public async Task FlushCacheForSiteMutationAsync(HttpRequest request, IUrlHelper url, Guid oid)
{
// The endpoint to get this site is the same as any mutation endpoint so generates the same cache key.
await _cacheService.TryDeleteCacheValueAsync(request, oid); // /api/sites/{siteId}/
// The get all sites endpoint.
var allSitesUrl = url.Action(nameof(SitesController.GetSites), "Sites", null, request.Scheme);
await _cacheService.TryDeleteCacheValueAsync(_cacheService.BuildCacheKeyFromUrl(allSitesUrl, oid)); // /api/sites/
}