Best way to handle incoming messages with XMPP - xmpp

Question

Is there a work-around to get Spring to handle incoming messages from XMPP? I have tried many different configurations to get an inbound-channel-adapter to respond to incoming XMPP messages and nothing happens. I know that they show up at the Spring Integration layer (I can see that in the logs) but they are ignored. Is there any way to get them into my application layer? I hope to avoid needing to make changes to Spring Integration itself if I can.
Here is my integration configuration:
<int-xmpp:inbound-channel-adapter id="gcmIn"
channel="gcmInChannel"
xmpp-connection="gcmConnection"
auto-startup="true"
/>
<bean id="inboundBean" class="example.integration.GcmInputHandler"/>
<int:service-activator input-channel="gcmInChannel" output-channel="nullChannel" ref="inboundBean" method="handle"/>
Using the outbound-channel-adapter works fine. I can send messages over GCM 100% easily. But inbound does nothing, even though I know the messages are coming in.
Thanks

Answer 1

Not a very clean one, you would need to overwrite the ChatMessageListeningEndpoint, which drops all empty body messages.
This one needs then to be used as inbound-channel adapter in your config.
In addition you need to register the GCM package extension on the Smack Provider Manager, otherwise you lose the JSON message.
Working on a sample project -- so if you need more help let me know and I will post a link as soon it works somehow in a understandable way.
Here a sample GCM Input Adapter
public class GcmMessageListeningEndpoint extends ChatMessageListeningEndpoint {
private static final Logger LOG = LoggerFactory.getLogger(GcmMessageListeningEndpoint.class);
#Setter
protected PacketListener packetListener = new GcmPacketListener();
protected XmppHeaderMapper headerMapper = new DefaultXmppHeaderMapper();
public GcmMessageListeningEndpoint(XMPPConnection connection) {
super(connection);
ProviderManager.addExtensionProvider(GcmPacketExtension.GCM_ELEMENT_NAME, GcmPacketExtension.GCM_NAMESPACE,
new PacketExtensionProvider() {
#Override
public PacketExtension parseExtension(XmlPullParser parser) throws Exception {
String json = parser.nextText();
return new GcmPacketExtension(json);
}
});
}
#Override
public void setHeaderMapper(XmppHeaderMapper headerMapper) {
super.setHeaderMapper(headerMapper);
this.headerMapper = headerMapper;
if (this.headerMapper == null) throw new IllegalArgumentException("Null XmppHeaderMapper isn't supported!");
}
public String getComponentType() {
return "xmpp:inbound-channel-adapter-gcm";
}
#Override
protected void doStart() {
Assert.isTrue(this.initialized, this.getComponentName() + " [" + this.getComponentType() + "] must be initialized");
this.xmppConnection.addPacketListener(this.packetListener, null);
}
#Override
protected void doStop() {
if (this.xmppConnection != null) {
this.xmppConnection.removePacketListener(this.packetListener);
}
}
class GcmPacketListener implements PacketListener {
#Override
public void processPacket(Packet packet) throws NotConnectedException {
if (packet instanceof org.jivesoftware.smack.packet.Message) {
org.jivesoftware.smack.packet.Message xmppMessage = (org.jivesoftware.smack.packet.Message) packet;
Map<String, ?> mappedHeaders = headerMapper.toHeadersFromRequest(xmppMessage);
sendMessage(MessageBuilder.withPayload(xmppMessage).copyHeaders(mappedHeaders).build());
} else {
LOG.warn("Unsuported Packet {}", packet);
}
}
}
}
And here the new configuration for the inbound-channel-adapter remove the one in XML:
#Bean
public GcmMessageListeningEndpoint inboundAdpater(XMPPConnection connection, MessageChannel gcmInChannel) {
GcmMessageListeningEndpoint endpoint = new GcmMessageListeningEndpoint(connection);
endpoint.setOutputChannel(gcmInChannel);
return endpoint;
}