public IEnumerable<MsmqSubscription> LoadAll(string host)
{
SqlConnection connection = new SqlConnection(_connectionString);
using ( connection )
{
SqlCommand cmd = new SqlCommand("GetAllMsmqSubscriptions");
cmd.Connection = connection;
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("@host", host);
connection.Open();
using ( SqlDataReader reader = cmd.ExecuteReader() )
{
//List<MsmqSubscription> list = new List<MsmqSubscription>();
while ( reader.Read() )
{
MsmqSubscription subs = new MsmqSubscription();
subs.ID = reader.GetGuid(0);
subs.WorkflowInstance = reader.GetGuid(2);
subs.MsmqQueue = reader.GetString(3);
subs.WfQueueName = Deserialize(reader.GetSqlBytes(4));
//list.Add(subs);
yield return subs;
}
//return list;
}
}
}
//
// IMsmqSubscriptionPersistenceService Implementation
//
public void Persist(string host, MsmqSubscription subscription)
{
byte[] wfQueueName = Serialize(subscription.WfQueueName);
SqlConnection connection = new SqlConnection(_connectionString);
using ( connection )
{
SqlCommand cmd = new SqlCommand("InsertMsmqSubscription");
cmd.Connection = connection;
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("@subscriptionId", subscription.ID);
cmd.Parameters.AddWithValue("@host", host);
cmd.Parameters.AddWithValue("@workflowInstance",
subscription.WorkflowInstance);
cmd.Parameters.AddWithValue("@msmqQueue", subscription.MsmqQueue);
cmd.Parameters.AddWithValue("@wfQueueName", wfQueueName);
connection.Open();
cmd.ExecuteNonQuery();
}
}
public void Remove(MsmqSubscription subscription)
{
SqlConnection connection = new SqlConnection(_connectionString);
using ( connection )
{
SqlCommand cmd = new SqlCommand("RemoveMsmqSubscription");
cmd.Connection = connection;
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("@subscriptionId", subscription.ID);
connection.Open();
cmd.ExecuteNonQuery();
}
}
/// <summary>
/// Remove the specified susbcription
/// </summary>
/// <param name="subscription">Subscription to remove</param>
private void RemoveSubscription(MsmqSubscription subscription)
{
IMsmqSubscriptionPersistenceService svc =
Runtime.GetService<IMsmqSubscriptionPersistenceService>();
svc.Remove(subscription);
}
/// <summary>
/// Subscribe to messages received from an MSMQ Queue
/// </summary>
/// <param name="wfQueueName">Workflow Queue to post received messages to</param>
/// <param name="msmqQueue">MSMQ Queue to monitor</param>
/// <returns>The subscription ID</returns>
internal Guid Subscribe(IComparable wfQueueName, string msmqQueue)
{
if ( wfQueueName == null )
throw new ArgumentNullException("wfQueueName");
if ( String.IsNullOrEmpty(msmqQueue) )
throw new ArgumentNullException("msmqQueue");
MessageQueue queue = new MessageQueue(msmqQueue);
MsmqSubscription subscription = new MsmqSubscription();
subscription.WfQueueName = wfQueueName;
subscription.MsmqQueue = queue.FormatName;
subscription.WorkflowInstance =
WorkflowEnvironment.WorkflowInstanceId;
using ( TransactionScope scope = new TransactionScope() )
{
PersistSubscription(subscription);
ActivateSubscription(queue, subscription);
scope.Complete();
return subscription.ID;
}
}
//
// Private Methods
//
/// <summary>
/// Persist the specified subscription
/// </summary>
/// <param name="subscription">Subscription to Persist</param>
private void PersistSubscription(MsmqSubscription subscription)
{
IMsmqSubscriptionPersistenceService svc =
Runtime.GetService<IMsmqSubscriptionPersistenceService>();
svc.Persist(_hostname, subscription);
}
private void NotifyWorkflow(MsmqSubscription subscription, MessageDataEventArgs data)
{
TraceUtil.WriteInfo("MsmqListenerService::NotifyWorkflow({0}, {1})", subscription.MsmqQueue, subscription.WfQueueName);
WorkflowInstance instance =
Runtime.GetWorkflow(subscription.WorkflowInstance);
instance.EnqueueItem(subscription.WfQueueName, data, null, null);
}
/// <summary>
/// Activates a subscription by starting
/// to listen to the specified queue
/// </summary>
/// <param name="queue">Queue to activate</param>
/// <param name="subscription">Subscription to activate</param>
private void ActivateSubscription(MessageQueue queue, MsmqSubscription subscription)
{
try
{
_lock.AcquireWriterLock(Timeout.Infinite);
_subscriptionsByID.Add(subscription.ID, subscription);
// do we already have suscriptions to this queue?
Receiver receiver = null;
if ( !_queueReceivers.ContainsKey(queue.FormatName) )
{
receiver = new Receiver(queue, OnMessageReceived);
_queueReceivers.Add(queue.FormatName, receiver);
} else
{
receiver = _queueReceivers[queue.FormatName];
receiver.AddRef();
queue.Dispose();
}
} finally
{
_lock.ReleaseWriterLock();
}
}
public void Remove(MsmqSubscription subscription)
{
// do nothing
}
//
// IMsmqSubscriptionPersistenceService Implementation
//
public void Persist(string host, MsmqSubscription subscription)
{
// do nothing
}
