model_variable.cpp

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/******************************************************************************
 *   Copyright (C) 2013-2014 by Alexander Rykovanov                        *
 *   rykovanov.as@gmail.com                                                   *
 *                                                                            *
 *   This library is free software; you can redistribute it and/or modify     *
 *   it under the terms of the GNU Lesser General Public License as           *
 *   published by the Free Software Foundation; version 3 of the License.     *
 *                                                                            *
 *   This library is distributed in the hope that it will be useful,          *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of           *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the            *
 *   GNU Lesser General Public License for more details.                      *
 *                                                                            *
 *   You should have received a copy of the GNU Lesser General Public License *
 *   along with this library; if not, write to the                            *
 *   Free Software Foundation, Inc.,                                          *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.                *
 ******************************************************************************/

#include "model_impl.h"

#include <opc/ua/model.h>

namespace OpcUa
{
namespace Model
{
Variable::Variable(NodeId variableId, Services::SharedPtr services)
  : Node(services)
{
  Id = variableId;
  ReadParameters attrs;
  attrs.AttributesToRead.push_back(ToReadValueId(variableId, AttributeId::DisplayName));
  attrs.AttributesToRead.push_back(ToReadValueId(variableId, AttributeId::BrowseName));
  attrs.AttributesToRead.push_back(ToReadValueId(variableId, AttributeId::DataType));
  std::vector<DataValue> values = services->Attributes()->Read(attrs);
  DisplayName = values[0].Value.As<LocalizedText>();
  BrowseName = values[1].Value.As<QualifiedName>();
  DataType = OpcUa::DataTypeToVariantType(values[2].Value.As<NodeId>());
}

DataValue Variable::GetValue() const
{
  ReadParameters params;
  params.AttributesToRead.push_back(ToReadValueId(GetId(), AttributeId::Value));
  const std::vector<DataValue> result = GetServices()->Attributes()->Read(params);

  if (result.size() != 1)
    {
      throw std::runtime_error("Cannot read variable value. Server returned invalid number of values.");
    }

  return result.front();
}

void Variable::SetValue(const Variant & value)
{
  DataValue data(value);
  data.SetSourceTimestamp(OpcUa::DateTime::Current());
  SetValue(data);
}

void Variable::SetValue(const DataValue & value)
{
  WriteValue writeValue;
  writeValue.AttributeId = AttributeId::Value;
  writeValue.Value = value;
  writeValue.NodeId = Id;
  std::vector<StatusCode> result = GetServices()->Attributes()->Write({writeValue});

  if (result.size() != 1)
    {
      throw std::runtime_error("Failed to write data. Server returned wron nunber of status codes.");
    }

  CheckStatusCode(result[0]);
}

std::vector<Variable> Variable::Variables() const
{
  return Browse<Variable>(GetId(), NodeClass::Variable, GetServices());
}
}
}