Merge pull request #25093 from Erol/activerecord-transaction-serialization-error

Introduce AR::TransactionSerializationError for transaction serialization failures or deadlocks

2 files changed, 134 insertions, 0 deletions

diff --git a/activerecord/test/cases/adapters/mysql2/transaction_test.rb b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
new file mode 100644
index 0000000000..0e37c70e5c
--- /dev/null
+++ b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
@@ -0,0 +1,62 @@
+require "cases/helper"
+require 'support/connection_helper'
+
+module ActiveRecord
+  class Mysql2TransactionTest < ActiveRecord::Mysql2TestCase
+    self.use_transactional_tests = false
+
+    class Sample < ActiveRecord::Base
+      self.table_name = 'samples'
+    end
+
+    setup do
+      @connection = ActiveRecord::Base.connection
+      @connection.clear_cache!
+
+      @connection.transaction do
+        @connection.drop_table 'samples', if_exists: true
+        @connection.create_table('samples') do |t|
+          t.integer 'value'
+        end
+      end
+
+      Sample.reset_column_information
+    end
+
+    teardown do
+      @connection.drop_table 'samples', if_exists: true
+    end
+
+    test "raises error when a serialization failure occurs" do
+      assert_raises(ActiveRecord::TransactionSerializationError) do
+        thread = Thread.new do
+          Sample.transaction isolation: :serializable do
+            Sample.delete_all
+
+            10.times do |i|
+              sleep 0.1
+
+              Sample.create value: i
+            end
+          end
+        end
+
+        sleep 0.1
+
+        Sample.transaction isolation: :serializable do
+          Sample.delete_all
+
+          10.times do |i|
+            sleep 0.1
+
+            Sample.create value: i
+          end
+
+          sleep 1
+        end
+
+        thread.join
+      end
+    end
+  end
+end
diff --git a/activerecord/test/cases/adapters/postgresql/transaction_test.rb b/activerecord/test/cases/adapters/postgresql/transaction_test.rb
new file mode 100644
index 0000000000..e76705a802
--- /dev/null
+++ b/activerecord/test/cases/adapters/postgresql/transaction_test.rb
@@ -0,0 +1,72 @@
+require "cases/helper"
+require 'support/connection_helper'
+
+module ActiveRecord
+  class PostgresqlTransactionTest < ActiveRecord::PostgreSQLTestCase
+    self.use_transactional_tests = false
+
+    class Sample < ActiveRecord::Base
+      self.table_name = 'samples'
+    end
+
+    setup do
+      @connection = ActiveRecord::Base.connection
+
+      @connection.transaction do
+        @connection.drop_table 'samples', if_exists: true
+        @connection.create_table('samples') do |t|
+          t.integer 'value'
+        end
+      end
+
+      Sample.reset_column_information
+    end
+
+    teardown do
+      @connection.drop_table 'samples', if_exists: true
+    end
+
+    test "raises error when a serialization failure occurs" do
+      with_warning_suppression do
+        assert_raises(ActiveRecord::TransactionSerializationError) do
+          thread = Thread.new do
+            Sample.transaction isolation: :serializable do
+              Sample.delete_all
+
+              10.times do |i|
+                sleep 0.1
+
+                Sample.create value: i
+              end
+            end
+          end
+
+          sleep 0.1
+
+          Sample.transaction isolation: :serializable do
+            Sample.delete_all
+
+            10.times do |i|
+              sleep 0.1
+
+              Sample.create value: i
+            end
+
+            sleep 1
+          end
+
+          thread.join
+        end
+      end
+    end
+
+    protected
+
+    def with_warning_suppression
+      log_level = @connection.client_min_messages
+      @connection.client_min_messages = 'error'
+      yield
+      @connection.client_min_messages = log_level
+    end
+  end
+end