fix: avoid runtime panic when the errors field of the response is nil

Signed-off-by: Norbert Biczo <pyrooka@users.noreply.github.com>

Author: pyrooka

core/base_service.go

@@ -627,7 +627,11 @@ func getErrorMessage(responseMap map[string]interface{}, statusCode int) string
 		var errors Errors
 		responseBuffer, _ := json.Marshal(responseMap)
 		if err := json.Unmarshal(responseBuffer, &errors); err == nil {
-			return errors.Errors[0].Message
+			if len(errors.Errors) > 0 {
+				return errors.Errors[0].Message
+			}
+
+			return ""
 		}
 	}
 

core/base_service_test.go

@@ -2170,6 +2170,8 @@ func TestErrorMessage(t *testing.T) {
 	testGetErrorMessage(t, http.StatusInternalServerError,
 		`{"errorMessage":{"statusCode":500,"message":"Internal Server Error"}}`,
 		"Internal Server Error")
+
+	testGetErrorMessage(t, http.StatusInternalServerError, `{"errors": null}`, "")
 }
 
 func getTLSVersion(service *BaseService) int {