Fix race condition with plugin bundles

There may be a race condition when loading plugin bundles with lazy dependencies:

The OpenAPI plugin depends on "redux" and "react-redux", which are bundled in the lazy "ui-legacy" module, as the usage of redux is deprecated in the scmm. The "ui-legacy" module also binds a global wrapper extension point around the whole app. Due to a bug in the plugin loader, plugin bundles were marked as successfully loaded even if a lazy dependency hadn't successfully loaded yet. This caused the extension point from the "ui-legacy" bundle to be bound after the initial render. As the process of extension point binding  doesn't trigger a re-render, the redux provider was not wrapped around the app on initial load. When the user now moved focus out of and back into the window, react-query hooks automatically refetched e.g. the index links, which caused a re-render. Now with the bound extension point applied. This caused the whole app to be unmounted and re-mounted, which in turn reset all form fields anywhere below in the tree.

Also fixes a bug where the global notifications component was executing a state update while already unmounted.

Also fixes a bug in the user creation form where an object literal was passed to the form's default values which caused a form reset whenever the component re-rendered.

Committed-by: Rene Pfeuffer <rene.pfeuffer@cloudogu.com>

scm-ui/ui-api/src/notifications.ts

@@ -28,6 +28,7 @@ import { Link, Notification, NotificationCollection } from "@scm-manager/ui-type
 import { apiClient } from "./apiclient";
 import { useCallback, useEffect, useState } from "react";
 import { requiredLink } from "./links";
+import { useCancellablePromise } from "./utils";
 
 export const useNotifications = () => {
   const { data: me } = useMe();
@@ -95,22 +96,30 @@ export const useNotificationSubscription = (
   const [notifications, setNotifications] = useState<Notification[]>([]);
   const [disconnectedAt, setDisconnectedAt] = useState<Date>();
   const link = (notificationCollection?._links.subscribe as Link)?.href;
+  const cancelOnUnmount = useCancellablePromise();
 
   const onVisible = useCallback(() => {
     // we don't need to catch the error,
     // because if the refetch throws an error the parent useNotifications should catch it
-    refetch().then((collection) => {
-      if (collection) {
-        const newNotifications = collection._embedded?.notifications.filter((n) => {
-          return disconnectedAt && disconnectedAt < new Date(n.createdAt);
-        });
-        if (newNotifications && newNotifications.length > 0) {
-          setNotifications((previous) => [...previous, ...newNotifications]);
+    cancelOnUnmount(refetch()).then(
+      (collection) => {
+        if (collection) {
+          const newNotifications = collection._embedded?.notifications.filter((n) => {
+            return disconnectedAt && disconnectedAt < new Date(n.createdAt);
+          });
+          if (newNotifications && newNotifications.length > 0) {
+            setNotifications((previous) => [...previous, ...newNotifications]);
+          }
+          setDisconnectedAt(undefined);
+        }
+      },
+      (reason) => {
+        if (!reason.isCanceled) {
+          throw reason;
         }
-        setDisconnectedAt(undefined);
       }
-    });
-  }, [disconnectedAt, refetch]);
+    );
+  }, [cancelOnUnmount, disconnectedAt, refetch]);
 
   const onHide = useCallback(() => {
     setDisconnectedAt(new Date());

scm-ui/ui-api/src/utils.ts

@@ -22,8 +22,44 @@
  * SOFTWARE.
  */
 
+import { useCallback, useEffect, useRef } from "react";
+
 export const createQueryString = (params: Record<string, string>) => {
   return Object.keys(params)
     .map((k) => encodeURIComponent(k) + "=" + encodeURIComponent(params[k]))
     .join("&");
 };
+
+export type CancelablePromise<T> = Promise<T> & { cancel: () => void };
+
+export function makeCancelable<T>(promise: Promise<T>): CancelablePromise<T> {
+  let isCanceled = false;
+  const wrappedPromise = new Promise<T>((resolve, reject) => {
+    promise
+      .then((val) => (isCanceled ? reject({ isCanceled }) : resolve(val)))
+      .catch((error) => (isCanceled ? reject({ isCanceled }) : reject(error)));
+  });
+  return Object.assign(wrappedPromise, {
+    cancel() {
+      isCanceled = true;
+    },
+  });
+}
+
+export function useCancellablePromise() {
+  const promises = useRef<Array<CancelablePromise<unknown>>>();
+
+  useEffect(() => {
+    promises.current = promises.current || [];
+    return function cancel() {
+      promises.current?.forEach((p) => p.cancel());
+      promises.current = [];
+    };
+  }, []);
+
+  return useCallback(<T>(p: Promise<T>) => {
+    const cPromise = makeCancelable(p);
+    promises.current?.push(cPromise);
+    return cPromise;
+  }, []);
+}