feat(api): improve error handling in API requests for clearer messages

Author: PramithaMJ

apps/management-ui/lib/api/bookings.ts

@@ -20,7 +20,11 @@ async function bookingRequest<T>(
   if (!res.ok) {
     let errBody: unknown;
     try { errBody = await res.json(); } catch { /* ignore */ }
-    throw new ApiError(res.status, `${res.status} ${res.statusText}`, errBody);
+    const msg =
+      errBody && typeof errBody === "object" && "error" in errBody
+        ? String((errBody as { error: string }).error)
+        : `${res.status} ${res.statusText}`;
+    throw new ApiError(res.status, msg, errBody);
   }
   if (res.status === 204) return undefined as T;
   return res.json() as Promise<T>;

apps/management-ui/lib/api/client.ts

@@ -38,7 +38,11 @@ async function request<T>(path: string, opts: RequestOptions = {}): Promise<T> {
   if (!res.ok) {
     let errBody: unknown;
     try { errBody = await res.json(); } catch { /* ignore */ }
-    throw new ApiError(res.status, `${res.status} ${res.statusText}`, errBody);
+    const msg =
+      errBody && typeof errBody === "object" && "error" in errBody
+        ? String((errBody as { error: string }).error)
+        : `${res.status} ${res.statusText}`;
+    throw new ApiError(res.status, msg, errBody);
   }
 
   if (res.status === 204) return undefined as T;

apps/management-ui/lib/api/config.ts

@@ -20,7 +20,11 @@ async function configRequest<T>(
   if (!res.ok) {
     let errBody: unknown;
     try { errBody = await res.json(); } catch { /* ignore */ }
-    throw new ApiError(res.status, `${res.status} ${res.statusText}`, errBody);
+    const msg =
+      errBody && typeof errBody === "object" && "error" in errBody
+        ? String((errBody as { error: string }).error)
+        : `${res.status} ${res.statusText}`;
+    throw new ApiError(res.status, msg, errBody);
   }
   if (res.status === 204) return undefined as T;
   return res.json() as Promise<T>;

services/booking-service/internal/handler/handler.go

@@ -141,11 +141,11 @@ func (h *Handler) CreateBooking(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	// ── Policy: slot duration must be a positive multiple of slotDurationMinutes
+	// ── Policy: slot must meet the minimum configured duration ─────────────────
 	slotMinutes := int(req.SlotEnd.Sub(req.SlotStart).Minutes())
-	if bookCfg.SlotDurationMinutes > 0 && slotMinutes%bookCfg.SlotDurationMinutes != 0 {
+	if bookCfg.SlotDurationMinutes > 0 && slotMinutes < bookCfg.SlotDurationMinutes {
 		respondError(w, http.StatusUnprocessableEntity, fmt.Sprintf(
-			"slot duration (%d min) must be a multiple of the configured slot duration (%d min)",
+			"slot duration (%d min) is shorter than the minimum slot duration configured for this tenant (%d min)",
 			slotMinutes, bookCfg.SlotDurationMinutes,
 		))
 		return