/// <summary>
/// If the provider implements IConcurrencyProvider, then this method passes the etag values
/// to the provider, otherwise compares the etag itself.
/// </summary>
/// <param name="resourceCookie">etag values for the given resource.</param>
/// <param name="container">container for the given resource.</param>
internal void SetETagValues(object resourceCookie, ResourceSetWrapper container)
{
Debug.Assert(resourceCookie != null, "resourceCookie != null");
Debug.Assert(container != null, "container != null");
AstoriaRequestMessage host = this.service.OperationContext.RequestMessage;
Debug.Assert(String.IsNullOrEmpty(host.GetRequestIfNoneMatchHeader()), "IfNoneMatch header cannot be specified for Update/Delete operations");
// Resolve the cookie first to the actual resource type
object actualEntity = this.ResolveResource(resourceCookie);
Debug.Assert(actualEntity != null, "actualEntity != null");
ResourceType resourceType = WebUtil.GetNonPrimitiveResourceType(this.service.Provider, actualEntity);
Debug.Assert(resourceType != null, "resourceType != null");
IList <ResourceProperty> etagProperties = this.service.Provider.GetETagProperties(container.Name, resourceType);
if (etagProperties.Count == 0)
{
if (!String.IsNullOrEmpty(host.GetRequestIfMatchHeader()))
{
throw DataServiceException.CreateBadRequestError(Strings.Serializer_NoETagPropertiesForType);
}
// If the type has no etag properties, then we do not need to do any etag checks
return;
}
// If the provider implements IConcurrencyProvider, then we need to call the provider
// and pass the etag values. Else, we need to compare the etag values ourselves.
IDataServiceUpdateProvider concurrencyProvider = this.updateProvider as IDataServiceUpdateProvider;
if (concurrencyProvider != null)
{
bool?checkForEquality = null;
IEnumerable <KeyValuePair <string, object> > etagValues;
if (!String.IsNullOrEmpty(host.GetRequestIfMatchHeader()))
{
checkForEquality = true;
etagValues = ParseETagValue(etagProperties, host.GetRequestIfMatchHeader());
}
else
{
etagValues = WebUtil.EmptyKeyValuePairStringObject;
}
concurrencyProvider.SetConcurrencyValues(resourceCookie, checkForEquality, etagValues);
}
else if (String.IsNullOrEmpty(host.GetRequestIfMatchHeader()))
{
throw DataServiceException.CreateBadRequestError(Strings.DataService_CannotPerformOperationWithoutETag(resourceType.FullName));
}
else if (host.GetRequestIfMatchHeader() != XmlConstants.HttpAnyETag)
{
// Compare If-Match header value with the current etag value, if the If-Match header value is not equal to '*'
string etagValue = WebUtil.GetETagValue(resourceCookie, resourceType, etagProperties, this.service, false /*getMethod*/);
Debug.Assert(!String.IsNullOrEmpty(etagValue), "etag value can never be null");
if (etagValue != host.GetRequestIfMatchHeader())
{
throw DataServiceException.CreatePreConditionFailedError(Strings.Serializer_ETagValueDoesNotMatch);
}
}
}
