/// <summary>
/// Updates a cached request when the item has expired.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="arguments"></param>
public void CacheUpdated <T>(CacheEntryUpdateArguments arguments) where T : new()
{
if (arguments.RemovedReason == CacheEntryRemovedReason.Expired)
{
CachedRequestResponse <T> cachedItem = arguments.Source[arguments.Key] as CachedRequestResponse <T>;
log.DebugFormat("Cache item expired and being updated for request: {0}", GetRequestUrl(cachedItem.Request));
CachedRequestResponse <T> newCachedItem = new CachedRequestResponse <T>();
newCachedItem.Request = cachedItem.Request;
newCachedItem.Data = this.ExecuteRestRequest <T>(cachedItem.Request);
newCachedItem.LastCached = DateTime.Now;
newCachedItem.Duration = cachedItem.Duration;
newCachedItem.KeepCurrent = true;
CacheItemPolicy policy = new CacheItemPolicy();
policy.AbsoluteExpiration = DateTimeOffset.Now.Add(cachedItem.Duration);
policy.UpdateCallback = CacheUpdated <T>;
arguments.UpdatedCacheItem = new CacheItem(arguments.Key, newCachedItem);
arguments.UpdatedCacheItemPolicy = policy;
//MemoryCache cache = MemoryCache.Default;
log.Debug("Request automatically recached.");
}
}
/// <summary>
/// Get a RestResponse from the cached based on the URL.
/// </summary>
/// <typeparam name="T">The RestResponse type to retrieve from the cache.</typeparam>
/// <param name="url">The url</param>
/// <returns></returns>
public T CachedExecute <T>(RestRequest request, CacheSettings settings) where T : new()
{
string key = GenerateCacheKey(request);
MemoryCache cache = MemoryCache.Default;
// Get the response from the cache
CachedRequestResponse <T> cachedItem = cache[key] as CachedRequestResponse <T>;
if (cachedItem == null)
{
log.DebugFormat("Response not cached, sending request");
cachedItem = new CachedRequestResponse <T>();
// Response not cached, so execute the request and get the response
cachedItem.Request = request;
cachedItem.Data = this.ExecuteRestRequest <T>(request);
cachedItem.LastCached = DateTime.Now;
cachedItem.Duration = settings.Duration;
cachedItem.KeepCurrent = settings.KeepCurrent;
CacheItemPolicy policy = new CacheItemPolicy();
policy.AbsoluteExpiration = DateTimeOffset.Now.Add(settings.Duration);
// Keep the cache updated if requested and it has expired
if (settings.KeepCurrent)
{
policy.UpdateCallback = CacheUpdated <T>;
}
cache.Set(key, cachedItem, policy);
log.DebugFormat("Response cached");
}
else
{
log.Debug("Response retrieved from cache.");
}
return(cachedItem.Data);;
}
