack-dev-server I got the following compile error:

ERROR in ./app/javascript/packs/server_rendering.js
Module not found: Error: Can't resolve 'react_ujs' in '/Users/chrisarmstrong/Projects/debate_platform/app/javascript/packs'
 @ ./app/javascript/packs/server_rendering.js 4:20-40
 @ multi (webpack)-dev-server/client?http://localhost:8080 ./app/javascript/packs/server_rendering.js

ERROR in ./app/javascript/packs/application.js
Module not found: Error: Can't resolve 'react_ujs' in '/Users/chrisarmstrong/Projects/debate_platform/app/javascript/packs'
 @ ./app/javascript/packs/application.js 13:20-40
 @ multi (webpack)-dev-server/client?http://localhost:8080 ./app/javascript/packs/application.js

Here are the contents of the two files in question:

packs/application.js
```console.log('Hello World from Webpacker')
// Support component names relative to this directory:
var componentRequireContext = require.context("components", true)
var ReactRailsUJS = require("react_ujs")
ReactRailsUJS.useContext(componentRequireContext)

`packs/server_rendering.js`
```var componentRequireContext = require.context("components", true)
var ReactRailsUJS = require("react_ujs")
ReactRailsUJS.useContext(componentRequireContext)

[rmosolgo]

The install generator _should_ do this for you, but can you try installing react_ujs with yarn?

yarn add react_ujs

?

Then, restart webpack-dev-server and try again?

[chrismv48]

@rmosolgo that worked, thanks! Not sure why the generator didn't work...

[asaletnik]

@chrismv48 - I had similar issue, check #716.

I guess we'll have to wait until @rmosolgo releases updated gem.
Until then gem 'react-rails', git: 'https://github.com/react/react-rails' should also help.