/// <summary>
/// Initializes a new instance of the <see cref="PipelineContext"/> class.
/// </summary>
/// <param name="message">The message.</param>
/// <param name="saga">The saga.</param>
/// <param name="operationResult">The operation result. Null of operation have not finished</param>
public PipelineContext(ISagaMessage message, IAccessibleSaga saga, OperationResult operationResult = null)
{
this.Message = message;
this.AccessibleSaga = saga;
SagaData = NSagaReflection.Get(saga, "SagaData");
OperationResult = operationResult;
}
/// <summary>
/// Deletes the saga instance from the storage
/// </summary>
/// <typeparam name="TSaga">Type of saga</typeparam>
/// <param name="saga">Saga to be deleted</param>
public void Complete <TSaga>(TSaga saga) where TSaga : class, IAccessibleSaga
{
Guard.ArgumentIsNotNull(saga, nameof(saga));
var correlationId = (Guid)NSagaReflection.Get(saga, "CorrelationId");
Complete(correlationId);
}
/// <summary>
/// Persists the instance of saga into the database storage.
///
/// Actually stores SagaData and Headers. All other variables in saga are not persisted
/// </summary>
/// <typeparam name="TSaga">Type of saga</typeparam>
/// <param name="saga">Saga instance</param>
public void Save <TSaga>(TSaga saga) where TSaga : class, IAccessibleSaga
{
Guard.ArgumentIsNotNull(saga, nameof(saga));
var sagaData = NSagaReflection.Get(saga, "SagaData");
var sagaHeaders = (Dictionary <String, String>)NSagaReflection.Get(saga, "Headers");
var correlationId = (Guid)NSagaReflection.Get(saga, "CorrelationId");
var serialisedData = messageSerialiser.Serialise(sagaData);
var dataModel = new SagaData()
{
CorrelationId = correlationId,
BlobData = serialisedData,
};
using (var connection = connectionFactory.CreateOpenConnection())
using (var database = new Database(connection))
using (var transaction = database.GetTransaction())
{
try
{
int updatedRaws = database.Update(dataModel);
if (updatedRaws == 0)
{
// no records were updated - this means no records already exist - need to insert new record
database.Insert(dataModel);
}
// delete all existing headers
database.Delete <SagaHeaders>("WHERE CorrelationId=@0", correlationId);
// and insert updated ones
foreach (var header in sagaHeaders)
{
var storedHeader = new SagaHeaders()
{
CorrelationId = correlationId,
Key = header.Key,
Value = header.Value,
};
database.Insert(storedHeader);
}
transaction.Complete();
}
catch (Exception)
{
transaction.Dispose();
throw;
}
}
}
/// <summary>
/// Persists the instance of saga into the database storage.
/// Actually stores SagaData and Headers. All other variables in saga are not persisted
/// </summary>
/// <typeparam name="TSaga">Type of saga</typeparam>
/// <param name="saga">Saga instance</param>
public void Save <TSaga>(TSaga saga) where TSaga : class, IAccessibleSaga
{
var sagaData = NSagaReflection.Get(saga, "SagaData");
var correlationId = (Guid)NSagaReflection.Get(saga, "CorrelationId");
var headers = (Dictionary <String, String>)NSagaReflection.Get(saga, "Headers");
var serialisedData = messageSerialiser.Serialise(sagaData);
var serialisedHeaders = messageSerialiser.Serialise(headers);
DataDictionary[correlationId] = serialisedData;
HeadersDictionary[correlationId] = serialisedHeaders;
}
/// <summary>
/// Persists the instance of saga into the database storage.
///
/// Actually stores SagaData and Headers. All other variables in saga are not persisted
/// </summary>
/// <typeparam name="TSaga">Type of saga</typeparam>
/// <param name="saga">Saga instance</param>
public void Save <TSaga>(TSaga saga) where TSaga : class, IAccessibleSaga
{
Guard.ArgumentIsNotNull(saga, nameof(saga));
var sagaData = NSagaReflection.Get(saga, "SagaData");
var sagaHeaders = saga.Headers;
var correlationId = saga.CorrelationId;
var serialisedData = messageSerialiser.Serialise(sagaData);
var dataModel = new SagaData()
{
CorrelationId = correlationId,
BlobData = serialisedData,
};
using (var transaction = database.BeginTransaction())
{
try
{
int updatedRaws = database.Update(dataModel);
if (updatedRaws == 0)
{
// no records were updated - this means no records already exist - need to insert new record
database.Insert(dataModel);
}
// delete all existing headers
database.DeleteById <SagaHeaders>(correlationId);
// and insert updated ones
foreach (var header in sagaHeaders)
{
var storedHeader = new SagaHeaders()
{
CorrelationId = correlationId,
Key = header.Key,
Value = header.Value,
};
database.Insert(storedHeader);
}
transaction.CommitTransaction();
}
catch (Exception ex)
{
transaction.RollbackTransaction();
throw;
}
}
}
/// <summary>
/// Consumes the specified initiating message and creates a new instance of the correlating saga.
/// <para>Saga is not persisted if operation have failed</para>
/// </summary>
/// <param name="initiatingMessage">The initiating message.</param>
/// <returns>
/// Result of the operation
/// </returns>
/// <exception cref="System.ArgumentException"></exception>
public OperationResult Consume(IInitiatingSagaMessage initiatingMessage)
{
Guard.CheckSagaMessage(initiatingMessage, nameof(initiatingMessage));
var resolvedSaga = sagaFactory.ResolveSagaInititatedBy(initiatingMessage);
var sagaType = resolvedSaga.GetType();
// try to find sagas that already exist
var existingSaga = NSagaReflection.InvokeGenericMethod(sagaRepository, "Find", sagaType, initiatingMessage.CorrelationId);
if (existingSaga != null)
{
throw new ArgumentException($"Trying to initiate the same saga twice. {initiatingMessage.GetType().Name} is Initiating Message, but saga of type {sagaType.Name} with CorrelationId {initiatingMessage.CorrelationId} already exists");
}
// now create an instance of saga and persist the data
var saga = sagaFactory.ResolveSaga(sagaType);
NSagaReflection.Set(saga, "CorrelationId", initiatingMessage.CorrelationId);
// if SagaData is null - create an instance of the object and assign to saga
var sagaData = NSagaReflection.Get(saga, "SagaData");
if (sagaData == null)
{
var sagaDataType = NSagaReflection.GetInterfaceGenericType(saga, typeof(ISaga <>));
var newSagaData = Activator.CreateInstance(sagaDataType);
NSagaReflection.Set(saga, "SagaData", newSagaData);
}
var sagaHeaders = NSagaReflection.Get(saga, "Headers");
if (sagaHeaders == null)
{
NSagaReflection.Set(saga, "Headers", new Dictionary <String, String>());
}
pipelineHook.BeforeInitialisation(new PipelineContext(initiatingMessage, (IAccessibleSaga)saga));
var errors = (OperationResult)NSagaReflection.InvokeMethod(saga, "Initiate", initiatingMessage);
pipelineHook.AfterInitialisation(new PipelineContext(initiatingMessage, (IAccessibleSaga)saga, errors));
if (errors.IsSuccessful)
{
sagaRepository.Save(saga);
pipelineHook.AfterSave(new PipelineContext(initiatingMessage, (IAccessibleSaga)saga, errors));
}
return(errors);
}
/// <summary>
/// Deletes the saga instance from the storage
/// </summary>
/// <typeparam name="TSaga">Type of saga</typeparam>
/// <param name="saga">Saga to be deleted</param>
public void Complete <TSaga>(TSaga saga) where TSaga : class, IAccessibleSaga
{
var correlationId = (Guid)NSagaReflection.Get(saga, "CorrelationId");
Complete(correlationId);
}