fix mysql output close panic (#244)

recall704 · ming535 · commit 989fa5458b67 · 2019-12-11T14:49:01.000+08:00
diff --git a/pkg/outputs/mysql/mysql.go b/pkg/outputs/mysql/mysql.go
@@ -139,8 +139,12 @@ func (output *MySQLOutput) Start() error {
 }
 
 func (output *MySQLOutput) Close() {
-	output.db.Close()
-	output.targetSchemaStore.Close()
+	if output.db != nil {
+		output.db.Close()
+	}
+	if output.targetSchemaStore != nil {
+		output.targetSchemaStore.Close()
+	}
 }
 
 func (output *MySQLOutput) GetRouter() core.Router {

Original file line number	Diff line number	Diff line change
`@@ -139,8 +139,12 @@ func (output *MySQLOutput) Start() error {`
`139`	`139`	`}`
`140`	`140`
`141`	`141`	`func (output *MySQLOutput) Close() {`
`142`		`- output.db.Close()`
`143`		`- output.targetSchemaStore.Close()`
	`142`	`+ if output.db != nil {`
	`143`	`+ output.db.Close()`
	`144`	`+ }`
	`145`	`+ if output.targetSchemaStore != nil {`
	`146`	`+ output.targetSchemaStore.Close()`
	`147`	`+ }`
`144`	`148`	`}`
`145`	`149`
`146`	`150`	`func (output *MySQLOutput) GetRouter() core.Router {`