feat: add multi database support

Author: seuros

.github/workflows/ci.yml

@@ -50,7 +50,7 @@ jobs:
           - activerecord_6.1
           - activerecord_edge
         adapter:
-          - 'sqlite3:///:memory:'
+          - '' # SQLite3
           - mysql2://root:root@0/closure_tree_test
           - postgres://closure_tree:closure_tree@0/closure_tree_test
         exclude:
@@ -59,7 +59,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Setup Ruby
         uses: ruby/setup-ruby@v1
@@ -74,7 +74,8 @@ jobs:
       - name: RSpec
         env:
           RAILS_VERSION: ${{ matrix.rails }}
-          DB_ADAPTER: ${{ matrix.adapter }}
+          DATABASE_URL: ${{ matrix.adapter }}
+          SECONDARY_DATABASE_URL: ${{ matrix.adapter }}
           BUNDLE_GEMFILE: gemfiles/${{ matrix.rails }}.gemfile
           WITH_ADVISORY_LOCK_PREFIX: ${{ github.run_id }}
         run: bin/rake

.github/workflows/ci_jruby.yml

@@ -43,12 +43,12 @@ jobs:
           - activerecord_7.0
           - activerecord_6.1
         adapter:
-          - 'sqlite3:///:memory:'
+          - '' # SQLite3
           - mysql2://root:root@0/closure_tree_test
           - postgres://closure_tree:closure_tree@0/closure_tree_test
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Setup Ruby
         uses: ruby/setup-ruby@v1
@@ -63,7 +63,8 @@ jobs:
       - name: RSpec
         env:
           RAILS_VERSION: ${{ matrix.rails }}
-          DB_ADAPTER: ${{ matrix.adapter }}
+          DATABASE_URL: ${{ matrix.adapter }}
+          SECONDARY_DATABASE_URL: ${{ matrix.adapter }}
           BUNDLE_GEMFILE: gemfiles/${{ matrix.rails }}.gemfile
           WITH_ADVISORY_LOCK_PREFIX: ${{ github.run_id }}
         run: bin/rake

.github/workflows/ci_truffleruby.yml

@@ -45,13 +45,13 @@ jobs:
           - activerecord_7.0
           - activerecord_6.1
         adapter:
-          - 'sqlite3:///:memory:'
+          - '' # SQLite3
           - mysql2://root:root@0/closure_tree_test
           - postgres://closure_tree:closure_tree@0/closure_tree_test
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Setup Ruby
         uses: ruby/setup-ruby@v1
@@ -66,7 +66,8 @@ jobs:
       - name: RSpec
         env:
           RAILS_VERSION: ${{ matrix.rails }}
-          DB_ADAPTER: ${{ matrix.adapter }}
+          DATABASE_URL: ${{ matrix.adapter }}
+          SECONDARY_DATABASE_URL: ${{ matrix.adapter }}
           BUNDLE_GEMFILE: gemfiles/${{ matrix.rails }}.gemfile
           WITH_ADVISORY_LOCK_PREFIX: ${{ github.run_id }}
         run: bin/rake

lib/closure_tree/support_attributes.rb

@@ -117,7 +117,7 @@ def quoted_order_column(include_table_name = true)
 
     # table_name alias keyword , like "AS". When used on table name alias, Oracle Database don't support used 'AS'
     def t_alias_keyword
-      (ActiveRecord::Base.connection.adapter_name.to_sym == :OracleEnhanced) ? "" : "AS"
+      (connection.adapter_name.to_sym == :OracleEnhanced) ? "" : "AS"
     end
   end
 end

spec/spec_helper.rb

@@ -20,9 +20,14 @@
   end
 end
 
+database_file = SecureRandom.hex
 ActiveRecord::Base.configurations = {
   default_env: {
-    url: ENV.fetch('DATABASE_URL', "sqlite3::memory:"),
+    url: ENV['DATABASE_URL'].presence || "sqlite3://#{Dir.tmpdir}/#{database_file}.sqlite3",
+    properties: { allowPublicKeyRetrieval: true } # for JRuby madness
+  },
+  secondary_env: {
+    url: ENV['SECONDARY_DATABASE_URL'].presence || "sqlite3://#{Dir.tmpdir}/#{database_file}-s.sqlite3",
     properties: { allowPublicKeyRetrieval: true } # for JRuby madness
   }
 }

spec/support/exceed_query_limit.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Derived from http://stackoverflow.com/a/13423584/153896. Updated for RSpec 3.
 RSpec::Matchers.define :exceed_query_limit do |expected|
   supports_block_expectations
@@ -6,7 +8,7 @@
     query_count(&block) > expected
   end
 
-  failure_message_when_negated do |actual|
+  failure_message_when_negated do |_actual|
     "Expected to run maximum #{expected} queries, got #{@counter.query_count}"
   end
 

spec/support/helpers.rb

@@ -1,7 +1,9 @@
+# frozen_string_literal: true
+
 # See http://stackoverflow.com/a/22388177/1268016
 def count_queries(&block)
   count = 0
-  counter_fn = ->(name, started, finished, unique_id, payload) do
+  counter_fn = lambda do |_name, _started, _finished, _unique_id, payload|
     count += 1 unless %w[CACHE SCHEMA].include? payload[:name]
   end
   ActiveSupport::Notifications.subscribed(counter_fn, 'sql.active_record', &block)

spec/support/models.rb

@@ -1,9 +1,5 @@
 # frozen_string_literal: true
 
-class ApplicationRecord < ActiveRecord::Base
-  self.abstract_class = true
-end
-
 class Tag < ApplicationRecord
   has_closure_tree dependent: :destroy, order: :name
   before_destroy :add_destroyed_tag
@@ -146,6 +142,6 @@ class Adamantium < Metal
 class Unobtanium < Metal
 end
 
-class MenuItem < ApplicationRecord
+class MenuItem < SecondDatabaseRecord
   has_closure_tree touch: true, with_advisory_lock: false
 end

spec/support/query_counter.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # From http://stackoverflow.com/a/13423584/153896
 module ActiveRecord
   class QueryCounter
@@ -11,8 +13,8 @@ def to_proc
       lambda(&method(:callback))
     end
 
-    def callback(name, start, finish, message_id, values)
-      @query_count += 1 unless %w(CACHE SCHEMA).include?(values[:name])
+    def callback(_name, _start, _finish, _message_id, values)
+      @query_count += 1 unless %w[CACHE SCHEMA].include?(values[:name])
     end
   end
 end

spec/support/schema.rb

@@ -1,7 +1,17 @@
 # frozen_string_literal: true
 
+class ApplicationRecord < ActiveRecord::Base
+  self.abstract_class = true
+end
+
+class SecondDatabaseRecord < ActiveRecord::Base
+  self.abstract_class = true
+
+  establish_connection :secondary_env
+end
+
 ActiveRecord::Schema.define(version: 0) do
-  create_table 'tags', force: :cascade do |t|
+  connection.create_table 'tags', force: :cascade do |t|
     t.string 'name'
     t.string 'title'
     t.references 'parent'
@@ -126,18 +136,6 @@
     t.integer 'generations', null: false
   end
 
-  create_table 'menu_items', force: :cascade do |t|
-    t.string 'name'
-    t.references 'parent'
-    t.timestamps null: false
-  end
-
-  create_table 'menu_item_hierarchies', id: false, force: :cascade do |t|
-    t.references 'ancestor', null: false
-    t.references 'descendant', null: false
-    t.integer 'generations', null: false
-  end
-
   add_index 'label_hierarchies', %i[ancestor_id descendant_id generations], unique: true,
                                                                             name: 'lh_anc_desc_idx'
   add_index 'label_hierarchies', [:descendant_id], name: 'lh_desc_idx'
@@ -149,9 +147,25 @@
   add_foreign_key(:users, :users, column: 'referrer_id', on_delete: :cascade)
   add_foreign_key(:labels, :labels, column: 'mother_id', on_delete: :cascade)
   add_foreign_key(:metal, :metal, column: 'parent_id', on_delete: :cascade)
-  add_foreign_key(:menu_items, :menu_items, column: 'parent_id', on_delete: :cascade)
-  add_foreign_key(:menu_item_hierarchies, :menu_items, column: 'ancestor_id', on_delete: :cascade)
-  add_foreign_key(:menu_item_hierarchies, :menu_items, column: 'descendant_id', on_delete: :cascade)
   add_foreign_key(:tag_hierarchies, :tags, column: 'ancestor_id', on_delete: :cascade)
   add_foreign_key(:tag_hierarchies, :tags, column: 'descendant_id', on_delete: :cascade)
 end
+
+SecondDatabaseRecord.connection_pool.with_connection do |connection|
+  ActiveRecord::Schema.define(version: 0) do
+    connection.create_table 'menu_items', force: :cascade do |t|
+      t.string 'name'
+      t.references 'parent'
+      t.timestamps null: false
+    end
+
+    connection.create_table 'menu_item_hierarchies', id: false, force: :cascade do |t|
+      t.references 'ancestor', null: false
+      t.references 'descendant', null: false
+      t.integer 'generations', null: false
+    end
+    connection.add_foreign_key(:menu_items, :menu_items, column: 'parent_id', on_delete: :cascade)
+    connection.add_foreign_key(:menu_item_hierarchies, :menu_items, column: 'ancestor_id', on_delete: :cascade)
+    connection.add_foreign_key(:menu_item_hierarchies, :menu_items, column: 'descendant_id', on_delete: :cascade)
+  end
+end

test/closure_tree/model_test.rb

@@ -7,3 +7,18 @@
     assert_equal Tag._ct, Tag.new._ct
   end
 end
+
+describe "multi database support" do
+  it 'should have a different connection for menu items' do
+    # These 2 models are in the same database
+    assert_equal Tag.connection, Metal.connection
+    # The hierarchy table is in the same database
+    assert_equal Tag.connection, TagHierarchy.connection
+
+    # However, these 2 models are in different databases
+    refute_equal MenuItem.connection, Tag.connection
+    # The hierarchy table is in the same database
+    assert_equal MenuItem.connection, MenuItemHierarchy.connection
+  end
+
+end

test/test_helper.rb

@@ -1,19 +1,20 @@
 # frozen_string_literal: true
 
-require 'erb'
 require 'active_record'
-require 'with_advisory_lock'
-require 'tmpdir'
-require 'securerandom'
 require 'minitest'
 require 'minitest/autorun'
 require 'database_cleaner'
 require 'support/query_counter'
 require 'parallel'
 
+database_file = SecureRandom.hex
 ActiveRecord::Base.configurations = {
   default_env: {
-    url: ENV.fetch('DATABASE_URL', "sqlite3://#{Dir.tmpdir}/#{SecureRandom.hex}.sqlite3"),
+    url: ENV['DATABASE_URL'].presence || "sqlite3://#{Dir.tmpdir}/#{database_file}.sqlite3",
+    properties: { allowPublicKeyRetrieval: true } # for JRuby madness
+  },
+  secondary_env: {
+    url: ENV['SECONDARY_DATABASE_URL'].presence || "sqlite3://#{Dir.tmpdir}/#{database_file}-s.sqlite3",
     properties: { allowPublicKeyRetrieval: true } # for JRuby madness
   }
 }
@@ -23,11 +24,7 @@
 ActiveRecord::Base.establish_connection
 
 def env_db
-  @env_db ||= if ActiveRecord::Base.respond_to?(:connection_db_config)
-                ActiveRecord::Base.connection_db_config.adapter
-              else
-                ActiveRecord::Base.connection_config[:adapter]
-              end.to_sym
+  @env_db ||= ActiveRecord::Base.connection_db_config.adapter.to_sym
 end
 
 ActiveRecord::Migration.verbose = false
@@ -40,7 +37,6 @@ def sqlite?
   env_db == :sqlite3
 end
 
-ActiveRecord::Base.connection.recreate_database('closure_tree_test') unless sqlite?
 puts "Testing with #{env_db} database, ActiveRecord #{ActiveRecord.gem_version} and #{RUBY_ENGINE} #{RUBY_ENGINE_VERSION} as #{RUBY_VERSION}"
 
 DatabaseCleaner.strategy = :truncation
@@ -67,3 +63,4 @@ class Spec
 require 'closure_tree'
 require_relative '../spec/support/schema'
 require_relative '../spec/support/models'
+ActiveRecord::Base.connection.recreate_database('closure_tree_test') unless sqlite?