add total amount in home page

pkg/errs/error.go

@@ -27,6 +27,7 @@ const (
 	NormalSubcategoryCategory       = 6
 	NormalSubcategoryTag            = 7
 	NormalSubcategoryDataManagement = 8
+	NormalSubcategoryOverview       = 9
 )
 
 // Error represents the specific error returned to user

pkg/errs/overview.go

@@ -0,0 +1,9 @@
+package errs
+
+import "net/http"
+
+// Error codes related to overview
+var (
+	ErrQueryItemsEmpty   = NewNormalError(NormalSubcategoryOverview, 0, http.StatusBadRequest, "query items cannot be empty")
+	ErrQueryItemsTooMuch = NewNormalError(NormalSubcategoryOverview, 1, http.StatusBadRequest, "query items too much")
+)