bacpypes/samples/ReadPropertyJSON.py

#!/usr/bin/env python

"""
This application presents a 'console' prompt to the user asking for read
commands which create ReadPropertyRequest PDUs, then lines up the
coorresponding ReadPropertyACK and prints the value.

This version uses the --json option for settings, BACpypes.json rather than
BACpypes.ini.
"""

import sys

from bacpypes.debugging import bacpypes_debugging, ModuleLogger
from bacpypes.consolelogging import JSONArgumentParser, ConsoleLogHandler
from bacpypes.consolecmd import ConsoleCmd

from bacpypes.core import run, deferred, enable_sleeping
from bacpypes.iocb import IOCB

from bacpypes.pdu import Address
from bacpypes.apdu import ReadPropertyRequest, ReadPropertyACK
from bacpypes.primitivedata import Unsigned, ObjectIdentifier
from bacpypes.constructeddata import Array

from bacpypes.app import BIPSimpleApplication
from bacpypes.object import get_datatype
from bacpypes.local.device import LocalDeviceObject

# some debugging
_debug = 0
_log = ModuleLogger(globals())

# globals
this_application = None


#
#   ReadPropertyConsoleCmd
#


@bacpypes_debugging
class ReadPropertyConsoleCmd(ConsoleCmd):
    def do_read(self, args):
        """read <addr> <objid> <prop> [ <indx> ]"""
        args = args.split()
        if _debug:
            ReadPropertyConsoleCmd._debug("do_read %r", args)

        try:
            addr, obj_id, prop_id = args[:3]
            obj_id = ObjectIdentifier(obj_id).value
            if prop_id.isdigit():
                prop_id = int(prop_id)

            datatype = get_datatype(obj_id[0], prop_id)
            if not datatype:
                raise ValueError("invalid property for object type")

            # build a request
            request = ReadPropertyRequest(
                objectIdentifier=obj_id, propertyIdentifier=prop_id
            )
            request.pduDestination = Address(addr)

            if len(args) == 4:
                request.propertyArrayIndex = int(args[3])
            if _debug:
                ReadPropertyConsoleCmd._debug("    - request: %r", request)

            # make an IOCB
            iocb = IOCB(request)
            if _debug:
                ReadPropertyConsoleCmd._debug("    - iocb: %r", iocb)

            # give it to the application
            deferred(this_application.request_io, iocb)

            # wait for it to complete
            iocb.wait()

            # do something for error/reject/abort
            if iocb.ioError:
                sys.stdout.write(str(iocb.ioError) + "\n")

            # do something for success
            elif iocb.ioResponse:
                apdu = iocb.ioResponse

                # should be an ack
                if not isinstance(apdu, ReadPropertyACK):
                    if _debug:
                        ReadPropertyConsoleCmd._debug("    - not an ack")
                    return

                # find the datatype
                datatype = get_datatype(
                    apdu.objectIdentifier[0], apdu.propertyIdentifier
                )
                if _debug:
                    ReadPropertyConsoleCmd._debug("    - datatype: %r", datatype)
                if not datatype:
                    raise TypeError("unknown datatype")

                # special case for array parts, others are managed by cast_out
                if issubclass(datatype, Array) and (
                    apdu.propertyArrayIndex is not None
                ):
                    if apdu.propertyArrayIndex == 0:
                        value = apdu.propertyValue.cast_out(Unsigned)
                    else:
                        value = apdu.propertyValue.cast_out(datatype.subtype)
                else:
                    value = apdu.propertyValue.cast_out(datatype)
                if _debug:
                    ReadPropertyConsoleCmd._debug("    - value: %r", value)

                sys.stdout.write(str(value) + "\n")
                if hasattr(value, "debug_contents"):
                    value.debug_contents(file=sys.stdout)
                sys.stdout.flush()

            # do something with nothing?
            else:
                if _debug:
                    ReadPropertyConsoleCmd._debug(
                        "    - ioError or ioResponse expected"
                    )

        except Exception as error:
            ReadPropertyConsoleCmd._exception("exception: %r", error)

    def do_rtn(self, args):
        """rtn <addr> <net> ... """
        args = args.split()
        if _debug:
            ReadPropertyConsoleCmd._debug("do_rtn %r", args)

        # provide the address and a list of network numbers
        router_address = Address(args[0])
        network_list = [int(arg) for arg in args[1:]]

        # pass along to the service access point
        this_application.nsap.update_router_references(
            None, router_address, network_list
        )


#
#   __main__
#


def main():
    global this_application

    # create a console log handler to show how settings are gathered from
    # the JSON file.  The settings may include debugging, so this is to
    # debug the debugging and usually isn't necessary
    ConsoleLogHandler("bacpypes.consolelogging")

    # parse the command line arguments
    args = JSONArgumentParser(description=__doc__).parse_args()

    if _debug:
        _log.debug("initialization")
    if _debug:
        _log.debug("    - args: %r", args)

    local_device = args.json["local-device"]
    if _debug:
        _log.debug("    - local_device: %r", local_device)

    # make a device object
    this_device = LocalDeviceObject(**local_device)
    if _debug:
        _log.debug("    - this_device: %r", this_device)

    # make a simple application
    this_application = BIPSimpleApplication(this_device, local_device.address)

    # make a console
    this_console = ReadPropertyConsoleCmd()
    if _debug:
        _log.debug("    - this_console: %r", this_console)

    # enable sleeping will help with threads
    enable_sleeping()

    _log.debug("running")

    run()

    _log.debug("fini")


if __name__ == "__main__":
    main()