private void LoadCompleted(ClientMessage.ReadStreamEventsBackwardCompleted completed)
{
if (completed.Result == ReadStreamResult.Success && completed.Events.Length == 1)
{
byte[] state = completed.Events[0].Event.Data;
var persistedState = state.ParseJson <PersistedState>();
_lastWrittenVersion = completed.Events[0].Event.EventNumber;
FixUpOldFormat(completed, persistedState);
FixupOldProjectionModes(persistedState);
FixUpOldProjectionRunAs(persistedState);
LoadPersistedState(persistedState);
//TODO: encapsulate this into managed projection
_state = ManagedProjectionState.Loaded;
if (Enabled && _enabledToRun)
{
if (Mode >= ProjectionMode.Continuous)
{
Prepare(() => Start(() => { }));
}
}
else
{
CreatePrepared(() => LoadStopped(() => { }));
}
return;
}
_state = ManagedProjectionState.Creating;
_logger.Trace(
"Projection manager did not find any projection configuration records in the {0} stream. Projection stays in CREATING state",
completed.EventStreamId);
}
private void BeginCreatePrepared(ProjectionConfig config, Action onPrepared)
{
_onPrepared = onPrepared;
if (config == null)
{
throw new ArgumentNullException("config");
}
//TODO: which states are allowed here?
if (_state >= ManagedProjectionState.Preparing)
{
DisposeCoreProjection();
_state = ManagedProjectionState.Loaded;
}
//TODO: load configuration from the definition
if (_persistedState.SourceDefinition == null)
{
throw new Exception(
"The projection cannot be loaded as stopped as it was stored in the old format. Update the projection query text to force prepare");
}
var createProjectionMessage =
new CoreProjectionManagementMessage.CreatePrepared(
new PublishEnvelope(_inputQueue), Id, _name,
new ProjectionVersion(_projectionId, _persistedState.Epoch ?? 0, _persistedState.Version ?? 1),
config, _persistedState.SourceDefinition, HandlerType, Query);
//note: set running before start as coreProjection.start() can respond with faulted
_state = ManagedProjectionState.Preparing;
_coreQueue.Publish(createProjectionMessage);
}
private void Stop(Action completed)
{
switch (_state)
{
case ManagedProjectionState.Stopped:
case ManagedProjectionState.Faulted:
if (completed != null)
{
completed();
}
return;
case ManagedProjectionState.Loading:
case ManagedProjectionState.Creating:
throw new InvalidOperationException(
string.Format(
"Cannot stop a projection in the '{0}' state",
Enum.GetName(typeof(ManagedProjectionState), _state)));
case ManagedProjectionState.Stopping:
_stopCompleted += completed;
return;
case ManagedProjectionState.Running:
_state = ManagedProjectionState.Stopping;
_stopCompleted = completed;
_coreQueue.Publish(new ProjectionMessage.Projections.Management.Stop(_id));
break;
default:
throw new NotSupportedException();
}
}
internal void SetState(ManagedProjectionState value)
{
// _logger.Trace("MP: {0} {1} => {2}", _name, _state, value);
_state = value;
switch (value)
{
case ManagedProjectionState.Aborted:
_stateHandler = new AbortedState(this);
break;
case ManagedProjectionState.Aborting:
_stateHandler = new AbortingState(this);
break;
case ManagedProjectionState.Completed:
_stateHandler = new CompletedState(this);
break;
case ManagedProjectionState.Creating:
case ManagedProjectionState.Loading:
case ManagedProjectionState.Loaded:
_stateHandler = new CreatingLoadingLoadedState(this);
break;
case ManagedProjectionState.Faulted:
_stateHandler = new FaultedState(this);
break;
case ManagedProjectionState.LoadingStopped:
_stateHandler = new LoadingStateState(this);
break;
case ManagedProjectionState.Prepared:
_stateHandler = new PreparedState(this);
break;
case ManagedProjectionState.Preparing:
_stateHandler = new PreparingState(this);
break;
case ManagedProjectionState.Running:
_stateHandler = new RunningState(this);
break;
case ManagedProjectionState.Starting:
_stateHandler = new StartingState(this);
break;
case ManagedProjectionState.Stopped:
_stateHandler = new StoppedState(this);
break;
case ManagedProjectionState.Stopping:
_stateHandler = new StoppingState(this);
break;
default:
throw new Exception();
}
}
private void StartNew(Action completed)
{
_state = ManagedProjectionState.Stopped;
StartIfEnabled();
if (completed != null)
{
completed();
}
}
protected override IEnumerable<WhenStep> When()
{
_projectionId = Guid.NewGuid();
_bufferedEvents = 100;
_checkpointStatus = "checkpoint-status";
_coreProcessingTime = 10;
_resultStreamName = "result-stream";
_effectiveName = "effective-name";
_enabled = true;
_epoch = 10;
_eventsProcessedAfterRestart = 12345;
_lastCheckpoint = "last-chgeckpoint";
_masterStatus = ManagedProjectionState.Completed;
_mode = ProjectionMode.OneTime;
_partitionsCached = 123;
_name = "name";
_position = CheckpointTag.FromPosition(0, 1000, 900).ToString();
_progress = 100;
_projectionIdNum = 1234;
_readsInProgress = 2;
_stateReason = "reason";
_status = "status";
_version = 1;
_writePendingEventsAfterCheckpoint = 3;
_writePendingEventsBeforeCheckpoint = 4;
_writesInProgress = 5;
yield return CreateWriteEvent("$projections-$master", "$statistics-report", @"{
""id"":""" + _projectionId.ToString("N") + @""",
""statistics"":{
""bufferedEvents"":""" + _bufferedEvents + @""",
""checkpointStatus"":""" + _checkpointStatus + @""",
""coreProcessingTime"":""" + _coreProcessingTime + @""",
""resultStreamName"":""" + _resultStreamName + @""",
""effectiveName"":""" + _effectiveName + @""",
""enabled"":""" + _enabled + @""",
""epoch"":""" + _epoch + @""",
""eventsProcessedAfterRestart"":""" + _eventsProcessedAfterRestart + @""",
""lastCheckpoint"":""" + _lastCheckpoint + @""",
""masterStatus"":""" + _masterStatus + @""",
""mode"":""" + _mode + @""",
""partitionsCached"":""" + _partitionsCached + @""",
""name"":""" + _name + @""",
""position"":""" + _position + @""",
""progress"":""" + _progress + @""",
""projectionId"":""" + _projectionIdNum + @""",
""readsInProgress"":""" + _readsInProgress + @""",
""stateReason"":""" + _stateReason + @""",
""status"":""" + _status + @""",
""version"":""" + _version + @""",
""writePendingEventsAfterCheckpoint"":""" + _writePendingEventsAfterCheckpoint + @""",
""writePendingEventsBeforeCheckpoint"":""" + _writePendingEventsBeforeCheckpoint + @""",
""writesInProgress"":""" + _writesInProgress + @""",
}
}", null, true);
}
protected override IEnumerable <WhenStep> When()
{
_projectionId = Guid.NewGuid();
_bufferedEvents = 100;
_checkpointStatus = "checkpoint-status";
_coreProcessingTime = 10;
_resultStreamName = "result-stream";
_effectiveName = "effective-name";
_enabled = true;
_epoch = 10;
_eventsProcessedAfterRestart = 12345;
_lastCheckpoint = "last-chgeckpoint";
_masterStatus = ManagedProjectionState.Completed;
_mode = ProjectionMode.OneTime;
_partitionsCached = 123;
_name = "name";
_position = CheckpointTag.FromPosition(0, 1000, 900).ToString();
_progress = 100;
_projectionIdNum = 1234;
_readsInProgress = 2;
_stateReason = "reason";
_status = "status";
_version = 1;
_writePendingEventsAfterCheckpoint = 3;
_writePendingEventsBeforeCheckpoint = 4;
_writesInProgress = 5;
yield return(CreateWriteEvent("$projections-$master", "$statistics-report", @"{
""id"":""" + _projectionId.ToString("N") + @""",
""statistics"":{
""bufferedEvents"":""" + _bufferedEvents + @""",
""checkpointStatus"":""" + _checkpointStatus + @""",
""coreProcessingTime"":""" + _coreProcessingTime + @""",
""resultStreamName"":""" + _resultStreamName + @""",
""effectiveName"":""" + _effectiveName + @""",
""enabled"":""" + _enabled + @""",
""epoch"":""" + _epoch + @""",
""eventsProcessedAfterRestart"":""" + _eventsProcessedAfterRestart + @""",
""lastCheckpoint"":""" + _lastCheckpoint + @""",
""masterStatus"":""" + _masterStatus + @""",
""mode"":""" + _mode + @""",
""partitionsCached"":""" + _partitionsCached + @""",
""name"":""" + _name + @""",
""position"":""" + _position + @""",
""progress"":""" + _progress + @""",
""projectionId"":""" + _projectionIdNum + @""",
""readsInProgress"":""" + _readsInProgress + @""",
""stateReason"":""" + _stateReason + @""",
""status"":""" + _status + @""",
""version"":""" + _version + @""",
""writePendingEventsAfterCheckpoint"":""" + _writePendingEventsAfterCheckpoint + @""",
""writePendingEventsBeforeCheckpoint"":""" + _writePendingEventsBeforeCheckpoint + @""",
""writesInProgress"":""" + _writesInProgress + @""",
}
}", null, true));
}
private void BeginCreateAndPrepare(
ProjectionStateHandlerFactory handlerFactory, ProjectionConfig config,
Action onPrepared)
{
_onPrepared = onPrepared;
if (handlerFactory == null)
{
throw new ArgumentNullException("handlerFactory");
}
if (config == null)
{
throw new ArgumentNullException("config");
}
//TODO: which states are allowed here?
if (_state >= ManagedProjectionState.Preparing)
{
throw new InvalidOperationException("Already preparing or has been prepared");
}
//TODO: load configuration from the definition
var createProjectionMessage =
new CoreProjectionManagementMessage.CreateAndPrepare(
new PublishEnvelope(_inputQueue), _id, _name, config, delegate
{
// this delegate runs in the context of a projection core thread
// TODO: move this code to the projection core service as we may be in different processes in the future
IProjectionStateHandler stateHandler = null;
try
{
stateHandler = handlerFactory.Create(HandlerType, Query, Console.WriteLine);
var checkpointStrategyBuilder = new CheckpointStrategy.Builder();
stateHandler.ConfigureSourceProcessingStrategy(checkpointStrategyBuilder);
checkpointStrategyBuilder.Validate(Mode); // avoid future exceptions in coreprojection
return(stateHandler);
}
catch (Exception ex)
{
SetFaulted(
string.Format(
"Cannot create a projection state handler.\r\n\r\nHandler type: {0}\r\nQuery:\r\n\r\n{1}\r\n\r\nMessage:\r\n\r\n{2}",
HandlerType, Query, ex.Message), ex);
if (stateHandler != null)
{
stateHandler.Dispose();
}
throw;
}
});
//note: set runnign before start as coreProjection.start() can respond with faulted
_state = ManagedProjectionState.Preparing;
_coreQueue.Publish(createProjectionMessage);
}
private void Start(Action onStarted)
{
if (!Enabled)
{
throw new InvalidOperationException("Projection is disabled");
}
_onStarted = onStarted;
_state = ManagedProjectionState.Starting;
_coreQueue.Publish(new CoreProjectionManagementMessage.Start(_id));
}
public void Handle(CoreProjectionManagementMessage.Started message)
{
_state = ManagedProjectionState.Running;
if (_onStarted != null)
{
var action = _onStarted;
_onStarted = null;
action();
}
}
public void Handle(ProjectionMessage.Projections.StatusReport.Stopped message)
{
_state = ManagedProjectionState.Stopped;
DisposeCoreProjection();
var stopCompleted = _stopCompleted;
_stopCompleted = null;
if (stopCompleted != null)
{
stopCompleted();
}
}
public void Handle(CoreProjectionManagementMessage.Prepared message)
{
_persistedState.SourceDefinition = message.SourceDefinition;
if (_state == ManagedProjectionState.Preparing)
{
_state = ManagedProjectionState.Prepared;
OnPrepared();
}
else
{
_logger.Trace("Received prepared without being prepared");
}
}
private void SetFaulted(string reason, Exception ex = null)
{
if (ex != null)
{
_logger.ErrorException(ex, "The '{0}' projection faulted due to '{1}'", _name, reason);
}
else
{
_logger.Error("The '{0}' projection faulted due to '{1}'", _name, reason);
}
_state = ManagedProjectionState.Faulted;
_faultedReason = reason;
}
private void Start(IPublisher coreOutput, ProjectionStateHandlerFactory handlerFactory, ProjectionConfig config)
{
if (coreOutput == null)
{
throw new ArgumentNullException("coreOutput");
}
if (handlerFactory == null)
{
throw new ArgumentNullException("handlerFactory");
}
if (config == null)
{
throw new ArgumentNullException("config");
}
if (_coreProjection != null)
{
throw new InvalidOperationException("CoreProjection has been already created");
}
IProjectionStateHandler stateHandler = null;
try
{
stateHandler = handlerFactory.Create(HandlerType, Query, Console.WriteLine);
var checkpointStrategyBuilder = new CheckpointStrategy.Builder();
stateHandler.ConfigureSourceProcessingStrategy(checkpointStrategyBuilder);
checkpointStrategyBuilder.Validate(this.Mode); // avoid future exceptions in coreprojection
// constructor can fail if wrong source defintion
//TODO: revise it
_coreProjection = new CoreProjection(_name, _id, coreOutput, stateHandler, config, _logger);
}
catch (Exception ex)
{
SetFaulted(
String.Format(
"Cannot create a projection state handler.\r\n\r\nHandler type: {0}\r\nQuery:\r\n\r\n{1}\r\n\r\nMessage:\r\n\r\n{2}",
HandlerType, Query, ex.Message), ex);
if (stateHandler != null)
{
stateHandler.Dispose();
}
return;
}
//TODO: load configuration from the definition
_state = ManagedProjectionState.Running;
//note: set runnign before start as coreProjection.start() can respond with faulted
_coreProjection.Start();
}
private void Start(ProjectionStateHandlerFactory handlerFactory, ProjectionConfig config)
{
if (handlerFactory == null)
{
throw new ArgumentNullException("handlerFactory");
}
if (config == null)
{
throw new ArgumentNullException("config");
}
if (_state == ManagedProjectionState.Running)
{
throw new InvalidOperationException("Already started");
}
//TODO: load configuration from the definition
var createProjectionMessage = new ProjectionMessage.CoreService.Management.Create(new PublishEnvelope(_inputQueue), _id, _name, config, delegate
{
IProjectionStateHandler stateHandler = null;
try
{
stateHandler = handlerFactory.Create(this.HandlerType, this.Query, Console.WriteLine);
var checkpointStrategyBuilder = new CheckpointStrategy.Builder();
stateHandler.ConfigureSourceProcessingStrategy(checkpointStrategyBuilder);
checkpointStrategyBuilder.Validate(Mode); // avoid future exceptions in coreprojection
return(stateHandler);
}
catch (Exception ex)
{
SetFaulted(String.Format("Cannot create a projection state handler.\r\n\r\nHandler type: {0}\r\nQuery:\r\n\r\n{1}\r\n\r\nMessage:\r\n\r\n{2}", HandlerType, Query, ex.Message), ex);
if (stateHandler != null)
{
stateHandler.Dispose();
}
throw;
}
});
//note: set runnign before start as coreProjection.start() can respond with faulted
_state = ManagedProjectionState.Running;
_coreQueue.Publish(createProjectionMessage);
_coreQueue.Publish(new ProjectionMessage.Projections.Management.Start(_id));
}
private void Start(Action completed)
{
if (!Enabled)
{
throw new InvalidOperationException("Projection is disabled");
}
_onStopped = _onStarted = () =>
{
_onStopped = null;
_onStarted = null;
if (completed != null)
{
completed();
}
};
_state = ManagedProjectionState.Starting;
_coreQueue.Publish(new CoreProjectionManagementMessage.Start(Id));
}
private void LoadCompleted(ClientMessage.ReadStreamEventsBackwardCompleted completed)
{
if (completed.Result == RangeReadResult.Success && completed.Events.Length == 1)
{
byte[] state = completed.Events[0].Event.Data;
LoadPersistedState(state.ParseJson <PersistedState>());
//TODO: encapsulate this into managed projection
_state = ManagedProjectionState.Stopped;
StartIfEnabled();
return;
}
_state = ManagedProjectionState.Creating;
_logger.Trace(
"Projection manager did not find any projection configuration records in the {0} stream. Projection stays in CREATING state",
completed.EventStreamId);
}
private void WriteCompleted(
ClientMessage.WriteEventsCompleted message, ManagedProjectionState completedState, Action completed,
string eventStreamId)
{
if (_state != ManagedProjectionState.Writing)
{
_logger.Error("Projection definition write completed in non writing state. ({0})", _name);
}
if (message.Result == OperationResult.Success)
{
_logger.Info("'{0}' projection source has been written", _name);
var writtenEventNumber = message.FirstEventNumber;
if (writtenEventNumber != (_persistedState.Version ?? writtenEventNumber))
{
throw new Exception("Projection version and event number mismatch");
}
_lastWrittenVersion = (_persistedState.Version ?? writtenEventNumber);
_state = completedState;
if (completed != null)
{
completed();
}
return;
}
_logger.Info(
"Projection '{0}' source has not been written to {1}. Error: {2}", _name, eventStreamId,
Enum.GetName(typeof(OperationResult), message.Result));
if (message.Result == OperationResult.CommitTimeout || message.Result == OperationResult.ForwardTimeout ||
message.Result == OperationResult.PrepareTimeout ||
message.Result == OperationResult.WrongExpectedVersion)
{
_logger.Info("Retrying write projection source for {0}", _name);
BeginWrite(completed);
}
else
{
throw new NotSupportedException("Unsupported error code received");
}
}
private void BeginWrite(Action completed)
{
if (Mode == ProjectionMode.Transient)
{
//TODO: move to common completion procedure
_lastWrittenVersion = _persistedState.Version ?? -1;
completed();
return;
}
var oldState = _state;
_state = ManagedProjectionState.Writing;
var managedProjectionSerializedState = _persistedState.ToJsonBytes();
var eventStreamId = "$projections-" + _name;
var corrId = Guid.NewGuid();
_writeDispatcher.Publish(
new ClientMessage.WriteEvents(
corrId, corrId, _writeDispatcher.Envelope, true, eventStreamId, ExpectedVersion.Any,
new Event(Guid.NewGuid(), "$ProjectionUpdated", true, managedProjectionSerializedState, Empty.ByteArray),
SystemAccount.Principal),
m => WriteCompleted(m, oldState, completed, eventStreamId));
}
public void Handle(CoreProjectionManagementMessage.Stopped message)
{
_state = message.Completed ? ManagedProjectionState.Completed : ManagedProjectionState.Stopped;
OnStoppedOrFaulted();
}
private void SetFaulted(string reason, Exception ex = null)
{
if (ex != null)
_logger.ErrorException(ex, "The '{0}' projection faulted due to '{1}'", _name, reason);
else
_logger.Error("The '{0}' projection faulted due to '{1}'", _name, reason);
_state = ManagedProjectionState.Faulted;
_faultedReason = reason;
}
private void Stop(Action completed)
{
switch (_state)
{
case ManagedProjectionState.Stopped:
case ManagedProjectionState.Faulted:
if (completed != null) completed();
return;
case ManagedProjectionState.Loading:
case ManagedProjectionState.Creating:
throw new InvalidOperationException(
string.Format(
"Cannot stop a projection in the '{0}' state",
Enum.GetName(typeof (ManagedProjectionState), _state)));
case ManagedProjectionState.Stopping:
_stopCompleted += completed;
return;
case ManagedProjectionState.Running:
case ManagedProjectionState.Starting:
_state = ManagedProjectionState.Stopping;
_stopCompleted = completed;
_coreQueue.Publish(new CoreProjectionManagementMessage.Stop(_id));
break;
default:
throw new NotSupportedException();
}
}
public void Handle(CoreProjectionManagementMessage.Prepared message)
{
_state = ManagedProjectionState.Prepared;
_persistedState.SourceDefintion = message.SourceDefintion;
OnPrepared();
}
private void BeginCreateAndPrepare(
ProjectionStateHandlerFactory handlerFactory, ProjectionConfig config,
Action onPrepared)
{
_onPrepared = onPrepared;
if (handlerFactory == null) throw new ArgumentNullException("handlerFactory");
if (config == null) throw new ArgumentNullException("config");
//TODO: which states are allowed here?
if (_state >= ManagedProjectionState.Preparing)
throw new InvalidOperationException("Already preparing or has been prepared");
//TODO: load configuration from the definition
var createProjectionMessage =
new CoreProjectionManagementMessage.CreateAndPrepare(
new PublishEnvelope(_inputQueue), _id, _name, config, delegate
{
// this delegate runs in the context of a projection core thread
// TODO: move this code to the projection core service as we may be in different processes in the future
IProjectionStateHandler stateHandler = null;
try
{
stateHandler = handlerFactory.Create(HandlerType, Query, Console.WriteLine);
var checkpointStrategyBuilder = new CheckpointStrategy.Builder();
stateHandler.ConfigureSourceProcessingStrategy(checkpointStrategyBuilder);
checkpointStrategyBuilder.Validate(Mode); // avoid future exceptions in coreprojection
return stateHandler;
}
catch (Exception ex)
{
SetFaulted(
string.Format(
"Cannot create a projection state handler.\r\n\r\nHandler type: {0}\r\nQuery:\r\n\r\n{1}\r\n\r\nMessage:\r\n\r\n{2}",
HandlerType, Query, ex.Message), ex);
if (stateHandler != null)
stateHandler.Dispose();
throw;
}
});
//note: set runnign before start as coreProjection.start() can respond with faulted
_state = ManagedProjectionState.Preparing;
_coreQueue.Publish(createProjectionMessage);
}
private void BeginCreateAndPrepare(
ProjectionStateHandlerFactory handlerFactory, ProjectionConfig config, Action onPrepared)
{
_onPrepared = _onStopped = () =>
{
_onStopped = null;
_onPrepared = null;
if (onPrepared != null)
onPrepared();
};
if (handlerFactory == null) throw new ArgumentNullException("handlerFactory");
if (config == null) throw new ArgumentNullException("config");
//TODO: which states are allowed here?
if (_state >= ManagedProjectionState.Preparing)
{
DisposeCoreProjection();
_state = ManagedProjectionState.Loaded;
}
//TODO: load configuration from the definition
Func<IProjectionStateHandler> stateHandlerFactory = delegate
{
// this delegate runs in the context of a projection core thread
// TODO: move this code to the projection core service as we may be in different processes in the future
IProjectionStateHandler stateHandler = null;
try
{
stateHandler = handlerFactory.Create(
HandlerType, Query, logger: s => _logger.Trace(s),
cancelCallbackFactory:
_timeoutScheduler == null
? (Action<int, Action>) null
: _timeoutScheduler.Schedule);
return stateHandler;
}
catch (Exception ex)
{
SetFaulted(
string.Format(
"Cannot create a projection state handler.\r\n\r\nHandler type: {0}\r\nQuery:\r\n\r\n{1}\r\n\r\nMessage:\r\n\r\n{2}",
HandlerType, Query, ex.Message), ex);
if (stateHandler != null)
stateHandler.Dispose();
throw;
}
};
var createProjectionMessage = _isSlave ?
(Message) new CoreProjectionManagementMessage.CreateAndPrepareSlave(
new PublishEnvelope(_inputQueue), Id, _name,
new ProjectionVersion(_projectionId, _persistedState.Epoch ?? 0, _persistedState.Version ?? 0),
config, _slaveResultsPublisher, _slaveMasterCorrelationId, stateHandlerFactory) :
new CoreProjectionManagementMessage.CreateAndPrepare(
new PublishEnvelope(_inputQueue), Id, _name,
new ProjectionVersion(_projectionId, _persistedState.Epoch ?? 0, _persistedState.Version ?? 0),
config, HandlerType, Query, stateHandlerFactory);
//note: set runnign before start as coreProjection.start() can respond with faulted
_state = ManagedProjectionState.Preparing;
_coreQueue.Publish(createProjectionMessage);
}
public void Handle(CoreProjectionManagementMessage.Started message)
{
_state = ManagedProjectionState.Running;
if (_onStarted != null)
{
var action = _onStarted;
_onStarted = null;
action();
}
}
internal void SetState(ManagedProjectionState value)
{
_state = value;
switch (value)
{
case ManagedProjectionState.Aborted:
_stateHandler = new AbortedState(this);
break;
case ManagedProjectionState.Aborting:
_stateHandler = new AbortingState(this);
break;
case ManagedProjectionState.Completed:
_stateHandler = new CompletedState(this);
break;
case ManagedProjectionState.Creating:
case ManagedProjectionState.Loading:
case ManagedProjectionState.Loaded:
_stateHandler = new CreatingLoadingLoadedState(this);
break;
case ManagedProjectionState.Faulted:
_stateHandler = new FaultedState(this);
break;
case ManagedProjectionState.LoadingStopped:
_stateHandler = new LoadingStateState(this);
break;
case ManagedProjectionState.Prepared:
_stateHandler = new PreparedState(this);
break;
case ManagedProjectionState.Preparing:
_stateHandler = new PreparingState(this);
break;
case ManagedProjectionState.Running:
_stateHandler = new RunningState(this);
break;
case ManagedProjectionState.Starting:
_stateHandler = new StartingState(this);
break;
case ManagedProjectionState.Stopped:
_stateHandler = new StoppedState(this);
break;
case ManagedProjectionState.Stopping:
_stateHandler = new StoppingState(this);
break;
case ManagedProjectionState.Deleting:
_stateHandler = new DeletingState(this);
break;
default:
throw new Exception();
}
}
private void LoadStopped(Action onLoaded)
{
_onStopped = onLoaded;
_state = ManagedProjectionState.LoadingState;
_coreQueue.Publish(new CoreProjectionManagementMessage.LoadStopped(Id));
}
private void StartNew(Action completed)
{
_state = ManagedProjectionState.Stopped;
StartIfEnabled();
if (completed != null) completed();
}
private void Start(IPublisher coreOutput, ProjectionStateHandlerFactory handlerFactory, ProjectionConfig config)
{
if (coreOutput == null) throw new ArgumentNullException("coreOutput");
if (handlerFactory == null) throw new ArgumentNullException("handlerFactory");
if (config == null) throw new ArgumentNullException("config");
if (_coreProjection != null)
throw new InvalidOperationException("CoreProjection has been already created");
IProjectionStateHandler stateHandler = null;
try
{
stateHandler = handlerFactory.Create(HandlerType, Query, Console.WriteLine);
var checkpointStrategyBuilder = new CheckpointStrategy.Builder();
stateHandler.ConfigureSourceProcessingStrategy(checkpointStrategyBuilder);
checkpointStrategyBuilder.Validate(this.Mode); // avoid future exceptions in coreprojection
// constructor can fail if wrong source defintion
//TODO: revise it
_coreProjection = new CoreProjection(_name, _id, coreOutput, stateHandler, config, _logger);
}
catch (Exception ex)
{
SetFaulted(
String.Format(
"Cannot create a projection state handler.\r\n\r\nHandler type: {0}\r\nQuery:\r\n\r\n{1}\r\n\r\nMessage:\r\n\r\n{2}",
HandlerType, Query, ex.Message), ex);
if (stateHandler != null)
stateHandler.Dispose();
return;
}
//TODO: load configuration from the definition
_state = ManagedProjectionState.Running;
//note: set runnign before start as coreProjection.start() can respond with faulted
_coreProjection.Start();
}
private void Start(ProjectionStateHandlerFactory handlerFactory, ProjectionConfig config)
{
if (handlerFactory == null) throw new ArgumentNullException("handlerFactory");
if (config == null) throw new ArgumentNullException("config");
if (_state == ManagedProjectionState.Running)
throw new InvalidOperationException("Already started");
//TODO: load configuration from the definition
var createProjectionMessage = new ProjectionMessage.CoreService.Management.Create(new PublishEnvelope(_inputQueue), _id, _name, config, delegate
{
IProjectionStateHandler stateHandler = null;
try
{
stateHandler = handlerFactory.Create(this.HandlerType, this.Query, Console.WriteLine);
var checkpointStrategyBuilder = new CheckpointStrategy.Builder();
stateHandler.ConfigureSourceProcessingStrategy(checkpointStrategyBuilder);
checkpointStrategyBuilder.Validate(Mode); // avoid future exceptions in coreprojection
return stateHandler;
}
catch (Exception ex)
{
SetFaulted(String.Format("Cannot create a projection state handler.\r\n\r\nHandler type: {0}\r\nQuery:\r\n\r\n{1}\r\n\r\nMessage:\r\n\r\n{2}", HandlerType, Query, ex.Message), ex);
if (stateHandler != null)
stateHandler.Dispose();
throw;
}
});
//note: set runnign before start as coreProjection.start() can respond with faulted
_state = ManagedProjectionState.Running;
_coreQueue.Publish(createProjectionMessage);
_coreQueue.Publish(new ProjectionMessage.Projections.Management.Start(_id));
}
public void InitializeExisting(string name)
{
_state = ManagedProjectionState.Loading;
BeginLoad(name);
}
public void Handle(CoreProjectionManagementMessage.Prepared message)
{
_state = ManagedProjectionState.Prepared;
_persistedState.SourceDefinition = message.SourceDefinition;
OnPrepared();
}
private void Start(Action completed)
{
if (!Enabled)
throw new InvalidOperationException("Projection is disabled");
_onStopped = _onStarted = () =>
{
_onStopped = null;
_onStarted = null;
if (completed != null)
completed();
};
_state = ManagedProjectionState.Starting;
_coreQueue.Publish(new CoreProjectionManagementMessage.Start(Id));
}
private void BeginCreateAndPrepare(
ProjectionStateHandlerFactory handlerFactory, ProjectionConfig config, Action onPrepared)
{
_onPrepared = _onStopped = () =>
{
_onStopped = null;
_onPrepared = null;
if (onPrepared != null)
{
onPrepared();
}
};
if (handlerFactory == null)
{
throw new ArgumentNullException("handlerFactory");
}
if (config == null)
{
throw new ArgumentNullException("config");
}
//TODO: which states are allowed here?
if (_state >= ManagedProjectionState.Preparing)
{
DisposeCoreProjection();
_state = ManagedProjectionState.Loaded;
}
//TODO: load configuration from the definition
Func <IProjectionStateHandler> stateHandlerFactory = delegate
{
// this delegate runs in the context of a projection core thread
// TODO: move this code to the projection core service as we may be in different processes in the future
IProjectionStateHandler stateHandler = null;
try
{
stateHandler = handlerFactory.Create(
HandlerType, Query, logger: s => _logger.Trace(s),
cancelCallbackFactory:
_timeoutScheduler == null
? (Action <int, Action>)null
: _timeoutScheduler.Schedule);
return(stateHandler);
}
catch (Exception ex)
{
SetFaulted(
string.Format(
"Cannot create a projection state handler.\r\n\r\nHandler type: {0}\r\nQuery:\r\n\r\n{1}\r\n\r\nMessage:\r\n\r\n{2}",
HandlerType, Query, ex.Message), ex);
if (stateHandler != null)
{
stateHandler.Dispose();
}
throw;
}
};
var createProjectionMessage = _isSlave ?
(Message) new CoreProjectionManagementMessage.CreateAndPrepareSlave(
new PublishEnvelope(_inputQueue), Id, _name,
new ProjectionVersion(_projectionId, _persistedState.Epoch ?? 0, _persistedState.Version ?? 0),
config, _slaveResultsPublisher, _slaveMasterCorrelationId, stateHandlerFactory) :
new CoreProjectionManagementMessage.CreateAndPrepare(
new PublishEnvelope(_inputQueue), Id, _name,
new ProjectionVersion(_projectionId, _persistedState.Epoch ?? 0, _persistedState.Version ?? 0),
config, HandlerType, Query, stateHandlerFactory);
//note: set runnign before start as coreProjection.start() can respond with faulted
_state = ManagedProjectionState.Preparing;
_coreQueue.Publish(createProjectionMessage);
}
private void LoadStopped(Action onLoaded)
{
_onStopped = onLoaded;
_state = ManagedProjectionState.LoadingState;
_coreQueue.Publish(new CoreProjectionManagementMessage.LoadStopped(Id));
}
internal void SetState(ManagedProjectionState value)
{
// _logger.Trace("MP: {0} {1} => {2}", _name, _state, value);
_state = value;
switch (value)
{
case ManagedProjectionState.Aborted:
_stateHandler = new AbortedState(this);
break;
case ManagedProjectionState.Aborting:
_stateHandler = new AbortingState(this);
break;
case ManagedProjectionState.Completed:
_stateHandler = new CompletedState(this);
break;
case ManagedProjectionState.Creating:
case ManagedProjectionState.Loading:
case ManagedProjectionState.Loaded:
_stateHandler = new CreatingLoadingLoadedState(this);
break;
case ManagedProjectionState.Faulted:
_stateHandler = new FaultedState(this);
break;
case ManagedProjectionState.LoadingStopped:
_stateHandler = new LoadingStateState(this);
break;
case ManagedProjectionState.Prepared:
_stateHandler = new PreparedState(this);
break;
case ManagedProjectionState.Preparing:
_stateHandler = new PreparingState(this);
break;
case ManagedProjectionState.Running:
_stateHandler = new RunningState(this);
break;
case ManagedProjectionState.Starting:
_stateHandler = new StartingState(this);
break;
case ManagedProjectionState.Stopped:
_stateHandler = new StoppedState(this);
break;
case ManagedProjectionState.Stopping:
_stateHandler = new StoppingState(this);
break;
default:
throw new Exception();
}
}
private void BeginCreatePrepared(ProjectionConfig config, Action onPrepared)
{
_onPrepared = onPrepared;
if (config == null) throw new ArgumentNullException("config");
//TODO: which states are allowed here?
if (_state >= ManagedProjectionState.Preparing)
{
DisposeCoreProjection();
_state = ManagedProjectionState.Loaded;
}
//TODO: load configuration from the definition
if (_persistedState.SourceDefinition == null)
throw new Exception(
"The projection cannot be loaded as stopped as it was stored in the old format. Update the projection query text to force prepare");
var createProjectionMessage =
new CoreProjectionManagementMessage.CreatePrepared(
new PublishEnvelope(_inputQueue), Id, _name,
new ProjectionVersion(_projectionId, _persistedState.Epoch ?? 0, _persistedState.Version ?? 1),
config, _persistedState.SourceDefinition, HandlerType, Query);
//note: set running before start as coreProjection.start() can respond with faulted
_state = ManagedProjectionState.Preparing;
_coreQueue.Publish(createProjectionMessage);
}
public void Handle(CoreProjectionManagementMessage.Stopped message)
{
_state = message.Completed ? ManagedProjectionState.Completed : ManagedProjectionState.Stopped;
OnStoppedOrFaulted();
}
public void Handle(CoreProjectionManagementMessage.Stopped message)
{
_state = ManagedProjectionState.Stopped;
DisposeCoreProjection();
var stopCompleted = _stopCompleted;
_stopCompleted = null;
if (stopCompleted != null) stopCompleted();
}
public void Handle(CoreProjectionManagementMessage.Prepared message)
{
_persistedState.SourceDefinition = message.SourceDefinition;
if (_state == ManagedProjectionState.Preparing)
{
_state = ManagedProjectionState.Prepared;
OnPrepared();
}
else
{
_logger.Trace("Received prepared without being prepared");
}
}
public void InitializeExisting(string name)
{
_state = ManagedProjectionState.Loading;
BeginLoad(name);
}
private void LoadCompleted(ClientMessage.ReadStreamEventsBackwardCompleted completed)
{
if (completed.Result == ReadStreamResult.Success && completed.Events.Length == 1)
{
byte[] state = completed.Events[0].Event.Data;
var persistedState = state.ParseJson<PersistedState>();
_lastWrittenVersion = completed.Events[0].Event.EventNumber;
FixUpOldFormat(completed, persistedState);
FixupOldProjectionModes(persistedState);
FixUpOldProjectionRunAs(persistedState);
LoadPersistedState(persistedState);
//TODO: encapsulate this into managed projection
_state = ManagedProjectionState.Loaded;
if (Enabled && _enabledToRun)
{
if (Mode >= ProjectionMode.Continuous)
Prepare(() => Start(() => { }));
}
else
CreatePrepared(() => LoadStopped(() => { }));
return;
}
_state = ManagedProjectionState.Creating;
_logger.Trace(
"Projection manager did not find any projection configuration records in the {0} stream. Projection stays in CREATING state",
completed.EventStreamId);
}
private void LoadCompleted(ClientMessage.ReadStreamEventsBackwardCompleted completed)
{
if (completed.Result == RangeReadResult.Success && completed.Events.Length == 1)
{
byte[] state = completed.Events[0].Event.Data;
LoadPersistedState(state.ParseJson<PersistedState>());
//TODO: encapsulate this into managed projection
_state = ManagedProjectionState.Stopped;
if (Enabled)
Prepare(() => Start(() => { }));
return;
}
_state = ManagedProjectionState.Creating;
_logger.Trace(
"Projection manager did not find any projection configuration records in the {0} stream. Projection stays in CREATING state",
completed.EventStreamId);
}
private void BeginWrite(Action completed)
{
if (Mode == ProjectionMode.Transient)
{
//TODO: move to common completion procedure
_lastWrittenVersion = _persistedState.Version ?? -1;
completed();
return;
}
var oldState = _state;
_state = ManagedProjectionState.Writing;
var managedProjectionSerializedState = _persistedState.ToJsonBytes();
var eventStreamId = "$projections-" + _name;
var corrId = Guid.NewGuid();
_writeDispatcher.Publish(
new ClientMessage.WriteEvents(
corrId, corrId, _writeDispatcher.Envelope, true, eventStreamId, ExpectedVersion.Any,
new Event(Guid.NewGuid(), "$ProjectionUpdated", true, managedProjectionSerializedState, Empty.ByteArray),
SystemAccount.Principal),
m => WriteCompleted(m, oldState, completed, eventStreamId));
}
private void Start(Action onStarted)
{
if (!Enabled)
throw new InvalidOperationException("Projection is disabled");
_onStarted = onStarted;
_state = ManagedProjectionState.Starting;
_coreQueue.Publish(new CoreProjectionManagementMessage.Start(_id));
}
private void WriteCompleted(
ClientMessage.WriteEventsCompleted message, ManagedProjectionState completedState, Action completed,
string eventStreamId)
{
if (_state != ManagedProjectionState.Writing)
{
_logger.Error("Projection definition write completed in non writing state. ({0})", _name);
}
if (message.Result == OperationResult.Success)
{
_logger.Info("'{0}' projection source has been written", _name);
var writtenEventNumber = message.FirstEventNumber;
if (writtenEventNumber != (_persistedState.Version ?? writtenEventNumber))
throw new Exception("Projection version and event number mismatch");
_lastWrittenVersion = (_persistedState.Version ?? writtenEventNumber);
_state = completedState;
if (completed != null) completed();
return;
}
_logger.Info(
"Projection '{0}' source has not been written to {1}. Error: {2}", _name, eventStreamId,
Enum.GetName(typeof (OperationResult), message.Result));
if (message.Result == OperationResult.CommitTimeout || message.Result == OperationResult.ForwardTimeout
|| message.Result == OperationResult.PrepareTimeout
|| message.Result == OperationResult.WrongExpectedVersion)
{
_logger.Info("Retrying write projection source for {0}", _name);
BeginWrite(completed);
}
else
throw new NotSupportedException("Unsupported error code received");
}
public void Handle(CoreProjectionManagementMessage.Stopped message)
{
_state = ManagedProjectionState.Stopped;
FireStoppedOrFaulted();
}
internal void SetState(ManagedProjectionState value)
{
_state = value;
switch (value)
{
case ManagedProjectionState.Aborted:
_stateHandler = new AbortedState(this);
break;
case ManagedProjectionState.Aborting:
_stateHandler = new AbortingState(this);
break;
case ManagedProjectionState.Completed:
_stateHandler = new CompletedState(this);
break;
case ManagedProjectionState.Creating:
case ManagedProjectionState.Loading:
case ManagedProjectionState.Loaded:
_stateHandler = new CreatingLoadingLoadedState(this);
break;
case ManagedProjectionState.Faulted:
_stateHandler = new FaultedState(this);
break;
case ManagedProjectionState.LoadingStopped:
_stateHandler = new LoadingStateState(this);
break;
case ManagedProjectionState.Prepared:
_stateHandler = new PreparedState(this);
break;
case ManagedProjectionState.Preparing:
_stateHandler = new PreparingState(this);
break;
case ManagedProjectionState.Running:
_stateHandler = new RunningState(this);
break;
case ManagedProjectionState.Starting:
_stateHandler = new StartingState(this);
break;
case ManagedProjectionState.Stopped:
_stateHandler = new StoppedState(this);
break;
case ManagedProjectionState.Stopping:
_stateHandler = new StoppingState(this);
break;
case ManagedProjectionState.Deleting:
_stateHandler = new DeletingState(this);
break;
default:
throw new Exception();
}
}
