ONOS-1235 Enhanced UI extension mechanism to provide message handler factory and took a first cut at the core UiWebSocket mechanism.
Change-Id: Iaad080c5371c3aa5e24a23489b1679d373ec0720
diff --git a/web/gui/src/main/java/org/onosproject/ui/impl/UiWebSocket.java b/web/gui/src/main/java/org/onosproject/ui/impl/UiWebSocket.java
new file mode 100644
index 0000000..9b11b42
--- /dev/null
+++ b/web/gui/src/main/java/org/onosproject/ui/impl/UiWebSocket.java
@@ -0,0 +1,161 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.ui.impl;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.eclipse.jetty.websocket.WebSocket;
+import org.onlab.osgi.ServiceDirectory;
+import org.onosproject.ui.UiConnection;
+import org.onosproject.ui.UiExtensionService;
+import org.onosproject.ui.UiMessageHandler;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Web socket capable of interacting with the GUI.
+ */
+public class UiWebSocket
+ implements UiConnection, WebSocket.OnTextMessage, WebSocket.OnControl {
+
+ private static final Logger log = LoggerFactory.getLogger(UiWebSocket.class);
+
+ private static final long MAX_AGE_MS = 15000;
+
+ private static final byte PING = 0x9;
+ private static final byte PONG = 0xA;
+ private static final byte[] PING_DATA = new byte[]{(byte) 0xde, (byte) 0xad};
+
+ private final ServiceDirectory directory;
+
+ private Connection connection;
+ private FrameConnection control;
+
+ private final ObjectMapper mapper = new ObjectMapper();
+
+ private long lastActive = System.currentTimeMillis();
+
+ private Map<String, UiMessageHandler> handlers;
+
+ /**
+ * Creates a new web-socket for serving data to GUI.
+ *
+ * @param directory service directory
+ */
+ public UiWebSocket(ServiceDirectory directory) {
+ this.directory = directory;
+ }
+
+ /**
+ * Issues a close on the connection.
+ */
+ synchronized void close() {
+ destroyHandlers();
+ if (connection.isOpen()) {
+ connection.close();
+ }
+ }
+
+ /**
+ * Indicates if this connection is idle.
+ *
+ * @return true if idle or closed
+ */
+ synchronized boolean isIdle() {
+ boolean idle = (System.currentTimeMillis() - lastActive) > MAX_AGE_MS;
+ if (idle || (connection != null && !connection.isOpen())) {
+ return true;
+ } else if (connection != null) {
+ try {
+ control.sendControl(PING, PING_DATA, 0, PING_DATA.length);
+ } catch (IOException e) {
+ log.warn("Unable to send ping message due to: ", e);
+ }
+ }
+ return false;
+ }
+
+ @Override
+ public void onOpen(Connection connection) {
+ log.info("GUI client connected");
+ this.connection = connection;
+ this.control = (FrameConnection) connection;
+ createHandlers();
+ }
+
+ @Override
+ public synchronized void onClose(int closeCode, String message) {
+ destroyHandlers();
+ log.info("GUI client disconnected");
+ }
+
+ @Override
+ public boolean onControl(byte controlCode, byte[] data, int offset, int length) {
+ lastActive = System.currentTimeMillis();
+ return true;
+ }
+
+ @Override
+ public void onMessage(String data) {
+ lastActive = System.currentTimeMillis();
+ try {
+ ObjectNode message = (ObjectNode) mapper.reader().readTree(data);
+ String type = message.path("type").asText("unknown");
+ UiMessageHandler handler = handlers.get(type);
+ if (handler != null) {
+ handler.process(message);
+ } else {
+ log.warn("No GUI message handler for type {}", type);
+ }
+ } catch (Exception e) {
+ log.warn("Unable to parse GUI message {} due to {}", data, e);
+ log.debug("Boom!!!", e);
+ }
+ }
+
+ @Override
+ public void sendMessage(ObjectNode message) {
+ try {
+ if (connection.isOpen()) {
+ connection.sendMessage(message.toString());
+ }
+ } catch (IOException e) {
+ log.warn("Unable to send message {} to GUI due to {}", message, e);
+ log.debug("Boom!!!", e);
+ }
+ }
+
+ // Creates new message handlers.
+ private void createHandlers() {
+ handlers = new HashMap<>();
+ UiExtensionService service = directory.get(UiExtensionService.class);
+ service.getExtensions().forEach(ext -> ext.messageHandlerFactory().newHandlers().forEach(handler -> {
+ handler.init(this, directory);
+ handler.messageTypes().forEach(type -> handlers.put(type, handler));
+ }));
+ }
+
+ // Destroys message handlers.
+ private synchronized void destroyHandlers() {
+ handlers.forEach((type, handler) -> handler.destroy());
+ handlers.clear();
+ }
+}
+