Add support for websocket subscriptions

src/test/java/ca/uhn/fhir/jpa/starter/SocketImplementation.java

@@ -0,0 +1,88 @@
+
+package ca.uhn.fhir.jpa.starter;
+
+import ca.uhn.fhir.rest.api.EncodingEnum;
+import org.eclipse.jetty.websocket.api.Session;
+import org.eclipse.jetty.websocket.api.annotations.OnWebSocketConnect;
+import org.eclipse.jetty.websocket.api.annotations.OnWebSocketMessage;
+import org.eclipse.jetty.websocket.api.annotations.WebSocket;
+import org.slf4j.Logger;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@WebSocket
+public class SocketImplementation {
+
+	private static final Logger ourLog = org.slf4j.LoggerFactory.getLogger(SocketImplementation.class);
+	private String myCriteria;
+	protected String myError;
+	protected boolean myGotBound;
+	private List<String> myMessages = new ArrayList<String>();
+	protected int myPingCount;
+	protected String mySubsId;
+	private Session session;
+
+	public SocketImplementation(String theCriteria, EncodingEnum theEncoding) {
+		myCriteria = theCriteria;
+	}
+
+	public List<String> getMessages() {
+		return myMessages;
+	}
+
+	public void keepAlive() {
+		if (this.session != null) {
+			try {
+				session.getRemote().sendString("keep alive");
+			} catch (Throwable t) {
+				ourLog.error("Failure", t);
+			}
+		}
+	}
+
+	/**
+	 * This method is executed when the client is connecting to the server.
+	 * In this case, we are sending a message to create the subscription dynamiclly
+	 *
+	 * @param session
+	 */
+	@OnWebSocketConnect
+	public void onConnect(Session session) {
+		ourLog.info("Got connect: {}", session);
+		this.session = session;
+		try {
+			String sending = "bind " + myCriteria;
+			ourLog.info("Sending: {}", sending);
+			session.getRemote().sendString(sending);
+
+			ourLog.info("Connection: DONE");
+		} catch (Throwable t) {
+			t.printStackTrace();
+			ourLog.error("Failure", t);
+		}
+	}
+
+	/**
+	 * This is the message handler for the client
+	 *
+	 * @param theMsg
+	 */
+	@OnWebSocketMessage
+	public void onMessage(String theMsg) {
+		ourLog.info("Got msg: " + theMsg);
+		myMessages.add(theMsg);
+
+		if (theMsg.startsWith("bound ")) {
+			myGotBound = true;
+			mySubsId = (theMsg.substring("bound ".length()));
+		} else if (myGotBound && theMsg.startsWith("add " + mySubsId + "\n")) {
+			String text = theMsg.substring(("add " + mySubsId + "\n").length());
+			ourLog.info("text: " + text);
+		} else if (theMsg.startsWith("ping ")) {
+			myPingCount++;
+		} else {
+			myError = "Unexpected message: " + theMsg;
+		}
+	}
+}