add Setting to defer js bundles

so if we have a bundle or bundles that fail due to DOM-ready race conditions exacerbated by Chrome 96, we can defer them without a deploy while we fix the code test plan: - Setting.set('deferred_js_bundles', 'foo,bar') will cause js_bundles `foo` and `bar` to be deferred - Setting.set('deferred_js_bundles', '*') will cause all js_bundles to be deferred - Setting.set('deferred_js_bundles', '*,!foo') will cause all js_bundles except for `foo` to be deferred refs FOO-2597 Change-Id: Ie976608a869e576c9eb2e2da0bf89b73cbe68b4a Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/281060 Tested-by: Service Cloud Jenkins <[email protected]> Reviewed-by: Charley Kline <[email protected]> Product-Review: Charley Kline <[email protected]> QA-Review: Charley Kline <[email protected]>
seandong · Dec 13, 2021 · 129f6c2 · 129f6c2
1 parent f01fdbb
commit 129f6c2
Showing 1 changed file with 7 additions and 0 deletions.
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
@@ -277,13 +277,20 @@ def include_js_bundles
       # execution is delayed until the DOM is ready.
       if new_js_bundles.present?
         concat javascript_tag new_js_bundles.map { |(bundle, plugin, defer)|
+                                defer ||= defer_js_bundle?(bundle)
                                 container = defer ? "window.deferredBundles" : "window.bundles"
                                 "(#{container} || (#{container} = [])).push('#{plugin ? "#{plugin}-" : ""}#{bundle}');"
                               }.join("\n")
       end
     end
   end
 
+  def defer_js_bundle?(bundle)
+    @deferred_js_bundles ||= Setting.get("deferred_js_bundles", "").split(",")
+    @deferred_js_bundles.include?(bundle.to_s) ||
+      (@deferred_js_bundles.include?("*") && @deferred_js_bundles.exclude?("!#{bundle}"))
+  end
+
   def include_css_bundles
     @rendered_css_bundles ||= []
     new_css_bundles = css_bundles - @rendered_css_bundles