/// <summary>response materialization has an identity to attach to the inserted object</summary>
/// <param name="entityDescriptorFromMaterializer">entity descriptor containing all the information about the entity from the response.</param>
/// <param name="metadataMergeOption">mergeOption based on which EntityDescriptor will be merged.</param>
internal override void AttachIdentity(EntityDescriptor entityDescriptorFromMaterializer, MergeOption metadataMergeOption)
{ // insert->unchanged
Debug.Assert(entityDescriptorFromMaterializer != null, "entityDescriptorFromMaterializer != null");
this.EnsureIdentityToResource();
// resource.State == EntityState.Added or Unchanged for second pass of media link
EntityDescriptor trackedEntityDescriptor = this.entityDescriptors[entityDescriptorFromMaterializer.Entity];
// make sure we got the right one - server could override identity and we may be tracking another one already.
this.ValidateDuplicateIdentity(entityDescriptorFromMaterializer.Identity, trackedEntityDescriptor);
this.DetachResourceIdentity(trackedEntityDescriptor);
// While processing the response, we need to find out if the given resource was inserted deep
// If it was, then we need to change the link state from added to unchanged
if (trackedEntityDescriptor.IsDeepInsert)
{
LinkDescriptor end = this.bindings[trackedEntityDescriptor.GetRelatedEnd()];
end.State = EntityStates.Unchanged;
}
trackedEntityDescriptor.Identity = entityDescriptorFromMaterializer.Identity; // always attach the identity
AtomMaterializerLog.MergeEntityDescriptorInfo(trackedEntityDescriptor, entityDescriptorFromMaterializer, true /*mergeInfo*/, metadataMergeOption);
trackedEntityDescriptor.State = EntityStates.Unchanged;
trackedEntityDescriptor.PropertiesToSerialize.Clear();
// scenario: successfully (1) delete an existing entity and (2) add a new entity where the new entity has the same identity as deleted entity
// where the SaveChanges pass1 will now associate existing identity with new entity
// but pass2 for the deleted entity will not blindly remove the identity that is now associated with the new identity
this.identityToDescriptor[entityDescriptorFromMaterializer.Identity] = trackedEntityDescriptor;
}
/// <summary>Applies all accumulated changes to the associated data context.</summary>
/// <remarks>The log should be cleared after this method successfully executed.</remarks>
internal void ApplyToContext()
{
if (!this.Tracking)
{
return;
}
foreach (KeyValuePair <Uri, ODataResource> entity in this.identityStack)
{
// Try to attach the entity descriptor got from materializer, if one already exists, get the existing reference instead.
MaterializerEntry entry = MaterializerEntry.GetEntry(entity.Value);
bool mergeEntityDescriptorInfo = entry.CreatedByMaterializer ||
entry.ResolvedObject == this.insertRefreshObject ||
entry.ShouldUpdateFromPayload;
// Whenever we merge the data, only at those times will be merge the links also
EntityDescriptor descriptor = this.entityTracker.InternalAttachEntityDescriptor(entry.EntityDescriptor, false /*failIfDuplicated*/);
AtomMaterializerLog.MergeEntityDescriptorInfo(descriptor, entry.EntityDescriptor, mergeEntityDescriptorInfo, this.mergeOption);
if (mergeEntityDescriptorInfo)
{
// In AtomMaterializer.TryResolveFromContext, we set AtomEntry.ShouldUpdateFromPayload to true
// when even MergeOption is PreserveChanges and entityState is Deleted. But in that case, we cannot
// set the entity state to Unchanged, hence need to workaround that one scenario
if (this.mergeOption != MergeOption.PreserveChanges || descriptor.State != EntityStates.Deleted)
{
// we should always reset descriptor's state to Unchanged (old v1 behavior)
descriptor.State = EntityStates.Unchanged;
descriptor.PropertiesToSerialize.Clear();
}
}
}
foreach (LinkDescriptor link in this.links)
{
if (EntityStates.Added == link.State)
{
// Added implies collection
this.entityTracker.AttachLink(link.Source, link.SourceProperty, link.Target, this.mergeOption);
}
else if (EntityStates.Modified == link.State)
{
// Modified implies reference
object target = link.Target;
if (MergeOption.PreserveChanges == this.mergeOption)
{
// GetLinks looks up the existing link using just the SourceProperty, the declaring server type name is not significant here.
LinkDescriptor end = this.entityTracker.GetLinks(link.Source, link.SourceProperty).SingleOrDefault();
if (end != null && end.Target == null)
{
// leave the SetLink(link.Source, link.SourceProperty, null)
continue;
}
if ((target != null) && (this.entityTracker.GetEntityDescriptor(target).State == EntityStates.Deleted) ||
(EntityStates.Deleted == this.entityTracker.GetEntityDescriptor(link.Source).State))
{
target = null;
}
}
this.entityTracker.AttachLink(link.Source, link.SourceProperty, target, this.mergeOption);
}
else
{
// detach link
Debug.Assert(EntityStates.Detached == link.State, "not detached link");
this.entityTracker.DetachExistingLink(link, false);
}
}
}