From f63b8bb79d7cc9060319037e5e641ffe123997b0 Mon Sep 17 00:00:00 2001
From: Bianca Nenciu <nbianca@users.noreply.github.com>
Date: Thu, 6 Jun 2019 12:30:52 +0300
Subject: [PATCH] FIX: Periodically ensure consistency of categories. (#7663)

---
 app/jobs/scheduled/ensure_db_consistency.rb |  1 +
 app/models/category.rb                      |  9 +++++++++
 lib/tasks/import.rake                       |  2 +-
 spec/models/category_spec.rb                | 18 ++++++++++++++++++
 4 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/app/jobs/scheduled/ensure_db_consistency.rb b/app/jobs/scheduled/ensure_db_consistency.rb
index de9f4e8cb67..dd85fa0b537 100644
--- a/app/jobs/scheduled/ensure_db_consistency.rb
+++ b/app/jobs/scheduled/ensure_db_consistency.rb
@@ -21,6 +21,7 @@ module Jobs
       CategoryTagStat.ensure_consistency!
       User.ensure_consistency!
       UserAvatar.ensure_consistency!
+      Category.ensure_consistency!
     end
   end
 end
diff --git a/app/models/category.rb b/app/models/category.rb
index 096ed96aba3..6dc5530e2b4 100644
--- a/app/models/category.rb
+++ b/app/models/category.rb
@@ -664,6 +664,15 @@ class Category < ActiveRecord::Base
     end
   end
 
+  def self.ensure_consistency!
+    Category
+      .joins('LEFT JOIN topics ON categories.topic_id = topics.id AND topics.deleted_at IS NULL')
+      .where({ topics: { id: nil }})
+      .find_each do |category|
+      category.create_category_definition
+    end
+  end
+
   private
 
   def check_permissions_compatibility(parent_permissions, child_permissions)
diff --git a/lib/tasks/import.rake b/lib/tasks/import.rake
index e54ed4260df..92c4b90a558 100644
--- a/lib/tasks/import.rake
+++ b/lib/tasks/import.rake
@@ -428,7 +428,7 @@ end
 
 def create_category_definitions
   log "Creating category definitions"
-  Category.where(topic_id: nil).each(&:create_category_definition)
+  Category.ensure_consistency!
 end
 
 def log(message)
diff --git a/spec/models/category_spec.rb b/spec/models/category_spec.rb
index 39bce54d188..5746d396311 100644
--- a/spec/models/category_spec.rb
+++ b/spec/models/category_spec.rb
@@ -890,4 +890,22 @@ describe Category do
     end
   end
 
+  describe "#ensure_consistency!" do
+    it "creates category topic" do
+      category = Fabricate(:category)
+      category_destroyed = Fabricate(:category)
+      category_trashed = Fabricate(:category)
+
+      category_topic_id = category.topic.id
+      category_destroyed.topic.destroy!
+      category_trashed.topic.trash!
+
+      Category.ensure_consistency!
+
+      expect(category.reload.topic_id).to eq(category_topic_id)
+      expect(category_destroyed.reload.topic).to_not eq(nil)
+      expect(category_trashed.reload.topic).to_not eq(nil)
+    end
+  end
+
 end