Example #1
0
        /// <summary>
        /// Collects the fields for the instance node.
        /// </summary>
        /// <param name="session">The session.</param>
        /// <param name="nodeId">The node id.</param>
        /// <param name="parentPath">The parent path.</param>
        /// <param name="fields">The event fields.</param>
        /// <param name="fieldNodeIds">The node id for the declaration of the field.</param>
        /// <param name="foundNodes">The table of found nodes.</param>
        private static void CollectFields(
            Session session,
            NodeId nodeId,
            QualifiedNameCollection parentPath,
            SimpleAttributeOperandCollection fields,
            List <NodeId> fieldNodeIds,
            Dictionary <NodeId, QualifiedNameCollection> foundNodes)
        {
            // find all of the children of the field.
            BrowseDescription nodeToBrowse = new BrowseDescription();

            nodeToBrowse.NodeId          = nodeId;
            nodeToBrowse.BrowseDirection = BrowseDirection.Forward;
            nodeToBrowse.ReferenceTypeId = ReferenceTypeIds.Aggregates;
            nodeToBrowse.IncludeSubtypes = true;
            nodeToBrowse.NodeClassMask   = (uint)(NodeClass.Object | NodeClass.Variable);
            nodeToBrowse.ResultMask      = (uint)BrowseResultMask.All;

            ReferenceDescriptionCollection children = FormUtils.Browse(session, nodeToBrowse, false);

            if (children == null)
            {
                return;
            }

            // process the children.
            for (int ii = 0; ii < children.Count; ii++)
            {
                ReferenceDescription child = children[ii];

                if (child.NodeId.IsAbsolute)
                {
                    continue;
                }

                // construct browse path.
                QualifiedNameCollection browsePath = new QualifiedNameCollection(parentPath);
                browsePath.Add(child.BrowseName);

                // check if the browse path is already in the list.
                int index = ContainsPath(fields, browsePath);

                if (index < 0)
                {
                    SimpleAttributeOperand field = new SimpleAttributeOperand();

                    field.TypeDefinitionId = ObjectTypeIds.BaseEventType;
                    field.BrowsePath       = browsePath;
                    field.AttributeId      = (child.NodeClass == NodeClass.Variable) ? Attributes.Value : Attributes.NodeId;

                    fields.Add(field);
                    fieldNodeIds.Add((NodeId)child.NodeId);
                }

                // recusively find all of the children.
                NodeId targetId = (NodeId)child.NodeId;

                // need to guard against loops.
                if (!foundNodes.ContainsKey(targetId))
                {
                    foundNodes.Add(targetId, browsePath);
                    CollectFields(session, (NodeId)child.NodeId, browsePath, fields, fieldNodeIds, foundNodes);
                }
            }
        }
Example #2
0
        /// <summary>
        /// Constructs an event object from a notification.
        /// </summary>
        /// <param name="session">The session.</param>
        /// <param name="monitoredItem">The monitored item that produced the notification.</param>
        /// <param name="notification">The notification.</param>
        /// <param name="knownEventTypes">The known event types.</param>
        /// <param name="eventTypeMappings">Mapping between event types and known event types.</param>
        /// <returns>
        /// The event object. Null if the notification is not a valid event type.
        /// </returns>
        public static BaseEventState ConstructEvent(
            Session session,
            MonitoredItem monitoredItem,
            EventFieldList notification,
            Dictionary <NodeId, Type> knownEventTypes,
            Dictionary <NodeId, NodeId> eventTypeMappings)
        {
            // find the event type.
            NodeId eventTypeId = FindEventType(monitoredItem, notification);

            if (eventTypeId == null)
            {
                return(null);
            }

            // look up the known event type.
            Type   knownType   = null;
            NodeId knownTypeId = null;

            if (eventTypeMappings.TryGetValue(eventTypeId, out knownTypeId))
            {
                knownType = knownEventTypes[knownTypeId];
            }

            // try again.
            if (knownType == null)
            {
                if (knownEventTypes.TryGetValue(eventTypeId, out knownType))
                {
                    knownTypeId = eventTypeId;
                    eventTypeMappings.Add(eventTypeId, eventTypeId);
                }
            }

            // try mapping it to a known type.
            if (knownType == null)
            {
                // browse for the supertypes of the event type.
                ReferenceDescriptionCollection supertypes = FormUtils.BrowseSuperTypes(session, eventTypeId, false);

                // can't do anything with unknown types.
                if (supertypes == null)
                {
                    return(null);
                }

                // find the first supertype that matches a known event type.
                for (int ii = 0; ii < supertypes.Count; ii++)
                {
                    NodeId superTypeId = (NodeId)supertypes[ii].NodeId;

                    if (knownEventTypes.TryGetValue(superTypeId, out knownType))
                    {
                        knownTypeId = superTypeId;
                        eventTypeMappings.Add(eventTypeId, superTypeId);
                    }

                    if (knownTypeId != null)
                    {
                        break;
                    }
                }

                // can't do anything with unknown types.
                if (knownTypeId == null)
                {
                    return(null);
                }
            }

            // construct the event based on the known event type.
            BaseEventState e = (BaseEventState)Activator.CreateInstance(knownType, new object[] { (NodeState)null });

            // get the filter which defines the contents of the notification.
            EventFilter filter = monitoredItem.Status.Filter as EventFilter;

            // initialize the event with the values in the notification.
            e.Update(session.SystemContext, filter.SelectClauses, notification);

            // save the orginal notification.
            e.Handle = notification;

            return(e);
        }