private object GetMarshalledParameter(DataServiceOperationContext operationContext, ServiceActionParameter serviceActionParameter, object value)
{
var parameterKind = serviceActionParameter.ParameterType.ResourceTypeKind;
// Need to Marshall MultiValues i.e. Collection(Primitive) & Collection(ComplexType)
if (parameterKind == ResourceTypeKind.EntityType)
{
// This entity is UNATTACHED. But people are likely to want to edit this...
IDataServiceUpdateProvider2 updateProvider = operationContext.GetService(typeof(IDataServiceUpdateProvider2)) as IDataServiceUpdateProvider2;
value = updateProvider.GetResource(value as IQueryable, serviceActionParameter.ParameterType.InstanceType.FullName);
value = updateProvider.ResolveResource(value); // This will attach the entity.
}
else if (parameterKind == ResourceTypeKind.EntityCollection)
{
// WCF Data Services constructs an IQueryable that is NoTracking...
// but that means people can't just edit the entities they pull from the Query.
var query = value as ObjectQuery;
query.MergeOption = MergeOption.AppendOnly;
}
else if (parameterKind == ResourceTypeKind.Collection)
{
// need to coerce into a List<> for dispatch
var enumerable = value as IEnumerable;
// the <T> in List<T> is the Instance type of the ItemType
var elementType = (serviceActionParameter.ParameterType as CollectionResourceType).ItemType.InstanceType;
// call IEnumerable.Cast<T>();
var castMethod = CastMethodGeneric.MakeGenericMethod(elementType);
object marshalledValue = castMethod.Invoke(null, new[] { enumerable });
// call IEnumerable<T>.ToList();
var toListMethod = ToListMethodGeneric.MakeGenericMethod(elementType);
value = toListMethod.Invoke(null, new[] { marshalledValue });
}
return(value);
}
/// <summary>
/// Constructs a delegate to invoke the service action with the provided parameters.
/// </summary>
/// <param name="operationContext">The data service operation context instance.</param>
/// <param name="dataService">The data service instance.</param>
/// <param name="action">The service action to invoke.</param>
/// <param name="parameters">The parameters required to invoke the service action.</param>
private void ConstructInvokeDelegateForServiceAction(DataServiceOperationContext operationContext, ServiceAction action, object[] parameters)
{
var info = action.CustomState as DSPServiceActionInfo;
if (info == null)
{
throw new InvalidOperationException("Insufficient information to invoke the service action!");
}
IDataServiceUpdateProvider2 updateProvider = (IDataServiceUpdateProvider2)operationContext.GetService(typeof(IDataServiceUpdateProvider2));
if (updateProvider == null)
{
throw new InvalidOperationException("DataServiceOperationContext.GetService(IDataServiceUpdateProvider2) returned null!");
}
this.invokeDelegate = () =>
{
int idx = 0;
if (action.BindingParameter != null)
{
if (action.BindingParameter.ParameterType.ResourceTypeKind == ResourceTypeKind.EntityType)
{
parameters[idx] = updateProvider.GetResource((IQueryable)parameters[idx], null);
}
parameters[idx] = updateProvider.ResolveResource(parameters[idx]);
idx++;
}
var methodParameters = info.Method.GetParameters();
for (; idx < parameters.Length; idx++)
{
ServiceActionParameter sap = action.Parameters[idx];
if (sap.ParameterType.ResourceTypeKind == ResourceTypeKind.Collection && parameters[idx] != null)
{
ResourceType itemResourceType = ((CollectionResourceType)sap.ParameterType).ItemType;
// Need to call ResolveResource on each complex item in the collection.
Type parameterType = methodParameters[idx].ParameterType;
Type itemType = parameterType.GetGenericArguments()[0];
MethodInfo resolveCollectionMethod;
if (parameterType.GetGenericTypeDefinition() == typeof(IQueryable <>))
{
resolveCollectionMethod = DSPInvokableAction.ResolveCollectionAsQueryableMethodInfo.MakeGenericMethod(itemType);
}
else
{
resolveCollectionMethod = DSPInvokableAction.ResolveCollectionMethodInfo.MakeGenericMethod(itemType);
}
parameters[idx] = resolveCollectionMethod.Invoke(null, new object[] { updateProvider, parameters[idx], itemResourceType.ResourceTypeKind == ResourceTypeKind.Primitive });
}
else if (sap.ParameterType.ResourceTypeKind == ResourceTypeKind.ComplexType)
{
parameters[idx] = updateProvider.ResolveResource(parameters[idx]);
}
}
this.result = info.Method.Invoke(info.Instance, parameters);
};
}