Class RecordingCommandBus

java.lang.Object
org.axonframework.test.fixture.RecordingCommandBus
All Implemented Interfaces:
DescribableComponent, CommandBus, CommandHandlerRegistry<CommandBus>

@Internal public class RecordingCommandBus extends Object implements CommandBus
An CommandBus implementation recording all the commands that are dispatched. The recorded commands can then be used to assert expectations with test cases.
Since:
5.0.0
Author:
Allard Buijze, Mateusz Nowak
  • Constructor Details

    • RecordingCommandBus

      public RecordingCommandBus(@Nonnull CommandBus delegate)
      Creates a new RecordingCommandBus that will record all commands dispatched to the given delegate.
      Parameters:
      delegate - The CommandBus to which commands will be dispatched.
  • Method Details

    • dispatch

      public CompletableFuture<CommandResultMessage> dispatch(@Nonnull CommandMessage command, @Nullable ProcessingContext processingContext)
      Description copied from interface: CommandBus
      Dispatch the given command to the command handler subscribed to the given command's name. The name is typically deferred from the Message.type(), which contains a MessageType.qualifiedName().
      Specified by:
      dispatch in interface CommandBus
      Parameters:
      command - The command to dispatch.
      processingContext - The processing context under which the command is being published (can be null).
      Returns:
      The CompletableFuture providing the result of the command, once finished.
    • subscribe

      public CommandBus subscribe(@Nonnull QualifiedName name, @Nonnull CommandHandler commandHandler)
      Description copied from interface: CommandHandlerRegistry
      Subscribe the given handler for commands of the given name.

      If a subscription already exists for the name, the behavior is undefined. Implementations may throw an exception to refuse duplicate subscription or alternatively decide whether the existing or new handler gets the subscription.

      Specified by:
      subscribe in interface CommandHandlerRegistry<CommandBus>
      Parameters:
      name - The name the given commandHandler can handle.
      commandHandler - The handler instance that handles commands for the given name.
      Returns:
      This registry for fluent interfacing.
    • describeTo

      public void describeTo(@Nonnull ComponentDescriptor descriptor)
      Description copied from interface: DescribableComponent
      Describe the properties of this DescribableComponent with the given descriptor.

      Components should call the appropriate describeProperty methods on the descriptor to register their properties. The descriptor is responsible for determining how these properties are formatted and structured in the final output.

      Best Practices: As a general rule, all relevant fields of a DescribableComponent implementation should be described in this method. However, developers have discretion to include only the fields that make sense in the context. Not every field may be meaningful for description purposes, especially internal implementation details. Furthermore, components might want to expose different information based on their current state. The final decision on what properties to include lies with the person implementing the describeTo method, who should focus on providing information that is useful for understanding the component's configuration and state.

      Example implementation:

       public void describeTo(ComponentDescriptor descriptor) {
           descriptor.describeProperty("name", this.name);
           descriptor.describeProperty("enabled", this.enabled);
           descriptor.describeProperty("configuration", this.configuration); // A nested component
           descriptor.describeProperty("handlers", this.eventHandlers);      // A collection
       }
       
      Specified by:
      describeTo in interface DescribableComponent
      Parameters:
      descriptor - The component descriptor to describe this DescribableComponentn its properties in.
    • recorded

      public Map<CommandMessage,Message> recorded()
      Returns map of all the CommandMessages dispatched, and their corresponding results.
      Returns:
      A map of all the CommandMessages dispatched, and their corresponding results.
    • recordedCommands

      public List<CommandMessage> recordedCommands()
      Returns the commands that have been dispatched to this CommandBus.
      Returns:
      The commands that have been dispatched to this CommandBus
    • resultOf

      @Nullable public Message resultOf(@Nonnull CommandMessage command)
      Returns the result of the given command.
      Parameters:
      command - The command for which the result is returned.
      Returns:
      The result of the given command. May be null if the command has not been dispatched yet.
    • reset

      public RecordingCommandBus reset()
      Resets this recording CommandBus, by removing all recorded CommandMessages.
      Returns:
      This recording CommandBus, for fluent interfacing.