Implement cluster broadcasting

7 files changed, 238 insertions, 6 deletions

diff --git a/src/main/java/org/traccar/Context.java b/src/main/java/org/traccar/Context.java
index aeba9c4c9..c44d432b2 100644
--- a/src/main/java/org/traccar/Context.java
+++ b/src/main/java/org/traccar/Context.java
@@ -20,6 +20,7 @@ import com.fasterxml.jackson.databind.SerializationFeature;
 import com.fasterxml.jackson.datatype.jsr353.JSR353Module;
 import org.apache.velocity.app.VelocityEngine;
 import org.eclipse.jetty.util.URIUtil;
+import org.traccar.broadcast.BroadcastService;
 import org.traccar.config.Config;
 import org.traccar.config.Keys;
 import org.traccar.database.AttributesManager;
@@ -171,6 +172,12 @@ public final class Context {
         return scheduleManager;
     }
 
+    private static BroadcastService broadcastService;
+
+    public static BroadcastService getBroadcastService() {
+        return broadcastService;
+    }
+
     private static GeofenceManager geofenceManager;
 
     public static GeofenceManager getGeofenceManager() {
@@ -335,6 +342,10 @@ public final class Context {
         serverManager = new ServerManager();
         scheduleManager = new ScheduleManager();
 
+        if (config.hasKey(Keys.BROADCAST_ADDRESS)) {
+            broadcastService = new BroadcastService(config, objectMapper);
+        }
+
         if (config.hasKey(Keys.EVENT_FORWARD_URL)) {
             eventForwarder = new EventForwarder();
         }
diff --git a/src/main/java/org/traccar/Main.java b/src/main/java/org/traccar/Main.java
index 6daf72bb4..2eaf394af 100644
--- a/src/main/java/org/traccar/Main.java
+++ b/src/main/java/org/traccar/Main.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012 - 2020 Anton Tananaev (anton@traccar.org)
+ * Copyright 2012 - 2022 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -118,13 +118,14 @@ public final class Main {
 
             List<LifecycleObject> services = new LinkedList<>();
             services.add(Context.getServerManager());
-            if (Context.getWebServer() != null) {
-                services.add(Context.getWebServer());
-            }
+            services.add(Context.getWebServer());
             services.add(Context.getScheduleManager());
+            services.add(Context.getBroadcastService());
 
             for (LifecycleObject service : services) {
-                service.start();
+                if (service != null) {
+                    service.start();
+                }
             }
 
             Thread.setDefaultUncaughtExceptionHandler((t, e) -> LOGGER.error("Thread exception", e));
@@ -134,7 +135,9 @@ public final class Main {
 
                 Collections.reverse(services);
                 for (LifecycleObject service : services) {
-                    service.stop();
+                    if (service != null) {
+                        service.stop();
+                    }
                 }
             }));
         } catch (Exception e) {
diff --git a/src/main/java/org/traccar/MainEventHandler.java b/src/main/java/org/traccar/MainEventHandler.java
index a3f6f4105..0e60ac06d 100644
--- a/src/main/java/org/traccar/MainEventHandler.java
+++ b/src/main/java/org/traccar/MainEventHandler.java
@@ -23,12 +23,14 @@ import io.netty.handler.codec.http.HttpRequestDecoder;
 import io.netty.handler.timeout.IdleStateEvent;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.traccar.broadcast.BroadcastMessage;
 import org.traccar.config.Keys;
 import org.traccar.database.StatisticsManager;
 import org.traccar.helper.DateUtil;
 import org.traccar.model.Position;
 import org.traccar.storage.StorageException;
 
+import java.io.IOException;
 import java.util.Arrays;
 import java.util.HashSet;
 import java.util.LinkedHashSet;
@@ -61,6 +63,14 @@ public class MainEventHandler extends ChannelInboundHandlerAdapter {
                 LOGGER.warn("Failed to update device", error);
             }
 
+            BroadcastMessage message = new BroadcastMessage();
+            message.setPosition(position);
+            try {
+                Context.getBroadcastService().sendMessage(message);
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+
             String uniqueId = Context.getIdentityManager().getById(position.getDeviceId()).getUniqueId();
 
             StringBuilder builder = new StringBuilder();
diff --git a/src/main/java/org/traccar/broadcast/BroadcastMessage.java b/src/main/java/org/traccar/broadcast/BroadcastMessage.java
new file mode 100644
index 000000000..6b103f373
--- /dev/null
+++ b/src/main/java/org/traccar/broadcast/BroadcastMessage.java
@@ -0,0 +1,42 @@
+/*
+ * Copyright 2022 Anton Tananaev (anton@traccar.org)
+ *
+ * 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.traccar.broadcast;
+
+import org.traccar.model.Position;
+
+public class BroadcastMessage {
+
+    private DeviceStatus deviceStatus;
+
+    public DeviceStatus getDeviceStatus() {
+        return deviceStatus;
+    }
+
+    public void setDeviceStatus(DeviceStatus deviceStatus) {
+        this.deviceStatus = deviceStatus;
+    }
+
+    private Position position;
+
+    public Position getPosition() {
+        return position;
+    }
+
+    public void setPosition(Position position) {
+        this.position = position;
+    }
+
+}
diff --git a/src/main/java/org/traccar/broadcast/BroadcastService.java b/src/main/java/org/traccar/broadcast/BroadcastService.java
new file mode 100644
index 000000000..b17857fcd
--- /dev/null
+++ b/src/main/java/org/traccar/broadcast/BroadcastService.java
@@ -0,0 +1,100 @@
+/*
+ * Copyright 2022 Anton Tananaev (anton@traccar.org)
+ *
+ * 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.traccar.broadcast;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.traccar.LifecycleObject;
+import org.traccar.config.Config;
+import org.traccar.config.Keys;
+
+import javax.inject.Inject;
+import java.io.IOException;
+import java.net.DatagramPacket;
+import java.net.DatagramSocket;
+import java.net.InetAddress;
+import java.net.MulticastSocket;
+import java.nio.charset.StandardCharsets;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+public class BroadcastService implements LifecycleObject {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(BroadcastService.class);
+
+    private final ObjectMapper objectMapper;
+
+    private final InetAddress address;
+    private final int port;
+
+    private DatagramSocket publisherSocket;
+
+    private final ExecutorService service = Executors.newSingleThreadExecutor();
+    private final byte[] receiverBuffer = new byte[4096];
+
+    @Inject
+    public BroadcastService(Config config, ObjectMapper objectMapper) throws IOException {
+        this.objectMapper = objectMapper;
+        address = InetAddress.getByName(config.getString(Keys.BROADCAST_ADDRESS));
+        port = config.getInteger(Keys.BROADCAST_PORT);
+    }
+
+    public void sendMessage(BroadcastMessage message) throws IOException {
+        byte[] buffer = objectMapper.writeValueAsString(message).getBytes(StandardCharsets.UTF_8);
+        DatagramPacket packet = new DatagramPacket(buffer, buffer.length, address, port);
+        publisherSocket.send(packet);
+    }
+
+    private void handleMessage(BroadcastMessage message) {
+        if (message.getDeviceStatus() != null) {
+            LOGGER.info("Broadcast received device {}", message.getDeviceStatus().getDeviceId());
+        } else if (message.getPosition() != null) {
+            LOGGER.info("Broadcast received position {}", message.getPosition().getDeviceId());
+        }
+    }
+
+    @Override
+    public void start() throws IOException {
+        service.submit(receiver);
+        publisherSocket = new DatagramSocket();
+    }
+
+    @Override
+    public void stop() {
+        publisherSocket.close();
+        service.shutdown();
+    }
+
+    private final Runnable receiver = new Runnable() {
+        @Override
+        public void run() {
+            try (MulticastSocket socket = new MulticastSocket(port)) {
+                socket.joinGroup(address);
+                while (!service.isShutdown()) {
+                    DatagramPacket packet = new DatagramPacket(receiverBuffer, receiverBuffer.length);
+                    socket.receive(packet);
+                    String data = new String(packet.getData(), 0, packet.getLength(), StandardCharsets.UTF_8);
+                    handleMessage(objectMapper.readValue(data, BroadcastMessage.class));
+                }
+                socket.leaveGroup(address);
+            } catch (IOException e) {
+                throw new RuntimeException(e);
+            }
+        }
+    };
+
+}
diff --git a/src/main/java/org/traccar/broadcast/DeviceStatus.java b/src/main/java/org/traccar/broadcast/DeviceStatus.java
new file mode 100644
index 000000000..4f0143319
--- /dev/null
+++ b/src/main/java/org/traccar/broadcast/DeviceStatus.java
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2022 Anton Tananaev (anton@traccar.org)
+ *
+ * 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.traccar.broadcast;
+
+import java.util.Date;
+
+public class DeviceStatus {
+
+    private long deviceId;
+
+    public long getDeviceId() {
+        return deviceId;
+    }
+
+    public void setDeviceId(long deviceId) {
+        this.deviceId = deviceId;
+    }
+
+    private String status;
+
+    public String getStatus() {
+        return status;
+    }
+
+    public void setStatus(String status) {
+        this.status = status;
+    }
+
+    private Date lastUpdate;
+
+    public Date getLastUpdate() {
+        return this.lastUpdate;
+    }
+
+    public void setLastUpdate(Date lastUpdate) {
+        this.lastUpdate = lastUpdate;
+    }
+
+}
diff --git a/src/main/java/org/traccar/config/Keys.java b/src/main/java/org/traccar/config/Keys.java
index ccfe4bee7..dc6bcbec9 100644
--- a/src/main/java/org/traccar/config/Keys.java
+++ b/src/main/java/org/traccar/config/Keys.java
@@ -1309,4 +1309,18 @@ public final class Keys {
             Collections.singletonList(KeyType.GLOBAL),
             "time,position,speed,course,accuracy,result");
 
+    /**
+     * Multicast address for broadcasting synchronization events.
+     */
+    public static final ConfigKey<String> BROADCAST_ADDRESS = new ConfigKey<>(
+            "broadcast.address",
+            Collections.singletonList(KeyType.GLOBAL));
+
+    /**
+     * Multicast port for broadcasting synchronization events.
+     */
+    public static final ConfigKey<Integer> BROADCAST_PORT = new ConfigKey<>(
+            "broadcast.port",
+            Collections.singletonList(KeyType.GLOBAL));
+
 }