/// <summary>
/// Validates the nodes and writes the value to the underlying system.
/// </summary>
/// <param name="context">The context.</param>
/// <param name="nodesToWrite">The nodes to write.</param>
/// <param name="errors">The errors.</param>
/// <param name="nodesToValidate">The nodes to validate.</param>
/// <param name="cache">The cache.</param>
protected override void Write(
ServerSystemContext context,
IList <WriteValue> nodesToWrite,
IList <ServiceResult> errors,
List <NodeHandle> nodesToValidate,
IDictionary <NodeId, NodeState> cache)
{
ComDaClientManager system = (ComDaClientManager)this.SystemContext.SystemHandle;
ComDaClient client = system.SelectClient((ServerSystemContext)SystemContext, false);
WriteRequestCollection requests = new WriteRequestCollection();
// validates the nodes and queues an write requests.
for (int ii = 0; ii < nodesToValidate.Count; ii++)
{
NodeHandle handle = nodesToValidate[ii];
lock (Lock)
{
// validate node.
NodeState source = ValidateNode(context, handle, cache);
if (source == null)
{
continue;
}
// determine if request can be sent to the server.
bool queued = false;
WriteValue nodeToWrite = nodesToWrite[handle.Index];
errors[handle.Index] = requests.Add(source, nodeToWrite, handle.Index, out queued);
if (queued)
{
continue;
}
// write the attribute value.
errors[handle.Index] = source.WriteAttribute(
context,
nodeToWrite.AttributeId,
nodeToWrite.ParsedIndexRange,
nodeToWrite.Value);
// updates to source finished - report changes to monitored items.
source.ClearChangeMasks(context, false);
}
}
// write to the server.
client.Write(requests);
// get the results from the requests sent to the server.
for (int ii = 0; ii < requests.Count; ii++)
{
WriteRequest request = requests[ii];
errors[request.Index] = request.GetResult();
}
}
/// <summary>
/// Handles a write operation.
/// </summary>
protected override void Write(
ServerSystemContext context,
IList <WriteValue> nodesToWrite,
IList <ServiceResult> errors,
List <NodeHandle> nodesToValidate,
IDictionary <NodeId, NodeState> cache)
{
List <ReadWriteRequest> requests = new List <ReadWriteRequest>();
// validates the nodes and constructs requests for external nodes.
for (int ii = 0; ii < nodesToValidate.Count; ii++)
{
WriteValue nodeToWrite = nodesToWrite[ii];
NodeHandle handle = nodesToValidate[ii];
lock (Lock)
{
// validate node.
NodeState source = ValidateNode(context, handle, cache);
if (source == null)
{
continue;
}
// determine if an external source is required.
if (IsExternalSource(handle, nodeToWrite.AttributeId))
{
errors[handle.Index] = AddWriteRequest(context, handle, nodeToWrite, requests);
continue;
}
// write the attribute value.
errors[handle.Index] = source.WriteAttribute(
context,
nodeToWrite.AttributeId,
nodeToWrite.ParsedIndexRange,
nodeToWrite.Value);
// updates to source finished - report changes to monitored items.
source.ClearChangeMasks(context, false);
}
}
// send request to external system.
try
{
ProcessWriteRequests(requests);
}
catch (Exception e)
{
// handle unexpected communication error.
ServiceResult error = ServiceResult.Create(e, StatusCodes.BadUnexpectedError, "Could not access external system.");
for (int ii = 0; ii < requests.Count; ii++)
{
requests[ii].Result = error;
}
}
// set results.
for (int ii = 0; ii < requests.Count; ii++)
{
ReadWriteRequest request = requests[ii];
errors[request.Handle.Index] = request.Result;
}
}
