Show server page even without data

web/app/Sensor/LoadAvg.php

@@ -22,8 +22,12 @@ class LoadAvg extends AbstractSensor {
     }
 
     public function getLastValue() {
-        $record = $this->getLastRecord("loadavg")->loadavg;
-        return $this->parse($record);
+        $record = $this->getLastRecord("loadavg");
+        if ($record == null) {
+            return "no data...";
+        }
+        $field = $record->loadavg;
+        return $this->parse($field);
     }
 
     function parse($string) {

web/app/Server.php

@@ -36,11 +36,21 @@ class Server extends Model
      * @return \DateTimeZone
      */
     public function lastRecordTime() {
-        return \Carbon\Carbon::createFromTimestamp($this->lastRecord()->time);
+        $last_record = $this->lastRecord();
+        if ($last_record === null) {
+            return \Carbon\Carbon::createFromTimestamp(0);
+        }
+
+        return \Carbon\Carbon::createFromTimestamp($last_record->time);
     }
 
     public function clientVersion() {
-        return $this->lastRecord()->version;
+        $last_record = $this->lastRecord();
+        if ($last_record == null) {
+            return "none";
+        }
+
+        return $last_record->version;
     }
 
     public function status() {