From 5877cb1b3f1fa7331c4310b9754a3ec442586497 Mon Sep 17 00:00:00 2001
From: Anton Tananaev <anton@traccar.org>
Date: Sun, 13 Nov 2022 11:48:43 -0800
Subject: Refactor position forwarding

---
 .../org/traccar/PositionForwardingHandler.java     | 141 +++++++++++++++++++++
 1 file changed, 141 insertions(+)
 create mode 100644 src/main/java/org/traccar/PositionForwardingHandler.java

(limited to 'src/main/java/org/traccar/PositionForwardingHandler.java')

diff --git a/src/main/java/org/traccar/PositionForwardingHandler.java b/src/main/java/org/traccar/PositionForwardingHandler.java
new file mode 100644
index 000000000..83f91e937
--- /dev/null
+++ b/src/main/java/org/traccar/PositionForwardingHandler.java
@@ -0,0 +1,141 @@
+/*
+ * Copyright 2015 - 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;
+
+import io.netty.channel.ChannelHandler;
+import io.netty.util.Timeout;
+import io.netty.util.Timer;
+import io.netty.util.TimerTask;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.traccar.config.Config;
+import org.traccar.config.Keys;
+import org.traccar.forward.PositionData;
+import org.traccar.forward.PositionForwarder;
+import org.traccar.forward.ResultHandler;
+import org.traccar.model.Device;
+import org.traccar.model.Position;
+import org.traccar.session.cache.CacheManager;
+
+import javax.annotation.Nullable;
+import javax.inject.Inject;
+import javax.inject.Singleton;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+
+@Singleton
+@ChannelHandler.Sharable
+public class PositionForwardingHandler extends BaseDataHandler {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(PositionForwardingHandler.class);
+
+    private final CacheManager cacheManager;
+    private final Timer timer;
+
+    private final PositionForwarder positionForwarder;
+
+    private final boolean retryEnabled;
+    private final int retryDelay;
+    private final int retryCount;
+    private final int retryLimit;
+
+    private final AtomicInteger deliveryPending;
+
+    @Inject
+    public PositionForwardingHandler(
+            Config config, CacheManager cacheManager, Timer timer, @Nullable PositionForwarder positionForwarder) {
+
+        this.cacheManager = cacheManager;
+        this.timer = timer;
+        this.positionForwarder = positionForwarder;
+
+        this.retryEnabled = config.getBoolean(Keys.FORWARD_RETRY_ENABLE);
+        this.retryDelay = config.getInteger(Keys.FORWARD_RETRY_DELAY);
+        this.retryCount = config.getInteger(Keys.FORWARD_RETRY_COUNT);
+        this.retryLimit = config.getInteger(Keys.FORWARD_RETRY_LIMIT);
+
+        this.deliveryPending = new AtomicInteger();
+    }
+
+    class AsyncRequestAndCallback implements ResultHandler, TimerTask {
+
+        private final PositionData positionData;
+
+        private int retries = 0;
+
+        AsyncRequestAndCallback(PositionData positionData) {
+            this.positionData = positionData;
+            deliveryPending.incrementAndGet();
+        }
+
+        private void send() {
+            positionForwarder.forward(positionData, this);
+        }
+
+        private void retry(Throwable throwable) {
+            boolean scheduled = false;
+            try {
+                if (retryEnabled && deliveryPending.get() <= retryLimit && retries < retryCount) {
+                    schedule();
+                    scheduled = true;
+                }
+            } finally {
+                int pending = scheduled ? deliveryPending.get() : deliveryPending.decrementAndGet();
+                LOGGER.warn("Position forwarding failed: " + pending + " pending", throwable);
+            }
+        }
+
+        private void schedule() {
+            timer.newTimeout(this, retryDelay * (long) Math.pow(2, retries++), TimeUnit.MILLISECONDS);
+        }
+
+        @Override
+        public void onResult(boolean success, Throwable throwable) {
+            if (success) {
+                deliveryPending.decrementAndGet();
+            } else {
+                retry(throwable);
+            }
+        }
+
+        @Override
+        public void run(Timeout timeout) {
+            boolean sent = false;
+            try {
+                if (!timeout.isCancelled()) {
+                    send();
+                    sent = true;
+                }
+            } finally {
+                if (!sent) {
+                    deliveryPending.decrementAndGet();
+                }
+            }
+        }
+    }
+
+    @Override
+    protected Position handlePosition(Position position) {
+        if (positionForwarder != null) {
+            PositionData positionData = new PositionData();
+            positionData.setPosition(position);
+            positionData.setDevice(cacheManager.getObject(Device.class, position.getDeviceId()));
+            new AsyncRequestAndCallback(positionData).send();
+        }
+        return position;
+    }
+
+}
-- 
cgit v1.2.3