Pre-calculate Emoji digests

app/controllers/projects_controller.rb

@@ -138,7 +138,7 @@ class ProjectsController < Projects::ApplicationController
     participants = ::Projects::ParticipantsService.new(@project, current_user).execute(note_type, note_id)
 
     @suggestions = {
-      emojis: autocomplete_emojis,
+      emojis: AwardEmoji.urls,
       issues: autocomplete.issues,
       mergerequests: autocomplete.merge_requests,
       members: participants
@@ -235,17 +235,6 @@ class ProjectsController < Projects::ApplicationController
     )
   end
 
-  def autocomplete_emojis
-    Rails.cache.fetch("autocomplete-emoji-#{Gemojione::VERSION}") do
-      Emoji.emojis.map do |name, emoji|
-        {
-          name: name,
-          path: view_context.image_url("#{emoji["unicode"]}.png")
-        }
-      end
-    end
-  end
-
   def repo_exists?
     project.repository_exists? && !project.empty_repo?
   end

lib/award_emoji.rb

@@ -48,4 +48,23 @@ class AwardEmoji
       JSON.parse(File.read(json_path))
     end
   end
+
+  # Returns an Array of Emoji names and their asset URLs.
+  def self.urls
+    @urls ||= begin
+      path = File.join(Rails.root, 'fixtures', 'emojis', 'digests.json')
+      prefix = Gitlab::Application.config.assets.prefix
+      digest = Gitlab::Application.config.assets.digest
+
+      JSON.parse(File.read(path)).map do |hash|
+        if digest
+          fname = "#{hash['unicode']}-#{hash['digest']}"
+        else
+          fname = hash['unicode']
+        end
+
+        { name: hash['name'], path: "#{prefix}/#{fname}.png" }
+      end
+    end
+  end
 end

lib/tasks/gemojione.rake

-# This task will generate a standard and Retina sprite of all of the current
-# Gemojione Emojis, with the accompanying SCSS map.
-#
-# It will not appear in `rake -T` output, and the dependent gems are not
-# included in the Gemfile by default, because this task will only be needed
-# occasionally, such as when new Emojis are added to Gemojione.
-
-begin
+namespace :gemojione do
+  desc 'Generates Emoji SHA256 digests'
+  task digests: :environment do
+    require 'digest/sha2'
+    require 'json'
+
+    dir = Gemojione.index.images_path
+
+    digests = AwardEmoji.emojis.map do |name, emoji_hash|
+      fpath = File.join(dir, "#{emoji_hash['unicode']}.png")
+      digest = Digest::SHA256.file(fpath).hexdigest
+
+      { name: name, unicode: emoji_hash['unicode'], digest: digest }
+    end
+
+    out = File.join(Rails.root, 'fixtures', 'emojis', 'digests.json')
+
+    File.open(out, 'w') do |handle|
+      handle.write(JSON.pretty_generate(digests))
+    end
+  end
+
+  # This task will generate a standard and Retina sprite of all of the current
+  # Gemojione Emojis, with the accompanying SCSS map.
+  #
+  # It will not appear in `rake -T` output, and the dependent gems are not
+  # included in the Gemfile by default, because this task will only be needed
+  # occasionally, such as when new Emojis are added to Gemojione.
+  task sprite: :environment do
+    begin
       require 'sprite_factory'
       require 'rmagick'
-rescue LoadError
+    rescue LoadError
       # noop
-end
+    end
 
-namespace :gemojione do
-  task sprite: :environment do
     check_requirements!
 
     SIZE   = 20

spec/lib/award_emoji_spec.rb

+require 'spec_helper'
+
+describe AwardEmoji do
+  describe '.urls' do
+    subject { AwardEmoji.urls }
+
+    it { is_expected.to be_an_instance_of(Array) }
+    it { is_expected.to_not be_empty }
+
+    context 'every Hash in the Array' do
+      it 'has the correct keys and values' do
+        subject.each do |hash|
+          expect(hash[:name]).to be_an_instance_of(String)
+          expect(hash[:path]).to be_an_instance_of(String)
+        end
+      end
+    end
+  end
+end