AO3-7135 Record canonized/decanonized dates on tags

app/models/search/tag_indexer.rb

@@ -23,6 +23,8 @@ def self.mapping
         },
         tag_type: { type: "keyword" },
         sortable_name: { type: "keyword" },
+        canonized_at: { type: "date" },
+        decanonized_at: { type: "date" },
         uses: { type: "integer" },
         unwrangled: { type: "boolean" }
       }
@@ -72,7 +74,7 @@ def document(object)
       root: false,
       only: [
         :id, :name, :sortable_name, :merger_id, :canonical, :created_at,
-        :unwrangleable
+        :canonized_at, :decanonized_at, :unwrangleable
       ]
     ).merge(
       has_posted_works: object.has_posted_works?,

app/models/search/tag_query.rb

@@ -52,15 +52,19 @@ def sort
     when "created_at"
       column = "created_at"
       direction ||= "desc"
+    when "canonized_at"
+      column = "canonized_at"
+      direction ||= "desc"
+    when "decanonized_at"
+      column = "decanonized_at"
+      direction ||= "desc"
     else
       column = "name.keyword"
       direction ||= "asc"
     end
     sort_hash = { column => { order: direction } }
 
-    if column == "created_at"
-      sort_hash[column][:unmapped_type] = "date"
-    end
+    sort_hash[column][:unmapped_type] = "date" if %w[created_at canonized_at decanonized_at].include?(column)
 
     sort_by_id = { id: { order: direction } }
 

app/models/search/tag_search_form.rb

@@ -68,11 +68,13 @@ def sort_options
     [
       %w[Name name],
       ["Date Created", "created_at"],
+      ["Date Canonized", "canonized_at"],
+      ["Date Decanonized", "decanonized_at"],
       %w[Uses uses]
     ]
   end
 
   def default_sort_direction
-    %w[created_at uses].include?(sort_column) ? "desc" : "asc"
+    %w[created_at canonized_at decanonized_at uses].include?(sort_column) ? "desc" : "asc"
   end
 end

app/models/tag.rb

@@ -255,6 +255,15 @@ def update_wrangler(tag)
     end
   end
 
+  before_save :set_canonization_date, if: :will_save_change_to_canonical?
+  def set_canonization_date
+    if canonical?
+      self.canonized_at = Time.current
+    else
+      self.decanonized_at = Time.current
+    end
+  end
+
   after_save :check_type_changes, if: :saved_change_to_type?
   def check_type_changes
     return if type_before_last_save.nil?

app/views/tags/edit.html.erb

@@ -13,6 +13,16 @@
 
 <% if logged_in_as_admin? %>
   <p class="notes"><%= ts("Last updated by %{wrangler} on %{date}", wrangler: @tag.last_wrangler.try(:login) || '---', date: @tag.updated_at) %></p>
+  <% if @tag.canonized_at || @tag.decanonized_at %>
+    <p class="notes">
+      <% if @tag.canonized_at %>
+        <%= t(".last_canonized", date: @tag.canonized_at.utc.strftime("%Y-%m-%d %H:%M:%S")) %>
+      <% end %>
+      <% if @tag.decanonized_at %>
+        <%= t(".last_decanonized", date: @tag.decanonized_at.utc.strftime("%Y-%m-%d %H:%M:%S")) %>
+      <% end %>
+    </p>
+  <% end %>
 <% end %>
 
 <%= form_for @tag, as: :tag, url: { action: "update", id: @tag}, html: { method: :put } do |f| %>

config/locales/views/en.yml

@@ -3078,6 +3078,8 @@ en:
       wrangling_tools: Wrangling Tools
   tags:
     edit:
+      last_canonized: Last canonized on %{date} UTC.
+      last_decanonized: Last decanonized on %{date} UTC.
       save_changes: Save changes
       submit_legend: Submit
     index:

db/migrate/20260725153049_add_canonization_dates_to_tags.rb

@@ -0,0 +1,10 @@
+class AddCanonizationDatesToTags < ActiveRecord::Migration[8.1]
+  uses_departure! if Rails.env.staging? || Rails.env.production?
+
+  def change
+    change_table :tags, bulk: true do |t|
+      t.datetime :canonized_at, default: nil, null: true
+      t.datetime :decanonized_at, default: nil, null: true
+    end
+  end
+end

features/tags_and_wrangling/tag_wrangling_admin.feature

@@ -32,6 +32,36 @@ Feature: Tag wrangling
     Then I should not see "Amelie"
       And I should see "Amélie"
 
+  Scenario: Admin can see when a tag was last canonized and decanonized
+
+  Given I am logged in as a "tag_wrangling" admin
+    And a fandom exists with name: "Amelie", canonical: false
+  When I edit the tag "Amelie"
+  Then I should not see "Last canonized on"
+    And I should not see "Last decanonized on"
+  When I check "Canonical"
+    And I press "Save changes"
+    And I edit the tag "Amelie"
+  Then I should see "Last canonized on"
+    And I should not see "Last decanonized on"
+  When I uncheck "Canonical"
+    And I press "Save changes"
+    And I edit the tag "Amelie"
+  Then I should see "Last canonized on"
+    And I should see "Last decanonized on"
+
+  Scenario: Tag wrangler cannot see when a tag was last canonized or decanonized
+
+  Given I am logged in as a "tag_wrangling" admin
+    And a fandom exists with name: "Amelie", canonical: true
+  When I edit the tag "Amelie"
+    And I uncheck "Canonical"
+    And I press "Save changes"
+    And I am logged in as a tag wrangler
+    And I edit the tag "Amelie"
+  Then I should not see "Last canonized on"
+    And I should not see "Last decanonized on"
+
   Scenario: Admin can rename a tag using Eastern characters
 
   Given I am logged in as a "tag_wrangling" admin

spec/models/search/tag_query_spec.rb

@@ -197,6 +197,16 @@
       expect(q.generated_query[:sort]).to eq([{ "created_at" => { order: "asc", unmapped_type: "date" } }, { id: { order: "asc" } }])
     end
 
+    it "allows you to sort by Date Canonized" do
+      q = TagQuery.new(sort_column: "canonized_at")
+      expect(q.generated_query[:sort]).to eq([{ "canonized_at" => { order: "desc", unmapped_type: "date" } }, { id: { order: "desc" } }])
+    end
+
+    it "allows you to sort by Date Decanonized" do
+      q = TagQuery.new(sort_column: "decanonized_at")
+      expect(q.generated_query[:sort]).to eq([{ "decanonized_at" => { order: "desc", unmapped_type: "date" } }, { id: { order: "desc" } }])
+    end
+
     it "allows you to sort by Uses" do
       q = TagQuery.new(sort_column: "uses")
       expect(q.generated_query[:sort]).to eq([{ "uses" => { order: "desc" } }, { "name.keyword" => { order: "asc" } }, { id: { order: "desc" } }])

spec/models/tag_wrangling_spec.rb

@@ -18,6 +18,42 @@
         end.to(add_to_reindex_queue(work, :background) &
                not_add_to_reindex_queue(work, :main))
       end
+
+      it "sets canonized_at" do
+        freeze_time do
+          fandom.update!(canonical: true)
+          expect(fandom.canonized_at).to eq(Time.current)
+          expect(fandom.decanonized_at).to be_nil
+        end
+      end
+    end
+
+    context "when a tag is created as canonical" do
+      it "sets canonized_at" do
+        freeze_time do
+          fandom = create(:canonical_fandom)
+          expect(fandom.canonized_at).to eq(Time.current)
+          expect(fandom.decanonized_at).to be_nil
+        end
+      end
+    end
+
+    context "when a tag is created as non-canonical" do
+      it "does not set canonized_at or decanonized_at" do
+        fandom = create(:fandom)
+        expect(fandom.canonized_at).to be_nil
+        expect(fandom.decanonized_at).to be_nil
+      end
+    end
+
+    context "when canonical does not change" do
+      it "does not change canonized_at or decanonized_at" do
+        fandom = create(:canonical_fandom)
+        expect do
+          fandom.update!(unwrangleable: false)
+        end.to avoid_changing { fandom.reload.canonized_at } &
+               avoid_changing { fandom.reload.decanonized_at }
+      end
     end
 
     context "when canonical becomes false" do
@@ -37,6 +73,13 @@
                not_add_to_reindex_queue(work, :main))
       end
 
+      it "sets decanonized_at" do
+        freeze_time do
+          fandom.update!(canonical: false)
+          expect(fandom.decanonized_at).to eq(Time.current)
+        end
+      end
+
       it "removes favorite tags" do
         user = create(:user)
         user.favorite_tags.create(tag: fandom)