CreateAggregate

Marks a command as one that creates new aggregate instances.

Commands annotated with @CreateAggregate are designated as initialization commands that create new aggregates. These commands are the first commands applied to an aggregate and establish its initial state.

Create commands typically:

• Have no version requirements (target version is 0)

• Cannot be applied to existing aggregates

• Initialize the aggregate's state from scratch

• Publish creation events

Example usage:

@CreateAggregate
data class CreateUserCommand(
    @AggregateId
    val userId: String,
    val email: String,
    val name: String
)

@AggregateRoot
class UserAggregate {

    @OnCommand
    fun create(command: CreateUserCommand): UserCreated {
        // This is the first command for new users
        return UserCreated(command.userId, command.email, command.name)
    }
}

See also