refactor(go): make realtime totals opt in

go/vehicle-gateway/internal/realtime/mysql_query.go

@@ -16,11 +16,12 @@ type mysqlQueryer interface {
 }
 
 type RealtimeTableQuery struct {
-	Protocol string
-	VIN      string
-	Plate    string
-	Limit    int
-	Offset   int
+	Protocol     string
+	VIN          string
+	Plate        string
+	IncludeTotal bool
+	Limit        int
+	Offset       int
 }
 
 type SnapshotRow struct {
@@ -191,16 +192,22 @@ func (h *SnapshotQueryHandler) ServeHTTP(w http.ResponseWriter, r *http.Request)
 		writeError(w, http.StatusBadRequest, err.Error())
 		return
 	}
-	total, err := h.repository.Count(r.Context(), query)
-	if err != nil {
-		writeError(w, http.StatusInternalServerError, err.Error())
-		return
+	var total int64
+	if query.IncludeTotal {
+		total, err = h.repository.Count(r.Context(), query)
+		if err != nil {
+			writeError(w, http.StatusInternalServerError, err.Error())
+			return
+		}
 	}
 	rows, err := h.repository.Query(r.Context(), query)
 	if err != nil {
 		writeError(w, http.StatusInternalServerError, err.Error())
 		return
 	}
+	if !query.IncludeTotal {
+		total = int64(len(rows))
+	}
 	writePage(w, rows, total, query)
 }
 
@@ -229,16 +236,22 @@ func (h *LocationQueryHandler) ServeHTTP(w http.ResponseWriter, r *http.Request)
 		writeError(w, http.StatusBadRequest, err.Error())
 		return
 	}
-	total, err := h.repository.Count(r.Context(), query)
-	if err != nil {
-		writeError(w, http.StatusInternalServerError, err.Error())
-		return
+	var total int64
+	if query.IncludeTotal {
+		total, err = h.repository.Count(r.Context(), query)
+		if err != nil {
+			writeError(w, http.StatusInternalServerError, err.Error())
+			return
+		}
 	}
 	rows, err := h.repository.Query(r.Context(), query)
 	if err != nil {
 		writeError(w, http.StatusInternalServerError, err.Error())
 		return
 	}
+	if !query.IncludeTotal {
+		total = int64(len(rows))
+	}
 	writePage(w, rows, total, query)
 }
 
@@ -253,11 +266,12 @@ func parseRealtimeTableQuery(r *http.Request) (RealtimeTableQuery, error) {
 		return RealtimeTableQuery{}, err
 	}
 	return normalizeRealtimeTableQuery(RealtimeTableQuery{
-		Protocol: values.Get("protocol"),
-		VIN:      values.Get("vin"),
-		Plate:    values.Get("plate"),
-		Limit:    limit,
-		Offset:   offset,
+		Protocol:     values.Get("protocol"),
+		VIN:          values.Get("vin"),
+		Plate:        values.Get("plate"),
+		IncludeTotal: strings.EqualFold(strings.TrimSpace(values.Get("includeTotal")), "true"),
+		Limit:        limit,
+		Offset:       offset,
 	}), nil
 }