/// <summary>
/// When overriden, defines the custom behavior to be invoked after attempting to save the specified <paramref name="saga"/>.
/// </summary>
/// <param name="saga">The modified <see cref="Saga"/> instance if <paramref name="error"/> is <value>null</value>; otherwise the original <see cref="Saga"/> instance if <paramref name="error"/> is not <value>null</value>.</param>
/// <param name="context">The current <see cref="SagaContext"/> assocaited with the pending saga modifications.</param>
/// <param name="error">The <see cref="Exception"/> thrown if the save was unsuccessful; otherwise <value>null</value>.</param>
public override void PostSave(Saga saga, SagaContext context, Exception error)
{
base.PostSave(saga, context, error);
if (error is ConcurrencyException)
statistics.IncrementConflictCount();
}
/// <summary>
/// Invokes zero or more customized <see cref="PipelineHook.PostSave"/> implementations.
/// </summary>
/// <param name="saga">The modified <see cref="Saga"/> instance if <paramref name="error"/> is <value>null</value>; otherwise the original <see cref="Saga"/> instance if <paramref name="error"/> is not <value>null</value>.</param>
/// <param name="context">The current <see cref="SagaContext"/> assocaited with the pending saga modifications.</param>
/// <param name="error">The <see cref="Exception"/> thrown if the save was unsuccessful; otherwise <value>null</value>.</param>
private void InvokePostSaveHooks(Saga saga, SagaContext context, Exception error)
{
foreach (var pipelineHook in postSaveHooks)
{
Log.Trace("Invoking post-save pipeline hook: {0}", pipelineHook);
pipelineHook.PostSave(saga, context, error);
}
}
/// <summary>
/// Invokes zero or more customized <see cref="PipelineHook.PreSave"/> implementations.
/// </summary>
/// <param name="saga">The saga to be modified by the current <paramref name="context"/>.</param>
/// <param name="context">The current <see cref="SagaContext"/> associated with the pending saga modifications.</param>
private void InvokePreSaveHooks(Saga saga, SagaContext context)
{
foreach (var pipelineHook in preSaveHooks)
{
Log.Trace("Invoking pre-save pipeline hook: {0}", pipelineHook);
pipelineHook.PreSave(saga, context);
}
}
/// <summary>
/// Invokes zero or more customized <see cref="PipelineHook.PostGet"/> implementations.
/// </summary>
/// <param name="saga">The loaded saga instance.</param>
private void InvokePostGetHooks(Saga saga)
{
foreach (var pipelineHook in postGetHooks)
{
Log.Trace("Invoking post-get pipeline hook: {0}", pipelineHook);
pipelineHook.PostGet(saga);
}
}
/// <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)
{
Boolean result;
InvokePreGetHooks(type, id);
result = sagaStore.TryGetSaga(type, id, out saga);
InvokePostGetHooks(saga);
return(result);
}
/// <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)
{
InvokePreSaveHooks(saga, context);
try
{
var result = sagaStore.Save(saga, context);
InvokePostSaveHooks(result, context, null);
return(result);
}
catch (Exception ex)
{
InvokePostSaveHooks(saga, context, ex);
throw;
}
}
/// <summary>
/// When overriden, defines the custom behavior to be invoked after attempting to save the specified <paramref name="saga"/>.
/// </summary>
/// <param name="saga">The modified <see cref="Saga"/> instance if <paramref name="error"/> is <value>null</value>; otherwise the original <see cref="Saga"/> instance if <paramref name="error"/> is not <value>null</value>.</param>
/// <param name="context">The current <see cref="SagaContext"/> assocaited with the pending saga modifications.</param>
/// <param name="error">The <see cref="Exception"/> thrown if the save was unsuccessful; otherwise <value>null</value>.</param>
public override void PostSave(Saga saga, SagaContext context, Exception error)
{
if (!context.TimeoutChanged || saga == null || error != null)
{
return;
}
if (saga.Timeout.HasValue && !saga.Completed)
{
var timeout = saga.Timeout.Value;
TimeoutCache.ScheduleTimeout(new SagaTimeout(saga.GetType(), saga.CorrelationId, timeout));
}
else
{
TimeoutCache.ClearTimeout(new SagaReference(saga.GetType(), saga.CorrelationId));
}
RescheduleTimer(TimeoutCache.GetNextScheduledTimeout());
}
/// <summary>
/// Handles the <paramref name="saga"/> event.
/// </summary>
/// <param name="saga">The saga instance handling the event.</param>
/// <param name="e">The event to be handled.</param>
protected override void HandleSagaEvent(Saga saga, Event e)
{
var timeout = ((Timeout)e).Scheduled;
if (saga.Timeout.HasValue)
{
if (saga.Timeout.Value == timeout)
{
saga.ClearTimeout();
base.HandleSagaEvent(saga, e);
}
else
{
Log.Warn("{0} received unexpected timeout at {1} when scheduled timeout is for {2}", saga, timeout.ToString(DateTimeFormat.RoundTrip), saga.Timeout.Value.ToString(DateTimeFormat.RoundTrip));
}
}
else
{
Log.Warn("{0} received unexpected timeout at {1} when no timeout is scheduled", saga, timeout.ToString(DateTimeFormat.RoundTrip));
}
}
/// <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>
/// Handles the <paramref name="saga"/> event.
/// </summary>
/// <param name="saga">The saga instance handling the event.</param>
/// <param name="e">The event to be handled.</param>
protected override void HandleSagaEvent(Saga saga, Event e)
{
var timeout = ((Timeout)e).Scheduled;
if (saga.Timeout.HasValue)
{
if (saga.Timeout.Value == timeout)
{
saga.ClearTimeout();
base.HandleSagaEvent(saga, e);
}
else
{
Log.Warn("{0} received unexpected timeout at {1} when scheduled timeout is for {2}", saga, timeout.ToString(DateTimeFormat.RoundTrip), saga.Timeout.Value.ToString(DateTimeFormat.RoundTrip));
}
}
else
{
Log.Warn("{0} received unexpected timeout at {1} when no timeout is scheduled", saga, timeout.ToString(DateTimeFormat.RoundTrip));
}
}
/// <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;
}
}
}
/// <summary>
/// Handles the <paramref name="saga"/> event.
/// </summary>
/// <param name="saga">The saga instance handling the event.</param>
/// <param name="e">The event to be handled.</param>
protected virtual void HandleSagaEvent(Saga saga, Event e)
{
Log.Trace("{0} handling event {1}", saga, e);
Executor(saga, e);
}
/// <summary>
/// Invokes zero or more customized <see cref="PipelineHook.PostSave"/> implementations.
/// </summary>
/// <param name="saga">The modified <see cref="Saga"/> instance if <paramref name="error"/> is <value>null</value>; otherwise the original <see cref="Saga"/> instance if <paramref name="error"/> is not <value>null</value>.</param>
/// <param name="context">The current <see cref="SagaContext"/> assocaited with the pending saga modifications.</param>
/// <param name="error">The <see cref="Exception"/> thrown if the save was unsuccessful; otherwise <value>null</value>.</param>
private void InvokePostSaveHooks(Saga saga, SagaContext context, Exception error)
{
foreach (var pipelineHook in postSaveHooks)
{
Log.Trace("Invoking post-save pipeline hook: {0}", pipelineHook);
pipelineHook.PostSave(saga, context, error);
}
}
/// <summary>
/// Invokes zero or more customized <see cref="PipelineHook.PreSave"/> implementations.
/// </summary>
/// <param name="saga">The saga to be modified by the current <paramref name="context"/>.</param>
/// <param name="context">The current <see cref="SagaContext"/> associated with the pending saga modifications.</param>
private void InvokePreSaveHooks(Saga saga, SagaContext context)
{
foreach (var pipelineHook in preSaveHooks)
{
Log.Trace("Invoking pre-save pipeline hook: {0}", pipelineHook);
pipelineHook.PreSave(saga, context);
}
}
/// <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)
{
Boolean result;
InvokePreGetHooks(type, id);
result = sagaStore.TryGetSaga(type, id, out saga);
InvokePostGetHooks(saga);
return result;
}
/// <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)
{
var result = sagaStore.TryGetSaga(type, id, out saga);
statistics.IncrementQueryCount();
return result;
}
/// <summary>
/// When overriden, defines the custom behavior to be invoked prior to saving the specified <paramref name="saga"/>.
/// </summary>
/// <param name="saga">The saga to be modified using the current <paramref name="context"/>.</param>
/// <param name="context">The current <see cref="SagaContext"/> assocaited with the pending saga modifications.</param>
public virtual void PreSave(Saga saga, SagaContext context)
{
}
/// <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)
{
InvokePreSaveHooks(saga, context);
try
{
var result = sagaStore.Save(saga, context);
InvokePostSaveHooks(result, context, null);
return result;
}
catch (Exception ex)
{
InvokePostSaveHooks(saga, context, ex);
throw;
}
}
/// <summary>
/// Handles the <paramref name="saga"/> event.
/// </summary>
/// <param name="saga">The saga instance handling the event.</param>
/// <param name="e">The event to be handled.</param>
protected virtual void HandleSagaEvent(Saga saga, Event e)
{
Log.Trace("{0} handling event {1}", saga, e);
Executor(saga, e);
}
/// <summary>
/// When overriden, defines the custom behavior to be invokes after successfully retrieving the specified <paramref name="saga"/>.
/// </summary>
/// <param name="saga">The loaded saga instance.</param>
public virtual void PostGet(Saga saga)
{
}
/// <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)
{
var result = sagaStore.Save(saga, context);
if (saga.Version == 1)
{
statistics.IncrementInsertCount();
}
else
{
if (saga.Completed)
{
statistics.IncrementDeleteCount();
}
else
{
statistics.IncrementUpdateCount();
}
}
return result;
}
/// <summary>
/// When overriden, defines the custom behavior to be invokes after successfully retrieving the specified <paramref name="saga"/>.
/// </summary>
/// <param name="saga">The loaded saga instance.</param>
public virtual void PostGet(Saga saga)
{
}
/// <summary>
/// Invokes zero or more customized <see cref="PipelineHook.PostGet"/> implementations.
/// </summary>
/// <param name="saga">The loaded saga instance.</param>
private void InvokePostGetHooks(Saga saga)
{
foreach (var pipelineHook in postGetHooks)
{
Log.Trace("Invoking post-get pipeline hook: {0}", pipelineHook);
pipelineHook.PostGet(saga);
}
}
/// <summary>
/// When overriden, defines the custom behavior to be invoked after attempting to save the specified <paramref name="saga"/>.
/// </summary>
/// <param name="saga">The modified <see cref="Saga"/> instance if <paramref name="error"/> is <value>null</value>; otherwise the original <see cref="Saga"/> instance if <paramref name="error"/> is not <value>null</value>.</param>
/// <param name="context">The current <see cref="SagaContext"/> assocaited with the pending saga modifications.</param>
/// <param name="error">The <see cref="Exception"/> thrown if the save was unsuccessful; otherwise <value>null</value>.</param>
public virtual void PostSave(Saga saga, SagaContext context, Exception error)
{
}
/// <summary>
/// When overriden, defines the custom behavior to be invoked after attempting to save the specified <paramref name="saga"/>.
/// </summary>
/// <param name="saga">The modified <see cref="Saga"/> instance if <paramref name="error"/> is <value>null</value>; otherwise the original <see cref="Saga"/> instance if <paramref name="error"/> is not <value>null</value>.</param>
/// <param name="context">The current <see cref="SagaContext"/> assocaited with the pending saga modifications.</param>
/// <param name="error">The <see cref="Exception"/> thrown if the save was unsuccessful; otherwise <value>null</value>.</param>
public virtual void PostSave(Saga saga, SagaContext context, Exception error)
{
}
/// <summary>
/// When overriden, defines the custom behavior to be invoked after attempting to save the specified <paramref name="saga"/>.
/// </summary>
/// <param name="saga">The modified <see cref="Saga"/> instance if <paramref name="error"/> is <value>null</value>; otherwise the original <see cref="Saga"/> instance if <paramref name="error"/> is not <value>null</value>.</param>
/// <param name="context">The current <see cref="SagaContext"/> assocaited with the pending saga modifications.</param>
/// <param name="error">The <see cref="Exception"/> thrown if the save was unsuccessful; otherwise <value>null</value>.</param>
public override void PostSave(Saga saga, SagaContext context, Exception error)
{
if (!context.TimeoutChanged || saga == null || error != null)
return;
if (saga.Timeout.HasValue && !saga.Completed)
{
var timeout = saga.Timeout.Value;
TimeoutCache.ScheduleTimeout(new SagaTimeout(saga.GetType(), saga.CorrelationId, timeout));
}
else
{
TimeoutCache.ClearTimeout(new SagaReference(saga.GetType(), saga.CorrelationId));
}
RescheduleTimer(TimeoutCache.GetNextScheduledTimeout());
}
/// <summary>
/// When overriden, defines the custom behavior to be invoked prior to saving the specified <paramref name="saga"/>.
/// </summary>
/// <param name="saga">The saga to be modified using the current <paramref name="context"/>.</param>
/// <param name="context">The current <see cref="SagaContext"/> assocaited with the pending saga modifications.</param>
public virtual void PreSave(Saga saga, SagaContext context)
{
}