From 62987156128d4df25fcb9d89c200d646772884a6 Mon Sep 17 00:00:00 2001
From: rhymes <rhymes@hey.com>
Date: Tue, 1 Sep 2020 18:35:03 +0200
Subject: [PATCH] [deploy] Add unique index on articles slug user_id (#10126)

---
 app/models/article.rb                         | 33 +++++++++----------
 ...d_unique_index_to_articles_slug_user_id.rb | 15 +++++++++
 db/schema.rb                                  |  3 +-
 3 files changed, 33 insertions(+), 18 deletions(-)
 create mode 100644 db/migrate/20200901084210_add_unique_index_to_articles_slug_user_id.rb

diff --git a/app/models/article.rb b/app/models/article.rb
index df2c32f85..367bf7a88 100644
--- a/app/models/article.rb
+++ b/app/models/article.rb
@@ -49,30 +49,29 @@ class Article < ApplicationRecord
            inverse_of: :commentable,
            class_name: "Comment"
 
-  validates :slug, presence: { if: :published? }, format: /\A[0-9a-z\-_]*\z/,
-                   uniqueness: { scope: :user_id }
-  validates :title, presence: true,
-                    length: { maximum: 128 }
-  validates :user_id, presence: true
-  validates :feed_source_url, uniqueness: { allow_blank: true }
-  validates :canonical_url,
-            url: { allow_blank: true, no_local: true, schemes: %w[https http] },
-            uniqueness: { allow_blank: true }
   validates :body_markdown, length: { minimum: 0, allow_nil: false }, uniqueness: { scope: %i[user_id title] }
-  validate :validate_tag
-  validate :validate_video
-  validate :validate_collection_permission
-  validate :past_or_present_date
-  validate :canonical_url_must_not_have_spaces
-  validates :video_state, inclusion: { in: %w[PROGRESSING COMPLETED] }, allow_nil: true
   validates :cached_tag_list, length: { maximum: 126 }
+  validates :canonical_url, url: { allow_blank: true, no_local: true,
+                                   schemes: %w[https http] }, uniqueness: { allow_blank: true }
+  validates :feed_source_url, uniqueness: { allow_blank: true }
   validates :main_image, url: { allow_blank: true, schemes: %w[https http] }
   validates :main_image_background_hex_color, format: /\A#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})\z/
+  validates :slug, presence: { if: :published? }, format: /\A[0-9a-z\-_]*\z/
+  validates :slug, uniqueness: { scope: :user_id }
+  validates :title, presence: true, length: { maximum: 128 }
+  validates :user_id, presence: true
   validates :video, url: { allow_blank: true, schemes: %w[https http] }
-  validates :video_source_url, url: { allow_blank: true, schemes: ["https"] }
-  validates :video_thumbnail_url, url: { allow_blank: true, schemes: %w[https http] }
   validates :video_closed_caption_track_url, url: { allow_blank: true, schemes: ["https"] }
   validates :video_source_url, url: { allow_blank: true, schemes: ["https"] }
+  validates :video_source_url, url: { allow_blank: true, schemes: ["https"] }
+  validates :video_state, inclusion: { in: %w[PROGRESSING COMPLETED] }, allow_nil: true
+  validates :video_thumbnail_url, url: { allow_blank: true, schemes: %w[https http] }
+
+  validate :canonical_url_must_not_have_spaces
+  validate :past_or_present_date
+  validate :validate_collection_permission
+  validate :validate_tag
+  validate :validate_video
 
   before_validation :evaluate_markdown, :create_slug
   before_save :update_cached_user
diff --git a/db/migrate/20200901084210_add_unique_index_to_articles_slug_user_id.rb b/db/migrate/20200901084210_add_unique_index_to_articles_slug_user_id.rb
new file mode 100644
index 000000000..8d6f04aef
--- /dev/null
+++ b/db/migrate/20200901084210_add_unique_index_to_articles_slug_user_id.rb
@@ -0,0 +1,15 @@
+class AddUniqueIndexToArticlesSlugUserId < ActiveRecord::Migration[6.0]
+  disable_ddl_transaction!
+
+  def up
+    unless index_exists?(:articles, %i[slug user_id], unique: true)
+      add_index :articles, %i[slug user_id], unique: true, algorithm: :concurrently
+    end
+  end
+
+  def down
+    if index_exists?(:articles, %i[slug user_id], unique: true)
+      remove_index :articles, column: %i[slug user_id], algorithm: :concurrently
+    end
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index cf693a685..44e2304ec 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2020_08_28_045600) do
+ActiveRecord::Schema.define(version: 2020_09_01_084210) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "citext"
@@ -161,6 +161,7 @@ ActiveRecord::Schema.define(version: 2020_08_28_045600) do
     t.index ["public_reactions_count"], name: "index_articles_on_public_reactions_count", order: :desc
     t.index ["published"], name: "index_articles_on_published"
     t.index ["published_at"], name: "index_articles_on_published_at"
+    t.index ["slug", "user_id"], name: "index_articles_on_slug_and_user_id", unique: true
     t.index ["slug"], name: "index_articles_on_slug"
     t.index ["user_id"], name: "index_articles_on_user_id"
   end