Start tracking pool repositories

app/models/pool_repository.rb

+# frozen_string_literal: true
+
+class PoolRepository < ActiveRecord::Base
+  POOL_PREFIX = '@pools'
+
+  belongs_to :shard
+  validates :shard, presence: true
+
+  # For now, only pool repositories are tracked in the database. However, we may
+  # want to add other repository types in the future
+  self.table_name = 'repositories'
+
+  has_many :pool_member_projects, class_name: 'Project', foreign_key: :pool_repository_id
+
+  def shard_name
+    shard&.name
+  end
+
+  def shard_name=(name)
+    self.shard = Shard.by_name(name)
+  end
+end

app/models/project.rb

@@ -124,6 +124,7 @@ class Project < ActiveRecord::Base
   alias_attribute :title, :name
 
   # Relations
+  belongs_to :pool_repository
   belongs_to :creator, class_name: 'User'
   belongs_to :group, -> { where(type: 'Group') }, foreign_key: 'namespace_id'
   belongs_to :namespace

changelogs/unreleased/52300-pool-repositories.yml

+---
+title: Start tracking shards and pool repositories in the database
+merge_request: 22482
+author:
+type: other

config/initializers/fill_shards.rb

+return unless Shard.connected?
 return if Gitlab::Database.read_only?
 
 Shard.populate!

db/migrate/20181019032408_add_repositories_table.rb

+# frozen_string_literal: true
+
+class AddRepositoriesTable < ActiveRecord::Migration
+  DOWNTIME = false
+
+  def change
+    create_table :repositories, id: :bigserial do |t|
+      t.references :shard, null: false, index: true, foreign_key: { on_delete: :restrict }
+      t.string :disk_path, null: false, index: { unique: true }
+    end
+
+    add_column :projects, :pool_repository_id, :bigint
+    add_index :projects, :pool_repository_id, where: 'pool_repository_id IS NOT NULL'
+  end
+end

db/migrate/20181019105553_add_projects_pool_repository_id_foreign_key.rb

+# frozen_string_literal: true
+
+class AddProjectsPoolRepositoryIdForeignKey < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_foreign_key(
+      :projects,
+      :repositories,
+      column: :pool_repository_id,
+      on_delete: :nullify
+    )
+  end
+
+  def down
+    remove_foreign_key(:projects, column: :pool_repository_id)
+  end
+end

db/schema.rb

@@ -1703,6 +1703,7 @@ ActiveRecord::Schema.define(version: 20181101144347) do
     t.integer "jobs_cache_index"
     t.boolean "pages_https_only", default: true
     t.boolean "remote_mirror_available_overridden"
+    t.integer "pool_repository_id", limit: 8
   end
 
   add_index "projects", ["ci_id"], name: "index_projects_on_ci_id", using: :btree
@@ -1719,6 +1720,7 @@ ActiveRecord::Schema.define(version: 20181101144347) do
   add_index "projects", ["path"], name: "index_projects_on_path", using: :btree
   add_index "projects", ["path"], name: "index_projects_on_path_trigram", using: :gin, opclasses: {"path"=>"gin_trgm_ops"}
   add_index "projects", ["pending_delete"], name: "index_projects_on_pending_delete", using: :btree
+  add_index "projects", ["pool_repository_id"], name: "index_projects_on_pool_repository_id", where: "(pool_repository_id IS NOT NULL)", using: :btree
   add_index "projects", ["repository_storage", "created_at"], name: "idx_project_repository_check_partial", where: "(last_repository_check_at IS NULL)", using: :btree
   add_index "projects", ["repository_storage"], name: "index_projects_on_repository_storage", using: :btree
   add_index "projects", ["runners_token"], name: "index_projects_on_runners_token", using: :btree
@@ -1851,6 +1853,14 @@ ActiveRecord::Schema.define(version: 20181101144347) do
   add_index "remote_mirrors", ["last_successful_update_at"], name: "index_remote_mirrors_on_last_successful_update_at", using: :btree
   add_index "remote_mirrors", ["project_id"], name: "index_remote_mirrors_on_project_id", using: :btree
 
+  create_table "repositories", id: :bigserial, force: :cascade do |t|
+    t.integer "shard_id", null: false
+    t.string "disk_path", null: false
+  end
+
+  add_index "repositories", ["disk_path"], name: "index_repositories_on_disk_path", unique: true, using: :btree
+  add_index "repositories", ["shard_id"], name: "index_repositories_on_shard_id", using: :btree
+
   create_table "repository_languages", id: false, force: :cascade do |t|
     t.integer "project_id", null: false
     t.integer "programming_language_id", null: false
@@ -2456,6 +2466,7 @@ ActiveRecord::Schema.define(version: 20181101144347) do
   add_foreign_key "project_import_data", "projects", name: "fk_ffb9ee3a10", on_delete: :cascade
   add_foreign_key "project_mirror_data", "projects", on_delete: :cascade
   add_foreign_key "project_statistics", "projects", on_delete: :cascade
+  add_foreign_key "projects", "repositories", column: "pool_repository_id", name: "fk_6e5c14658a", on_delete: :nullify
   add_foreign_key "prometheus_metrics", "projects", on_delete: :cascade
   add_foreign_key "protected_branch_merge_access_levels", "protected_branches", name: "fk_8a3072ccb3", on_delete: :cascade
   add_foreign_key "protected_branch_push_access_levels", "protected_branches", name: "fk_9ffc86a3d9", on_delete: :cascade
@@ -2467,6 +2478,7 @@ ActiveRecord::Schema.define(version: 20181101144347) do
   add_foreign_key "push_event_payloads", "events", name: "fk_36c74129da", on_delete: :cascade
   add_foreign_key "releases", "projects", name: "fk_47fe2a0596", on_delete: :cascade
   add_foreign_key "remote_mirrors", "projects", on_delete: :cascade
+  add_foreign_key "repositories", "shards", on_delete: :restrict
   add_foreign_key "repository_languages", "projects", on_delete: :cascade
   add_foreign_key "resource_label_events", "issues", on_delete: :cascade
   add_foreign_key "resource_label_events", "labels", on_delete: :nullify

lib/gitlab/import_export/import_export.yml

@@ -92,6 +92,7 @@ excluded_attributes:
     - :path
     - :namespace_id
     - :creator_id
+    - :pool_repository_id
     - :import_url
     - :import_status
     - :avatar

spec/lib/gitlab/import_export/all_models.yml

@@ -299,6 +299,7 @@ project:
 - ci_cd_settings
 - import_export_upload
 - repository_languages
+- pool_repository
 award_emoji:
 - awardable
 - user