Fix #4129: Remove tag alias caching.

app/logical/tag_alias_correction.rb

@@ -13,19 +13,12 @@ class TagAliasCorrection
 
   def statistics_hash
     @statistics_hash ||= {
-      "antecedent_cache" => Cache.get("ta:" + Cache.hash(tag_alias.antecedent_name)),
-      "consequent_cache" => Cache.get("ta:" + Cache.hash(tag_alias.consequent_name)),
       "antecedent_count" => Tag.find_by_name(tag_alias.antecedent_name).try(:post_count),
       "consequent_count" => Tag.find_by_name(tag_alias.consequent_name).try(:post_count)
     }
   end
 
-  def clear_cache
-    tag_alias.clear_all_cache
-  end
-
   def fix!
-    clear_cache
     tag_alias.delay(:queue => "default").update_posts
   end
 end

app/models/tag_alias.rb

@@ -1,28 +1,10 @@
 class TagAlias < TagRelationship
-  after_save :clear_all_cache
-  after_destroy :clear_all_cache
-  after_save :clear_all_cache, if: ->(rec) {rec.is_retired?}
   after_save :create_mod_action
   validates_uniqueness_of :antecedent_name, scope: :status, conditions: -> { active }
   validate :absence_of_transitive_relation
   validate :wiki_pages_present, on: :create, unless: :skip_secondary_validations
   validate :mininum_antecedent_count, on: :create, unless: :skip_secondary_validations
 
-  module CacheMethods
-    extend ActiveSupport::Concern
-
-    module ClassMethods
-      def clear_cache_for(name)
-        Cache.delete("ta:#{Cache.hash(name)}")
-      end
-    end
-
-    def clear_all_cache
-      TagAlias.clear_cache_for(antecedent_name)
-      TagAlias.clear_cache_for(consequent_name)
-    end
-  end
-
   module ApprovalMethods
     def approve!(update_topic: true, approver: CurrentUser.user)
       CurrentUser.scoped(approver) do
@@ -50,7 +32,6 @@ class TagAlias < TagRelationship
     end
   end
 
-  include CacheMethods
   include ApprovalMethods
   include ForumMethods
 
@@ -63,9 +44,9 @@ class TagAlias < TagRelationship
   end
 
   def self.to_aliased(names)
-    Cache.get_multi(Array(names), "ta") do |tag|
-      ActiveRecord::Base.select_value_sql("select consequent_name from tag_aliases where status in ('active', 'processing') and antecedent_name = ?", tag) || tag.to_s
-    end.values
+    names = Array(names)
+    aliases = active.where(antecedent_name: names).map { |ta| [ta.antecedent_name, ta.consequent_name] }.to_h
+    names.map { |name| aliases[name] || name }
   end
 
   def process!(update_topic: true)
@@ -80,7 +61,6 @@ class TagAlias < TagRelationship
         update(status: "processing")
         move_aliases_and_implications
         move_saved_searches
-        clear_all_cache
         ensure_category_consistency
         update_posts
         forum_updater.update(approval_message(approver), "APPROVED") if update_topic
@@ -197,7 +177,6 @@ class TagAlias < TagRelationship
 
   def reject!(update_topic: true)
     update(status: "deleted")
-    clear_all_cache
     forum_updater.update(reject_message(CurrentUser.user), "REJECTED") if update_topic
   end
 

test/unit/tag_alias_correction_test.rb

@@ -16,17 +16,13 @@ class TagAliasCorrectionTest < ActiveSupport::TestCase
       CurrentUser.ip_addr = nil
     end
 
-    context "with a bad cache and post counts" do
+    context "with a bad post count" do
       setup do
-        Cache.delete("ta:#{Cache.hash('bbb')}")
-        Cache.put("ta:#{Cache.hash('aaa')}", "zzz")
         Tag.where(:name => "aaa").update_all("post_count = -3")
         @correction = TagAliasCorrection.new(@tag_alias.id)
       end
 
       should "have the correct statistics hash" do
-        assert_equal("zzz", @correction.statistics_hash["antecedent_cache"])
-        assert_nil(@correction.statistics_hash["consequent_cache"])
         assert_equal(-3, @correction.statistics_hash["antecedent_count"])
         assert_equal(1, @correction.statistics_hash["consequent_count"])
       end
@@ -44,11 +40,6 @@ class TagAliasCorrectionTest < ActiveSupport::TestCase
       context "that is fixed" do
         setup do
           @correction.fix!
-          TagAlias.to_aliased(["aaa"])
-        end
-
-        should "now have the correct cache" do
-          assert_equal("bbb", Cache.get("ta:#{Cache.hash('aaa')}"))
         end
 
         should "now have the correct count" do

test/unit/tag_alias_test.rb

@@ -106,22 +106,14 @@ class TagAliasTest < ActiveSupport::TestCase
     end
 
     should "convert a tag to its normalized version" do
-      tag1 = FactoryBot.create(:tag, :name => "aaa")
-      tag2 = FactoryBot.create(:tag, :name => "bbb")
-      ta = FactoryBot.create(:tag_alias, :antecedent_name => "aaa", :consequent_name => "bbb")
-      normalized_tags = TagAlias.to_aliased(["aaa", "ccc"])
-      assert_equal(["bbb", "ccc"], normalized_tags.sort)
-    end
+      tag1 = create(:tag, name: "aaa")
+      tag2 = create(:tag, name: "bbb")
+      ta = create(:tag_alias, antecedent_name: "aaa", consequent_name: "bbb")
 
-    should "update the cache" do
-      tag1 = FactoryBot.create(:tag, :name => "aaa")
-      tag2 = FactoryBot.create(:tag, :name => "bbb")
-      ta = FactoryBot.create(:tag_alias, :antecedent_name => "aaa", :consequent_name => "bbb")
-      assert_nil(Cache.get("ta:#{Cache.hash("aaa")}"))
-      TagAlias.to_aliased(["aaa"])
-      assert_equal("bbb", Cache.get("ta:#{Cache.hash("aaa")}"))
-      ta.destroy
-      assert_nil(Cache.get("ta:#{Cache.hash("aaa")}"))
+      assert_equal(["bbb"], TagAlias.to_aliased("aaa"))
+      assert_equal(["bbb", "ccc"], TagAlias.to_aliased(["aaa", "ccc"]))
+      assert_equal(["ccc", "bbb"], TagAlias.to_aliased(["ccc", "bbb"]))
+      assert_equal(["bbb", "bbb"], TagAlias.to_aliased(["aaa", "aaa"]))
     end
 
     context "saved searches" do