Removing queries manually from the cache

[sbruinsje]

I have created a utility function to update the query cache based on some patch function. I want this utility function to do the following:

• Get all queries for a given endpoint from the state.
• Iterate over each of them:
  • If the query has an active subscription, the query is updated using a provided patch function.
  • If the query has no active subscription, the query gets removed from the cache entirely.

This function is used when doing optimistic updates: instantly update all active queries with some patch function and purge the inactive queries for that endpoint so they won't be re-used in the future.

However, I haven't found a way to purge cache entries manually from the state. I don't want to invalidate tags because that causes a refetch of all the active queries as well which makes no sense cause we are optimistically updating those already. Is there a way to purge specific queries from the cache? Or do you see a better approach to what I am trying to do?

The utility function is a work in progress but looks something like this:

export function updateQueryCache<R>({
  getState,
  dispatch,
  api,
  endpointName,
  patchFunction,
}: UpdateQueryCacheArgs<R>): PatchResult[] {
  const state = getState();
  const allQueries = Object.entries(state.api.queries);
  const subscriptions = state.api.subscriptions;
  const endpointQueries = allQueries.filter(([key]) => key.startsWith(`${endpointName}(`));

  const patchResults: PatchResult[] = [];

  endpointQueries.forEach(([queryKey, query]) => {
    if (!query) return;

    // Check if this query has active subscriptions
    const hasActiveSubscriptions =
      subscriptions[queryKey] &&
      Object.keys(subscriptions[queryKey] as Record<string, unknown>).length > 0;

    // If The query has an active subscription then we want to update it using the patch function.
    // If the query has NO active subscription then we want to remove it from the cache which is
    // less work then patching it. If the query becomes active again it will be refetched instead of
    // re-used from the cache. This is safeguard against having to update many outdated cache
    // entries which will never be re-used (aka a performance optimization).
    
    if (hasActiveSubscriptions) {
      const patchResult = dispatch(
        api.util.updateQueryData(
          endpointName,
          (query as { originalArgs: unknown }).originalArgs,
          patchFunction,
        ),
      ) as PatchResult;
      patchResults.push(patchResult);
    } else {
      // TODO: how to remove cache entries?
    }
  });