/// <summary>
/// Save the specified <paramref name="context"/> changes for the given <paramref name="saga"/>.
/// </summary>
/// <param name="saga">The current saga version for which the context applies.</param>
/// <param name="context">The saga context containing the saga changes to be applied.</param>
public Saga Save(Saga saga, SagaContext context)
{
Verify.NotNull(saga, nameof(saga));
Verify.NotNull(context, nameof(context));
var sagaType = saga.GetType();
var key = String.Concat(sagaType.GetFullNameWithAssembly(), "-", saga.CorrelationId);
using (var sagaLock = new SagaLock(sagaType, saga.CorrelationId))
{
sagaLock.Aquire();
try
{
sagaStore.Save(saga, context);
if (saga.Completed)
{
memoryCache.Remove(key);
}
else
{
memoryCache.Set(key, saga, CreateCacheItemPolicy());
}
return(saga);
}
catch (ConcurrencyException)
{
memoryCache.Remove(key);
throw;
}
}
}
/// <summary>
/// Attempt to retrieve an existing saga instance identified by the specified <paramref name="type"/> and <paramref name="id"/>.
/// </summary>
/// <param name="type">The type of saga to be retrieved.</param>
/// <param name="id">The correlation id of the saga to be retrieved.</param>
/// <param name="saga">The <see cref="Saga"/> instance if found; otherwise <value>null</value>.</param>
public Boolean TryGetSaga(Type type, Guid id, out Saga saga)
{
Verify.NotNull(type, nameof(type));
var key = String.Concat(type.GetFullNameWithAssembly(), "-", id);
using (var sagaLock = new SagaLock(type, id))
{
sagaLock.Aquire();
//NOTE: We do not want to cache a NULL saga reference, thus explicitly check for existance and add to cache if instance found.
saga = (Saga)memoryCache.Get(key);
if (saga == null && sagaStore.TryGetSaga(type, id, out saga))
{
memoryCache.Add(key, saga, CreateCacheItemPolicy());
}
}
//NOTE: Given that saga state is modified during `Handling`, we must always return a copy of the cached instance.
return((saga == null ? null : saga = saga.Copy()) != null);
}
/// <summary>
/// Attempt to retrieve an existing saga instance identified by the specified <paramref name="type"/> and <paramref name="id"/>.
/// </summary>
/// <param name="type">The type of saga to be retrieved.</param>
/// <param name="id">The correlation id of the saga to be retrieved.</param>
/// <param name="saga">The <see cref="Saga"/> instance if found; otherwise <value>null</value>.</param>
public Boolean TryGetSaga(Type type, Guid id, out Saga saga)
{
Verify.NotNull(type, nameof(type));
var key = String.Concat(type.GetFullNameWithAssembly(), "-", id);
using (var sagaLock = new SagaLock(type, id))
{
sagaLock.Aquire();
//NOTE: We do not want to cache a NULL saga reference, thus explicitly check for existance and add to cache if instance found.
saga = (Saga)memoryCache.Get(key);
if (saga == null && sagaStore.TryGetSaga(type, id, out saga))
memoryCache.Add(key, saga, CreateCacheItemPolicy());
}
//NOTE: Given that saga state is modified during `Handling`, we must always return a copy of the cached instance.
return (saga == null ? null : saga = saga.Copy()) != null;
}
/// <summary>
/// Save the specified <paramref name="context"/> changes for the given <paramref name="saga"/>.
/// </summary>
/// <param name="saga">The current saga version for which the context applies.</param>
/// <param name="context">The saga context containing the saga changes to be applied.</param>
public Saga Save(Saga saga, SagaContext context)
{
Verify.NotNull(saga, nameof(saga));
Verify.NotNull(context, nameof(context));
var sagaType = saga.GetType();
var key = String.Concat(sagaType.GetFullNameWithAssembly(), "-", saga.CorrelationId);
using (var sagaLock = new SagaLock(sagaType, saga.CorrelationId))
{
sagaLock.Aquire();
try
{
sagaStore.Save(saga, context);
if (saga.Completed)
memoryCache.Remove(key);
else
memoryCache.Set(key, saga, CreateCacheItemPolicy());
return saga;
}
catch (ConcurrencyException)
{
memoryCache.Remove(key);
throw;
}
}
}
