change OnDDL to OnTableChanged (go-mysql-org#244)

Author: siddontang

canal/handler.go

@@ -7,6 +7,10 @@ import (
 
 type EventHandler interface {
 OnRotate(roateEvent *replication.RotateEvent) error
+// OnTableChanged is called when the table is created, altered, renamed or dropped.
+// You need to clear the associated data like cache with the table.
+// It will be called before OnDDL.
+OnTableChanged(schema string, table string) error
 OnDDL(nextPos mysql.Position, queryEvent *replication.QueryEvent) error
 OnRow(e *RowsEvent) error
 OnXID(nextPos mysql.Position) error
@@ -19,8 +23,9 @@ type EventHandler interface {
 type DummyEventHandler struct {
 }
 
-func (h *DummyEventHandler) OnRotate(*replication.RotateEvent) error { return nil }
-func (h *DummyEventHandler) OnDDL(mysql.Position, *replication.QueryEvent) error {
+func (h *DummyEventHandler) OnRotate(*replication.RotateEvent) error { return nil }
+func (h *DummyEventHandler) OnTableChanged(schema string, table string) error { return nil }
+func (h *DummyEventHandler) OnDDL(nextPos mysql.Position, queryEvent *replication.QueryEvent) error {
 return nil
 }
 func (h *DummyEventHandler) OnRow(*RowsEvent) error { return nil }

canal/sync.go

@@ -14,7 +14,7 @@ import (
 )
 
 var (
-expCreateTable  = regexp.MustCompile("(?i)^CREATE\\sTABLE(\\sIF\\sNOT\\sEXISTS)?\\s`{0,1}(.*?)`{0,1}\\.{0,1}`{0,1}([^`\\.]+?)`{0,1}\\s.*")
+expCreateTable = regexp.MustCompile("(?i)^CREATE\\sTABLE(\\sIF\\sNOT\\sEXISTS)?\\s`{0,1}(.*?)`{0,1}\\.{0,1}`{0,1}([^`\\.]+?)`{0,1}\\s.*")
 expAlterTable = regexp.MustCompile("(?i)^ALTER\\sTABLE\\s.*?`{0,1}(.*?)`{0,1}\\.{0,1}`{0,1}([^`\\.]+?)`{0,1}\\s.*")
 expRenameTable = regexp.MustCompile("(?i)^RENAME\\sTABLE\\s.*?`{0,1}(.*?)`{0,1}\\.{0,1}`{0,1}([^`\\.]+?)`{0,1}\\s{1,}TO\\s.*?")
 expDropTable = regexp.MustCompile("(?i)^DROP\\sTABLE(\\sIF\\sEXISTS){0,1}\\s`{0,1}(.*?)`{0,1}\\.{0,1}`{0,1}([^`\\.]+?)`{0,1}(?:$|\\s)")
@@ -115,9 +115,9 @@ func (c *Canal) runSyncBinlog() error {
 }
 case *replication.QueryEvent:
 var (
-mb [][]byte
+mb  [][]byte
 schema []byte
-table []byte
+table  []byte
 )
 regexps := []regexp.Regexp{*expCreateTable, *expAlterTable, *expRenameTable, *expDropTable}
 for _, reg := range regexps {
@@ -143,10 +143,14 @@ func (c *Canal) runSyncBinlog() error {
 force = true
 c.ClearTableCache(schema, table)
 log.Infof("table structure changed, clear table cache: %s.%s\n", schema, table)
-if err = c.eventHandler.OnDDL(pos, e); err != nil {
+if err = c.eventHandler.OnTableChanged(string(schema), string(table)); err != nil {
 return errors.Trace(err)
 }
 
+// Now we only handle Table Changed DDL, maybe we will support more later.
+if err = c.eventHandler.OnDDL(pos, e); err != nil {
+return errors.Trace(err)
+}
 default:
 continue
 }

replication/event.go

@@ -453,7 +453,7 @@ func (e *MariadbGTIDEvent) Decode(data []byte) error {
 }
 
 func (e *MariadbGTIDEvent) Dump(w io.Writer) {
-fmt.Fprintf(w, "GTID: %s\n", e.GTID)
+fmt.Fprintf(w, "GTID: %v\n", e.GTID)
 fmt.Fprintln(w)
 }