//======================================================================
// GetStatus
/// <summary>
/// Returns the current server status.
/// </summary>
/// <returns>The current server status.</returns>
public ServerStatus GetStatus()
{
lock (this)
{
if (m_proxy == null)
{
throw new NotConnectedException();
}
OpcXml.Da10.RequestOptions options = OpcXml.Da10.Request.GetRequestOptions(m_options.Locale, m_options.Filters);
OpcXml.Da10.ServerStatus remoteStatus = null;
OpcXml.Da10.ReplyBase reply = m_proxy.GetStatus(
options.LocaleID,
options.ClientRequestHandle,
out remoteStatus);
CacheResponse(m_options.Locale, reply, null);
// fill in the last update time.
ServerStatus status = OpcXml.Da10.Request.GetServerStatus(reply, remoteStatus);
status.LastUpdateTime = m_lastUpdateTime;
return(status);
}
}
/// <summary>
/// Returns the locales supported by the server
/// </summary>
/// <remarks>The first element in the array must be the default locale for the server.</remarks>
/// <returns>An array of locales with the format "[languagecode]-[country/regioncode]".</returns>
public string[] GetSupportedLocales()
{
lock (this)
{
if (m_proxy == null)
{
throw new NotConnectedException();
}
OpcXml.Da10.ServerStatus status = null;
OpcXml.Da10.ReplyBase reply = m_proxy.GetStatus(
m_options.Locale,
null,
out status);
if (status != null && status.SupportedLocaleIDs != null)
{
ArrayList locales = new ArrayList();
foreach (string locale in status.SupportedLocaleIDs)
{
if (locale != null)
{
locales.Add(locale);
}
}
return((string[])locales.ToArray(typeof(string)));
}
return(null);
}
}
//======================================================================
// Write
/// <summary>
/// Writes the value, quality and timestamp for a set of items.
/// </summary>
/// <param name="items">The set of item values to write.</param>
/// <returns>The results of the write operation for each item.</returns>
public IdentifiedResult[] Write(ItemValue[] items)
{
if (items == null)
{
throw new ArgumentNullException("items");
}
if (items.Length == 0)
{
return(new Opc.IdentifiedResult[0]);
}
lock (this)
{
if (m_proxy == null)
{
throw new NotConnectedException();
}
ItemValueList list = new ItemValueList();
list.AddRange(items);
OpcXml.Da10.RequestOptions options = OpcXml.Da10.Request.GetRequestOptions(m_options.Locale, m_options.Filters);
OpcXml.Da10.WriteRequestItemList requestList = OpcXml.Da10.Request.GetItemValueList(list);
OpcXml.Da10.ReplyItemList replyList = null;
OpcXml.Da10.OPCError[] errors = null;
OpcXml.Da10.ReplyBase reply = m_proxy.Write(
options,
requestList,
false,
out replyList,
out errors);
CacheResponse(m_options.Locale, reply, errors);
ItemValueResultList valueList = OpcXml.Da10.Request.GetResultList(replyList);
if (valueList == null)
{
throw new InvalidResponseException();
}
IdentifiedResult[] results = new IdentifiedResult[valueList.Count];
for (int ii = 0; ii < valueList.Count; ii++)
{
ItemValueResult valueResult = valueList[ii];
results[ii] = new IdentifiedResult(valueResult);
results[ii].ResultID = valueResult.ResultID;
results[ii].DiagnosticInfo = valueResult.DiagnosticInfo;
}
return(results);
}
}
/// <summary>
/// Called when a subscription receives a polled refresh response.
/// </summary>
internal void PollCompleted(
string localeID,
OpcXml.Da10.ReplyBase reply,
OpcXml.Da10.OPCError[] errors)
{
lock (this)
{
CacheResponse(localeID, reply, errors);
m_lastUpdateTime = reply.ReplyTime;
}
}
//======================================================================
// BrowseNext
/// <summary>
/// Continues a browse operation with previously specified search criteria.
/// </summary>
/// <param name="position">An object containing the browse operation state information.</param>
/// <returns>The set of elements found.</returns>
public BrowseElement[] BrowseNext(ref Opc.Da.BrowsePosition position)
{
if (position == null)
{
throw new ArgumentNullException("position");
}
if (m_proxy == null)
{
throw new NotConnectedException();
}
lock (this)
{
BrowsePosition pos = (BrowsePosition)position;
if (pos.ContinuationPoint == null || pos.ContinuationPoint == "")
{
throw new BrowseCannotContinueException();
}
OpcXml.Da10.BrowseElement[] elements = null;
OpcXml.Da10.OPCError[] errors = null;
OpcXml.Da10.ReplyBase reply = m_proxy.Browse(
OpcXml.Da10.Request.GetPropertyNames(pos.Filters.PropertyIDs),
pos.Locale,
"",
(pos.ItemID != null)?pos.ItemID.ItemPath:null,
(pos.ItemID != null)?pos.ItemID.ItemName:null,
ref pos.ContinuationPoint,
pos.Filters.MaxElementsReturned,
OpcXml.Da10.Request.GetBrowseFilter(pos.Filters.BrowseFilter),
pos.Filters.ElementNameFilter,
pos.Filters.VendorFilter,
pos.Filters.ReturnAllProperties,
pos.Filters.ReturnPropertyValues,
pos.ReturnErrorText,
out elements,
out errors,
out pos.MoreElements);
CacheResponse(pos.Locale, reply, errors);
position = null;
if (pos.MoreElements || (pos.ContinuationPoint != null && pos.ContinuationPoint != ""))
{
position = pos;
}
return(OpcXml.Da10.Request.GetBrowseElements(elements));
}
}
//======================================================================
// Browse
/// <summary>
/// Fetches the children of a branch that meet the filter criteria.
/// </summary>
/// <param name="itemID">The identifier of branch which is the target of the search.</param>
/// <param name="filters">The filters to use to limit the set of child elements returned.</param>
/// <param name="position">An object used to continue a browse that could not be completed.</param>
/// <returns>The set of elements found.</returns>
public BrowseElement[] Browse(
ItemIdentifier itemID,
BrowseFilters filters,
out Opc.Da.BrowsePosition position)
{
position = null;
lock (this)
{
if (m_proxy == null)
{
throw new NotConnectedException();
}
// use default filters if none specified.
if (filters == null)
{
filters = new BrowseFilters();
}
BrowsePosition pos = new BrowsePosition(itemID, filters, m_options.Locale, ((m_options.Filters & (int)ResultFilter.ErrorText) != 0));
OpcXml.Da10.BrowseElement[] elements = null;
OpcXml.Da10.OPCError[] errors = null;
OpcXml.Da10.ReplyBase reply = m_proxy.Browse(
OpcXml.Da10.Request.GetPropertyNames(filters.PropertyIDs),
pos.Locale,
"",
(itemID != null)?itemID.ItemPath:null,
(itemID != null)?itemID.ItemName:null,
ref pos.ContinuationPoint,
filters.MaxElementsReturned,
OpcXml.Da10.Request.GetBrowseFilter(filters.BrowseFilter),
filters.ElementNameFilter,
filters.VendorFilter,
filters.ReturnAllProperties,
filters.ReturnPropertyValues,
pos.ReturnErrorText,
out elements,
out errors,
out pos.MoreElements);
CacheResponse(pos.Locale, reply, errors);
if (pos.MoreElements || (pos.ContinuationPoint != null && pos.ContinuationPoint != ""))
{
position = pos;
}
return(OpcXml.Da10.Request.GetBrowseElements(elements));
}
}
//======================================================================
// Read
/// <summary>
/// Reads the current values for a set of items.
/// </summary>
/// <param name="items">The set of items to read.</param>
/// <returns>The results of the read operation for each item.</returns>
public Opc.Da.ItemValueResult[] Read(Item[] items)
{
if (items == null)
{
throw new ArgumentNullException("items");
}
if (items.Length == 0)
{
return(new Opc.Da.ItemValueResult[0]);
}
lock (this)
{
if (m_proxy == null)
{
throw new NotConnectedException();
}
ItemList list = new ItemList();
list.AddRange(items);
OpcXml.Da10.RequestOptions options = OpcXml.Da10.Request.GetRequestOptions(m_options.Locale, m_options.Filters);
OpcXml.Da10.ReadRequestItemList requestList = OpcXml.Da10.Request.GetItemList(list);
OpcXml.Da10.ReplyItemList replyList = null;
OpcXml.Da10.OPCError[] errors = null;
OpcXml.Da10.ReplyBase reply = m_proxy.Read(
options,
requestList,
out replyList,
out errors);
CacheResponse(m_options.Locale, reply, errors);
ItemValueResultList valueList = OpcXml.Da10.Request.GetResultList(replyList);
if (valueList == null)
{
throw new InvalidResponseException();
}
return((ItemValueResult[])valueList.ToArray(typeof(ItemValueResult)));
}
}
//======================================================================
// Private Methods
/// <summary>
/// Caches error messages and request statistics after each request.
/// </summary>
internal void CacheResponse(
string locale,
OpcXml.Da10.ReplyBase reply,
OpcXml.Da10.OPCError[] errors)
{
lock (this)
{
if (reply != null)
{
// check for revised locale id.
if (reply.RevisedLocaleID != null)
{
locale = reply.RevisedLocaleID;
}
// calculate the bias to use when calculating request timeouts.
m_timebias = reply.ReplyTime.Subtract(DateTime.Now);
}
if (errors != null && errors.Length > 0)
{
// check for null locale.
if (locale == null)
{
locale = "";
}
// find the message table for the locale.
Hashtable messageTable = (Hashtable)m_messageTables[locale];
if (messageTable == null)
{
m_messageTables[locale] = messageTable = new Hashtable();
}
// index message texts by message id.
foreach (OpcXml.Da10.OPCError error in errors)
{
messageTable[OpcXml.Da10.Request.GetResultID(error.ID)] = error.Text;
}
}
}
}
//======================================================================
// GetProperties
/// <summary>
/// Returns the item properties for a set of items.
/// </summary>
/// <param name="itemIDs">A list of item identifiers.</param>
/// <param name="propertyIDs">A list of properties to fetch for each item.</param>
/// <param name="returnValues">Whether the property values should be returned with the properties.</param>
/// <returns>A list of properties for each item.</returns>
public ItemPropertyCollection[] GetProperties(
ItemIdentifier[] itemIDs,
PropertyID[] propertyIDs,
bool returnValues)
{
if (itemIDs == null)
{
throw new ArgumentNullException("itemIDs");
}
if (m_proxy == null)
{
throw new NotConnectedException();
}
lock (this)
{
OpcXml.Da10.RequestOptions options = OpcXml.Da10.Request.GetRequestOptions(m_options.Locale, m_options.Filters);
OpcXml.Da10.PropertyReplyList[] properties = null;
OpcXml.Da10.OPCError[] errors = null;
OpcXml.Da10.ReplyBase reply = m_proxy.GetProperties(
OpcXml.Da10.Request.GetItemIdentifiers(itemIDs),
OpcXml.Da10.Request.GetPropertyNames(propertyIDs),
options.LocaleID,
options.ClientRequestHandle,
null,
(propertyIDs == null),
returnValues,
options.ReturnErrorText,
out properties,
out errors);
CacheResponse(options.LocaleID, reply, errors);
return(OpcXml.Da10.Request.GetItemPropertyCollections(properties));
}
}
/// <summary>
/// Establishes a subscription for the current set of items.
/// </summary>
private ItemValueResultList Subscribe(ArrayList items)
{
lock (this)
{
// cancel any current subscription.
Unsubscribe();
// check if there is nothing to do.
if (items == null || items.Count == 0)
{
return(new ItemValueResultList());
}
// create a single item list and use the subscription state to set list level parameters.
ItemList itemList = new ItemList();
itemList.ClientHandle = Guid.NewGuid().ToString();
itemList.ItemPath = null;
itemList.ReqType = null;
itemList.Deadband = m_state.Deadband;
itemList.DeadbandSpecified = true;
itemList.SamplingRate = m_state.UpdateRate;
itemList.SamplingRateSpecified = true;
itemList.EnableBuffering = false;
itemList.EnableBufferingSpecified = false;
// set the ping rate based on the keep alive (if specified) or five times update rate.
m_pingRate = (m_state.KeepAlive != 0)?m_state.KeepAlive:m_state.UpdateRate * 5;
// stop any existing timer.
if (m_pollTimer != null)
{
m_pollTimer.Dispose();
m_pollTimer = null;
}
// create copies of each and replace the client handle with the server handle.
foreach (Item item in items)
{
Item clone = (Item)item.Clone();
clone.ClientHandle = clone.ServerHandle;
itemList.Add(clone);
}
string subscription = null;
// establish the subscription on the server.
OpcXml.Da10.RequestOptions options = OpcXml.Da10.Request.GetRequestOptions(m_state.Locale, m_filters);
OpcXml.Da10.SubscribeReplyItemList replyList = null;
OpcXml.Da10.OPCError[] errors = null;
OpcXml.Da10.ReplyBase reply = m_proxy.Subscribe(
options,
OpcXml.Da10.Request.GetSubscribeList(itemList),
true,
m_pingRate * 2,
out replyList,
out errors,
out subscription);
// cache results with the server object.
m_server.CacheResponse(m_state.Locale, reply, errors);
// save subscription handle.
m_state.ServerHandle = subscription;
// check for valid response.
if (replyList == null)
{
throw new InvalidResponseException();
}
// save the revised update rate.
if (replyList.RevisedSamplingRateSpecified)
{
m_state.UpdateRate = (int)replyList.RevisedSamplingRate;
}
// update items.
ItemValueResultList resultList = OpcXml.Da10.Request.GetSubscribeResultList(replyList);
for (int ii = 0; ii < itemList.Count; ii++)
{
SubscribeItemValueResult resultItem = (SubscribeItemValueResult)resultList[ii];
// restore the client/server handles in the result.
resultItem.ServerHandle = resultItem.ClientHandle;
resultItem.ClientHandle = ((Item)items[ii]).ClientHandle;
// check if the requested sampling rate was accepted.
if (!resultItem.SamplingRateSpecified)
{
resultItem.SamplingRate = itemList[ii].SamplingRate;
resultItem.SamplingRateSpecified = itemList[ii].SamplingRateSpecified;
}
}
// schedule polling.
SchedulePoll();
// return result list.
return(resultList);
}
}
/// <summary>
/// Called when a poll completes.
/// </summary>
private void OnPollCompleted(IAsyncResult handle)
{
// restore async state parameters.
string[] args = (string[])handle.AsyncState;
try
{
lock (this)
{
// check if object has been disposed.
if (m_proxy == null)
{
return;
}
// fetch the poll results.
string[] invalidHandles = null;
bool bufferOverflow = false;
OpcXml.Da10.SubscribePolledRefreshReplyItemList[] replyLists = null;
OpcXml.Da10.OPCError[] errors = null;
OpcXml.Da10.ReplyBase reply = null;
reply = m_proxy.EndSubscriptionPolledRefresh(
handle,
out invalidHandles,
out replyLists,
out errors,
out bufferOverflow);
// cache results with the server object.
m_server.PollCompleted((string)args[1], reply, errors);
// check if the server handle has changed - ignore results in this case.
if (!args[0].Equals(m_state.ServerHandle))
{
return;
}
ItemValueResultList resultList = null;
// restore subscription if it has been dropped by the server for some reason.
if (invalidHandles != null && invalidHandles.Length > 0)
{
resultList = Subscribe(m_items);
if (resultList != null && resultList.Count == m_items.Count)
{
// replace the client handles.
for (int ii = 0; ii < m_items.Count; ii++)
{
SubscribeItemValueResult result = (SubscribeItemValueResult)resultList[ii];
if (result.ResultID.Succeeded())
{
Item item = (Item)m_items[ii];
// save revised sampling rate.
item.SamplingRate = result.SamplingRate;
item.SamplingRateSpecified = result.SamplingRateSpecified;
}
}
}
}
// get the list of changed items.
else
{
ItemValueResultList[] resultLists = OpcXml.Da10.Request.GetSubscribeRefreshLists(replyLists);
// validate items and replace the client handles.
resultList = new ItemValueResultList();
if (resultLists != null && resultLists.Length == 1)
{
foreach (ItemValueResult result in resultLists[0])
{
foreach (Item item in m_items)
{
if (item.ServerHandle.Equals(result.ClientHandle))
{
result.ServerHandle = item.ServerHandle;
result.ClientHandle = item.ClientHandle;
resultList.Add(result);
break;
}
}
}
}
}
// send the data change notifications.
OnDataChange(resultList);
// check if a new poll should be scheduled.
if (args[2] != null)
{
SchedulePoll();
}
}
}
catch (Exception e)
{
string message = e.Message;
// schedule a new poll on exception.
if (args[2] != null)
{
SchedulePoll();
}
}
}
