(dev/drupal#8) Migrate bower.json into composer.json via composer-downloads-plugin

[totten]

Before

• JS and CSS libraries are downloaded via bower.
• bower is deprecated.
• bower is slow.
• bower requires installing NodeJS.
• bower requires installing Bower.

After

• composer install downloads the bower_components folder.
• composer has a better cache.
• composer is fast.
• You can setup a dev build with fewer dependencies.
• All of the bower_components will land in the same canonical location, regardless of project structure and environment.

Comments

This commit is flagged work-in-progress because it depends on an unreleased branch of a composer plugin. I just want to push it up for the moment so some people can see it. I've opened an issue LastCallMedia/ComposerExtraFiles#2 to discuss the path to publication.

This depends on civicrm/composer-downloads-plugin, which is an updated variant of lastcall/composer-extra-files. It has a few key characteristics:

• It does not require any root-level package configuration or third-party tools/runtimes.
• It produces a file-structure that closely matches the current one.
• It produces the same file-structure whether one (a) uses civicrm-core as root-package or (b) uses civicrm-core as a dependency inside a bigger project.
• It is fairly transparent and tweakable - anyone who wants to submit a PR to add/upgrade/remove JS/CSS dependencies should be able to do so.
• When we roll out civicrm extension/composer bridge, extensions should be able to use it while being compatible with several different deployment scenarios.

Technical Details

To try this out, I renamed my old bower_components, ran composer, and compared the new/old trees. The substance all looks good -- there are no missing or differing files. However, there is some new detritus. (Edit: This has been resolved by adding support for ignore directives. The subsequent discussion has been revised to match.)

$ mv bower_components{,.orig}
$ composer install
...
$ colordiff -ru bower_components{.orig,} -x .bower.json -x .composer-downloads -x .setupsh.ts

Only in bower_components.orig/checklist-model: test
Only in bower_components.orig/dc-2.1.x: bower.json
Only in bower_components.orig/font-awesome: bower.json
Only in bower_components.orig/jstree: bower.json

These appear to be trivial differences:

• For checklist-model/test, the old tree simply has an empty folder. There's no real content in either old or new tree.
• For the bower.json files, the new tree is more consistent with the ignore specification. The difference arises because (in the old tree) bower doesn't let you ignore bower.json. But we don't really need the file at runtime.

See also: https://lab.civicrm.org/dev/drupal/issues/8

[civibot]

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[totten]

I've pushed an update which imports a bunch of the ignore clauses from bower -- the updated description how shows only a couple trivial differences between the old+new trees.

Additionally, to improve readability, I consolidated all the path statements into default path formula.

[colemanw]

@totten I have rebased the latest upstream commits with my select2 repo and tagged it v3.5-civicrm-1.0 per your suggestion.

[totten]

Cheers @colemanw. I've pushed an update to use the new tag.