Add AR::TransactionSerializationError for transaction serialization failures or deadlocks

3 files changed, 24 insertions, 3 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
index 0f565277e3..44b4b547f3 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -727,14 +727,22 @@ module ActiveRecord
         column_names.map {|name| quote_column_name(name) + option_strings[name]}
       end
 
+      # See https://dev.mysql.com/doc/refman/5.7/en/error-messages-server.html
+      ER_DUP_ENTRY            = 1062
+      ER_NO_REFERENCED_ROW_2  = 1452
+      ER_DATA_TOO_LONG        = 1406
+      ER_LOCK_DEADLOCK        = 1213
+
       def translate_exception(exception, message)
         case error_number(exception)
-        when 1062
+        when ER_DUP_ENTRY
           RecordNotUnique.new(message)
-        when 1452
+        when ER_NO_REFERENCED_ROW_2
           InvalidForeignKey.new(message)
-        when 1406
+        when ER_DATA_TOO_LONG
           ValueTooLong.new(message)
+        when ER_LOCK_DEADLOCK
+          TransactionSerializationError.new(message)
         else
           super
         end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index bab80a8890..ddfc560747 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -406,6 +406,7 @@ module ActiveRecord
         VALUE_LIMIT_VIOLATION = "22001"
         FOREIGN_KEY_VIOLATION = "23503"
         UNIQUE_VIOLATION      = "23505"
+        SERIALIZATION_FAILURE = "40001"
 
         def translate_exception(exception, message)
           return exception unless exception.respond_to?(:result)
@@ -417,6 +418,8 @@ module ActiveRecord
             InvalidForeignKey.new(message)
           when VALUE_LIMIT_VIOLATION
             ValueTooLong.new(message)
+          when SERIALIZATION_FAILURE
+            TransactionSerializationError.new(message)
           else
             super
           end
diff --git a/activerecord/lib/active_record/errors.rb b/activerecord/lib/active_record/errors.rb
index b8b8684cff..38e4fbec8b 100644
--- a/activerecord/lib/active_record/errors.rb
+++ b/activerecord/lib/active_record/errors.rb
@@ -285,6 +285,16 @@ module ActiveRecord
   class TransactionIsolationError < ActiveRecordError
   end
 
+  # TransactionSerializationError will be raised when a transaction is rolled
+  # back by the database due to a serialization failure or a deadlock.
+  #
+  # See the following:
+  #
+  # * http://www.postgresql.org/docs/current/static/transaction-iso.html
+  # * https://dev.mysql.com/doc/refman/5.7/en/error-messages-server.html#error_er_lock_deadlock
+  class TransactionSerializationError < ActiveRecordError
+  end
+
   # IrreversibleOrderError is raised when a relation's order is too complex for
   # +reverse_order+ to automatically reverse.
   class IrreversibleOrderError < ActiveRecordError