private bool _TryGetFromCache(string cacheKey, out GetDriveItemsResponse cachedResponse)
{
var entry = _itemsCache.FirstOrDefault(i => i.Key == cacheKey);
bool found = false;
if (entry != null)
{
if ((DateTime.Now - entry.Created).TotalSeconds > MaxCacheAgeSeconds)
{
_itemsCache.Remove(entry);
cachedResponse = default;
}
else
{
entry.LastUsed = DateTime.Now;
cachedResponse = entry.Value;
found = true;
}
}
else
{
cachedResponse = default;
}
return(found);
}
public async Task <GetDriveItemsResponse> GetDriveItemsAsync(GetDriveItemsRequest request)
{
if (_TryGetFromCache(request.GetCacheKey(), out GetDriveItemsResponse cachedResponse))
{
return(cachedResponse);
}
else
{
if (_TryGetRequestUrlWithPaging(request, out string requestUrl))
{
(bool tokenSuccess, string token) = await _TryGetTokenAsync();
if (tokenSuccess)
{
_http.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", token);
string responseStr = await _http.GetStringAsync(requestUrl);
var graphResponse = SimpleJson.SimpleJson.DeserializeObject <GraphResponse <DriveItem[]> >(responseStr, new SimpleJson.DataContractJsonSerializerStrategy());
var response = new GetDriveItemsResponse(graphResponse.Value, _GetSkipToken(graphResponse.NextLink));
_AddToCache(request, response);
return(response);
}
}
return(null);
}
}
private void _AddToCache(GetDriveItemsRequest request, GetDriveItemsResponse response)
{
if (!_TryGetFromCache(request.GetCacheKey(), out GetDriveItemsResponse cachedResponse))
{
if (_itemsCache.Count > CacheLimit)
{
var prune = _itemsCache.OrderBy(c => c.LastUsed).First();
_itemsCache.Remove(prune);
}
_itemsCache.AddFirst(new LRUCacheEntry <GetDriveItemsResponse>()
{
Key = request.GetCacheKey(),
Value = response,
LastUsed = DateTime.Now,
Created = DateTime.Now
});
}
}
