// NpgsqlResourceManager.cs
//
// Author:
// Josh Cooley
//
// Copyright (C) 2007, The Npgsql Development Team
//
// Permission to use, copy, modify, and distribute this software and its
// documentation for any purpose, without fee, and without a written
// agreement is hereby granted, provided that the above copyright notice
// and this paragraph and the following two paragraphs appear in all copies.
//
// IN NO EVENT SHALL THE NPGSQL DEVELOPMENT TEAM BE LIABLE TO ANY PARTY
// FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES,
// INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
// DOCUMENTATION, EVEN IF THE NPGSQL DEVELOPMENT TEAM HAS BEEN ADVISED OF
// THE POSSIBILITY OF SUCH DAMAGE.
//
// THE NPGSQL DEVELOPMENT TEAM SPECIFICALLY DISCLAIMS ANY WARRANTIES,
// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
// ON AN "AS IS" BASIS, AND THE NPGSQL DEVELOPMENT TEAM HAS NO OBLIGATIONS
// TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
using System;
using System.Collections.Generic;
using System.Transactions;
namespace Npgsql
{
internal interface INpgsqlResourceManager
{
void Enlist(INpgsqlTransactionCallbacks transactionCallbacks, byte[] txToken);
byte[] Promote(INpgsqlTransactionCallbacks transactionCallbacks);
void CommitWork(string txName);
void RollbackWork(string txName);
}
internal class NpgsqlResourceManager : MarshalByRefObject, INpgsqlResourceManager
{
private readonly Dictionary _transactions = new Dictionary();
#region INpgsqlTransactionManager Members
public byte[] Promote(INpgsqlTransactionCallbacks callbacks)
{
CommittableTransaction tx = new CommittableTransaction();
DurableResourceManager rm = new DurableResourceManager(this, callbacks, tx);
byte[] token = TransactionInterop.GetTransmitterPropagationToken(tx);
_transactions.Add(rm.TxName, tx);
rm.Enlist(tx);
return token;
}
public void Enlist(INpgsqlTransactionCallbacks callbacks, byte[] txToken)
{
DurableResourceManager rm = new DurableResourceManager(this, callbacks);
rm.Enlist(txToken);
}
public void CommitWork(string txName)
{
CommittableTransaction tx;
if (_transactions.TryGetValue(txName, out tx))
{
tx.Commit();
_transactions.Remove(txName);
}
}
public void RollbackWork(string txName)
{
CommittableTransaction tx;
if (_transactions.TryGetValue(txName, out tx))
{
_transactions.Remove(txName);
// you can fail to commit,
// but you're not getting out
// of a rollback. Remove from list first.
tx.Rollback();
}
}
#endregion
private class DurableResourceManager : ISinglePhaseNotification
{
private CommittableTransaction _tx;
private NpgsqlResourceManager _rm;
private readonly INpgsqlTransactionCallbacks _callbacks;
private string _txName;
public DurableResourceManager(NpgsqlResourceManager rm, INpgsqlTransactionCallbacks callbacks)
: this(rm, callbacks, null)
{
}
public DurableResourceManager(NpgsqlResourceManager rm, INpgsqlTransactionCallbacks callbacks,
CommittableTransaction tx)
{
_rm = rm;
_tx = tx;
_callbacks = callbacks;
}
public string TxName
{
get
{
// delay initialize since callback methods may be expensive
if (_txName == null)
{
_txName = _callbacks.GetName();
}
return _txName;
}
}
#region IEnlistmentNotification Members
public void Commit(Enlistment enlistment)
{
_callbacks.CommitTransaction();
// TODO: remove record of prepared
enlistment.Done();
_callbacks.Dispose();
}
public void InDoubt(Enlistment enlistment)
{
// not going to happen when enlisted durably
throw new NotImplementedException();
}
public void Prepare(PreparingEnlistment preparingEnlistment)
{
_callbacks.PrepareTransaction();
// TODO: record prepared
preparingEnlistment.Prepared();
}
public void Rollback(Enlistment enlistment)
{
_callbacks.RollbackTransaction();
// TODO: remove record of prepared
enlistment.Done();
_callbacks.Dispose();
}
#endregion
#region ISinglePhaseNotification Members
public void SinglePhaseCommit(SinglePhaseEnlistment singlePhaseEnlistment)
{
_callbacks.CommitTransaction();
singlePhaseEnlistment.Committed();
_callbacks.Dispose();
}
#endregion
private static readonly Guid rmGuid = new Guid("9e1b6d2d-8cdb-40ce-ac37-edfe5f880716");
public Transaction Enlist(byte[] token)
{
return Enlist(TransactionInterop.GetTransactionFromTransmitterPropagationToken(token));
}
public Transaction Enlist(Transaction tx)
{
tx.EnlistDurable(rmGuid, this, EnlistmentOptions.None);
return tx;
}
}
}
}