03. Module: Messaging

Quick Start

Can be included as a dependency:

<dependency>
    <groupId>de.fraunhofer.ids.messaging</groupId>
    <artifactId>messaging</artifactId>
    <version>IDS_MESSAGING_SERVICES_VERSION</version>
</dependency>

Theoretical Background

• All functionalities for sending and receiving IDS-Messages independent of specific infrastructure components.
• Provides the idsHttpService, which can be used to send IDS-Messages to arbitrary endpoints, but the specific message-types itself must be built individually.
• Contains the core-module as dependency and is included by the infrastructure-modules as dependency.
• The individual infrastructure-modules, in turn, provide pre-built functionalities so that the specific message-types do not have to be built individually and the idsHttpService doesn't need to be used for them to send messages.

Scope of Functionality

• Specifies default endpoints for incoming IDS-Messages (/api/ids/data, /api/ids/infrastructure)
• Endpoints can be changed at runtime
• Checks if infomodel-version of incoming message is supported by Connector and Core-DAT-Check
• Provides interface for additional filters for incoming messages
• Provides interface for MessageHandler to be implemented by the Connector for specific message types
• IdsHttpService as a way to send arbitrary IDS-Messages without specific Component-Context
• Set individual Timeouts for connection & call at runtime
• Standard-Response classes (BodyResponse, ErrorResponse)

Handling incoming Messages

To handle IDS Multipart messages, MessageHandlers have to be created. The messaging services provide two types of message handlers: MessageHandler and MessageAndClaimsHandler.

A MessageHandler, gets the IDS message header as an infomodel Message object and the payload as an instance of MessagePayload.

@SupportedMessageType(RequestMessageImpl.class)
public class RequestMessageHandler implements MessageHandler<RequestMessageImpl> {
    @Override
    public MessageResponse handleMessage( final RequestMessageImpl queryHeader,
                                          final MessagePayload payload) {
        //Your message handling here.
    }
}

The MessageAndClaimsHandler also gets the Jws<Claims> of the DAT Token (which is a JWT Token) of the incoming message.

@SupportedMessageType(NotificationMessageImpl.class)
public class NotificationMessageHandler implements MessageAndClaimsHandler<NotificationMessageImpl> {
    @Override
    public MessageResponse handleMessage(final NotificationMessageImpl queryHeader,
                                         final MessagePayload payload, final Optional<Jws<Claims>> claimsJws) throws MessageHandlerException {
        //Your message and claims handling here.
    }
}