diff --git a/engine/balance_filter_test.go b/engine/balance_filter_test.go
index 127f26925..deec2625b 100644
--- a/engine/balance_filter_test.go
+++ b/engine/balance_filter_test.go
@@ -618,3 +618,33 @@ func TestBalanceFilterGetFactors(t *testing.T) {
 		}
 	})
 }
+
+func TestBalanceFilterString(t *testing.T) {
+	uuid := "1234-uuid"
+	id := "5678-id"
+	bfType := "type"
+	weight := 10.5
+	disabled := true
+	blocker := false
+
+	factors := ValueFactors{
+		"factor1": 1.5,
+		"factor2": 2.5,
+	}
+	balanceFilter := &BalanceFilter{
+		Uuid:     &uuid,
+		ID:       &id,
+		Type:     &bfType,
+		Weight:   &weight,
+		Disabled: &disabled,
+		Blocker:  &blocker,
+		Factors:  &factors,
+	}
+	expectedJSON := `{"Uuid":"1234-uuid","ID":"5678-id","Type":"type","Value":null,"ExpirationDate":null,"Weight":10.5,"DestinationIDs":null,"RatingSubject":null,"Categories":null,"SharedGroups":null,"TimingIDs":null,"Timings":null,"Disabled":true,"Factors":{"factor1":1.5,"factor2":2.5},"Blocker":false}`
+
+	result := balanceFilter.String()
+
+	if result != expectedJSON {
+		t.Errorf("Expected JSON: %s, but got: %s", expectedJSON, result)
+	}
+}
diff --git a/engine/libstats_test.go b/engine/libstats_test.go
index 506d6dc50..f9fe14906 100644
--- a/engine/libstats_test.go
+++ b/engine/libstats_test.go
@@ -1432,3 +1432,33 @@ func TestRoutesSortedRoutesListAsNavigableMap(t *testing.T) {
 		}
 	}
 }
+
+func TestSortWeight(t *testing.T) {
+	routes := []*SortedRoute{
+		{
+			RouteID:        "route1",
+			SortingData:    map[string]any{"Weight": 10.5},
+			sortingDataF64: map[string]float64{"Weight": 10.5},
+		},
+		{
+			RouteID:        "route2",
+			SortingData:    map[string]any{"Weight": 20.3},
+			sortingDataF64: map[string]float64{"Weight": 20.3},
+		},
+		{
+			RouteID:        "route3",
+			SortingData:    map[string]any{"Weight": 15.7},
+			sortingDataF64: map[string]float64{"Weight": 15.7},
+		},
+	}
+
+	sortedRoutes := &SortedRoutes{
+		Routes: routes,
+	}
+
+	sortedRoutes.SortWeight()
+
+	if sortedRoutes.Routes[0].RouteID != "route2" || sortedRoutes.Routes[1].RouteID != "route3" || sortedRoutes.Routes[2].RouteID != "route1" {
+		t.Errorf("Expected sorted routes to be route2, route3, route1, but got %v", sortedRoutes.Routes)
+	}
+}
diff --git a/engine/storage_csv_test.go b/engine/storage_csv_test.go
index cd7512872..ce5b71d4f 100644
--- a/engine/storage_csv_test.go
+++ b/engine/storage_csv_test.go
@@ -20,6 +20,7 @@ package engine
 
 import (
 	"encoding/csv"
+	"encoding/json"
 	"net/http"
 	"net/http/httptest"
 	"os"
@@ -410,3 +411,87 @@ func TestNewURLCSVStorage(t *testing.T) {
 	}
 
 }
+
+func TestNewGoogleCSVStorageInvalidSpreadsheetID(t *testing.T) {
+	sep := ','
+	spreadsheetID := "invalid-id"
+	storage, err := NewGoogleCSVStorage(sep, spreadsheetID)
+	if err == nil {
+		t.Error("Expected error, but got nil")
+	}
+	if storage != nil {
+		t.Error("Expected nil storage, but got a non-nil value")
+	}
+}
+
+func TestGetAllFoldersInvalidPath(t *testing.T) {
+	nonExistentPath := "/non/existent/path"
+	paths, err := getAllFolders(nonExistentPath)
+	if err == nil {
+		t.Error("Expected error, but got nil")
+	}
+	if len(paths) != 0 {
+		t.Errorf("Expected no paths, but got: %v", paths)
+	}
+}
+
+func TestJoinURLValidBaseURL(t *testing.T) {
+	baseURL := "https://cgrates.com/path"
+	fn := "subpath"
+	expected := "https://cgrates.com/path/subpath"
+	result := joinURL(baseURL, fn)
+	if result != expected {
+		t.Errorf("Expected %s, but got %s", expected, result)
+	}
+}
+
+func TestGetCfgJSONData(t *testing.T) {
+	t.Run("Empty raw JSON", func(t *testing.T) {
+		raw := json.RawMessage{}
+		data, err := getCfgJSONData(raw)
+		if err != nil {
+			t.Errorf("Expected no error, but got: %v", err)
+		}
+		if len(data) != 0 {
+			t.Errorf("Expected no data, but got: %v", data)
+		}
+	})
+	t.Run("Valid raw JSON", func(t *testing.T) {
+		raw := json.RawMessage(`{"key": "value"}`)
+		data, err := getCfgJSONData(raw)
+		if err != nil {
+			t.Errorf("Expected no error, but got: %v", err)
+		}
+		if string(data) != string(raw) {
+			t.Errorf("Expected data %s, but got %s", string(raw), string(data))
+		}
+	})
+	t.Run("Valid file path", func(t *testing.T) {
+		path := "/tmp/mockConfigPath.json"
+		expectedContent := []byte(`{"key": "value"}`)
+		err := os.WriteFile(path, expectedContent, 0600)
+		if err != nil {
+			t.Fatalf("Failed to create mock file: %v", err)
+		}
+		defer os.Remove(path)
+		raw := json.RawMessage(`"` + path + `"`)
+		data, err := getCfgJSONData(raw)
+		if err != nil {
+			t.Errorf("Expected no error, but got: %v", err)
+		}
+		if string(data) != string(expectedContent) {
+			t.Errorf("Expected data %s, but got %s", string(expectedContent), string(data))
+		}
+	})
+
+	t.Run("Invalid file path", func(t *testing.T) {
+		raw := json.RawMessage(`"/nonexistent/path/to/file.json"`)
+		data, err := getCfgJSONData(raw)
+		if err == nil {
+			t.Errorf("Expected error, but got none")
+		}
+		if data != nil {
+			t.Errorf("Expected no data, but got: %v", data)
+		}
+	})
+}