feat(设备管理): 新增在reactorQL中获取设备属性上报时间 (#592)

Co-authored-by: fighter-wang <11291691+fighter-wang@user.noreply.gitee.com>

jetlinks-manager/device-manager/src/main/java/org/jetlinks/community/device/function/DevicePropertyTimeFunction.java

@@ -0,0 +1,41 @@
+package org.jetlinks.community.device.function;
+
+import org.jetlinks.core.message.DeviceDataManager;
+import org.jetlinks.reactor.ql.supports.map.FunctionMapFeature;
+import org.jetlinks.reactor.ql.utils.CastUtils;
+import org.springframework.stereotype.Component;
+import reactor.core.publisher.Mono;
+
+/**
+ * 在reactorQL中获取设备属性上报时间
+ * <pre>{@code
+ * select device.property_time.recent(deviceId,'temperature',timestamp) recent from ...
+ *
+ * select * from ... where device.property_time.recent(deviceId,'temperature',timestamp)  = 'xxx'
+ * }</pre>
+ *
+ * @author zhouhao
+ * @since 2.2
+ */
+@Component
+public class DevicePropertyTimeFunction extends FunctionMapFeature {
+    public DevicePropertyTimeFunction(DeviceDataManager dataManager) {
+        super("device.property_time.recent", 3, 2, flux -> flux
+            .collectList()
+            .flatMap(args -> {
+                if (args.size() < 2) {
+                    return Mono.empty();
+                }
+                String deviceId = String.valueOf(args.get(0));
+                String property = String.valueOf(args.get(1));
+                long timestamp = args.size() > 2
+                    ? CastUtils.castNumber(args.get(2))
+                               .longValue()
+                    : System.currentTimeMillis();
+
+                return dataManager
+                    .getLastProperty(deviceId, property, timestamp)
+                    .map(DeviceDataManager.PropertyValue::getTimestamp);
+            }));
+    }
+}