add ParamToInt method

service_a/internal/domains/handlers.go

@@ -3,6 +3,7 @@ package domains
 import (
 	"encoding/json"
 	"net/http"
+	"strconv"
 )
 
 type (
@@ -14,3 +15,22 @@ func (bh *BaseHandler) ToJSON(w http.ResponseWriter, statusCode int, data any) {
 	w.WriteHeader(statusCode)
 	json.NewEncoder(w).Encode(data)
 }
+
+func (bh *BaseHandler) ParamToInt(param string, defaultValue ...int) int {
+	if param == "" {
+		if len(defaultValue) > 0 {
+			return defaultValue[0]
+		}
+		return 0
+	}
+
+	value, err := strconv.Atoi(param)
+	if err != nil {
+		if len(defaultValue) > 0 {
+			return defaultValue[0]
+		}
+		return 0
+	}
+
+	return value
+}