1 files changed, 137 insertions, 0 deletions
diff --git a/framework/src/onos/utils/stc/src/main/java/org/onlab/stc/MonitorWebSocketServlet.java b/framework/src/onos/utils/stc/src/main/java/org/onlab/stc/MonitorWebSocketServlet.java
new file mode 100644
index 00000000..a8705003
--- /dev/null
+++ b/framework/src/onos/utils/stc/src/main/java/org/onlab/stc/MonitorWebSocketServlet.java
@@ -0,0 +1,137 @@
+/*
+ * 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.onlab.stc;
+
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.google.common.io.ByteStreams;
+import com.google.common.net.MediaType;
+import org.eclipse.jetty.websocket.WebSocket;
+import org.eclipse.jetty.websocket.WebSocketServlet;
+
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Set;
+import java.util.Timer;
+import java.util.TimerTask;
+
+/**
+ * Web socket servlet capable of creating web sockets for the STC monitor.
+ */
+public class MonitorWebSocketServlet extends WebSocketServlet
+        implements MonitorDelegate {
+
+    private static final long PING_DELAY_MS = 5000;
+    private static final String DOT = ".";
+
+    private static Monitor monitor;
+    private static MonitorWebSocketServlet instance;
+
+    private final Set<MonitorWebSocket> sockets = new HashSet<>();
+    private final Timer timer = new Timer();
+    private final TimerTask pruner = new Pruner();
+
+    /**
+     * Binds the shared process flow monitor.
+     *
+     * @param m process monitor reference
+     */
+    public static void setMonitor(Monitor m) {
+        monitor = m;
+    }
+
+    /**
+     * Closes all currently open monitor web-sockets.
+     */
+    public static void closeAll() {
+        if (instance != null) {
+            instance.sockets.forEach(MonitorWebSocket::close);
+            instance.sockets.clear();
+        }
+    }
+
+    @Override
+    public void init() throws ServletException {
+        super.init();
+        instance = this;
+        monitor.setDelegate(this);
+        timer.schedule(pruner, PING_DELAY_MS, PING_DELAY_MS);
+    }
+
+    @Override
+    protected void doGet(HttpServletRequest req, HttpServletResponse resp)
+            throws ServletException, IOException {
+        String uri = req.getRequestURI();
+        uri = uri.length() <= 1 ? "/index.html" : uri;
+        InputStream resource = getClass().getResourceAsStream(uri);
+        if (resource == null) {
+            resp.setStatus(HttpServletResponse.SC_NOT_FOUND);
+        } else {
+            byte[] entity = ByteStreams.toByteArray(resource);
+            resp.setStatus(HttpServletResponse.SC_OK);
+            resp.setContentType(contentType(uri).toString());
+            resp.setContentLength(entity.length);
+            resp.getOutputStream().write(entity);
+        }
+    }
+
+    private MediaType contentType(String uri) {
+        int sep = uri.lastIndexOf(DOT);
+        String ext = sep > 0 ? uri.substring(sep + 1) : null;
+        return ext == null ? MediaType.APPLICATION_BINARY :
+                ext.equals("html") ? MediaType.HTML_UTF_8 :
+                        ext.equals("js") ? MediaType.JAVASCRIPT_UTF_8 :
+                                ext.equals("css") ? MediaType.CSS_UTF_8 :
+                                        MediaType.APPLICATION_BINARY;
+    }
+
+    @Override
+    public WebSocket doWebSocketConnect(HttpServletRequest request, String protocol) {
+        MonitorWebSocket socket = new MonitorWebSocket(monitor);
+        synchronized (sockets) {
+            sockets.add(socket);
+        }
+        return socket;
+    }
+
+    @Override
+    public void notify(ObjectNode event) {
+        if (instance != null) {
+            instance.sockets.forEach(ws -> ws.sendMessage(event));
+        }
+    }
+
+    // Task for pruning web-sockets that are idle.
+    private class Pruner extends TimerTask {
+        @Override
+        public void run() {
+            synchronized (sockets) {
+                Iterator<MonitorWebSocket> it = sockets.iterator();
+                while (it.hasNext()) {
+                    MonitorWebSocket socket = it.next();
+                    if (socket.isIdle()) {
+                        it.remove();
+                        socket.close();
+                    }
+                }
+            }
+        }
+    }
+}