Allow SQL Warnings to be ignored using error codes

In rails#46690 the `db_warnings_action` and `db_warnings_ignore` configs where added. The
`db_warnings_ignore` can take a list of warning messages to match against.

At GitHub we have a subscriber that that does something like this but also filters out error codes. There might also be
other applications that filter via error codes and this could be something they can use instead of just the explicit
messages.

This also refactors the adapter tests in order for mysql2 and postgresql adapters to share the same helper when setting
the db_warnings_action and db_warnings_ignore configs

Author: nickborromeo

activerecord/CHANGELOG.md

@@ -1,3 +1,18 @@
+*   Allow warning codes to be ignore when reporting SQL warnings.
+
+    Active Record config that can ignore warning codes
+
+    ```ruby
+    # Configure allowlist of warnings that should always be ignored
+    config.active_record.db_warnings_ignore = [
+      "1062", # MySQL Error 1062: Duplicate entry
+    ]
+    ```
+
+    This is supported for the MySQL and PostgreSQL adapters.
+
+    *Nick Borromeo*
+
 *   Introduce `:active_record_fixtures` lazy load hook.
 
     Hooks defined with this name will be run whenever `TestFixtures` is included

activerecord/lib/active_record/connection_adapters/abstract_adapter.rb

@@ -1197,7 +1197,9 @@ def default_prepared_statements
         end
 
         def warning_ignored?(warning)
-          ActiveRecord.db_warnings_ignore.any? { |warning_matcher| warning.message.match?(warning_matcher) }
+          ActiveRecord.db_warnings_ignore.any? do |warning_matcher|
+            warning.message.match?(warning_matcher) || warning.code.to_s.match?(warning_matcher)
+          end
         end
     end
   end

activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb

@@ -326,55 +326,45 @@ def test_database_timezone_changes_synced_to_connection
   end
 
   def test_ignores_warnings_when_behaviour_ignore
-    ActiveRecord.db_warnings_action = :ignore
-
-    result = @conn.execute('SELECT 1 + "foo"')
-
-    assert_equal [1], result.to_a.first
-  ensure
-    ActiveRecord.db_warnings_action = @original_db_warnings_action
+    with_db_warnings_action(:ignore) do
+      result = @conn.execute('SELECT 1 + "foo"')
+      assert_equal [1], result.to_a.first
+    end
   end
 
   def test_logs_warnings_when_behaviour_log
-    ActiveRecord.db_warnings_action = :log
-
-    mysql_warning = "[ActiveRecord::SQLWarning] Truncated incorrect DOUBLE value: 'foo' (1292)"
+    with_db_warnings_action(:log) do
+      mysql_warning = "[ActiveRecord::SQLWarning] Truncated incorrect DOUBLE value: 'foo' (1292)"
 
-    assert_called_with(ActiveRecord::Base.logger, :warn, [mysql_warning]) do
-      @conn.execute('SELECT 1 + "foo"')
+      assert_called_with(ActiveRecord::Base.logger, :warn, [mysql_warning]) do
+        @conn.execute('SELECT 1 + "foo"')
+      end
     end
-  ensure
-    ActiveRecord.db_warnings_action = @original_db_warnings_action
   end
 
   def test_raises_warnings_when_behaviour_raise
-    ActiveRecord.db_warnings_action = :raise
-
-    assert_raises(ActiveRecord::SQLWarning) do
-      @conn.execute('SELECT 1 + "foo"')
+    with_db_warnings_action(:raise) do
+      assert_raises(ActiveRecord::SQLWarning) do
+        @conn.execute('SELECT 1 + "foo"')
+      end
     end
-  ensure
-    ActiveRecord.db_warnings_action = @original_db_warnings_action
   end
 
   def test_reports_when_behaviour_report
-    ActiveRecord.db_warnings_action = :report
-
-    error_reporter = ActiveSupport::ErrorReporter.new
-    subscriber = ActiveSupport::ErrorReporter::TestHelper::ErrorSubscriber.new
+    with_db_warnings_action(:report) do
+      error_reporter = ActiveSupport::ErrorReporter.new
+      subscriber = ActiveSupport::ErrorReporter::TestHelper::ErrorSubscriber.new
 
-    Rails.define_singleton_method(:error) { error_reporter }
-    Rails.error.subscribe(subscriber)
+      Rails.define_singleton_method(:error) { error_reporter }
+      Rails.error.subscribe(subscriber)
 
-    @conn.execute('SELECT 1 + "foo"')
+      @conn.execute('SELECT 1 + "foo"')
 
-    warning_event, * = subscriber.events.first
+      warning_event, * = subscriber.events.first
 
-    assert_kind_of ActiveRecord::SQLWarning, warning_event
-    assert_equal "Truncated incorrect DOUBLE value: 'foo'", warning_event.message
-  ensure
-    Rails.singleton_class.remove_method(:error)
-    ActiveRecord.db_warnings_action = @original_db_warnings_action
+      assert_kind_of ActiveRecord::SQLWarning, warning_event
+      assert_equal "Truncated incorrect DOUBLE value: 'foo'", warning_event.message
+    end
   end
 
   def test_warnings_behaviour_can_be_customized_with_a_proc
@@ -391,64 +381,68 @@ def test_warnings_behaviour_can_be_customized_with_a_proc
   end
 
   def test_allowlist_of_warnings_to_ignore
-    old_ignored_warnings = ActiveRecord.db_warnings_ignore
-    ActiveRecord.db_warnings_action = :raise
-    ActiveRecord.db_warnings_ignore = [/Truncated incorrect DOUBLE value/]
+    with_db_warnings_action(:raise, [/Truncated incorrect DOUBLE value/]) do
+      result = @conn.execute('SELECT 1 + "foo"')
 
-    result = @conn.execute('SELECT 1 + "foo"')
+      assert_equal [1], result.to_a.first
+    end
+  end
 
-    assert_equal [1], result.to_a.first
-  ensure
-    ActiveRecord.db_warnings_action = @original_db_warnings_action
-    ActiveRecord.db_warnings_ignore = old_ignored_warnings
+  def test_allowlist_of_warning_codes_to_ignore
+    with_db_warnings_action(:raise, ["1062"]) do
+      row_id = @conn.insert("INSERT INTO posts (title, body) VALUES('Title', 'Body')")
+      result = @conn.execute("INSERT IGNORE INTO posts (id, title, body) VALUES(#{row_id}, 'Title', 'Body')")
+
+      assert_nil result
+    end
   end
 
   def test_does_not_raise_note_level_warnings
-    ActiveRecord.db_warnings_action = :raise
-
-    result = @conn.execute("DROP TABLE IF EXISTS non_existent_table")
+    with_db_warnings_action(:raise) do
+      result = @conn.execute("DROP TABLE IF EXISTS non_existent_table")
 
-    assert_equal [], result.to_a
-  ensure
-    ActiveRecord.db_warnings_action = @original_db_warnings_action
+      assert_equal [], result.to_a
+    end
   end
 
   def test_warnings_do_not_change_returned_value_of_exec_update
     previous_logger = ActiveRecord::Base.logger
-    ActiveRecord::Base.logger = ActiveSupport::Logger.new(nil)
-    ActiveRecord.db_warnings_action = :log
-
-    # Mysql2 will raise an error when attempting to perform an update that warns if the sql_mode is set to strict
     old_sql_mode = @conn.query_value("SELECT @@SESSION.sql_mode")
-    @conn.execute("SET @@SESSION.sql_mode=''")
 
-    @conn.execute("INSERT INTO posts (title, body) VALUES('Title', 'Body')")
-    result = @conn.update("UPDATE posts SET title = 'Updated' WHERE id > (0+'foo') LIMIT 1")
+    with_db_warnings_action(:log) do
+      ActiveRecord::Base.logger = ActiveSupport::Logger.new(nil)
+
+      # Mysql2 will raise an error when attempting to perform an update that warns if the sql_mode is set to strict
+      @conn.execute("SET @@SESSION.sql_mode=''")
+
+      @conn.execute("INSERT INTO posts (title, body) VALUES('Title', 'Body')")
+      result = @conn.update("UPDATE posts SET title = 'Updated' WHERE id > (0+'foo') LIMIT 1")
 
-    assert_equal 1, result
+      assert_equal 1, result
+    end
   ensure
     @conn.execute("SET @@SESSION.sql_mode='#{old_sql_mode}'")
     ActiveRecord::Base.logger = previous_logger
-    ActiveRecord.db_warnings_action = @original_db_warnings_action
   end
 
   def test_warnings_do_not_change_returned_value_of_exec_delete
     previous_logger = ActiveRecord::Base.logger
-    ActiveRecord::Base.logger = ActiveSupport::Logger.new(nil)
-    ActiveRecord.db_warnings_action = :log
-
-    # Mysql2 will raise an error when attempting to perform a delete that warns if the sql_mode is set to strict
     old_sql_mode = @conn.query_value("SELECT @@SESSION.sql_mode")
-    @conn.execute("SET @@SESSION.sql_mode=''")
 
-    @conn.execute("INSERT INTO posts (title, body) VALUES('Title', 'Body')")
-    result = @conn.delete("DELETE FROM posts WHERE id > (0+'foo') LIMIT 1")
+    with_db_warnings_action(:log) do
+      ActiveRecord::Base.logger = ActiveSupport::Logger.new(nil)
+
+      # Mysql2 will raise an error when attempting to perform a delete that warns if the sql_mode is set to strict
+      @conn.execute("SET @@SESSION.sql_mode=''")
+
+      @conn.execute("INSERT INTO posts (title, body) VALUES('Title', 'Body')")
+      result = @conn.delete("DELETE FROM posts WHERE id > (0+'foo') LIMIT 1")
 
-    assert_equal 1, result
+      assert_equal 1, result
+    end
   ensure
     @conn.execute("SET @@SESSION.sql_mode='#{old_sql_mode}'")
     ActiveRecord::Base.logger = previous_logger
-    ActiveRecord.db_warnings_action = @original_db_warnings_action
   end
 
   private

activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb

@@ -589,6 +589,15 @@ def test_allowlist_of_warnings_to_ignore
         end
       end
 
+      def test_allowlist_of_warning_codes_to_ignore
+        with_example_table do
+          with_db_warnings_action(:raise, ["01000"]) do
+            result = @connection.execute("do $$ BEGIN RAISE WARNING 'PostgreSQL SQL warning'; END; $$")
+            assert_equal [], result.to_a
+          end
+        end
+      end
+
       def test_does_not_raise_notice_level_warnings
         with_db_warnings_action(:raise, [/PostgreSQL SQL warning/]) do
           result = @connection.execute("DROP TABLE IF EXISTS non_existent_table")
@@ -606,20 +615,6 @@ def connection_without_insert_returning
           db_config = ActiveRecord::Base.configurations.configs_for(env_name: "arunit", name: "primary")
           ActiveRecord::Base.postgresql_connection(db_config.configuration_hash.merge(insert_returning: false))
         end
-
-        def with_db_warnings_action(action, warnings_to_ignore = [])
-          original_db_warnings_ignore = ActiveRecord.db_warnings_ignore
-
-          ActiveRecord.db_warnings_action = action
-          ActiveRecord.db_warnings_ignore = warnings_to_ignore
-          @connection.disconnect! # Disconnect from the db so that we reconfigure the connection
-
-          yield
-        ensure
-          ActiveRecord.db_warnings_action = @original_db_warnings_action
-          ActiveRecord.db_warnings_ignore = original_db_warnings_ignore
-          @connection.disconnect!
-        end
     end
   end
 end

activerecord/test/cases/test_case.rb

@@ -115,6 +115,21 @@ def with_automatic_scope_inversing(*reflections)
       end
     end
 
+    def with_db_warnings_action(action, warnings_to_ignore = [])
+      original_db_warnings_ignore = ActiveRecord.db_warnings_ignore
+
+      ActiveRecord.db_warnings_action = action
+      ActiveRecord.db_warnings_ignore = warnings_to_ignore
+
+      ActiveRecord::Base.connection.disconnect! # Disconnect from the db so that we reconfigure the connection
+
+      yield
+    ensure
+      ActiveRecord.db_warnings_action = @original_db_warnings_action
+      ActiveRecord.db_warnings_ignore = original_db_warnings_ignore
+      ActiveRecord::Base.connection.disconnect!
+    end
+
     def reset_callbacks(klass, kind)
       old_callbacks = {}
       old_callbacks[klass] = klass.send("_#{kind}_callbacks").dup

guides/source/configuring.md

@@ -1023,7 +1023,7 @@ Controls the action to be taken when a SQL query produces a warning. The followi
 
 #### `config.active_record.db_warnings_ignore`
 
-Specifies an allowlist of warnings that will be ignored, regardless of the configured `db_warnings_action`.
+Specifies an allowlist of warning codes and messages that will be ignored, regardless of the configured `db_warnings_action`.
 The default behavior is to report all warnings. Warnings to ignore can be specified as Strings or Regexps. For example:
 
   ```ruby
@@ -1032,6 +1032,7 @@ The default behavior is to report all warnings. Warnings to ignore can be specif
   config.active_record.db_warnings_ignore = [
     /Invalid utf8mb4 character string/,
     "An exact warning message",
+    "1062", # MySQL Error 1062: Duplicate entry
   ]
   ```