fix: clear mqtt pending commands on request

water-common/water-common-mqtt/src/main/java/org/dromara/mqtt/MqttCommandAckService.java

@@ -132,6 +132,15 @@ public class MqttCommandAckService implements IDeviceCommandAckHandler {
         pendingIds().add(command.getCommandId());
     }
 
+    public int clearPendingCommands() {
+        Set<String> commandIds = pendingIds().readAll();
+        for (String commandId : commandIds) {
+            RedisUtils.deleteObject(pendingKey(commandId));
+        }
+        pendingIds().clear();
+        return commandIds.size();
+    }
+
     public void removePending(String commandId) {
         if (StringUtils.isBlank(commandId)) {
             return;

water-common/water-common-mqtt/src/test/java/org/dromara/mqtt/MqttCommandAckServiceTest.java

@@ -25,6 +25,7 @@ import org.springframework.test.util.ReflectionTestUtils;
 import java.time.Duration;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Supplier;
 
@@ -97,6 +98,48 @@ class MqttCommandAckServiceTest {
         assertThat(MqttCommandAckService.ackMatchesPendingCommand("D01", null)).isFalse();
     }
 
+    @Test
+    void clearPendingCommandsDeletesPendingObjectsAndClearsIds() {
+        MqttProperties properties = new MqttProperties();
+        AppDeviceMapper appDeviceMapper = mock(AppDeviceMapper.class);
+        RedissonClient redissonClient = mock(RedissonClient.class);
+        RSet<String> pendingIds = mock(RSet.class);
+        when(redissonClient.<String>getSet("mqtt:command:pending:ids")).thenReturn(pendingIds);
+        when(pendingIds.readAll()).thenReturn(Set.of("cmd-1", "cmd-2"));
+
+        MqttCommandAckService service = new MqttCommandAckService(properties, appDeviceMapper);
+        try (MockedStatic<RedisUtils> redis = mockStatic(RedisUtils.class)) {
+            redis.when(RedisUtils::getClient).thenReturn(redissonClient);
+
+            int cleared = service.clearPendingCommands();
+
+            assertThat(cleared).isEqualTo(2);
+            redis.verify(() -> RedisUtils.deleteObject("mqtt:command:pending:cmd-1"));
+            redis.verify(() -> RedisUtils.deleteObject("mqtt:command:pending:cmd-2"));
+            verify(pendingIds).clear();
+        }
+    }
+
+    @Test
+    void clearPendingCommandsReturnsZeroForEmptySet() {
+        MqttProperties properties = new MqttProperties();
+        AppDeviceMapper appDeviceMapper = mock(AppDeviceMapper.class);
+        RedissonClient redissonClient = mock(RedissonClient.class);
+        RSet<String> pendingIds = mock(RSet.class);
+        when(redissonClient.<String>getSet("mqtt:command:pending:ids")).thenReturn(pendingIds);
+        when(pendingIds.readAll()).thenReturn(Set.of());
+
+        MqttCommandAckService service = new MqttCommandAckService(properties, appDeviceMapper);
+        try (MockedStatic<RedisUtils> redis = mockStatic(RedisUtils.class)) {
+            redis.when(RedisUtils::getClient).thenReturn(redissonClient);
+
+            int cleared = service.clearPendingCommands();
+
+            assertThat(cleared).isZero();
+            verify(pendingIds).clear();
+        }
+    }
+
     @Test
     void handleAckWaitsBrieflyForCommandLock() throws Exception {
         MqttProperties properties = new MqttProperties();