Do optimistic updates work with resource creation and infinite queries?

[brandonhall]

I've got optimistic updates working well for updating or deleting resources within an infinite list. I also have optimistic updates working for updating a single item. What I can't get to work, are optimistic responses for new resources which are added to infinite lists.

I've confirmed the data is correct and onMutate is called prior to the XHR call. Also, after the XHR call completes the list is updated. It's like the optimistic update is delayed until the server responds.

I've dug through some of the React Query source code but haven't found my problem yet. Any ideas?

Here's my onMutate function for one mutation. I have a similar code pattern which is also failing for resource creation.

    onMutate: async mutationArgs => {
      await queryClient.cancelQueries(queryKey);

      const newNotification: ManualNotificationsItemFragment = {
        id: '-1',
        email_count: 0,
        user_count: 0,
        created_at: 0,
        segments: [],
        send_at: null,
        ...mutationArgs.data,
      };

      const baseState = queryClient.getQueryData<QueryData>(queryKey);
      const nextState: QueryData['pages'] = baseState.pages.map((page, index) => {
        if (index !== 0) {
          return page;
        }
        return {
          getManualNotificationItems: {
            ...page.getManualNotificationItems,
            count: page.getManualNotificationItems.count + 1,
            items: [newNotification].concat(page.getManualNotificationItems.items),
          },
        };
      });

      if (baseState) {
        queryClient.setQueryData<QueryData>(queryKey, {
          ...baseState,
          pages: nextState,
        });
      }

      return { baseState };
    },

[brandonhall]

I found the problem. The queries were using notifyOnChangeProps and it was set to isFetching from early testing. As a result, the queries weren't notified of changes to the underlying data. I'm in the middle of a huge migration from Apollo and appreciate the flexibility of this library. Thanks for all the great work.