Db.LoadSelect throws NullReferenceException - servicestack

Question

Starting to pull my hair out over this, so thought I might try asking here.
I have this simple service:
public class EventService : Service
{
public object Get(GetEvents request)
{
return Db.LoadSelect<Event>();
}
}
The LoadSelect() throws a NullReferenceException.
I actually had it working perfectly earlier, but have no idea what is now causing it to throw the exception.
Have tracked it down to this line that is actually throwing the exception within ServiceStack (ServiceStack.OrmLite.Support.LoadList):
LoadList-NullReferenceException
But looking at the locals, everything seems fine to me. I mean, it can obviously get the data from the database, so that part is fine, the data is correct, and it even seems to resolve the ForeignKeys, and everything.
So what value it can't get, or isn't set, I have no idea :/
Any tips on how to troubleshoot this further would be great! =)
[EDIT1 - Here are the POCOs]
public class Event
{
[PrimaryKey]
public int Id { get; set; }
public int Timestamp { get; set; }
public int MessageId { get; set; }
[Reference]
public Message Message { get; }
}
public class Message
{
[PrimaryKey]
public int Id { get; set; }
public string Text { get; set; }
}
[EDIT2 - Findings after reading through the dup answer]
As mentioned in the initial question, the basic NullReferenceException troubleshooting has been performed, and I have dug as deep as I can into the ServiceStack framework to try and identify the culprit.
As far as I can see, all variables that are consumed by the call throwing the exception are okey (see screenshot below).
The only one (highlighted in the image below), should be handled by the ServiceStack OrmLite References API, but maybe someone more familier with the framework can comment, but it all looks good to me atleast...
LoadList-NullReferenceException-002
Perhaps I'm using the References API wrong?
The database structure is quite simple:
Event Table
| Event | CREATE TABLE `Event` (
`Id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`Timestamp` int(11) NOT NULL,
`MessageId` int(4) unsigned NOT NULL,
PRIMARY KEY (`Id`),
KEY `MessageId_FK` (`MessageId`),
CONSTRAINT `MessageId_FK` FOREIGN KEY (`MessageId`) REFERENCES `Message` (`Id`) ON UPDATE CASCADE
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8 |
mysql> SELECT * FROM Event;
+----+------------+-----------+
| Id | Timestamp | MessageId |
+----+------------+-----------+
| 1 | 1501026747 | 1 |
| 2 | 1501027047 | 1 |
+----+------------+-----------+
Message Table
| Message | CREATE TABLE `Message` (
`Id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`Text` varchar(255) NOT NULL,
PRIMARY KEY (`Id`),
UNIQUE KEY `Id_UNIQUE` (`Id`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8 |
mysql> SELECT * FROM Message;
+----+---------------------------------------------+
| Id | Text |
+----+---------------------------------------------+
| 1 | Someone is at the door! |
| 2 | 1 has acknowledged the notification. |
| 3 | 2 has acknowledged the notification. |
| 4 | 3 has acknowledged the notification. |
+----+---------------------------------------------+
Exception details
System.NullReferenceException occurred
HResult=0x80004003
Message=Object reference not set to an instance of an object.
Source=ServiceStack.OrmLite
StackTrace:
at ServiceStack.OrmLite.Support.LoadList`2.SetRefSelfChildResults(FieldDefinition fieldDef, ModelDefinition refModelDef, FieldDefinition refSelf, IList childResults) in C:\TeamCity\buildAgent\work\12884bd5feef0ce7\src\ServiceStack.OrmLite\Support\LoadList.cs:line 154

Answer 1

To answer my own question, for some reason, I decided to remove the setter on the reference property of one of the POCOs (Event.Message).
[Reference]
public Message Message { get; }
Should of course have been (and was at some point, which is why it worked for a short time):
[Reference]
public Message Message { get; set; }
No wonder ServiceStack couldn't set the property, and then use it for the References API.