/// <summary>
/// Saves the element in cache.
/// </summary>
/// <param name="element">The element.</param>
private void SaveElementInCache(DaElement element)
{
lock (m_cache)
{
m_cache[element.ItemId] = element;
}
}
/// <summary>
/// Finds the element and updates the name if it is not already cached.
/// </summary>
/// <param name="itemId">The item id.</param>
/// <param name="name">The name.</param>
/// <param name="parentId">The parent id.</param>
/// <returns>The element.</returns>
private DaElement FindElement(string itemId, string name, string parentId)
{
if (String.IsNullOrEmpty(itemId))
{
return(null);
}
// look in cache for existing element.
DaElement element = null;
lock (m_cache)
{
if (!m_cache.TryGetValue(itemId, out element))
{
element = null;
}
}
// create a new element.
if (element == null)
{
element = CreateElement(itemId, name, parentId);
SaveElementInCache(element);
}
// update the element.
element.Name = name;
element.ParentId = parentId;
return(element);
}
/// <summary>
/// Creates a new element.
/// </summary>
/// <param name="itemId">The item id.</param>
/// <param name="name">The name.</param>
/// <param name="parentId">The parent id.</param>
/// <returns>The element.</returns>
private DaElement CreateElement(string itemId, string name, string parentId)
{
DaElement element = new DaElement();
element.ItemId = itemId;
UpdateElement(element, name, parentId);
return(element);
}
/// <summary>
/// Constructs a branch or item node from a DaElement returned from the COM server.
/// </summary>
/// <param name="context">The context.</param>
/// <param name="element">The element.</param>
/// <param name="namespaceIndex">Index of the namespace for the NodeId.</param>
/// <returns>The node.</returns>
public static NodeState ConstructElement(ISystemContext context, DaElement element, ushort namespaceIndex)
{
if (element.ElementType == DaElementType.Branch)
{
return(new DaBranchState(context, element, namespaceIndex));
}
return(new DaItemState(context, element, namespaceIndex));
}
/// <summary>
/// Finds the property metadata for the specified item id.
/// </summary>
/// <param name="itemId">The item id.</param>
/// <param name="propertyId">The property id.</param>
/// <returns>The metadata for the property.</returns>
public DaProperty FindProperty(string itemId, int propertyId)
{
if (String.IsNullOrEmpty(itemId))
{
return(null);
}
// check the cache.
DaElement element = null;
lock (m_cache)
{
if (m_cache.TryGetValue(itemId, out element))
{
if (element.Properties != null)
{
for (int ii = 0; ii < element.Properties.Length; ii++)
{
if (element.Properties[ii].PropertyId == propertyId)
{
return(element.Properties[ii]);
}
}
}
}
}
// check if the element has to be loaded.
if (element == null)
{
element = FindElement(itemId);
if (element == null)
{
return(null);
}
}
// update the property list.
element.Properties = ReadAvailableProperties(itemId, false);
if (element.Properties != null)
{
for (int ii = 0; ii < element.Properties.Length; ii++)
{
if (element.Properties[ii].PropertyId == propertyId)
{
return(element.Properties[ii]);
}
}
}
// not found.
return(null);
}
/// <summary>
/// Initializes the node from the element.
/// </summary>
/// <param name="context">The context.</param>
/// <param name="element">The element.</param>
/// <param name="namespaceIndex">Index of the namespace.</param>
public void Initialize(ISystemContext context, DaElement element, ushort namespaceIndex)
{
m_element = element;
if (element == null)
{
return;
}
this.NodeId = ModelUtils.ConstructIdForDaElement(element.ItemId, -1, namespaceIndex);
this.BrowseName = new QualifiedName(element.Name, namespaceIndex);
this.DisplayName = new LocalizedText(element.Name);
}
/// <summary>
/// Initializes a new instance of the <see cref="DaItemState"/> class.
/// </summary>
/// <param name="context">The context.</param>
/// <param name="element">The element.</param>
/// <param name="namespaceIndex">Index of the namespace.</param>
public DaItemState(
ISystemContext context,
DaElement element,
ushort namespaceIndex)
:
base(null)
{
this.TypeDefinitionId = Opc.Ua.VariableTypeIds.DataItemType;
this.Description = null;
this.WriteMask = 0;
this.UserWriteMask = 0;
if (element != null)
{
Initialize(context, element, namespaceIndex);
}
}
/// <summary>
/// Finds the item id for the parent of the element.
/// </summary>
/// <param name="itemId">The item id.</param>
/// <returns>The item id for the parent of the element.</returns>
public string FindElementParentId(string itemId)
{
if (String.IsNullOrEmpty(itemId))
{
return(null);
}
// check in cache.
DaElement element = null;
lock (m_cache)
{
if (m_cache.TryGetValue(itemId, out element))
{
if (element.ParentId != null)
{
return(element.ParentId);
}
}
}
// try extracting the name by parsing the item id.
string name = null;
string parentId = null;
if (ParseItemId(itemId, out name, out parentId))
{
element = CreateElement(itemId, name, parentId);
}
// need to do it the hard way by searching the address space.
else
{
IDaElementBrowser browser = CreateBrowser(itemId);
element = browser.Find(itemId, false);
browser.Dispose();
}
// save element in the cache.
if (element != null)
{
SaveElementInCache(element);
}
return(element.ParentId);
}
/// <summary>
/// Initializes a new instance of the <see cref="DaBranchState"/> class.
/// </summary>
/// <param name="context">The context.</param>
/// <param name="element">The element.</param>
/// <param name="namespaceIndex">Index of the namespace.</param>
public DaBranchState(
ISystemContext context,
DaElement element,
ushort namespaceIndex)
:
base(null)
{
this.TypeDefinitionId = Opc.Ua.ObjectTypeIds.FolderType;
this.Description = null;
this.WriteMask = 0;
this.UserWriteMask = 0;
this.EventNotifier = EventNotifiers.None;
if (element != null)
{
Initialize(context, element, namespaceIndex);
}
}
/// <summary>
/// Initializes a new instance of the <see cref="DaBranchState"/> class.
/// </summary>
/// <param name="context">The context.</param>
/// <param name="element">The element.</param>
/// <param name="namespaceIndex">Index of the namespace.</param>
public DaBranchState(
ISystemContext context,
DaElement element,
ushort namespaceIndex)
:
base(null)
{
this.TypeDefinitionId = Opc.Ua.ObjectTypeIds.FolderType;
this.Description = null;
this.WriteMask = 0;
this.UserWriteMask = 0;
this.EventNotifier = EventNotifiers.None;
if (element != null)
{
Initialize(context, element, namespaceIndex);
}
}
/// <summary>
/// Initializes the node from the element.
/// </summary>
/// <param name="context">The context.</param>
/// <param name="element">The element.</param>
/// <param name="namespaceIndex">Index of the namespace.</param>
public void Initialize(ISystemContext context, DaElement element, ushort namespaceIndex)
{
m_element = element;
if (element == null)
{
return;
}
this.NodeId = ModelUtils.ConstructIdForDaElement(element.ItemId, -1, namespaceIndex);
this.BrowseName = new QualifiedName(element.Name, namespaceIndex);
this.DisplayName = new LocalizedText(element.Name);
}
/// <summary>
/// Finds the element with the specified item id.
/// </summary>
/// <param name="parentId">The parent id.</param>
/// <param name="targetId">The target id.</param>
/// <param name="isItem">if set to <c>true</c> the element is a item.</param>
/// <param name="recursive">if set to <c>true</c> [recursive].</param>
/// <returns>The element if found.</returns>
public DaElement Find(string parentId, string targetId, bool isItem, bool recursive)
{
// create the enumerator if not already created.
m_enumerator = m_clone.CreateEnumerator(false);
// a null indicates an error.
if (m_enumerator == null)
{
return(null);
}
string name = null;
// process all items.
do
{
// fetch the next name.
name = m_enumerator.Next();
// a null indicates the end of list.
if (name == null)
{
break;
}
// fetch the item id.
string itemId = m_clone.GetItemId(name);
// fetch the metadata.
DaElement element = m_client.FindElement(itemId, name, parentId);
// check if target found.
if (targetId == itemId)
{
return(element);
}
}while (true);
m_enumerator.Dispose();
m_enumerator = null;
List <DaElement> branches = new List <DaElement>();
// fetch the branches of the target is a branch or if a recursive search is required.
if (!isItem || recursive)
{
// need to fetch list of branches to search.
m_enumerator = m_clone.CreateEnumerator(true);
if (m_enumerator == null)
{
return(null);
}
// process all branches.
do
{
name = m_enumerator.Next();
// a null indicates the end of list.
if (name == null)
{
break;
}
// fetch the item id.
string itemId = m_clone.GetItemId(name);
// fetch the metadata.
DaElement element = m_client.FindElement(itemId, name, parentId);
// save branch for recursive search if not found at this level.
if (recursive)
{
branches.Add(element);
}
// check if target found.
if (targetId == itemId)
{
return(element);
}
}while (name != null);
m_enumerator.Dispose();
m_enumerator = null;
}
// all done if not doing a recursive search.
if (!recursive)
{
return(null);
}
// recursively search hierarchy.
for (int ii = 0; ii < branches.Count; ii++)
{
m_clone.ChangeBrowsePosition(OPCBROWSEDIRECTION.OPC_BROWSE_DOWN, branches[ii].Name);
DaElement element = Find(branches[ii].ItemId, targetId, isItem, recursive);
if (element != null)
{
return(element);
}
m_clone.ChangeBrowsePosition(OPCBROWSEDIRECTION.OPC_BROWSE_UP, String.Empty);
}
// not found.
return(null);
}
/// <summary>
/// Returns the next child.
/// </summary>
private NodeStateReference NextChild(Stage stage)
{
ComDaClientManager system = (ComDaClientManager)this.SystemContext.SystemHandle;
ComDaClient client = system.SelectClient((ServerSystemContext)SystemContext);
DaElement element = null;
if (stage == Stage.Children)
{
if (m_browser == null)
{
return(null);
}
element = m_browser.Next();
if (element == null)
{
return(null);
}
// construct the node.
NodeState node = ModelUtils.ConstructElement(SystemContext, element, m_namespaceIndex);
// return the reference.
return(new NodeStateReference(ReferenceTypeIds.Organizes, false, node));
}
if (stage == Stage.Properties)
{
if (m_properties == null)
{
return(null);
}
for (int ii = m_position; ii < m_properties.Length; ii++)
{
if (m_properties[ii].PropertyId <= PropertyIds.TimeZone)
{
continue;
}
m_position = ii + 1;
// construct the node.
NodeState node = ModelUtils.ConstructProperty(SystemContext, m_itemId, m_properties[ii], m_namespaceIndex);
// return the reference.
return(new NodeStateReference(ReferenceTypeIds.HasProperty, false, node));
}
// all done.
return(null);
}
if (stage == Stage.Parents)
{
if (m_parentId != null)
{
NodeId parentId = ModelUtils.ConstructIdForDaElement(m_parentId, -1, m_namespaceIndex);
m_parentId = null;
return(new NodeStateReference(ReferenceTypeIds.Organizes, true, parentId));
}
}
return(null);
}
/// <summary>
/// Initializes the node from the element.
/// </summary>
/// <param name="context">The context.</param>
/// <param name="element">The element.</param>
/// <param name="namespaceIndex">Index of the namespace.</param>
public void Initialize(ISystemContext context, DaElement element, ushort namespaceIndex)
{
m_element = element;
if (element == null)
{
return;
}
this.NodeId = ModelUtils.ConstructIdForDaElement(element.ItemId, -1, namespaceIndex);
this.BrowseName = new QualifiedName(element.Name, namespaceIndex);
this.DisplayName = new LocalizedText(element.Name);
// check if TimeZone is supported.
if (element.TimeZone != null)
{
PropertyState property = this.AddProperty <Range>(Opc.Ua.BrowseNames.TimeZone, DataTypeIds.TimeZoneDataType, ValueRanks.Scalar);
property.NodeId = ModelUtils.ConstructIdForComponent(property, namespaceIndex);
property.Value = new Range(element.HighIR, element.LowIR);
}
// set the TypeDefinition based on the ElementType.
switch (element.ElementType)
{
case DaElementType.AnalogItem:
{
this.TypeDefinitionId = Opc.Ua.VariableTypeIds.AnalogItemType;
// EURange is always present.
PropertyState property = this.AddProperty <Range>(Opc.Ua.BrowseNames.EURange, DataTypeIds.Range, ValueRanks.Scalar);
property.NodeId = ModelUtils.ConstructIdForComponent(property, namespaceIndex);
property.Value = new Range(element.HighEU, element.LowEU);
// check if InstrumentRange is supported.
if (element.HighIR != 0 || element.LowIR != 0)
{
property = this.AddProperty <Range>(Opc.Ua.BrowseNames.InstrumentRange, DataTypeIds.Range, ValueRanks.Scalar);
property.NodeId = ModelUtils.ConstructIdForComponent(property, namespaceIndex);
property.Value = new Range(element.HighIR, element.LowIR);
}
// check if EngineeringUnits is supported.
if (element.EngineeringUnits != null)
{
property = this.AddProperty <EUInformation>(Opc.Ua.BrowseNames.EngineeringUnits, DataTypeIds.EUInformation, ValueRanks.Scalar);
property.NodeId = ModelUtils.ConstructIdForComponent(property, namespaceIndex);
// use the server's namespace uri to qualify the engineering units.
string namespaceUri = context.NamespaceUris.GetString(namespaceIndex);
property.Value = new EUInformation(element.EngineeringUnits, namespaceUri);
}
break;
}
case DaElementType.DigitalItem:
{
this.TypeDefinitionId = Opc.Ua.VariableTypeIds.TwoStateDiscreteType;
this.EnumStrings = new PropertyState <LocalizedText[]>(this);
// check if CloseLabel is supported.
if (element.CloseLabel != null)
{
PropertyState property = this.AddProperty <LocalizedText>(Opc.Ua.BrowseNames.TrueState, DataTypeIds.LocalizedText, ValueRanks.Scalar);
property.NodeId = ModelUtils.ConstructIdForComponent(property, namespaceIndex);
property.Value = element.CloseLabel;
}
// check if OpenLabel is supported.
if (element.OpenLabel != null)
{
PropertyState property = this.AddProperty <LocalizedText>(Opc.Ua.BrowseNames.FalseState, DataTypeIds.LocalizedText, ValueRanks.Scalar);
property.NodeId = ModelUtils.ConstructIdForComponent(property, namespaceIndex);
property.Value = element.OpenLabel;
}
break;
}
case DaElementType.EnumeratedItem:
{
this.TypeDefinitionId = Opc.Ua.VariableTypeIds.MultiStateDiscreteType;
// check if EuInfo is supported.
if (element.EuInfo != null)
{
PropertyState property = this.AddProperty <LocalizedText[]>(Opc.Ua.BrowseNames.EnumStrings, DataTypeIds.LocalizedText, ValueRanks.OneDimension);
property.NodeId = ModelUtils.ConstructIdForComponent(property, namespaceIndex);
LocalizedText[] strings = new LocalizedText[element.EuInfo.Length];
for (int ii = 0; ii < strings.Length; ii++)
{
strings[ii] = element.EuInfo[ii];
}
property.Value = strings;
}
break;
}
}
if (element.Description != null)
{
this.Description = element.Description;
}
this.Value = null;
this.StatusCode = StatusCodes.BadWaitingForInitialData;
this.Timestamp = DateTime.UtcNow;
bool isArray = false;
this.DataType = ComUtils.GetDataTypeId(element.DataType, out isArray);
this.ValueRank = (isArray)?ValueRanks.OneOrMoreDimensions:ValueRanks.Scalar;
this.AccessLevel = AccessLevels.None;
if ((element.AccessRights & OpcRcw.Da.Constants.OPC_READABLE) != 0)
{
this.AccessLevel |= AccessLevels.CurrentRead;
}
if ((element.AccessRights & OpcRcw.Da.Constants.OPC_WRITEABLE) != 0)
{
this.AccessLevel |= AccessLevels.CurrentWrite;
}
this.UserAccessLevel = this.AccessLevel;
this.MinimumSamplingInterval = element.ScanRate;
}
/// <summary>
/// Returns the next DA element.
/// </summary>
/// <returns>A DA element. Null if nothing left to browse.</returns>
public DaElement Next()
{
// check if already completed.
if (m_completed)
{
return(null);
}
// create the enumerator if not already created.
if (m_enumerator == null)
{
// need to clone the client since ChangeBrowsePosition prevents multiple
// simultaneous browse operations.
m_clone = m_client.CloneClient();
m_clone.CreateInstance();
// nothing to browse if change browse position failed.
if (!m_clone.ChangeBrowsePosition(OPCBROWSEDIRECTION.OPC_BROWSE_TO, m_itemId))
{
return(null);
}
m_enumerator = m_clone.CreateEnumerator(false);
m_branches = false;
// a null indicates an error.
if (m_enumerator == null)
{
m_completed = true;
return(null);
}
}
// need a loop in case errors occur fetching element metadata.
DaElement element = null;
do
{
// fetch the next name.
string name = m_enumerator.Next();
// a null indicates the end of list.
if (name == null)
{
if (!m_branches)
{
m_branches = true;
m_enumerator.Dispose();
m_enumerator = m_clone.CreateEnumerator(true);
continue;
}
m_completed = true;
return(null);
}
// suppress duplicates when a item is also a branch.
if (m_branches)
{
if (m_itemNames != null)
{
if (m_itemNames.ContainsKey(name))
{
continue;
}
}
}
// save the item name to allow checks for duplicates.
else
{
if (m_itemNames == null)
{
m_itemNames = new Dictionary <string, object>();
}
m_itemNames[name] = null;
}
// fetch the item id.
string itemId = m_clone.GetItemId(name);
// fetch the metadata.
element = m_client.FindElement(itemId, name, m_itemId);
}while (element == null);
// return element.
return(element);
}
/// <summary>
/// Updates a element.
/// </summary>
/// <param name="element">The element.</param>
/// <param name="name">The name.</param>
/// <param name="parentId">The parent id.</param>
private void UpdateElement(DaElement element, string name, string parentId)
{
// only update the name if specified.
if (name != null)
{
element.Name = name;
}
// same for the parent id.
if (parentId != null)
{
element.ParentId = parentId;
}
// read item property values.
DaValue[] values = ReadPropertyValues(element.ItemId, m_CoreProperties);
// must be an item if the data type property exists.
if (values[0].Error >= 0)
{
element.ElementType = DaElementType.Item;
element.DataType = values[0].GetValue <short>();
element.AccessRights = values[1].GetValue <int>();
element.ScanRate = values[2].GetValue <float>();
element.Description = values[3].GetValue <string>();
element.EngineeringUnits = values[4].GetValue <string>();
element.EuInfo = values[5].GetValue <string[]>();
element.EuType = values[6].GetValue <int>();
element.HighEU = values[7].GetValue <double>();
element.LowEU = values[8].GetValue <double>();
element.OpenLabel = values[9].GetValue <string>();
element.CloseLabel = values[10].GetValue <string>();
element.HighIR = values[11].GetValue <double>();
element.LowIR = values[12].GetValue <double>();
// check if the time zone is specified.
if (values[13].Error >= 0)
{
element.TimeZone = values[13].GetValue <int>();
}
// check for analog item (checks for HighEU if EuType property not supported).
if ((values[7].Error < 0 && values[7].Error >= 0) || element.EuType == (int)OPCEUTYPE.OPC_ANALOG)
{
element.ElementType = DaElementType.AnalogItem;
}
// check for enumerated item.
else if (element.EuType == (int)OPCEUTYPE.OPC_ENUMERATED)
{
element.ElementType = DaElementType.EnumeratedItem;
}
// check for digital item (checks for CloseLabel property).
else if (values[10].Error >= 0)
{
element.ElementType = DaElementType.DigitalItem;
}
}
// the element must be a branch.
else
{
element.ElementType = DaElementType.Branch;
// branches could have description property.
element.Description = values[3].GetValue <string>();
}
}
/// <summary>
/// Read the available non-built in properties from the server.
/// </summary>
/// <param name="itemId">The item id.</param>
/// <param name="updateCache">if set to <c>true</c> the cache is updated.</param>
/// <returns>The array of properties.</returns>
public DaProperty[] ReadAvailableProperties(string itemId, bool updateCache)
{
string methodName = "IOPCItemProperties.QueryAvailableProperties";
// query for available properties.
int count = 0;
IntPtr pPropertyIds = IntPtr.Zero;
IntPtr pDescriptions = IntPtr.Zero;
IntPtr pDataTypes = IntPtr.Zero;
try
{
IOPCItemProperties server = BeginComCall <IOPCItemProperties>(methodName, true);
server.QueryAvailableProperties(
itemId,
out count,
out pPropertyIds,
out pDescriptions,
out pDataTypes);
}
catch (Exception e)
{
if (ComUtils.IsUnknownError(e, ResultIds.E_FAIL, ResultIds.E_UNKNOWNITEMID, ResultIds.E_INVALIDITEMID))
{
ComUtils.TraceComError(e, methodName);
}
return(null);
}
finally
{
EndComCall(methodName);
}
// unmarshal results.
int[] propertyIds = ComUtils.GetInt32s(ref pPropertyIds, count, true);
string[] descriptions = ComUtils.GetUnicodeStrings(ref pDescriptions, count, true);
short[] datatype = ComUtils.GetInt16s(ref pDataTypes, count, true);
List <DaProperty> properties = new List <DaProperty>();
for (int ii = 0; ii < count; ii++)
{
// do not return any of the built in properties.
if (propertyIds[ii] <= PropertyIds.TimeZone)
{
continue;
}
DaProperty property = new DaProperty();
property.PropertyId = propertyIds[ii];
property.Name = descriptions[ii];
property.DataType = datatype[ii];
properties.Add(property);
}
// fetch the item ids.
if (properties.Count > 0)
{
DaProperty[] array = properties.ToArray();
GetPropertyItemIds(itemId, array);
// update the cache.
if (updateCache)
{
lock (m_cache)
{
DaElement element = null;
if (m_cache.TryGetValue(itemId, out element))
{
element.Properties = array;
}
}
}
return(array);
}
return(null);
}
