//public IFeedSession BeginFeed(TypeDescriptionConfig typeDescription, int packetSize, bool excludeFromEviction)
//{
// //RegisterTypeIfNeeded()
// //return new FeedSession<TItem>(packetSize, excludeFromEviction);
// throw new NotImplementedException();
//}
/// <summary>
/// As an alternative to <see cref="FeedMany{T}(IEnumerable{T},bool,int)" /> you can use
/// <see cref="BeginFeed{TItem}" /> <see cref="Add{TItem}" /> <see cref="EndFeed{TItem}" />
/// </summary>
/// <typeparam name="TItem"></typeparam>
/// <param name="session"></param>
/// <param name="item"></param>
public void Add <TItem>(IFeedSession session, TItem item) where TItem : class
{
var sessionImplementation = (FeedSession <TItem>)session;
if (sessionImplementation.IsClosed)
{
throw new CacheException("The feed session is closed");
}
var description = RegisterTypeIfNeeded(typeof(TItem));
var packedItem = CachedObject.Pack(item, description);
sessionImplementation.Request.Items.Add(packedItem);
if (sessionImplementation.Request.Items.Count == sessionImplementation.PacketSize)
{
var request = sessionImplementation.Request;
sessionImplementation.Request = null;
// only one packet at a time is fed asynchronously. If the previous send is still pending wait fot it to finish
sessionImplementation.WaitForAsyncCompletion();
ThreadPool.QueueUserWorkItem(state =>
{
try
{
var rq = (Request)state;
sessionImplementation.StartAsync();
var response = Channel.SendRequest(rq);
if (response is ExceptionResponse exResponse)
{
sessionImplementation.EndAsync(
new CacheException(
"Error while writing an object to the cache",
exResponse.Message, exResponse.CallStack));
}
else
{
sessionImplementation.EndAsync(null);
}
}
catch (Exception e)
{
sessionImplementation.EndAsync(e);
}
}, request);
// prepare a new empty put request that will receive new items
sessionImplementation.Request = new PutRequest(typeof(TItem));
}
}
/// <summary>
/// Close a feed session. Send all the remaining data and wait for all asynchronous operations to finish
/// </summary>
/// <typeparam name="TItem"></typeparam>
/// <param name="session"></param>
public void EndFeed <TItem>(IFeedSession session) where TItem : class
{
var sessionImplementation = (ParallelFeedSession <TItem>)session;
if (sessionImplementation.IsClosed)
{
throw new CacheException("The feed session is closed");
}
//send the last packet left for each node
for (var node = 0; node < CacheClients.Count; node++)
{
var request = sessionImplementation.Requests[node];
if (request != null && request.Items.Count > 0)
{
var n = node; // copy to avoid modified closure
var task = Task.Factory.StartNew(re =>
{
var response = CacheClients[n].Channel.SendRequest((Request)re);
if (response is ExceptionResponse exResponse)
{
throw new CacheException(
"Error while writing an object to the cache",
exResponse.Message, exResponse.CallStack);
}
}, request);
sessionImplementation.AddTask(task);
}
}
try
{
sessionImplementation.WaitForAll();
}
catch (AggregateException e)
{
if (e.InnerException != null)
{
throw e.InnerException;
}
}
sessionImplementation.IsClosed = true;
}
/// <summary>
/// As an alternative to <see cref="FeedMany{T}(IEnumerable{T},bool,int)" /> you can use
/// <see cref="BeginFeed{TItem}" /> <see cref="Add{TItem}" /> <see cref="EndFeed{TItem}" />
/// </summary>
/// <typeparam name="TItem"></typeparam>
/// <param name="session"></param>
public void EndFeed <TItem>(IFeedSession session) where TItem : class
{
var feedSession = (FeedSession <TItem>)session;
feedSession.WaitForAsyncCompletion();
// the last block is always send synchronously.
if (feedSession.Request.Items.Count > 0)
{
var response = Channel.SendRequest(feedSession.Request);
if (response is ExceptionResponse exResponse)
{
throw new CacheException("Error while writing an object to the cache", exResponse.Message,
exResponse.CallStack);
}
}
feedSession.IsClosed = true;
}
/// <summary>
/// Add an element to the cache during a fill session. Items are effectively send to the server in fixed size packets
/// </summary>
/// <typeparam name="TItem"></typeparam>
/// <param name="session"></param>
/// <param name="item"></param>
public void Add <TItem>(IFeedSession session, TItem item) where TItem : class
{
var sessionImplementation = (ParallelFeedSession <TItem>)session;
if (sessionImplementation.IsClosed)
{
throw new CacheException("The feed session is closed");
}
var description = RegisterTypeIfNeeded(typeof(TItem));
var packedItem = CachedObject.Pack(item, description);
var node = WhichNode(packedItem);
var request = sessionImplementation.Requests[node];
request.Items.Add(packedItem);
// for each node fill a packet of fixed size and send it to the server only when completed
if (request.Items.Count == sessionImplementation.PacketSize)
{
// create a new empty one for the future objects
sessionImplementation.Requests[node] = new PutRequest(typeof(TItem));
var task = Task.Factory.StartNew(re =>
{
var response = CacheClients[node].Channel.SendRequest((Request)re);
if (response is ExceptionResponse exResponse)
{
throw new CacheException(
"Error while writing an object to the cache",
exResponse.Message, exResponse.CallStack);
}
}, request);
sessionImplementation.AddTask(task);
}
}
