docs/javascript/troubleshooting-when-using-shakapacker.md
# Client rendering crashes when configuring `optimization.runtimeChunk` to `multiple`
## Context
1. Ruby version: 3.1
2. Rails version: 7.0.6
3. Shakapacker version: 6.6.0
4. React on Rails version: 13.3.5
## The failure
Configuring Webpack to embed the runtime in each chunk and calling `react_component` twice in a rails view/partial causes the client render to crash with the following error:
```
Could not find component registered with name XXX. Registered component names include [ YYY ]. Maybe you forgot to register the component?
```
```
VM4859 clientStartup.js:132 Uncaught Error: ReactOnRails encountered an error while rendering component: XXX. See above error message.
at Object.get (ComponentRegistry.js:40:15)
at Object.getComponent (ReactOnRails.js:211:44)
at render (VM4859 clientStartup.js:103:53)
at forEachReactOnRailsComponentRender (VM4859 clientStartup.js:138:9)
at reactOnRailsPageLoaded (VM4859 clientStartup.js:164:5)
at renderInit (VM4859 clientStartup.js:205:9)
at onPageReady (VM4859 clientStartup.js:234:9)
at HTMLDocument.onReadyStateChange (VM4859 clientStartup.js:238:13)
```
## Configs
### Webpack configuration
```js
optimization: {
runtimeChunk: 'multiple'
},
```
### Rails view
```haml
= react_component("XXX", props: @props)
= yield
= react_component("YYY", props: @props)
```
## The problem
Configuring Webpack to embed the runtime in each chunk and calling `react_component` twice in a rails view/partial causes the client render to crash.
Read more at https://github.com/shakacode/react_on_rails/issues/1558.
## Solution
To overcome this issue, we could use [shakapacker](https://github.com/shakacode/shakapacker)'s default optimization configuration (pseudo-code):
```js
const { webpackConfig: baseClientWebpackConfig } = require('shakapacker');
// ...
config.optimization = baseClientWebpackConfig.optimization;
```
As it set the `optimization.runtimeChunk` to `single`. See its source:
`package/environments/base.js:115`
```js
optimization: {
splitChunks: { chunks: 'all' },
runtimeChunk: 'single'
},
```
https://github.com/shakacode/shakapacker/blob/cdf32835d3e0949952b8b4b53063807f714f9b24/package/environments/base.js#L115-L119
Or set `optimization.runtimeChunk` to `single` directly.