Fix get null object bug.

object/application.go

@@ -83,6 +83,10 @@ func extendApplicationWithOrg(application *Application) {
 }
 
 func getApplication(owner string, name string) *Application {
+	if owner == "" || name == "" {
+		return nil
+	}
+
 	application := Application{Owner: owner, Name: name}
 	existed, err := adapter.Engine.Get(&application)
 	if err != nil {

object/organization.go

@@ -44,6 +44,10 @@ func GetOrganizations(owner string) []*Organization {
 }
 
 func getOrganization(owner string, name string) *Organization {
+	if owner == "" || name == "" {
+		return nil
+	}
+
 	organization := Organization{Owner: owner, Name: name}
 	existed, err := adapter.Engine.Get(&organization)
 	if err != nil {

object/provider.go

@@ -67,6 +67,10 @@ func GetProviders(owner string) []*Provider {
 }
 
 func getProvider(owner string, name string) *Provider {
+	if owner == "" || name == "" {
+		return nil
+	}
+
 	provider := Provider{Owner: owner, Name: name}
 	existed, err := adapter.Engine.Get(&provider)
 	if err != nil {

object/token.go

@@ -60,6 +60,10 @@ func GetTokens(owner string) []*Token {
 }
 
 func getToken(owner string, name string) *Token {
+	if owner == "" || name == "" {
+		return nil
+	}
+
 	token := Token{Owner: owner, Name: name}
 	existed, err := adapter.Engine.Get(&token)
 	if err != nil {

object/user.go

@@ -78,6 +78,10 @@ func GetUsers(owner string) []*User {
 }
 
 func getUser(owner string, name string) *User {
+	if owner == "" || name == "" {
+		return nil
+	}
+
 	user := User{Owner: owner, Name: name}
 	existed, err := adapter.Engine.Get(&user)
 	if err != nil {