RCUSCC.py

# -*- coding: utf-8 -*-
#
# This file is part of the RCUSCC project
#
#
#
# Distributed under the terms of the APACHE license.
# See LICENSE.txt for more info.

""" RCU-SCC Device Server for LOFAR2.0

"""

# PyTango imports
import tango
from tango import DebugIt
from tango.server import run
from tango.server import Device
from tango.server import attribute, command
from tango.server import device_property
from tango import AttrQuality, DispLevel, DevState
from tango import AttrWriteType, PipeWriteType
# Additional import
# PROTECTED REGION ID(RCUSCC.additionnal_import) ENABLED START #
import opcua
import traceback
# PROTECTED REGION END #    //  RCUSCC.additionnal_import

__all__ = ["RCUSCC", "main"]


class RCUSCC(Device):
    """

    **Properties:**

    - Device Property
        OPC_Server_Name
            - Type:'DevString'
        OPC_Server_Port
            - Type:'DevULong'
        OPC_Time_Out
            - Type:'DevDouble'
    """
    # PROTECTED REGION ID(RCUSCC.class_variable) ENABLED START #
    client = 0
    name_space_index = 0
    obj = 0
    # PROTECTED REGION END #    //  RCUSCC.class_variable

    # -----------------
    # Device Properties
    # -----------------

    OPC_Server_Name = device_property(
        dtype='DevString',
        mandatory=True
    )

    OPC_Server_Port = device_property(
        dtype='DevULong',
        mandatory=True
    )

    OPC_Time_Out = device_property(
        dtype='DevDouble',
        mandatory=True
    )

    # ----------
    # Attributes
    # ----------

    time_offset_rw = attribute(
        dtype='DevLong64',
        access=AttrWriteType.READ_WRITE,
    )

    time_offset_r = attribute(
        dtype='DevLong64',
    )

    # ---------------
    # General methods
    # ---------------

    def init_device(self):
        """Initialises the attributes and properties of the RCUSCC."""
        Device.init_device(self)
        # PROTECTED REGION ID(RCUSCC.init_device) ENABLED START #
        self.set_state(DevState.INIT)

        # Init the dict that contains attribute to OPC-UA MP/CP mappings.
        self.attribute_mapping = {}

        # Set default values in the RW/R attributes and add them to
        # the mapping.
        self._time_offset_rw = 0
        self.attribute_mapping["_time_offset_rw"] = {}
        self._time_offset_r = 0
        self.attribute_mapping["_time_offset_r"] = {}

        # Set defaults to property values.

        try:
            self.debug_stream("Connecting to OPC-UA server %s:%d...", self.OPC_Server_Name, self.OPC_Server_Port)

            self.client = opcua.Client("opc.tcp://{}:{}/".format(self.OPC_Server_Name, self.OPC_Server_Port), self.OPC_Time_Out * 1000)
            self.client.connect()
            self.debug_stream("Connecting to OPC-UA server %s:%d done.", self.OPC_Server_Name, self.OPC_Server_Port)

            try:
                self.name_space_index = self.client.get_namespace_index("http://lofar.eu")
            except Exception as e:
                self.warn_stream("Cannot determine the OPC-UA name space index.  Will try and use the default = 2.")
                self.name_space_index = 2

            self.obj_node = self.client.get_objects_node()

            self.debug_stream("Mapping OPC-UA MP/CP to attributes...")
            attribute_name = "time_offset"
            self.attribute_mapping["_time_offset_rw"] = self.obj_node.get_child([ "{}:time_offset".format(self.name_space_index),                                            "{}:time_offset_RW".format(self.name_space_index)])
            self.attribute_mapping["_time_offset_r"] = self.obj_node.get_child([ "{}:time_offset".format(self.name_space_index),                                            "{}:time_offset_R".format(self.name_space_index)])
            self.debug_stream("Mapping OPC-UA MP/CP to attributes done.")
            self.set_state(DevState.ON)
        except Exception as e:
            self.set_state(DevState.FAULT)
            self.error_stream("Connection init to the OPC-UA server %s:%d failed.  Trace: %s" % (self.OPC_Server_Name, self.OPC_Server_Port, traceback.format_exc()))
            raise e
        # PROTECTED REGION END #    //  RCUSCC.init_device

    def always_executed_hook(self):
        """Method always executed before any TANGO command is executed."""
        # PROTECTED REGION ID(RCUSCC.always_executed_hook) ENABLED START #
        # PROTECTED REGION END #    //  RCUSCC.always_executed_hook

    def delete_device(self):
        """Hook to delete resources allocated in init_device.

        This method allows for any memory or other resources allocated in the
        init_device method to be released.  This method is called by the device
        destructor and by the device Init command.
        """
        # PROTECTED REGION ID(RCUSCC.delete_device) ENABLED START #
        self.debug_stream("Shutting down...")
        self.set_state(DevState.OFF)

        if self.client is not None:
            self.client.close_session()
            self.client.close_secure_channel()
        self.debug_stream("Shut down.  Good bye.")
        # PROTECTED REGION END #    //  RCUSCC.delete_device
    # ------------------
    # Attributes methods
    # ------------------

    def read_time_offset_rw(self):
        # PROTECTED REGION ID(RCUSCC.time_offset_rw_read) ENABLED START #
        """Return the time_offset_rw attribute."""
        return self._time_offset_rw
        # PROTECTED REGION END #    //  RCUSCC.time_offset_rw_read

    def write_time_offset_rw(self, value):
        # PROTECTED REGION ID(RCUSCC.time_offset_rw_write) ENABLED START #
        """Set the time_offset_rw attribute."""
        self.attribute_mapping["_time_offset_rw"].set_value(value)
        self._time_offset_rw = value
        # PROTECTED REGION END #    //  RCUSCC.time_offset_rw_write

    def read_time_offset_r(self):
        # PROTECTED REGION ID(RCUSCC.time_offset_r_read) ENABLED START #
        """Return the time_offset_r attribute."""
        self._time_offset_r = self.attribute_mapping["_time_offset_r"].get_value()
        return self._time_offset_r
        # PROTECTED REGION END #    //  RCUSCC.time_offset_r_read

    # --------
    # Commands
    # --------

# ----------
# Run server
# ----------


def main(args=None, **kwargs):
    """Main function of the RCUSCC module."""
    # PROTECTED REGION ID(RCUSCC.main) ENABLED START #
    return run((RCUSCC,), args=args, **kwargs)
    # PROTECTED REGION END #    //  RCUSCC.main


if __name__ == '__main__':
    main()