Source code for tango_simlib.tango_launcher

#!/usr/bin/env python
###############################################################################
# SKA South Africa (http://ska.ac.za/)                                        #
# Author: cam@ska.ac.za                                                       #
# Copyright @ 2013 SKA SA. All rights reserved.                               #
#                                                                             #
# THIS SOFTWARE MAY NOT BE COPIED OR DISTRIBUTED IN ANY FORM WITHOUT THE      #
# WRITTEN PERMISSION OF SKA SA.                                               #
###############################################################################


"""Utility to help launch a TANGO device in a KATCP eco-system

Helps by auto-registering a TANGO device if needed

"""
import os
import sys
import argparse

import PyTango

from functools import partial

parser = argparse.ArgumentParser(
    description="Launch a TANGO device, handling registration as needed. "
    "Assumes a separate server process per device (for now?).")

required_argument = partial(parser.add_argument, required=True)

required_argument('--name', action='append',
                  help="TANGO name(s) for the devices i.e.specified multiple times",)
required_argument('--class', dest='device_class', action='append',
                  help="TANGO class name(s) for the device(s) i.e. specified the " +
                  "same number of times and the names and classes are matched in order")
required_argument('--server-command', help="TANGO server executable command")
required_argument('--server-instance', help="TANGO server instance name")
required_argument('--port', help="TCP port where TANGO server should listen")
parser.add_argument('--put-device-property', action='append', help=
                    "Put a device property into the TANGO DB, format is: "
                    "'device/name/X:property_name:property_value'. Only allows "
                    "properties to be set on devices started with this command. "
                    "Can be specified multiple times.",
                    dest='device_properties', default=[])

def register_device(name, device_class, server_name, instance):
    dev_info = PyTango.DbDevInfo()
    dev_info.name = name
    dev_info._class = device_class
    dev_info.server = "{}/{}".format(server_name.split('.')[0], instance)
    print """Attempting to register TANGO device {!r}
    class: {!r}  server: {!r}.""".format(
            dev_info.name, dev_info._class, dev_info.server)
    db = PyTango.Database()
    db.add_device(dev_info)

def put_device_property(dev_name, property_name, property_value):
    db = PyTango.Database()
    print "Setting device {!r} property {!r}: {!r}".format(
        dev_name, property_name, property_value)
    db.put_device_property(dev_name, {property_name:[property_value]})

def start_device(opts):
    server_name = os.path.basename(opts.server_command)
    number_of_devices = len(opts.name)
    #Register tango devices
    for i in range(number_of_devices):
        register_device(
            opts.name[i], opts.device_class[i], server_name, opts.server_instance)
    for dev_property in opts.device_properties:
        try:
            dev_name, dev_property_name, dev_property_val = dev_property.split(
                ':', 2)
        except ValueError:
            raise ValueError('Device property incorrectly specified, '
                             'see help for --put-device-property')
        assert dev_name in opts.name, (
            "Device {!r} not launched by this command".format(dev_name))
        put_device_property(dev_name, dev_property_name, dev_property_val)

    if '.py' in opts.server_command:
        args = ['python %s' % opts.server_command, opts.server_instance]
        print "Starting TANGO device server:\n{}".format(
              " ".join(["{!r}".format(arg) for arg in args]))
        sys.stdout.flush()
        sys.stderr.flush()
        os.system(" ".join(args))
    else:
        args = [opts.server_command,
                opts.server_instance,
               '-ORBendPoint', 'giop:tcp::{}'.format(opts.port)]
        print "Starting TANGO device server:\n{}".format(
              " ".join(["{!r}".format(arg) for arg in args]))
        sys.stdout.flush()
        sys.stderr.flush()
        os.execvp(opts.server_command, args)

def main():
    opts = parser.parse_args()
    start_device(opts)

if __name__ == '__main__':
    main()