Package net.corda.v5.application.messaging

Interface ExternalMessaging

  • All Implemented Interfaces:
    
public interface ExternalMessaging

    ExternalMessaging allows a flow to communicate with an external system via a predefined named channel.

    The platform will provide an instance of ExternalMessaging to flows via property injection.

    A Flow can send use this API to send messages to any external channel that has been defined as part of the CorDapp ({@see Defining External Messaging Channels}).

    Example usage:

    • Kotlin:
      
class MyFlow : ClientStartableFlow {
   
   lateinit var externalMessaging: ExternalMessaging

   override fun call(requestBody: RestRequestBody): String {
       val myChannelName = "my channel"

       // Send a simple message to my channel
       externalMessaging.send(myChannelName, "hello")

       // Send a simple message with an ID to my channel
       externalMessaging.send(myChannelName,"id-1", "hello")

       return ""
   }
 }
    • Java:
      
class MyFlow implements ClientStartableFlow {

   
   public ExternalMessaging externalMessaging;

   
   public String call(RestRequestBody requestBody) {
       String myChannelName = "my channel";

       // Send a simple message to my channel
       externalMessaging.send(myChannelName, "hello");

       // Send a simple message with an ID to my channel
       externalMessaging.send(myChannelName,"id-1", "hello");

       return "";
   }
}

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      abstract void send(@NotNull() String channelName, @NotNull() String message) Sends a message through a named channel.
      abstract void send(@NotNull() String channelName, @NotNull() String messageId, @NotNull() String message) Sends a message with identifier through a named channel.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

    • Method Detail

      • send

        @Suspendable() abstract void send(@NotNull() String channelName, @NotNull() String message)

        Sends a message through a named channel.

        Parameters:
        channelName - The name of the channel the message should be sent through.
        message - The contents of the message to be sent.

      • send

        @Suspendable() abstract void send(@NotNull() String channelName, @NotNull() String messageId, @NotNull() String message)

        Sends a message with identifier through a named channel.

        Parameters:
        channelName - The name of the channel the message should be sent through.
        messageId - An ID of the message to be sent.
        message - The contents of the message to be sent.