/// <summary>
/// Browses the references from a node managed by the node manager.
/// </summary>
/// <remarks>
/// The continuation point is created for every browse operation and contains the browse parameters.
/// The node manager can store its state information in the Data and Index properties.
/// </remarks>
public virtual void Browse(
OperationContext context,
ref ContinuationPoint continuationPoint,
IList<ReferenceDescription> references)
{
if (continuationPoint == null) throw new ArgumentNullException("continuationPoint");
if (references == null) throw new ArgumentNullException("references");
ServerSystemContext systemContext = m_systemContext.Copy(context);
// check for valid view.
ValidateViewDescription(systemContext, continuationPoint.View);
INodeBrowser browser = null;
lock (Lock)
{
// check for valid handle.
NodeHandle handle = IsHandleInNamespace(continuationPoint.NodeToBrowse);
if (handle == null)
{
throw new ServiceResultException(StatusCodes.BadNodeIdUnknown);
}
// validate node.
NodeState source = ValidateNode(systemContext, handle, null);
if (source == null)
{
throw new ServiceResultException(StatusCodes.BadNodeIdUnknown);
}
// check if node is in the view.
if (!IsNodeInView(systemContext, continuationPoint, source))
{
throw new ServiceResultException(StatusCodes.BadNodeNotInView);
}
// check for previous continuation point.
browser = continuationPoint.Data as INodeBrowser;
// fetch list of references.
if (browser == null)
{
// create a new browser.
continuationPoint.Data = browser = source.CreateBrowser(
systemContext,
continuationPoint.View,
continuationPoint.ReferenceTypeId,
continuationPoint.IncludeSubtypes,
continuationPoint.BrowseDirection,
null,
null,
false);
}
}
// prevent multiple access the browser object.
lock (browser)
{
// apply filters to references.
Dictionary<NodeId, NodeState> cache = new Dictionary<NodeId, NodeState>();
for (IReference reference = browser.Next(); reference != null; reference = browser.Next())
{
// create the type definition reference.
ReferenceDescription description = GetReferenceDescription(systemContext, cache, reference, continuationPoint);
if (description == null)
{
continue;
}
// check if limit reached.
if (continuationPoint.MaxResultsToReturn != 0 && references.Count >= continuationPoint.MaxResultsToReturn)
{
browser.Push(reference);
return;
}
references.Add(description);
}
// release the continuation point if all done.
continuationPoint.Dispose();
continuationPoint = null;
}
}
/// <summary>
/// Browses the references from a node managed by the node manager.
/// </summary>
/// <remarks>
/// The continuation point is created for every browse operation and contains the browse parameters.
/// The node manager can store its state information in the Data and Index properties.
/// </remarks>
public virtual void Browse(
OperationContext context,
ref ContinuationPoint continuationPoint,
IList<ReferenceDescription> references)
{
if (continuationPoint == null) throw new ArgumentNullException("continuationPoint");
if (references == null) throw new ArgumentNullException("references");
// check for view.
if (!ViewDescription.IsDefault(continuationPoint.View))
{
throw new ServiceResultException(StatusCodes.BadViewIdUnknown);
}
ServerSystemContext systemContext = m_systemContext.Copy(context);
lock (Lock)
{
// verify that the node exists.
NodeState source = IsHandleInNamespace(continuationPoint.NodeToBrowse);
if (source == null)
{
throw new ServiceResultException(StatusCodes.BadNodeIdUnknown);
}
// validate node.
if (!ValidateNode(systemContext, source))
{
throw new ServiceResultException(StatusCodes.BadNodeIdUnknown);
}
// check for previous continuation point.
INodeBrowser browser = continuationPoint.Data as INodeBrowser;
// fetch list of references.
if (browser == null)
{
// create a new browser.
browser = source.CreateBrowser(
systemContext,
continuationPoint.View,
continuationPoint.ReferenceTypeId,
continuationPoint.IncludeSubtypes,
continuationPoint.BrowseDirection,
null,
null,
false);
}
// apply filters to references.
for (IReference reference = browser.Next(); reference != null; reference = browser.Next())
{
// create the type definition reference.
ReferenceDescription description = GetReferenceDescription(context, reference, continuationPoint);
if (description == null)
{
continue;
}
// check if limit reached.
if (continuationPoint.MaxResultsToReturn != 0 && references.Count >= continuationPoint.MaxResultsToReturn)
{
browser.Push(reference);
continuationPoint.Data = browser;
return;
}
references.Add(description);
}
// release the continuation point if all done.
continuationPoint.Dispose();
continuationPoint = null;
}
}
/// <see cref="INodeManager.Browse" />
public void Browse(
OperationContext context,
ref ContinuationPoint continuationPoint,
IList<ReferenceDescription> references)
{
if (context == null) throw new ArgumentNullException("context");
if (continuationPoint == null) throw new ArgumentNullException("continuationPoint");
if (references == null) throw new ArgumentNullException("references");
// check for valid handle.
ILocalNode source = continuationPoint.NodeToBrowse as ILocalNode;
if (source == null)
{
throw new ServiceResultException(StatusCodes.BadNodeIdUnknown);
}
// check for view.
if (!ViewDescription.IsDefault(continuationPoint.View))
{
throw new ServiceResultException(StatusCodes.BadViewIdUnknown);
}
lock (m_lock)
{
// construct list of references.
uint maxResultsToReturn = continuationPoint.MaxResultsToReturn;
// get previous enumerator.
IEnumerator<IReference> enumerator = continuationPoint.Data as IEnumerator<IReference>;
// fetch a snapshot all references for node.
if (enumerator == null)
{
List<IReference> copy = new List<IReference>(source.References);
enumerator = copy.GetEnumerator();
enumerator.MoveNext();
}
do
{
IReference reference = enumerator.Current;
// silently ignore bad values.
if (reference == null || NodeId.IsNull(reference.ReferenceTypeId) || NodeId.IsNull(reference.TargetId))
{
continue;
}
// apply browse filters.
bool include = ApplyBrowseFilters(
reference,
continuationPoint.BrowseDirection,
continuationPoint.ReferenceTypeId,
continuationPoint.IncludeSubtypes);
if (include)
{
ReferenceDescription description = new ReferenceDescription();
description.NodeId = reference.TargetId;
description.SetReferenceType(continuationPoint.ResultMask, reference.ReferenceTypeId, !reference.IsInverse);
// only fetch the metadata if it is requested.
if (continuationPoint.TargetAttributesRequired)
{
// get the metadata for the node.
NodeMetadata metadata = GetNodeMetadata(context, GetManagerHandle(reference.TargetId), continuationPoint.ResultMask);
// update description with local node metadata.
if (metadata != null)
{
description.SetTargetAttributes(
continuationPoint.ResultMask,
metadata.NodeClass,
metadata.BrowseName,
metadata.DisplayName,
metadata.TypeDefinition);
// check node class mask.
if (!CheckNodeClassMask(continuationPoint.NodeClassMask, description.NodeClass))
{
continue;
}
}
// any target that is not remote must be owned by another node manager.
else if (!reference.TargetId.IsAbsolute)
{
description.Unfiltered = true;
}
}
// add reference to list.
references.Add(description);
// construct continuation point if max results reached.
if (maxResultsToReturn > 0 && references.Count >= maxResultsToReturn)
{
continuationPoint.Index = 0;
continuationPoint.Data = enumerator;
enumerator.MoveNext();
return;
}
}
}
while (enumerator.MoveNext());
// nothing more to browse if it exits from the loop normally.
continuationPoint.Dispose();
continuationPoint = null;
}
}
