Implicit Order Column value checker

README.md

@@ -84,6 +84,7 @@ ForeignKeyTypeChecker fail User something association (something) of class (User
 ThreeStateBooleanChecker fail Company active boolean column should have NOT NULL constraint
 MissingAssociationClassChecker fail Company anything refers to undefined model "Anything"
 MissingTableChecker fail LegacyModel should have a table in the database
+ImplicitOrderingChecker fail Secondary::User id implicit_order_column is recommended when using uuid column type for primary key
 ```
 
 ## Funding

lib/database_consistency.rb

@@ -42,6 +42,7 @@
 require 'database_consistency/writers/simple/three_state_boolean'
 require 'database_consistency/writers/simple/missing_association_class'
 require 'database_consistency/writers/simple/missing_table'
+require 'database_consistency/writers/simple/implicit_order_column_missing'
 require 'database_consistency/writers/simple_writer'
 
 require 'database_consistency/writers/autofix/helpers/migration'
@@ -80,6 +81,7 @@
 require 'database_consistency/checkers/column_checkers/primary_key_type_checker'
 require 'database_consistency/checkers/column_checkers/enum_value_checker'
 require 'database_consistency/checkers/column_checkers/three_state_boolean_checker'
+require 'database_consistency/checkers/column_checkers/implicit_ordering_checker.rb'
 
 require 'database_consistency/checkers/validator_checkers/validator_checker'
 require 'database_consistency/checkers/validator_checkers/missing_unique_index_checker'

lib/database_consistency/checkers/column_checkers/implicit_ordering_checker.rb

@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+module DatabaseConsistency
+  module Checkers
+    # This class checks that primary column type is "uuid" and the model class defines `self.implicit_order_column`
+    class ImplicitOrderingChecker < ColumnChecker
+      Report = ReportBuilder.define(DatabaseConsistency::Report)
+
+      private
+
+      TARGET_COLUMN_TYPE = 'uuid'
+
+      # We skip check when:
+      # - adapter is not PostgreSQL
+      # - column is not a primary key
+      # - column type is not "uuid"
+      def preconditions
+        ActiveRecord::VERSION::MAJOR >= 6 &&
+          Helper.postgresql? &&
+          primary_field? &&
+          column.sql_type.to_s.match(TARGET_COLUMN_TYPE)
+      end
+
+      # Table of possible statuses
+      # | defined `self.implicit_order_column` | status |
+      # | ----------------------------------- | ------ |
+      # | yes                                 | ok     |
+      # | no                                  | fail   |
+      def check
+        if implicit_order_column_defined?
+          report_template(:ok)
+        else
+          report_template(:fail, error_slug: :implicit_order_column_missing)
+        end
+      end
+
+      # @return [Boolean]
+      def primary_field?
+        column.name.to_s == model.primary_key.to_s
+      end
+
+      # @return [Boolean]
+      def implicit_order_column_defined?
+        model.implicit_order_column.present?
+      end
+    end
+  end
+end

lib/database_consistency/processors/columns_processor.rb

@@ -9,7 +9,8 @@ class ColumnsProcessor < BaseProcessor
         Checkers::LengthConstraintChecker,
         Checkers::PrimaryKeyTypeChecker,
         Checkers::EnumValueChecker,
-        Checkers::ThreeStateBooleanChecker
+        Checkers::ThreeStateBooleanChecker,
+        Checkers::ImplicitOrderingChecker
       ].freeze
 
       private

lib/database_consistency/report_builder.rb

@@ -7,7 +7,7 @@ def self.define(klass, *attrs)
         attr_reader(*attrs)
 
         class_eval(<<~DEF, __FILE__, __LINE__ + 1)
-          def initialize(#{attrs.map { |attr| "#{attr}:" }.join(', ')}, **opts)
+          def initialize(#{attrs.map { |attr| "#{attr}:" }.join(', ')}#{"," if attrs.any?} **opts)
             super(**opts) if opts.any?
             #{attrs.map { |attr| "@#{attr} = #{attr}" }.join("\n")}
           end

lib/database_consistency/writers/simple/implicit_order_column_missing.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+module DatabaseConsistency
+  module Writers
+    module Simple
+      class ImplicitOrderColumnMissing < Base # :nodoc:
+        private
+
+        def template
+          'implicit_order_column is recommended when using uuid column type for primary key'
+        end
+
+        def unique_attributes
+          {
+            table_or_model_name: report.table_or_model_name,
+            column_or_attribute_name: report.column_or_attribute_name
+          }
+        end
+      end
+    end
+  end
+end

lib/database_consistency/writers/simple_writer.rb

@@ -12,6 +12,7 @@ class SimpleWriter < BaseWriter
         enum_values_inconsistent_with_ar_enum: Simple::EnumValuesInconsistentWithArEnum,
         enum_values_inconsistent_with_inclusion: Simple::EnumValuesInconsistentWithInclusion,
         has_one_missing_unique_index: Simple::HasOneMissingUniqueIndex,
+        implicit_order_column_missing: Simple::ImplicitOrderColumnMissing,
         inconsistent_enum_type: Simple::InconsistentEnumType,
         inconsistent_types: Simple::InconsistentTypes,
         length_validator_greater_limit: Simple::LengthValidatorGreaterLimit,

rails7-example/Gemfile

@@ -5,6 +5,8 @@ ruby "3.2.0"
 
 gem 'database_consistency', path: '../', group: :development, require: false
 
+gem "pg"
+
 # Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main"
 gem "rails", "~> 7.0.6"
 

rails7-example/app/models/secondary/user.rb

@@ -0,0 +1,2 @@
+class Secondary::User < SecondaryRecord
+end

rails7-example/config/.database.postgresql.yml

@@ -0,0 +1,16 @@
+default: &default
+  adapter: postgresql
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+  timeout: 5000
+  username: test
+  password: password
+  host: localhost
+
+development:
+  primary:
+    <<: *default
+    database: development
+  secondary:
+    <<: *default
+    database: development_secondary
+    migrations_paths: db/migrate_secondary

rails7-example/config/.database.sqlite.yml

@@ -0,0 +1,30 @@
+# SQLite. Versions 3.8.0 and up are supported.
+#   gem install sqlite3
+#
+#   Ensure the SQLite 3 gem is defined in your Gemfile
+#   gem "sqlite3"
+#
+default: &default
+  adapter: sqlite3
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+  timeout: 5000
+
+development:
+  primary:
+    <<: *default
+    database: db/development.sqlite3
+  secondary:
+    <<: *default
+    database: db/development_secondary.sqlite3
+    migrations_paths: db/migrate_secondary
+
+# Warning: The database defined as "test" will be erased and
+# re-generated from your development database when you run "rake".
+# Do not set this db to the same as development or production.
+test:
+  <<: *default
+  database: db/test.sqlite3
+
+production:
+  <<: *default
+  database: db/production.sqlite3

rails7-example/config/database.yml

@@ -1,30 +1,16 @@
-# SQLite. Versions 3.8.0 and up are supported.
-#   gem install sqlite3
-#
-#   Ensure the SQLite 3 gem is defined in your Gemfile
-#   gem "sqlite3"
-#
 default: &default
-  adapter: sqlite3
+  adapter: postgresql
   pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
   timeout: 5000
+  username: test
+  password: password
+  host: localhost
 
 development:
   primary:
     <<: *default
-    database: db/development.sqlite3
+    database: development
   secondary:
     <<: *default
-    database: db/development_secondary.sqlite3
+    database: development_secondary
     migrations_paths: db/migrate_secondary
-
-# Warning: The database defined as "test" will be erased and
-# re-generated from your development database when you run "rake".
-# Do not set this db to the same as development or production.
-test:
-  <<: *default
-  database: db/test.sqlite3
-
-production:
-  <<: *default
-  database: db/production.sqlite3

rails7-example/db/migrate_secondary/20230722090559_create_users.rb

@@ -0,0 +1,7 @@
+class CreateUsers < ActiveRecord::Migration[7.0]
+  def change
+    create_table :users, id: :uuid do |t|
+      t.timestamps
+    end
+  end
+end

rails7-example/db/schema.rb

@@ -11,6 +11,9 @@
 # It's strongly recommended that you check this file into your version control system.
 
 ActiveRecord::Schema[7.0].define(version: 2021_12_29_101039) do
+  # These are extensions that must be enabled in order to support this database
+  enable_extension "plpgsql"
+
   create_table "companies", force: :cascade do |t|
     t.boolean "available", default: false, null: false
     t.boolean "active"
@@ -26,8 +29,10 @@
     t.datetime "updated_at", null: false
   end
 
-# Could not dump table "organizations" because of following StandardError
-#   Unknown type 'bigserial' for column 'id'
+  create_table "organizations", force: :cascade do |t|
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+  end
 
   create_table "users", force: :cascade do |t|
     t.string "email", null: false
@@ -36,7 +41,7 @@
     t.string "address"
     t.string "code", null: false
     t.string "slug", null: false
-    t.integer "company_id", limit: 8, null: false
+    t.bigint "company_id", null: false
     t.integer "country_id"
     t.integer "organization_id", null: false
     t.integer "invitable_id", null: false

rails7-example/db/secondary_schema.rb

@@ -10,9 +10,17 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.0].define(version: 2019_10_12_163944) do
+ActiveRecord::Schema[7.0].define(version: 2023_07_22_090559) do
+  # These are extensions that must be enabled in order to support this database
+  enable_extension "plpgsql"
+
   create_table "companies", force: :cascade do |t|
     t.string "name", null: false
   end
 
+  create_table "users", id: :uuid, default: -> { "gen_random_uuid()" }, force: :cascade do |t|
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+  end
+
 end

spec/checkers/implicit_ordering_checker_spec.rb

@@ -0,0 +1,67 @@
+# frozen_string_literal: true
+
+RSpec.describe DatabaseConsistency::Checkers::ImplicitOrderingChecker, :postgresql do
+  subject(:checker) { described_class.new(model, column) }
+
+  let(:klass) { define_class { |klass| klass.primary_key = :id } }
+  let(:model) { klass }
+  let(:column) { klass.columns.first }
+
+  before do
+    skip if ActiveRecord::VERSION::MAJOR < 6
+  end
+
+  context 'when primary key type is uuid and model defines self.implicit_order_column' do
+    before do
+      define_database do
+        create_table :entities, id: :uuid
+      end
+
+      klass.class_eval do
+        self.implicit_order_column = :created_at
+      end
+    end
+
+    specify do
+      expect(checker.report).to have_attributes(
+        checker_name: 'ImplicitOrderingChecker',
+        table_or_model_name: klass.name,
+        column_or_attribute_name: 'id',
+        status: :ok,
+        error_slug: nil,
+        error_message: nil
+      )
+    end
+  end
+
+  context 'when primary key type is uuid and model does not define self.implicit_order_column' do
+    before do
+      define_database do
+        create_table :entities, id: :uuid
+      end
+    end
+
+    specify do
+      expect(checker.report).to have_attributes(
+        checker_name: 'ImplicitOrderingChecker',
+        table_or_model_name: klass.name,
+        column_or_attribute_name: 'id',
+        status: :fail,
+        error_slug: :implicit_order_column_missing,
+        error_message: nil
+      )
+    end
+  end
+
+  context 'when primary key type is not uuid' do
+    before do
+      define_database do
+        create_table :entities, id: :bigint
+      end
+    end
+
+    specify do
+      expect(checker.report).to be_nil
+    end
+  end
+end