connectors/__init__.py
author Edouard Tisserant
Tue, 23 Oct 2018 16:13:34 +0200
changeset 2322 7ce4e5cf6339
parent 2312 84b3cc18893b
child 2329 e5703dc8848e
permissions -rw-r--r--
Added runtime/spawn_subprocess.py. Force use posix spawn instead of fork, with API similar to subprocess. Using fork in runtime is incompatible with Xenomai, because memory is locked and this can lead to out of memory error.
#!/usr/bin/env python
# -*- coding: utf-8 -*-

# This file is part of Beremiz, a Integrated Development Environment for
# programming IEC 61131-3 automates supporting plcopen standard and CanFestival.
#
# Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD
# Copyright (C) 2017: Andrey Skvortsov
#
# See COPYING file for copyrights details.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

# Package initialisation


from __future__ import absolute_import
from os import listdir, path
import util.paths as paths

_base_path = paths.AbsDir(__file__)

def _GetLocalConnectorClassFactory(name):
    return lambda: getattr(__import__(name, globals(), locals()), name + "_connector_factory")


def _GetLocalConnectorClassDialog(name):
    return lambda: getattr(__import__(name + '.dialog', globals(), locals(), fromlist=['dialog']), name + "_connector_dialog")


def _GetLocalConnectorURITypes(name):
    return lambda: getattr(__import__(name + '.dialog', globals(), locals(), fromlist=['dialog']), "URITypes", None)


connectors = {name:
              _GetLocalConnectorClassFactory(name)
              for name in listdir(_base_path)
              if (path.isdir(path.join(_base_path, name)) and
                  not name.startswith("__"))}

connectors_dialog = {name:
                     {"function": _GetLocalConnectorClassDialog(name), "URITypes": _GetLocalConnectorURITypes(name)}
                     for name in listdir(_base_path)
                     if (path.isdir(path.join(_base_path, name)) and
                         not name.startswith("__"))}


def ConnectorFactory(uri, confnodesroot):
    """
    Return a connector corresponding to the URI
    or None if cannot connect to URI
    """
    servicetype = uri.split("://")[0].upper()
    if servicetype == "LOCAL":
        # Local is special case
        # pyro connection to local runtime
        # started on demand, listening on random port
        servicetype = "PYRO"
        runtime_port = confnodesroot.AppFrame.StartLocalRuntime(
            taskbaricon=True)
        uri = "PYROLOC://127.0.0.1:" + str(runtime_port)
    elif servicetype in connectors:
        pass
    elif servicetype[-1] == 'S' and servicetype[:-1] in connectors:
        servicetype = servicetype[:-1]
    else:
        return None

    # import module according to uri type
    connectorclass = connectors[servicetype]()
    return connectorclass(uri, confnodesroot)


def ConnectorDialog(conn_type, confnodesroot):
    if conn_type not in connectors_dialog:
        return None

    connectorclass = connectors_dialog[conn_type]["function"]()
    return connectorclass(confnodesroot)


def GetConnectorFromURI(uri):
    typeOfConnector = None
    for conn_type in connectors_dialog:
        connectorTypes = connectors_dialog[conn_type]["URITypes"]()
        if connectorTypes and uri in connectorTypes:
            typeOfConnector = conn_type
            break

    return typeOfConnector