Share asset_host from rails with webpack

[schovi]

Today I reach issue, where some of my assets was loaded from same domain as app and not from CDN as i have configured in environment/production.rb

(my solution)

if ENV['ASSETS_HOST'].present?
  config.action_controller.asset_host = ENV['ASSETS_HOST']
end

webpack scripts and styles was handled fine, because url is generated in rails, but all assets loaded inside .jsx? or .css did not have this domain obviously. It took me some time to find where is root cause of this and then solution was easy.

config/webpack/configuration.js

from

const publicPath = env.NODE_ENV !== 'production' && devServer.enabled ?
  `http://${devServer.host}:${devServer.port}/` : `/${paths.entry}/`

to

let publicPath
if (env.NODE_ENV !== 'production' && devServer.enabled) {
  publicPath = `http://${devServer.host}:${devServer.port}/`
} else {
  publicPath = `${env.ASSETS_HOST}/${paths.entry}/`
}

My opinion is, it should be shared across whole environment by default, because it can cause lot of confusion, but on other hand I can't find solution, which can be done without changing something directly in rails gem.

[gauravtiwari]

Fixed by #224