Webpack

Trying to document the usual problems people have with our webpack, and ways of fixing them.

Run it

compile the UI code + plugins:

bin/update - it all happens automatically during bin/update, but maybe that's not enough

rake update:ui - runs yarn in all the repositories, and then webpack

bin/webpack - (in ui-classic) runs just the webpack part

bin/webpack --watch - runs webpack and keeps watching for changes

Clear it

rake webpack:clobber - clear all webpack compiled code

rake yarn:clobber - clear installed npm packages from all repos - usually needed after Fedora upgrade

Plugins

Webpack doesn't just compile ui-classic code, it also compiles code from all rails plugins.

Specifically, rake webpack:paths generates a manageiq-ui-classic/config/webpack/paths.json containing paths to each gem with a package.json and app/javascript, and the output path to manageiq/public.

Webpack then reads that paths.json file to find all the sources and output path.

(You can use rake update:print_engines to see the list of relevant UI engines.)

Packs

Packs are just webpack entrypoints. In manageiq we have several packs:

• loaded as part of javascript_essential_dependencies:
  • runtime - just the webpack runtime
  • shims - various shims to support older browsers (may go away)
  • vendor - everything we use from node_modules, possibly other code shared betweeen multiple packs
• loaded as part of javascript_dependencies - after essential, before old JS
  • manageiq-ui-classic/globals.js - most external libraries we're using as globals
• loaded via javascript_common_packs
  • anything in ANY repo, named app/javascript/packs/*-common.js (ui-classic repo goes first, application-common goes first from ui-classic)
• loaded manually via javascript_pack_tag
  • anything under app/javascript/packs/ in any repo, without the -common.js suffix - never loaded automatically, always needs an explicit javascript_pack_tag in a haml

All the compiled packs end up in manageiq/public/packs/(repo_name)/(pack_name).(hash).js