Added port tag update

Signed-off-by: Zhenfang Wei <kopkop@gmail.com>

examples/example.go

@@ -60,6 +60,13 @@ func main() {
 	if err != nil {
 		fmt.Println(err.Error())
 	}
+	fmt.Printf("Successfully created the veth port %s\n", "vethA")
+
+	err = client.UpdatePortTagByName(brName, "vethA", 10)
+	if err != nil {
+		fmt.Println(err.Error())
+	}
+	fmt.Printf("Successfully updated the veth port %s's tag value to %d\n", "vethA", 10)
 
 	ports, err := client.FindAllPortUUIDsOnBridge(brName)
 	if err != nil {

ovsclient.go

@@ -32,6 +32,7 @@ const (
 	insertOperation = "insert"
 	mutateOperation = "mutate"
 	selectOperation = "select"
+	updateOperation = "update"
 )
 
 // OvsClient is the interface towards outside user
@@ -42,6 +43,8 @@ type OvsClient interface {
 	CreateVethPort(brname, portname string, vlantag int) error
 	CreatePatchPort(brname, portname, peername string) error
 	DeletePort(brname, porname string) error
+	UpdatePortTagByName(brname, portname string, vlantag int) error
+	UpdatePortTagByUUID(portUUID string, vlantag int) error
 	FindAllPortUUIDsOnBridge(brname string) ([]string, error)
 	PortExistsOnBridge(portname, brname string) (bool, error)
 	RemoveInterfaceFromPort(portname, interfaceUUID string) error

ovsport.go

@@ -268,3 +268,61 @@ func (client *ovsClient) getPortUUIDByName(portname string) (string, error) {
 	answer := reply[0].Rows[0]["_uuid"].([]interface{})[1].(string)
 	return answer, nil
 }
+
+func (client *ovsClient) UpdatePortTagByName(brname, portname string, vlantag int) error {
+	if vlantag < 0 || vlantag > 4095 {
+		return fmt.Errorf("The vlan tag value is not in valid range")
+	}
+	portExist, err := client.PortExistsOnBridge(portname, brname)
+	if err != nil {
+		return err
+	}
+	if !portExist {
+		return fmt.Errorf("The port %s doesn't exists on bridge %s", portname, brname)
+	}
+	portUUID, err := client.getPortUUIDByName(portname)
+	if err != nil {
+		return err
+	}
+	return client.UpdatePortTagByUUID(portUUID, vlantag)
+}
+
+func (client *ovsClient) UpdatePortTagByUUID(portUUID string, vlantag int) error {
+	if vlantag < 0 || vlantag > 4095 {
+		return fmt.Errorf("The vlan tag value is not in valid range")
+	}
+	portExist, err := client.portExistsByUUID(portUUID)
+	if err != nil {
+		return err
+	}
+	if !portExist {
+		return fmt.Errorf("The port with UUID %s doesn't exists", portUUID)
+	}
+	updateCondition := libovsdb.NewCondition("_uuid", "==", []string{"uuid", portUUID})
+	// port row to update
+	port := make(map[string]interface{})
+	port["tag"] = vlantag
+
+	updateOp := libovsdb.Operation{
+		Op:    updateOperation,
+		Table: portTableName,
+		Where: []interface{}{updateCondition},
+	}
+
+	// Inserting a Port row in Port table requires mutating the Bridge table
+	mutateUUID := []libovsdb.UUID{libovsdb.UUID{GoUuid: portUUID}}
+	mutateSet, _ := libovsdb.NewOvsSet(mutateUUID)
+	mutation := libovsdb.NewMutation("ports", updateOperation, mutateSet)
+	condition := libovsdb.NewCondition("_uuid", "==", []string{"uuid", portUUID})
+
+	// simple mutate operation
+	mutateOp := libovsdb.Operation{
+		Op:        mutateOperation,
+		Table:     bridgeTableName,
+		Mutations: []interface{}{mutation},
+		Where:     []interface{}{condition},
+	}
+
+	operations := []libovsdb.Operation{updateOp, mutateOp}
+	return client.transact(operations, "update port")
+}