Bug #44331 Restore of database with events produces warning in replication

If an EVENT is created without the DEFINER clause set explicitly or with it set  
to CURRENT_USER, the master and slaves become inconsistent. This issue stems from 
the fact that in both cases, the DEFINER is set to the CURRENT_USER of the current 
thread. On the master, the CURRENT_USER is the mysqld's user, while on the slave,  
the CURRENT_USER is empty for the SQL Thread which is responsible for executing 
the statement.

To fix the problem, we do what follows. If the definer is not set explicitly,  
a DEFINER clause is added when writing the query into binlog; if 'CURRENT_USER' is 
used as the DEFINER, it is replaced with the value of the current user before 
writing to binlog.

mysql-test/suite/rpl/r/rpl_create_if_not_exists.result:
  Updated the result file after fixing bug#44331
mysql-test/suite/rpl/r/rpl_drop_if_exists.result:
  Updated the result file after fixing bug#44331
mysql-test/suite/rpl/r/rpl_events.result:
  Test result of Bug#44331
mysql-test/suite/rpl/r/rpl_innodb_mixed_dml.result:
  Updated the result file after fixing bug#44331
mysql-test/suite/rpl/t/rpl_events.test:
  Added test to verify if the definer is consistent between master and slave
  when the event is created without the DEFINER clause set explicitly or the
  DEFINER is set to CURRENT_USER
sql/events.cc:
  The "create_query_string" function is added to create a new query string 
  for removing executable comments.
sql/sql_yacc.yy:
  The remember_name token was added for recording the offset of EVENT_SYM.

mysql-test/suite/rpl/r/rpl_create_if_not_exists.result

@@ -29,5 +29,5 @@ t1
 t2
 SHOW EVENTS in mysqltest;
 Db	Name	Definer	Time zone	Type	Execute at	Interval value	Interval field	Starts	Ends	Status	Originator	character_set_client	collation_connection	Database Collation
-mysqltest	e	@	SYSTEM	ONE TIME	#	NULL	NULL	NULL	NULL	SLAVESIDE_DISABLED	1	latin1	latin1_swedish_ci	latin1_swedish_ci
+mysqltest	e	root@localhost	SYSTEM	ONE TIME	#	NULL	NULL	NULL	NULL	SLAVESIDE_DISABLED	1	latin1	latin1_swedish_ci	latin1_swedish_ci
 DROP DATABASE IF EXISTS mysqltest;

mysql-test/suite/rpl/r/rpl_drop_if_exists.result

@@ -43,7 +43,7 @@ master-bin.000001	#	Query	#	#	use `test`; DROP TABLE IF EXISTS db_bug_13684.t
 master-bin.000001	#	Query	#	#	DROP DATABASE IF EXISTS db_bug_13684
 master-bin.000001	#	Query	#	#	CREATE DATABASE db_bug_13684
 master-bin.000001	#	Query	#	#	use `test`; CREATE TABLE db_bug_13684.t (a int)
-master-bin.000001	#	Query	#	#	use `test`; CREATE EVENT db_bug_13684.e
+master-bin.000001	#	Query	#	#	use `test`; CREATE DEFINER=`root`@`localhost` EVENT db_bug_13684.e
 ON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 1 HOUR
 DO
 UPDATE db_bug_13684.t SET a = a + 1
@@ -75,7 +75,7 @@ master-bin.000001	#	Query	#	#	use `test`; DROP TABLE IF EXISTS db_bug_13684.t
 master-bin.000001	#	Query	#	#	DROP DATABASE IF EXISTS db_bug_13684
 master-bin.000001	#	Query	#	#	CREATE DATABASE db_bug_13684
 master-bin.000001	#	Query	#	#	use `test`; CREATE TABLE db_bug_13684.t (a int)
-master-bin.000001	#	Query	#	#	use `test`; CREATE EVENT db_bug_13684.e
+master-bin.000001	#	Query	#	#	use `test`; CREATE DEFINER=`root`@`localhost` EVENT db_bug_13684.e
 ON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 1 HOUR
 DO
 UPDATE db_bug_13684.t SET a = a + 1

mysql-test/suite/rpl/r/rpl_events.result

@@ -191,5 +191,47 @@ select * from t28953;
 END;|
 ALTER EVENT event1 RENAME TO event2;
 DROP EVENT event2;
+CREATE TABLE test.t1(details CHAR(30));
+CREATE EVENT /*!50000 event44331_1 */
+ON SCHEDULE AT CURRENT_TIMESTAMP
+ON COMPLETION PRESERVE DISABLE
+DO INSERT INTO test.t1 VALUES('event event44331_1 fired - no definer');
+CREATE DEFINER=CURRENT_USER /*!50000 EVENT event44331_2 */
+ON SCHEDULE AT CURRENT_TIMESTAMP
+ON COMPLETION PRESERVE DISABLE
+DO INSERT INTO test.t1 VALUES('event event44331_2 fired - DEFINER=CURRENT_USER');
+CREATE DEFINER=CURRENT_USER() EVENT event44331_3
+ON SCHEDULE AT CURRENT_TIMESTAMP
+ON COMPLETION PRESERVE DISABLE
+DO INSERT INTO test.t1 VALUES('event event44331_3 fired - DEFINER=CURRENT_USER() function');
+CREATE /*!50000 DEFINER='user44331' */ EVENT event44331_4
+ON SCHEDULE AT CURRENT_TIMESTAMP
+ON COMPLETION PRESERVE DISABLE
+DO INSERT INTO test.t1 VALUES('event event44331_4 fired - DEFINER=user1');
+Warnings:
+Note	1449	The user specified as a definer ('user44331'@'%') does not exist
+#on master 
+select EVENT_SCHEMA, EVENT_NAME, DEFINER from information_schema.events
+where EVENT_NAME='event44331_1' || EVENT_NAME='event44331_2' || 
+EVENT_NAME='event44331_3' || EVENT_NAME='event44331_4';
+EVENT_SCHEMA	EVENT_NAME	DEFINER
+test	event44331_1	root@localhost
+test	event44331_2	root@localhost
+test	event44331_3	root@localhost
+test	event44331_4	user44331@%
+#on slave
+select EVENT_SCHEMA, EVENT_NAME, DEFINER from information_schema.events
+where EVENT_NAME='event44331_1' || EVENT_NAME='event44331_2' || 
+EVENT_NAME='event44331_3' || EVENT_NAME='event44331_4';
+EVENT_SCHEMA	EVENT_NAME	DEFINER
+test	event44331_1	root@localhost
+test	event44331_2	root@localhost
+test	event44331_3	root@localhost
+test	event44331_4	user44331@%
 SET @@global.event_scheduler= @old_event_scheduler;
 DROP TABLE t28953;
+DROP TABLE t1;
+DROP EVENT event44331_1;
+DROP EVENT event44331_2;
+DROP EVENT event44331_3;
+DROP EVENT event44331_4;

mysql-test/suite/rpl/r/rpl_innodb_mixed_dml.result

@@ -690,7 +690,7 @@ test_rpl	e1	root@localhost	SYSTEM	RECURRING	NULL	1	#	#	NULL	ENABLED	1	latin1	lat
 USE test_rpl;
 SHOW EVENTS;
 Db	Name	Definer	Time zone	Type	Execute at	Interval value	Interval field	Starts	Ends	Status	Originator	character_set_client	collation_connection	Database Collation
-test_rpl	e1	@	SYSTEM	RECURRING	NULL	1	#	#	NULL	SLAVESIDE_DISABLED	1	latin1	latin1_swedish_ci	latin1_swedish_ci
+test_rpl	e1	root@localhost	SYSTEM	RECURRING	NULL	1	#	#	NULL	SLAVESIDE_DISABLED	1	latin1	latin1_swedish_ci	latin1_swedish_ci
 ==========MASTER==========
 SELECT COUNT(*) FROM t1;
 COUNT(*)
@@ -1078,7 +1078,7 @@ master-bin.000001	#	Query	1	#	use `test_rpl`; GRANT EVENT ON *.* TO 'root'@'loca
 master-bin.000001	#	Query	1	#	BEGIN
 master-bin.000001	#	Query	1	#	use `test_rpl`; INSERT INTO t1 VALUES(1, 'test1')
 master-bin.000001	#	Xid	1	#	#
-master-bin.000001	#	Query	1	#	use `test_rpl`; CREATE EVENT e1 ON SCHEDULE EVERY '1' SECOND COMMENT 'e_second_comment' DO DELETE FROM t1
+master-bin.000001	#	Query	1	#	use `test_rpl`; CREATE DEFINER=`root`@`localhost` EVENT e1 ON SCHEDULE EVERY '1' SECOND COMMENT 'e_second_comment' DO DELETE FROM t1
 master-bin.000001	#	Query	1	#	use `test_rpl`; ALTER EVENT e1 RENAME TO e2
 master-bin.000001	#	Query	1	#	use `test_rpl`; DROP EVENT e2
 master-bin.000001	#	Query	1	#	BEGIN

mysql-test/suite/rpl/t/rpl_events.test

@@ -46,12 +46,52 @@ connection master;
 
 DROP EVENT event2;
 
-sync_slave_with_master;
+#
+# BUG#44331
+# This test verifies if the definer is consistent between master and slave,
+# when the event is created without the DEFINER clause set explicitly or the 
+# DEFINER is set to CURRENT_USER
+#
+CREATE TABLE test.t1(details CHAR(30));
+
+CREATE EVENT /*!50000 event44331_1 */
+  ON SCHEDULE AT CURRENT_TIMESTAMP
+  ON COMPLETION PRESERVE DISABLE
+  DO INSERT INTO test.t1 VALUES('event event44331_1 fired - no definer');
+
+CREATE DEFINER=CURRENT_USER /*!50000 EVENT event44331_2 */
+  ON SCHEDULE AT CURRENT_TIMESTAMP
+  ON COMPLETION PRESERVE DISABLE
+  DO INSERT INTO test.t1 VALUES('event event44331_2 fired - DEFINER=CURRENT_USER');
+            
+CREATE DEFINER=CURRENT_USER() EVENT event44331_3
+  ON SCHEDULE AT CURRENT_TIMESTAMP
+  ON COMPLETION PRESERVE DISABLE
+  DO INSERT INTO test.t1 VALUES('event event44331_3 fired - DEFINER=CURRENT_USER() function');
+
+CREATE /*!50000 DEFINER='user44331' */ EVENT event44331_4
+  ON SCHEDULE AT CURRENT_TIMESTAMP
+  ON COMPLETION PRESERVE DISABLE
+  DO INSERT INTO test.t1 VALUES('event event44331_4 fired - DEFINER=user1');
+
+--echo #on master 
+select EVENT_SCHEMA, EVENT_NAME, DEFINER from information_schema.events
+  where EVENT_NAME='event44331_1' || EVENT_NAME='event44331_2' || 
+        EVENT_NAME='event44331_3' || EVENT_NAME='event44331_4';
 
-# Doing cleanup of the table referred to in the event to guarantee
-# that there is no bad timing cauing it to try to access the table.
+sync_slave_with_master;
+connection slave;
+--echo #on slave
+select EVENT_SCHEMA, EVENT_NAME, DEFINER from information_schema.events
+  where EVENT_NAME='event44331_1' || EVENT_NAME='event44331_2' || 
+        EVENT_NAME='event44331_3' || EVENT_NAME='event44331_4';
 
 connection master;
 SET @@global.event_scheduler= @old_event_scheduler;
 DROP TABLE t28953;
+DROP TABLE t1;
+DROP EVENT event44331_1;
+DROP EVENT event44331_2;
+DROP EVENT event44331_3;
+DROP EVENT event44331_4;
 sync_slave_with_master;

sql/events.cc

@@ -341,6 +341,33 @@ common_1_lev_code:
 }
 
 
+/**
+  Create a new query string for removing executable comments 
+  for avoiding leak and keeping consistency of the execution 
+  on master and slave.
+  
+  @param[in] thd                 Thread handler
+  @param[in] buf                 Query string
+
+  @return
+             0           ok
+             1           error
+*/
+static int
+create_query_string(THD *thd, String *buf)
+{
+  /* Append the "CREATE" part of the query */
+  if (buf->append(STRING_WITH_LEN("CREATE ")))
+    return 1;
+  /* Append definer */
+  append_definer(thd, buf, &(thd->lex->definer->user), &(thd->lex->definer->host));
+  /* Append the left part of thd->query after "DEFINER" part */
+  if (buf->append(thd->lex->stmt_definition_begin))
+    return 1;
+ 
+  return 0;
+}
+
 /**
   Create a new event.
 
@@ -439,7 +466,16 @@ Events::create_event(THD *thd, Event_parse_data *parse_data,
     {
       /* Binlog the create event. */
       DBUG_ASSERT(thd->query && thd->query_length);
-      write_bin_log(thd, TRUE, thd->query, thd->query_length);
+      String log_query;
+      if (create_query_string(thd, &log_query))
+      {
+        sql_print_error("Event Error: An error occurred while creating query string, "
+                        "before writing it into binary log.");
+        DBUG_RETURN(TRUE);
+      }
+      /* If the definer is not set or set to CURRENT_USER, the value of CURRENT_USER 
+         will be written into the binary log as the definer for the SQL thread. */
+      write_bin_log(thd, TRUE, log_query.c_ptr(), log_query.length());
     }
   }
   pthread_mutex_unlock(&LOCK_event_metadata);

sql/sql_yacc.yy

@@ -1809,15 +1809,16 @@ server_option:
         ;
 
 event_tail:
-          EVENT_SYM opt_if_not_exists sp_name
+          remember_name EVENT_SYM opt_if_not_exists sp_name
           {
             THD *thd= YYTHD;
             LEX *lex=Lex;
 
-            lex->create_info.options= $2;
+            lex->stmt_definition_begin= $1;
+            lex->create_info.options= $3;
             if (!(lex->event_parse_data= Event_parse_data::new_instance(thd)))
               MYSQL_YYABORT;
-            lex->event_parse_data->identifier= $3;
+            lex->event_parse_data->identifier= $4;
             lex->event_parse_data->on_completion=
                                   Event_parse_data::ON_COMPLETION_DROP;