MDEV-20511: Galera replication of events is not consistent

After SST from master node (the one where event is ENABLED) - you will end up with the event enabled on two nodes, hence it's now being executed twice. It can be solved by comparing event's originator with server_id. if not equal, then change its status to 'SLAVESIDE_DISABLED'

Changes to be committed:
	new file:   mysql-test/suite/galera/r/galera_events2.result
	new file:   mysql-test/suite/galera/t/galera_events2.test
	modified:   sql/events.cc

mysql-test/suite/galera/r/galera_events2.result

@@ -0,0 +1,122 @@
+connection node_1;
+connection node_2;
+connection node_1;
+CREATE TABLE event_table(a int) engine=innodb;
+CREATE EVENT event_2 ON SCHEDULE EVERY 1 SECOND
+ENDS NOW() + INTERVAL 6 SECOND
+ON COMPLETION NOT PRESERVE
+DO
+INSERT INTO event_table VALUES (1);
+Warnings:
+Warning	1105	Event scheduler is switched off, use SET GLOBAL event_scheduler=ON to enable it.
+# node_1 event should be there
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='event_2';
+EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
+def	test	event_2	root@localhost	SQL	INSERT INTO event_table VALUES (1)	RECURRING	NULL	1	SECOND	ENABLED	NOT PRESERVE	
+connection node_2;
+# node_2 event should be there
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='event_2';
+EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
+def	test	event_2	root@localhost	SQL	INSERT INTO event_table VALUES (1)	RECURRING	NULL	1	SECOND	SLAVESIDE_DISABLED	NOT PRESERVE	
+connection node_1;
+SET GLOBAL event_scheduler=ON;
+SHOW VARIABLES LIKE 'event_scheduler';
+Variable_name	Value
+event_scheduler	ON
+# node_1 event should be removed
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='event_2';
+EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
+connection node_2;
+# node_2 event should be removed
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='event_2';
+EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
+connection node_1;
+SET GLOBAL event_scheduler=OFF;
+DROP TABLE event_table;
+connection node_1;
+CREATE DATABASE IF NOT EXISTS events_test;
+use events_test;
+CREATE USER ev_test@localhost;
+GRANT ALL ON events_test.* to ev_test@localhost;
+connect  ev_con1,localhost,ev_test,,events_test;
+CREATE EVENT one_event ON SCHEDULE EVERY 10 SECOND DO SELECT 123;
+Warnings:
+Warning	1105	Event scheduler is switched off, use SET GLOBAL event_scheduler=ON to enable it.
+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
+events_test	one_event	ev_test@localhost	SYSTEM	RECURRING	NULL	10	#	#	NULL	ENABLED	1	latin1	latin1_swedish_ci	latin1_swedish_ci
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS ORDER BY EVENT_SCHEMA, EVENT_NAME;
+EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
+def	events_test	one_event	ev_test@localhost	SQL	SELECT 123	RECURRING	NULL	10	SECOND	ENABLED	NOT PRESERVE	
+ALTER EVENT one_event ON SCHEDULE EVERY 10 SECOND;
+"The definer should be ev_test@localhost"
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
+def	events_test	one_event	ev_test@localhost	SQL	SELECT 123	RECURRING	NULL	10	SECOND	ENABLED	NOT PRESERVE	
+connection node_2;
+use events_test;
+"The definer should be ev_test@localhost"
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
+def	events_test	one_event	ev_test@localhost	SQL	SELECT 123	RECURRING	NULL	10	SECOND	SLAVESIDE_DISABLED	NOT PRESERVE	
+connection node_1;
+disconnect ev_con1;
+use test;
+DROP EVENT events_test.one_event;
+DROP USER ev_test@localhost;
+DROP DATABASE events_test;
+connection node_1;
+use test;
+CREATE EVENT one_event ON SCHEDULE EVERY 10 SECOND DO SELECT 123;
+Warnings:
+Warning	1105	Event scheduler is switched off, use SET GLOBAL event_scheduler=ON to enable it.
+# node_1 Event should be enabled
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
+def	test	one_event	root@localhost	SQL	SELECT 123	RECURRING	NULL	10	SECOND	ENABLED	NOT PRESERVE	
+connection node_2;
+use test;
+# node_2 Event should be SERVERSIDE_DISABLED
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
+def	test	one_event	root@localhost	SQL	SELECT 123	RECURRING	NULL	10	SECOND	SLAVESIDE_DISABLED	NOT PRESERVE	
+CREATE TABLE t1 (f1 INTEGER PRIMARY KEY, f2 CHAR(1)) engine=InnoDB;
+INSERT INTO t1 VALUES (1, 'a'), (2, 'a'), (3, 'a');
+SELECT * FROM t1;
+f1	f2
+1	a
+2	a
+3	a
+Shutting down server ...
+connection node_1;
+UPDATE t1 SET f2 = 'b' WHERE f1 > 1;
+UPDATE t1 SET f2 = 'c' WHERE f1 > 2;
+SELECT * FROM t1;
+f1	f2
+1	a
+2	b
+3	c
+connection node_2;
+# Force SST from node_1 to node_2
+Starting server ...
+SELECT * FROM t1;
+f1	f2
+1	a
+2	b
+3	c
+# node_2 Event should be SERVERSIDE_DISABLED
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
+def	test	one_event	root@localhost	SQL	SELECT 123	RECURRING	NULL	10	SECOND	SLAVESIDE_DISABLED	NOT PRESERVE	
+connection node_1;
+SELECT * FROM t1;
+f1	f2
+1	a
+2	b
+3	c
+# node_1 Event should be ENABLED
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
+def	test	one_event	root@localhost	SQL	SELECT 123	RECURRING	NULL	10	SECOND	ENABLED	NOT PRESERVE	
+DROP TABLE t1;
+DROP EVENT one_event;

mysql-test/suite/galera/t/galera_events2.test

@@ -0,0 +1,144 @@
+--source include/galera_cluster.inc
+
+# Save original auto_increment_offset values.
+--let $node_1=node_1
+--let $node_2=node_2
+--source include/auto_increment_offset_save.inc
+
+#
+# Test case 1: "ONE TIME" events should be dropped on slave nodes after expiring on master (event creator node)
+#
+
+--connection node_1
+
+CREATE TABLE event_table(a int) engine=innodb;
+
+CREATE EVENT event_2 ON SCHEDULE EVERY 1 SECOND
+ENDS NOW() + INTERVAL 6 SECOND
+ON COMPLETION NOT PRESERVE
+DO
+  INSERT INTO event_table VALUES (1);
+
+--echo # node_1 event should be there
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='event_2';
+
+--connection node_2
+--echo # node_2 event should be there
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='event_2';
+
+--connection node_1
+SET GLOBAL event_scheduler=ON;
+SHOW VARIABLES LIKE 'event_scheduler';
+
+# Let event_2 reach the end of its execution interval
+let $wait_condition=select count(*) = 0 from information_schema.events where event_name='event_2';
+--source include/wait_condition.inc
+
+--echo # node_1 event should be removed
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='event_2';
+
+--connection node_2
+--echo # node_2 event should be removed
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='event_2';
+
+--connection node_1
+SET GLOBAL event_scheduler=OFF;
+DROP TABLE event_table;
+
+#
+# Test case 2: After doing ALTER EVENT, slave nodes should have same definer as master
+#
+
+--connection node_1
+
+CREATE DATABASE IF NOT EXISTS events_test;
+use events_test;
+CREATE USER ev_test@localhost;
+GRANT ALL ON events_test.* to ev_test@localhost;
+connect (ev_con1,localhost,ev_test,,events_test);
+
+CREATE EVENT one_event ON SCHEDULE EVERY 10 SECOND DO SELECT 123;
+--replace_column 8 # 9 #
+SHOW EVENTS;
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS ORDER BY EVENT_SCHEMA, EVENT_NAME;
+ALTER EVENT one_event ON SCHEDULE EVERY 10 SECOND;
+--echo "The definer should be ev_test@localhost"
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+
+--connection node_2
+use events_test;
+--echo "The definer should be ev_test@localhost"
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+
+--connection node_1
+--disconnect ev_con1
+use test;
+DROP EVENT events_test.one_event;
+DROP USER ev_test@localhost;
+DROP DATABASE events_test;
+
+#
+# Test case 3: After SST from master node (the one where event is ENABLED) , slave event status should be 'SLAVESIDE_DISABLED'
+#
+
+--connection node_1
+use test;
+CREATE EVENT one_event ON SCHEDULE EVERY 10 SECOND DO SELECT 123;
+
+--echo # node_1 Event should be enabled
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+
+--connection node_2
+use test;
+--echo # node_2 Event should be SERVERSIDE_DISABLED
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+
+CREATE TABLE t1 (f1 INTEGER PRIMARY KEY, f2 CHAR(1)) engine=InnoDB;
+INSERT INTO t1 VALUES (1, 'a'), (2, 'a'), (3, 'a');
+
+SELECT * FROM t1;
+
+# Initiate normal shutdown on the node 2 and wait until shutdown has been completed:
+
+--echo Shutting down server ...
+--source include/shutdown_mysqld.inc
+
+--connection node_1
+
+--let $wait_condition = SELECT VARIABLE_VALUE = 1 FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'wsrep_cluster_size'
+--source include/wait_condition.inc
+
+UPDATE t1 SET f2 = 'b' WHERE f1 > 1;
+UPDATE t1 SET f2 = 'c' WHERE f1 > 2;
+
+SELECT * FROM t1;
+
+--connection node_2
+
+# Remove the "grastate.dat" file (to initiate new SST) and restart node 2
+
+--remove_file $MYSQLTEST_VARDIR/mysqld.2/data/grastate.dat
+
+--echo # Force SST from node_1 to node_2
+--let $start_mysqld_params=
+--echo Starting server ...
+--source include/start_mysqld.inc
+
+--let $wait_condition = SELECT VARIABLE_VALUE = 2 FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'wsrep_cluster_size'
+--source include/wait_condition.inc
+
+# Sanity check (node 2 is running now and can perform SQL operators):
+
+SELECT * FROM t1;
+--echo # node_2 Event should be SERVERSIDE_DISABLED
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+
+--connection node_1
+SELECT * FROM t1;
+--echo # node_1 Event should be ENABLED
+SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+
+DROP TABLE t1;
+DROP EVENT one_event;
+
+--source include/auto_increment_offset_restore.inc

sql/events.cc

@@ -1198,6 +1198,46 @@ Events::load_events_from_db(THD *thd)
       delete et;
       goto end;
     }
+
+#ifdef WITH_WSREP
+    /**
+      IF SST is done from a galera node that is also acting as MASTER
+      newly synced node in galera eco-system will also copy-over the event state
+      enabling duplicate event in galera eco-system.
+      DISABLE such events if the current node is not event orginator.
+      (Also, make sure you skip disabling it if is already disabled to avoid
+       creation of redundant action)
+      NOTE:
+      This complete system relies on server-id. Ideally server-id should be
+      same for all nodes of galera eco-system but they aren't same.
+      Infact, based on galera use-case it seems like it recommends to have each
+      node with different server-id.
+    */
+    if (et->originator != thd->variables.server_id)
+    {
+        if (et->status == Event_parse_data::SLAVESIDE_DISABLED)
+          continue;
+
+        store_record(table, record[1]);
+        table->field[ET_FIELD_STATUS]->
+                store((longlong) Event_parse_data::SLAVESIDE_DISABLED,
+                      TRUE);
+
+	/* All the dmls to mysql.events tables are stmt bin-logged. */
+        bool save_binlog_row_based;
+        if ((save_binlog_row_based= thd->is_current_stmt_binlog_format_row()))
+	  thd->set_current_stmt_binlog_format_stmt();
+
+        (void) table->file->ha_update_row(table->record[1], table->record[0]);
+
+        if (save_binlog_row_based)
+          thd->set_current_stmt_binlog_format_row();
+
+        delete et;
+        continue;
+    }
+#endif /* WITH_WSREP */
+
     /**
       Since the Event_queue_element object could be deleted inside
       Event_queue::create_event we should save the value of dropped flag