Pass the transaction to the transaction.active_record event

Author: fxn

activerecord/lib/active_record/connection_adapters/abstract/transaction.rb

@@ -141,7 +141,7 @@ def initialize(connection, isolation: nil, joinable: true, run_commit_callbacks:
         @run_commit_callbacks = run_commit_callbacks
         @lazy_enrollment_records = nil
         @dirty = false
-        @instrumenter = TransactionInstrumenter.new(connection: connection)
+        @instrumenter = TransactionInstrumenter.new(connection: connection, transaction: self)
       end
 
       def dirty!

activerecord/test/cases/transaction_instrumentation_test.rb

@@ -11,13 +11,17 @@ def test_transaction_instrumentation_on_commit
     topic = topics(:fifth)
 
     notified = false
+    expected_transaction = nil
+
     subscriber = ActiveSupport::Notifications.subscribe("transaction.active_record") do |event|
       assert event.payload[:connection]
+      assert_same expected_transaction, event.payload[:transaction]
       assert_equal :commit, event.payload[:outcome]
       notified = true
     end
 
-    ActiveRecord::Base.transaction do
+    ActiveRecord::Base.transaction do |transaction|
+      expected_transaction = transaction
       topic.update(title: "Ruby on Rails")
     end
 
@@ -30,13 +34,17 @@ def test_transaction_instrumentation_on_rollback
     topic = topics(:fifth)
 
     notified = false
+    expected_transaction = nil
+
     subscriber = ActiveSupport::Notifications.subscribe("transaction.active_record") do |event|
       assert event.payload[:connection]
+      assert_same expected_transaction, event.payload[:transaction]
       assert_equal :rollback, event.payload[:outcome]
       notified = true
     end
 
-    ActiveRecord::Base.transaction do
+    ActiveRecord::Base.transaction do |transaction|
+      expected_transaction = transaction
       topic.update(title: "Ruby on Rails")
       raise ActiveRecord::Rollback
     end
@@ -54,17 +62,24 @@ def test_transaction_instrumentation_with_savepoints
       events << event
     end
 
-    ActiveRecord::Base.transaction do
+    real_transaction = savepoint_transaction = nil
+    ActiveRecord::Base.transaction do |transaction|
+      real_transaction = transaction
       topic.update(title: "Sinatra")
-      ActiveRecord::Base.transaction(requires_new: true) do
+      ActiveRecord::Base.transaction(requires_new: true) do |transaction|
+        savepoint_transaction = transaction
         topic.update(title: "Ruby on Rails")
       end
     end
 
     assert_equal 2, events.count
-    savepoint, real = events
-    assert_equal :commit, savepoint.payload[:outcome]
-    assert_equal :commit, real.payload[:outcome]
+    savepoint_event, real_event = events
+
+    assert_same savepoint_transaction, savepoint_event.payload[:transaction]
+    assert_equal :commit, savepoint_event.payload[:outcome]
+
+    assert_same real_transaction, real_event.payload[:transaction]
+    assert_equal :commit, real_event.payload[:outcome]
   ensure
     ActiveSupport::Notifications.unsubscribe(subscriber) if subscriber
   end

guides/source/active_support_instrumentation.md

@@ -413,6 +413,7 @@ This event is emmited for every transaction to the database.
 | Key                  | Value                                                |
 | -------------------- | ---------------------------------------------------- |
 | `:connection`        | Connection object                                    |
+| `:transaction`       | Transaction object
 | `:outcome`           | `:commit`, `:rollback`, `:restart`, or `:incomplete` |
 
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