Action Cable's JavaScript library can optionally be imported as an ES6 module via `import { … } from "@rails/actioncable/src"`, but that module is broken in most of the releases published on npm:
```
ERROR in ./node_modules/@rails/actioncable/src/connection.js
Module not found: Error: Can't resolve './internal' in './node_modules/@rails/actioncable/src'
@ ./node_modules/@rails/actioncable/src/connection.js
@ ./node_modules/@rails/actioncable/src/index.js
```
Because `internal.js` was gitignored, it would only be included if the publisher happened to have it generated locally. Committing it to version control ensures that won't happen, and gives us better visibility into changes over time.
References:
- https://github.com/rails/rails/pull/34370
- c0368ad090
* Rename .coffee files in ActionCable test suite in prep for decaffeination
* Decaffeinate ActionCable tests
* Replace Blade with Karma and Rollup to run ActionCable JS tests
- Add karma and qunit devDependencies
- Add test script to ActionCable package
- Use rollup to bundle ActionCable tests
- Use karma as the ActionCable JS test runner
* Replace vendored mock-socket with package devDependency in ActionCable
* Move ActionCable yarn install to TravisCI before_install config
* Clean up decaffeinated ActionCable tests to use consistent formatting
We've replaced the sprockets `//= require` directives with ES2015
imports. As a result, the ActionCable javascript can now be compiled
with rollup (like ActiveStorage already is).
- Rename action_cable/index.js.erb -> action_cable/index.js
- Add rake task to generate a javascript module of the ActionCable::INTERNAL ruby hash
This will allow us to get rid of ERB from the actioncable javascript,
since it is only used to interpolate ActionCable::INTERNAL.to_json.
- Import INTERNAL directly in ActionCable Connection module
This is necessary to remove a load-order dependency conflict in the
rollup-compiled build. Using ActionCable.INTERNAL would result in a
runtime error:
```
TypeError: Cannot read property 'INTERNAL' of undefined
```
because ActionCable.INTERNAL is not set before the Connection module
is executed.
All other ActionCable.* references are executed inside of the body of a
function, so there is no load-order dependency there.
- Add eslint and eslint-plugin-import devDependencies to actioncable
These will be used to add a linting setup to actioncable like the one
in activestorage.
- Add .eslintrc to actioncable
This lint configuration was copied from activestorage
- Add lint script to actioncable
This is the same as the lint script in activestorage
- Add babel-core, babel-plugin-external-helpers, and babel-preset-env devDependencies to actioncable
These will be used to add ES2015 transpilation support to actioncable
like we have in activestorage.
- Add .babelrc to actioncable
This configuration was copied from activestorage
- Enable loose mode in ActionCable's babel config
This generates a smaller bundle when compiled
- Add rollup devDependencies to actioncable
These will be used to add a modern build pipeline to actioncable like
the one in activestorage.
- Add rollup config to actioncable
This is essentially the same as the rollup config from activestorage
- Add prebuild and build scripts to actioncable package
These scripts were copied from activestorage
- Invoke code generation task as part of actioncable's prebuild script
This will guarantee that the action_cable/internal.js module is
available at build time (which is important, because two other modules
now depend on it).
- Update actioncable package to reference the rollup-compiled files
Now that we have a fully functional rollup pipeline in actioncable, we
can use the compiled output in our npm package.
- Remove build section from ActionCable blade config
Now that rollup is responsible for building ActionCable, we can remove
that responsibility from Blade.
- Remove assets:compile and assets:verify tasks from ActionCable
Now that we've added a compiled ActionCable bundle to version control,
we don't need to compile and verify it at publish-time.
(We're following the pattern set in ActiveStorage.)
- Include compiled ActionCable javascript bundle in published gem
This is necessary to maintain support for depending on the ActionCable
javascript through the Sprockets asset pipeline.
- Add compiled ActionCable bundle to version control
This mirrors what we do in ActiveStorage, and allows ActionCable to
continue to be consumed via the sprockets-based asset pipeline when
using a git source instead of a published version of the gem.
