/// <summary>Gets a string with methods allowed on the target for the <paramref name="description"/>.</summary>
/// <param name="configuration">configuration object which has the data</param>
/// <param name="description">Description with target.</param>
/// <returns>A string with methods allowed on the description; possibly null.</returns>
internal static string GetAllowedMethods(DataServiceConfiguration configuration, RequestDescription description)
{
Debug.Assert(description != null, "description != null");
Debug.Assert(
description.TargetKind != RequestTargetKind.Nothing,
"description.TargetKind != RequestTargetKind.Void - otherwise it hasn't been determined yet");
Debug.Assert(
description.TargetKind != RequestTargetKind.VoidOperation,
"description.TargetKind != RequestTargetKind.VoidOperation - this method is only for containers");
if (description.TargetKind == RequestTargetKind.Metadata ||
description.TargetKind == RequestTargetKind.ServiceDirectory)
{
return XmlConstants.HttpMethodGet;
}
if (description.TargetKind == RequestTargetKind.Batch)
{
return XmlConstants.HttpMethodPost;
}
int index = description.GetIndexOfTargetEntityResource();
Debug.Assert(index >= 0 && index < description.SegmentInfos.Count, "index >=0 && index <description.SegmentInfos.Count");
ResourceSetWrapper container = description.SegmentInfos[index].TargetResourceSet;
return GetAllowedMethods(configuration, container, description);
}
/// <summary>
/// Calls the Execution provider to invoke the request expressions for the current request
/// </summary>
/// <param name="description">Request description.</param>
/// <param name="service">Service instance.</param>
private static void InvokeRequestExpression(RequestDescription description, IDataService service)
{
Debug.Assert(description != null, "description != null");
Debug.Assert(service != null, "service != null");
HttpVerbs httpVerb = service.OperationContext.RequestMessage.HttpVerb;
bool isPostOperationRequest = httpVerb == HttpVerbs.POST && description.TargetSource == RequestTargetSource.ServiceOperation;
if (httpVerb.IsQuery() || isPostOperationRequest)
{
SegmentInfo segmentToInvoke = description.LastSegmentInfo;
if (httpVerb.IsQuery() && description.TargetSource == RequestTargetSource.Property)
{
// GET ~/Customer(1)/Address/State for example we need to execute the expression at the resource level, i.e. Customer(1).
// Then we call IDSQP.GetValue() to get the property values for Address and State.
segmentToInvoke = description.SegmentInfos[description.GetIndexOfTargetEntityResource()];
}
if (segmentToInvoke.RequestExpression != null && segmentToInvoke.RequestEnumerable == null)
{
segmentToInvoke.RequestEnumerable = service.ExecutionProvider.GetResultEnumerableFromRequest(segmentToInvoke);
}
}
}