I receive an error message when exposing an ADO.NET Data Service using an Entity Framework data model that contains an entity (called "Case") with an internal setter on a property. If I modify the setter to be public (using the entity designer), the data services works fine.
I don’t need the entity "Case" exposed in the data service, so I tried to limit which entities are exposed using SetEntitySetAccessRule. This didn’t work, and service end point fails with the same error.
public static void InitializeService(IDataServiceConfiguration config)
{
config.SetEntitySetAccessRule("User", EntitySetRights.AllRead);
}
The error message is reported in a browser when the .svc endpoint is called. It is very generic, and reads “Request Error. The server encountered an error processing the request. See server logs for more details.” Unfortunately, there are no entries in the System and Application event logs.
I found this stackoverflow question that shows how to configure tracing on the service. After doing so, the following NullReferenceExceptoin error was reported in the trace log.
Does anyone know how to avoid this exception when including an entity with an internal setter?
<E2ETraceEvent xmlns="http://schemas.microsoft.com/2004/06/E2ETraceEvent">
<System xmlns="http://schemas.microsoft.com/2004/06/windows/eventlog/system">
<EventID>131076</EventID>
<Type>3</Type>
<SubType Name="Error">0</SubType>
<Level>2</Level>
<TimeCreated SystemTime="2008-11-05T22:30:44.1523578Z" />
<Source Name="System.ServiceModel" />
<Correlation ActivityID="{da77ee97-960f-4275-a5e7-a181c0b024b1}" />
<Execution ProcessName="WebDev.WebServer" ProcessID="6388" ThreadID="8" />
<Channel />
<Computer>MOTOJIM</Computer>
</System>
<ApplicationData>
<TraceData>
<DataItem>
<TraceRecord xmlns="http://schemas.microsoft.com/2004/10/E2ETraceEvent/TraceRecord" Severity="Error">
<TraceIdentifier>http://msdn.microsoft.com/en-US/library/System.ServiceModel.Diagnostics.TraceHandledException.aspx</TraceIdentifier>
<Description>Handling an exception.</Description>
<AppDomain>685a2910-19-128703978432492675</AppDomain>
<Exception>
<ExceptionType>System.NullReferenceException, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</ExceptionType>
<Message>Object reference not set to an instance of an object.</Message>
<StackTrace>
at System.Data.Services.Providers.ObjectContextServiceProvider.PopulateMemberMetadata(ResourceType resourceType, MetadataWorkspace workspace, IDictionary`2 entitySets, IDictionary`2 knownTypes)
at System.Data.Services.Providers.ObjectContextServiceProvider.PopulateMetadata(IDictionary`2 knownTypes, IDictionary`2 entitySets)
at System.Data.Services.Providers.BaseServiceProvider.PopulateMetadata()
at System.Data.Services.DataService`1.CreateProvider(Type dataServiceType, Object dataSourceInstance, DataServiceConfiguration& configuration)
at System.Data.Services.DataService`1.EnsureProviderAndConfigForRequest()
at System.Data.Services.DataService`1.ProcessRequestForMessage(Stream messageBody)
at SyncInvokeProcessRequestForMessage(Object , Object[] , Object[] )
at System.ServiceModel.Dispatcher.SyncMethodInvoker.Invoke(Object instance, Object[] inputs, Object[]& outputs)
at System.ServiceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage4(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage3(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage2(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage1(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)
</StackTrace>
<ExceptionString>System.NullReferenceException: Object reference not set to an instance of an object.
at System.Data.Services.Providers.ObjectContextServiceProvider.PopulateMemberMetadata(ResourceType resourceType, MetadataWorkspace workspace, IDictionary`2 entitySets, IDictionary`2 knownTypes)
at System.Data.Services.Providers.ObjectContextServiceProvider.PopulateMetadata(IDictionary`2 knownTypes, IDictionary`2 entitySets)
at System.Data.Services.Providers.BaseServiceProvider.PopulateMetadata()
at System.Data.Services.DataService`1.CreateProvider(Type dataServiceType, Object dataSourceInstance, DataServiceConfiguration& configuration)
at System.Data.Services.DataService`1.EnsureProviderAndConfigForRequest()
at System.Data.Services.DataService`1.ProcessRequestForMessage(Stream messageBody)
at SyncInvokeProcessRequestForMessage(Object , Object[] , Object[] )
at System.ServiceModel.Dispatcher.SyncMethodInvoker.Invoke(Object instance, Object[] inputs, Object[]& outputs)
at System.ServiceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage4(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage3(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage2(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage1(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)</ExceptionString>
</Exception>
</TraceRecord>
</DataItem>
</TraceData>
</ApplicationData>
</E2ETraceEvent>
Best Answer
I recently ran into a similar issue, and the fix in my case was changinghe the name of the EntitySetAccessRule to "*", like this: