Fix null ref exception caused by missing system properties in the message

build.sbt

@@ -6,7 +6,7 @@ organization := "com.microsoft.azure.iot"
 //version := "0.10.0"
 
 //https://bintray.com/microsoftazuretoketi/toketi-repo/iothub-react
-version := "0.10.0-DEV.170725b"
+version := "0.10.0-DEV.170725c"
 
 scalaVersion := "2.12.2"
 crossScalaVersions := Seq("2.11.11", "2.12.2")

samples-java/pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>com.microsoft.azure.iot</groupId>
     <artifactId>iothub-react-demo</artifactId>
-    <version>0.10.0-DEV.170725b</version>
+    <version>0.10.0-DEV.170725c</version>
 
     <repositories>
         <repository>
@@ -20,7 +20,7 @@
         <dependency>
             <groupId>com.microsoft.azure.iot</groupId>
             <artifactId>iothub-react_2.12</artifactId>
-            <version>0.10.0-DEV.170725b</version>
+            <version>0.10.0-DEV.170725c</version>
         </dependency>
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>

src/main/scala/com/microsoft/azure/iot/iothubreact/MessageFromDevice.scala

@@ -89,10 +89,16 @@ class MessageFromDevice(
   lazy val sequenceNumber: Long = systemProps.getSequenceNumber
 
   // ID of the device who sent the message
-  lazy val deviceId: String = systemProps.get(deviceIdProperty).toString
+  lazy val deviceId: String = {
+    val p = systemProps.get(deviceIdProperty)
+    if (p != null) p.toString else ""
+  }
 
   // Message ID
-  lazy val messageId: String = systemProps.get(messageIdProperty).toString
+  lazy val messageId: String = {
+    val p = systemProps.get(messageIdProperty)
+    if (p != null) p.toString else ""
+  }
 
   // IoT message content bytes
   lazy val content: Array[Byte] = data.get.getBytes