Update static/js/common.js

static/js/common.js

@@ -5,9 +5,15 @@ function apiPost(path, body) {
         method: 'POST',
         headers: { 'Content-Type': 'application/json' },
         body: JSON.stringify(body)
-    }).then(res => res.json());
+    }).then(res => {
+        if (!res.ok) {
+            return res.json().then(err => { throw err; });
+        }
+        return res.json();
+    });
 }
 
+
 function apiGet(path) {
     return fetch(`${apiBase}${path}`)
         .then(res => res.json());