2 Bug fixes.

1. Fix bug introduced in last commit.
Don't try to json encode data that is already encoded.

2. Honor --max-number-client-config
When the creation moved from Clients.svelte to NewClient.svelte the
check in returned json for errors got lost. Now it is back.

server.go

@@ -603,19 +603,14 @@ func (s *Server) CreateClient(w http.ResponseWriter, r *http.Request, ps httprou
 				Error: "Max number of configs: " + strconv.Itoa(*maxNumberClientConfig),
 			}
 
-			j, err := json.Marshal(e)
-			if err != nil {
-				log.Error(err)
-				return
-			}
-
 			w.WriteHeader(http.StatusBadRequest)
-			err = json.NewEncoder(w).Encode(j)
+			err := json.NewEncoder(w).Encode(e)
 			if err != nil {
 				log.Error(err)
 				w.WriteHeader(http.StatusInternalServerError)
 				return
 			}
+			return
 		}
 	}
 

ui/src/NewClient.svelte

@@ -28,11 +28,21 @@
         "Content-Type": "application/json",
       },
       body: JSON.stringify(client),
+    })
+      .then(response => {
+        return response.json();
+    })
+    .then(data => {
+      if (typeof data.Error != "undefined") {
+          console.log(data.Error);
+          alert(data.Error);
+      } else {
+        console.log("New client added", data);
+      }
     });
-    client = await res.json();
-    console.log("New client added", client);
     navigate("/", { replace: true });
-  }
+  };
+
 
   function handleBackClick(event) {
     navigate("/", { replace: true });