/// <inheritdoc/>
protected override async Task ProcessAsync(CancellationToken cancellationToken)
{
if (!this.Activity.Metadata.TryGetValue(V1WorkflowActivityMetadata.Subflow, out var workflowInstanceId))
{
workflowInstanceId = await this.Context.Workflow.StartSubflowAsync($"{this.Subflow.WorkflowId}:{this.Subflow.Version}", this.Activity.Input, cancellationToken);
this.Activity.Metadata.Add(V1WorkflowActivityMetadata.Subflow, workflowInstanceId);
await this.Context.Workflow.SetActivityMetadataAsync(this.Activity, cancellationToken);
}
switch (this.Subflow.InvocationMode)
{
case InvocationMode.Asynchronous:
await this.OnNextAsync(new V1WorkflowActivityCompletedIntegrationEvent(this.Activity.Id, this.Activity.Input), this.CancellationTokenSource.Token);
await this.OnCompletedAsync(this.CancellationTokenSource.Token);
break;
case InvocationMode.Synchronous:
var eventDefinition = new EventDefinition()
{
Kind = EventKind.Consumed,
Name = "onSubflowExecuted",
Source = CloudEvents.Source.ToString(),
Type = CloudEvents.TypeOf(typeof(V1WorkflowInstanceExecutedIntegrationEvent), typeof(V1WorkflowInstance)),
Correlations = new()
{
new() { ContextAttributeName = nameof(CloudEvent.Subject).ToLower(), ContextAttributeValue = workflowInstanceId }
}
};
var e = await this.Context.Workflow.ConsumeOrBeginCorrelateEventAsync(eventDefinition, cancellationToken);
if (e != null)
{
await this.OnEventAsync(e);
return;
}
this.Subscription = this.IntegrationEventBus.InboundStream
.Where(e => e.Subject == workflowInstanceId && e.Source?.ToString() == eventDefinition.Source && e.Type == eventDefinition.Type)
.SubscribeAsync(this.OnEventAsync);
if (this.Options.Correlation.Timeout.HasValue)
{
this.IdleTimer = new Timer(async state => await this.OnIdleTimerExpiredAsync(state, cancellationToken), null, this.Options.Correlation.Timeout.Value, this.Options.Correlation.Timeout.Value);
}
break;
default:
throw new NotSupportedException($"The specified {nameof(InvocationMode)} '{this.Subflow.InvocationMode}' is not supported");
}
}
/// <summary>
/// Publishes a <see cref="CloudEvent"/> for the specified <see cref="IDomainEvent"/>
/// </summary>
/// <param name="e">The <see cref="IDomainEvent"/> to publish a new <see cref="CloudEvent"/> for</param>
/// <param name="cancellationToken">A <see cref="CancellationToken"/></param>
/// <returns>A new awaitable <see cref="Task"/></returns>
protected virtual async Task PublishIntegrationEventAsync <TEvent>(TEvent e, CancellationToken cancellationToken)
where TEvent : class, IDomainEvent
{
if (!e.GetType().TryGetCustomAttribute(out DataTransferObjectTypeAttribute dataTransferObjectTypeAttribute))
{
return;
}
var integrationEvent = (V1IntegrationEvent)this.Mapper.Map(e, e.GetType(), dataTransferObjectTypeAttribute.Type);
var aggregateType = e.GetType().GetGenericType(typeof(DomainEvent <,>)).GetGenericArguments()[0];
var cloudEvent = new CloudEvent()
{
Id = Guid.NewGuid().ToString(),
Source = CloudEvents.Source,
Type = CloudEvents.TypeOf(typeof(TEvent), aggregateType),
Time = e.CreatedAt,
Subject = e.AggregateId.ToString(),
DataSchema = CloudEvents.SchemaOf(typeof(TEvent), aggregateType),
DataContentType = MediaTypeNames.Application.Json,
Data = integrationEvent
};
await this.IntegrationEventBus.PublishAsync(cloudEvent, cancellationToken);
}
