Use of bazaarvoice_library_info_alter() to provide language specific BV loader files does not work

More info from another change record

Note that "dynamic" doesn't mean "runtime" (i.e. for every request) — that'd be terrible for performance. The dynamically added libraries are still cached, just like libraries defined in YML files. It's "dynamic" because you can use logic to add libraries.

A few ideas that come to mind

• Add a library for each configured locale, but then require the #attach to specify which locale library its attaching; not ideal
• Add JS that will append the BV loader
  to DOM using locale value provided hook_js_settings_alter()

Talked to team members to outline a path forward to append the BV loader JS as

• Add drupalSettings definition with items representing config within bazaarvoice.libraries.yml , e.g. core.libraries.yml
• Add new method (e.g. getBvDrupalSettings() to BazaarvoiceService to get configuration and prepare url fragments for drupalSettings
• Implement a hook_js_settings_alter() to update DrupalSettings values from BV config using BazaarvoiceService method, e.g. system_js_settings_alter()
• Refactor buildHostedJsPath() to use new method to get configuration and prepare path
• Ensure WriteReviewController::reviewContainer() works when using buildHostedJsPath()
• Add JS file to use prepared drupalSettings to append tag with async attribute
• Update bazaarvoice/hosted.external in bazaarvoice.libraries.yml to point to the JS file above; add dependency on bazaarvoice/drupalSettings
• Remove bazaarvoice_library_info_alter()

Next Steps

• Update issue summary with proposed solution and other sections

One remaining concern/question, how best to manage/store the parts of the JS loader resource path, and deliver it to the client via drupalSettings.

The BazaarvoiceService::buildHostedJsPath() with this patch in #2959188-11: Use v2 display API (bv.js instead of bvapi.js) returns the resource path as follows.

Hosted v1: has host and 4 pathname parts

$js_path = '//display.ugc.bazaarvoice.com/' . $mode . 'static/' . $client_name . '/' . $locale_code . '/bvapi.js';

Hosted v2: has host and 6 pathname parts

$js_path = '//apps.bazaarvoice.com/deployments/' . $client_name . '/' . $site_id . '/' . $mode . '/' . $locale_code . '/bv.js';

For client side logic to determine how to construct the JS resource path, how should drupalSettings be structured to inform client side logic how to construct the resource path?

After reviewing this, and recognizing how crazy this approach is, there is a different simpler way using hook_js_alter() to localize the loader file!

Alright, so with a far simpler approach, I've replaced the hook_library_info_alter() with hook_js_alter() implementation. Without a great a way to substitute the resource path within hook_js_alter(), I've updated the library definition path in order to be sure this logic only replaces this specific item.