correct-apricot

Is `data` always meant to be possibly undefined

Even when using even when using keepPreviousData and placeholderData?

const { data } = useQuery({
  queryKey: taskBoardQueries.weeklyHours({ start }).queryKey,
  queryFn: async () => {
    const response = await taskBoardClient.getWeeklyBillableHours({
      start: start.value,
    });

    const schema = z.object({
      hours: z.number(),
      target: z.number().nullable(),
    });

    return schema.parse(response);
  },
  placeholderData: {
    target: 0,
    hours: 0,
  },
  keepPreviousData: true,
});

const { data } = useQuery({
  queryKey: taskBoardQueries.weeklyHours({ start }).queryKey,
  queryFn: async () => {
    const response = await taskBoardClient.getWeeklyBillableHours({
      start: start.value,
    });

    const schema = z.object({
      hours: z.number(),
      target: z.number().nullable(),
    });

    return schema.parse(response);
  },
  placeholderData: {
    target: 0,
    hours: 0,
  },
  keepPreviousData: true,
});

Should data.value (Vue) be possible undefined in this case? As far as I know, with this set up, it will never not be defined right?

3 Replies

extended-salmon•3y ago

yes, placeholderData is no guarantee that there will always be data. if the query fails, data will be undefined: https://tkdodo.eu/blog/placeholder-and-initial-data-in-react-query

Placeholder and Initial Data in React Query

Learn about the different possibilities to avoid loading spinners in React Query.

correct-apricotOP•3y ago

Ah okay that makes sense. So really there's no way to ensure the data is always defined is there? Just trying to battle best way where I had a dsahboard with heaps of async calls to stats (10+ endpoints) and all that data loads at different times, but if I use some placeholder data, my graphs etc still populate and I don't get all the jumping around Except I still get a litany of TS errors

extended-salmon•3y ago

it is defined if you set initialData

Gaming

Programming

Is `data` always meant to be possibly undefined

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