feat(UtmDataInputStatus): improve isDown logic and timestamp update condition

Author: mjabascal10

backend/src/main/java/com/park/utmstack/domain/UtmDataInputStatus.java

@@ -9,6 +9,7 @@
 import javax.validation.constraints.NotNull;
 import javax.validation.constraints.Size;
 import java.io.Serializable;
+import java.time.Instant;
 import java.util.Objects;
 import java.util.concurrent.TimeUnit;
 
@@ -64,8 +65,8 @@ public class UtmDataInputStatus implements Serializable {
      */
     public Boolean isDown() {
         if (Objects.isNull(timestamp) || Objects.isNull(median))
-            return null;
-        long currentTimeInSeconds = TimeUnit.MILLISECONDS.toSeconds(System.currentTimeMillis());
-        return (currentTimeInSeconds - timestamp) > (median * 6);
+            return false;
+        long now = Instant.now().getEpochSecond();
+        return (now - timestamp) > (median * 1.5);
     }
 }

backend/src/main/java/com/park/utmstack/service/UtmDataInputStatusService.java

@@ -202,7 +202,9 @@ public void syncDataInputStatus() {
 
                     UtmDataInputStatus dataInputStatus = existingOpt
                             .map(existing -> {
-                                existing.setTimestamp(timestamp);
+                                if(timestamp != existing.getTimestamp()) {
+                                    existing.setTimestamp(timestamp);
+                                }
                                 return existing;
                             })
                             .orElseGet(() -> UtmDataInputStatus.builder()