Outbox

The outbox is responsible for adding messages to the storage and then adding at least once to the transport.

builder.Services.AddTransactionalBox(x =>
{
    x.AddOutbox(
        storage => ...,
        transport => ...,
        settings => ...,
        assembly => ...
    );
},
settings => settings.ServiceId = "ServiceName");

Outbox Message

info

Outbox message class name must be unique per service.

public class CreateCustomerCommandMessage : OutboxMessage
{
    public Guid Id { get; init; }

    public string FirstName { get; init; }

    public string LastName { get; init; }

    public int Age { get; init; }
}

Outbox Definition

info

You do not need to define a outbox definition for each message.
By default, the message will be published because receiver is not indicated.

internal class CreateCustomerCommandMessageDefinition : OutboxDefinition<CreateCustomerCommandMessage>
{
    public CreateCustomerCommandMessageDefinition() 
    {
        Receiver = "Customers";
    }
}

Adding a message to the outbox

// Add in the same transaction the result of the business operation and message to outbox

await outbox.Add(message);

// Commit transaction

// After transaction is successfully commited, execute the following method
await outbox.TransactionCommited();

Storage

Options

In Memory (Default)

Entity Framework Core (Relational)

Transport

Options

In Memory (Default)

Apache Kafka

Settings

AddMessagesToTransportSettings

Name	Type	Default Value	Description
MaxBatchSize	int	5000	Maximum number of processing messages per job.
LockTimeout	TimeSpan	10 seconds	Time to live for message blocking.

CleanUpOutboxSettings

Name	Type	Default Value	Description
MaxBatchSize	int	10000	Maximum number of messages to clean up per job.
IsEnabled	bool	true	Value responsible for whether the cleaning process is enabled.

ConfigureSerialization

Name	Extension
System.Text.Json (Default)	UseSystemTextJson()

ConfigureCompression

Name	Extension
No compression (Default)	UseNoCompression()
Brotli	UseBrotli()
GZip	UseGZip()