Steep learning curve

[mcondarelli]

Hi,
first and foremost: Thanks for all the good work.

I'm trying to use dbussy/ravel to interface ConnMan.
Since I'm new to all of them: ConnMan, D-Bus and Your code, there's little surprise in me having problems, sorry.

I am trying to do things stepwise and I have the following test code:

#!/usr/bin/python3

import asyncio
import ravel

import pprint
from logging import getLogger
log = getLogger('networks')
pp = pprint.PrettyPrinter(indent=4)

bus_name = "net.connman"
path_name = "/"
iface_name = "net.connman.Manager"
chime_signal_name = "chime"

loop = asyncio.get_event_loop()


bus = ravel.system_bus()
bus.attach_asyncio(loop)
server = loop.run_until_complete(bus.get_proxy_interface_async(destination=bus_name,
                                                               path="/",
                                                               interface=iface_name))
server = server(connection=bus.connection, dest=bus_name)


async def main():
    print('===================================')
    tl = await server['/'].GetTechnologies()
    for p in tl[0]:
        # pp.pprint(p)
        print('-----------------------------------')
        print(f'-- {p[1]["Name"][1]}: {p[0]} --')
    print('===================================')
    sl = await server['/'].GetServices()
    for p in sl[0]:
        # pp.pprint(p)
        print('-----------------------------------')
        print(f'-- {p[1]["Name"][1]}: {p[0]} --')
    print('===================================')
    for p in tl[0]:
        pp.pprint(p)
        if p[1]['Type'][1] == 'wifi':
            print('-----------------------------------')
            t = p[1]
            print(f'-- {t["Name"][1]}: {p[0]} --')
            s = bus.get_proxy_interface(bus_name,  p[0], 'net.connman.Technology')
            s(connection=bus.connection, dest='net.connman.Technology').Scan()
            await asyncio.sleep(10)
    print('===================================')
    sl = await server['/'].GetServices()
    for p in sl[0]:
        # pp.pprint(p)
        print('-----------------------------------')
        print(f'-- {p[1]["Name"][1]}: {p[0]} --')
    print('===================================')


loop.run_until_complete(main())

This code, mostly stealed from useless_managed_object_server_ravelled, results in an exception:

===================================
-----------------------------------
-- Wired: /net/connman/technology/ethernet --
-----------------------------------
-- WiFi: /net/connman/technology/wifi --
-----------------------------------
-- Bluetooth: /net/connman/technology/bluetooth --
===================================
-----------------------------------
-- NETGEAR_11AC: /net/connman/service/wifi_001500d77076_4e4554474541525f31314143_managed_psk --
-----------------------------------
-- Wired: /net/connman/service/ethernet_02693694c027_cable --
-----------------------------------
-- Wired: /net/connman/service/ethernet_723575276940_cable --
-----------------------------------
-- Wired: /net/connman/service/ethernet_ae8d48867953_cable --
-----------------------------------
-- Wired: /net/connman/service/ethernet_ba6926867953_cable --
-----------------------------------
-- Wired: /net/connman/service/ethernet_366cdd276940_cable --
===================================
[   ObjectPath('/net/connman/technology/ethernet'),
    {   'Connected': (Signature('b'), True),
        'Name': (Signature('s'), 'Wired'),
        'Powered': (Signature('b'), True),
        'Tethering': (Signature('b'), False),
        'Type': (Signature('s'), 'ethernet')}]
[   ObjectPath('/net/connman/technology/wifi'),
    {   'Connected': (Signature('b'), True),
        'Name': (Signature('s'), 'WiFi'),
        'Powered': (Signature('b'), True),
        'Tethering': (Signature('b'), False),
        'Type': (Signature('s'), 'wifi')}]
-----------------------------------
-- WiFi: /net/connman/technology/wifi --
Traceback (most recent call last):
  File "/home/mcon/projects/dbussy/networks.py", line 78, in <module>
    loop.run_until_complete(main())
  File "/usr/lib/python3.7/asyncio/base_events.py", line 583, in run_until_complete
    return future.result()
  File "/home/mcon/projects/dbussy/networks.py", line 67, in main
    s(connection=bus.connection, dest='net.connman.Technology').Scan()
AttributeError: 'net.connman.Technology_factory' object has no attribute 'Scan'

Process finished with exit code 1

Reference code I'm trying to convert to ravel is:

    technology = dbus.Interface(bus.get_object("net.connman", 
                                               "/net/connman/technology/wifi"),
                                "net.connman.Technology")
    technology.Scan()

What am I doing so wrong?
Thanks in Advance
Mauro

[ldo]

Note that the proxy interface needs an object path, e.g.

s(connection=bus.connection, dest='net.connman.Technology')['/net/connman/technology/wifi'].Scan()

(Not sure if that exact path will work. Try running the introspect_all example script to see more details about that daemon’s object model.)

[mcondarelli]

Thanks for the quick answer.

./introspect_all system net.connman returns:

<!DOCTYPE node PUBLIC "-//freedesktop//DTD D-BUS Object Introspection 1.0//EN"
"http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd">
<node name="/">
    <interface name="org.freedesktop.DBus.Introspectable">
        <method name="Introspect">
            <arg name="xml" type="s" direction="out"/>
        </method>
    </interface>
    <interface name="net.connman.Manager">
        <method name="GetProperties">
            <arg name="properties" type="a{sv}" direction="out"/>
        </method>
        <method name="SetProperty">
            <arg name="name" type="s" direction="in"/>
            <arg name="value" type="v" direction="in"/>
        </method>
        <method name="GetTechnologies">
            <arg name="technologies" type="a(oa{sv})" direction="out"/>
        </method>
        <method name="RemoveProvider">
            <arg name="provider" type="o" direction="in"/>
            <annotation
                name="org.freedesktop.DBus.Deprecated"
                value="true"
            />
        </method>
        <method name="GetServices">
            <arg name="services" type="a(oa{sv})" direction="out"/>
        </method>
        <method name="GetPeers">
            <arg name="peers" type="a(oa{sv})" direction="out"/>
        </method>
        <method name="ConnectProvider">
            <arg name="provider" type="a{sv}" direction="in"/>
            <arg name="path" type="o" direction="out"/>
            <annotation
                name="org.freedesktop.DBus.Deprecated"
                value="true"
            />
        </method>
        <method name="RegisterAgent">
            <arg name="path" type="o" direction="in"/>
        </method>
        <method name="UnregisterAgent">
            <arg name="path" type="o" direction="in"/>
        </method>
        <method name="RegisterCounter">
            <arg name="path" type="o" direction="in"/>
            <arg name="accuracy" type="u" direction="in"/>
            <arg name="period" type="u" direction="in"/>
        </method>
        <method name="UnregisterCounter">
            <arg name="path" type="o" direction="in"/>
        </method>
        <method name="CreateSession">
            <arg name="settings" type="a{sv}" direction="in"/>
            <arg name="notifier" type="o" direction="in"/>
            <arg name="session" type="o" direction="out"/>
        </method>
        <method name="DestroySession">
            <arg name="session" type="o" direction="in"/>
        </method>
        <method name="RequestPrivateNetwork">
            <arg name="path" type="o" direction="out"/>
            <arg name="settings" type="a{sv}" direction="out"/>
            <arg name="socket" type="h" direction="out"/>
        </method>
        <method name="ReleasePrivateNetwork">
            <arg name="path" type="o" direction="in"/>
        </method>
        <method name="RegisterPeerService">
            <arg name="specification" type="a{sv}" direction="in"/>
            <arg name="master" type="b" direction="in"/>
        </method>
        <method name="UnregisterPeerService">
            <arg name="specification" type="a{sv}" direction="in"/>
        </method>
        <signal name="PropertyChanged">
            <arg name="name" type="s"/>
            <arg name="value" type="v"/>
        </signal>
        <signal name="TechnologyAdded">
            <arg name="path" type="o"/>
            <arg name="properties" type="a{sv}"/>
        </signal>
        <signal name="TechnologyRemoved">
            <arg name="path" type="o"/>
        </signal>
        <signal name="ServicesChanged">
            <arg name="changed" type="a(oa{sv})"/>
            <arg name="removed" type="ao"/>
        </signal>
        <signal name="PeersChanged">
            <arg name="changed" type="a(oa{sv})"/>
            <arg name="removed" type="ao"/>
        </signal>
    </interface>
    <interface name="net.connman.Clock">
        <method name="GetProperties">
            <arg name="properties" type="a{sv}" direction="out"/>
        </method>
        <method name="SetProperty">
            <arg name="name" type="s" direction="in"/>
            <arg name="value" type="v" direction="in"/>
        </method>
        <signal name="PropertyChanged">
            <arg name="name" type="s"/>
            <arg name="value" type="v"/>
        </signal>
    </interface>
    <node name="net">
        <node name="connman">
            <node name="iwd_agent">
                <interface name="org.freedesktop.DBus.Introspectable"/>
                <interface name="net.connman.iwd.Agent">
                    <method name="Release"/>
                    <method name="RequestPassphrase">
                        <arg name="path" type="o" direction="in"/>
                        <arg name="passphrase" type="s" direction="out"/>
                    </method>
                    <method name="Cancel">
                        <arg name="reason" type="s" direction="in"/>
                    </method>
                </interface>
            </node>
            <node name="service">
                <node name="ethernet_02693694c027_cable">
                    <interface
                        name="org.freedesktop.DBus.Introspectable"
                    />
                    <interface name="net.connman.Service">
                        <method name="GetProperties">
                            <arg
                                name="properties"
                                type="a{sv}"
                                direction="out"
                            />
                            <annotation
                                name="org.freedesktop.DBus.Deprecated"
                                value="true"
                            />
                        </method>
                        <method name="SetProperty">
                            <arg name="name" type="s" direction="in"/>
                            <arg name="value" type="v" direction="in"/>
                        </method>
                        <method name="ClearProperty">
                            <arg name="name" type="s" direction="in"/>
                        </method>
                        <method name="Connect"/>
                        <method name="Disconnect"/>
                        <method name="Remove"/>
                        <method name="MoveBefore">
                            <arg name="service" type="o" direction="in"/>
                        </method>
                        <method name="MoveAfter">
                            <arg name="service" type="o" direction="in"/>
                        </method>
                        <method name="ResetCounters"/>
                        <signal name="PropertyChanged">
                            <arg name="name" type="s"/>
                            <arg name="value" type="v"/>
                        </signal>
                    </interface>
                </node>
                <node name="ethernet_366cdd276940_cable">
                    <interface
                        name="org.freedesktop.DBus.Introspectable"
                    />
                    <interface name="net.connman.Service"/>
                </node>
                <node name="ethernet_723575276940_cable">
                    <interface
                        name="org.freedesktop.DBus.Introspectable"
                    />
                    <interface name="net.connman.Service"/>
                </node>
                <node name="ethernet_ae8d48867953_cable">
                    <interface
                        name="org.freedesktop.DBus.Introspectable"
                    />
                    <interface name="net.connman.Service"/>
                </node>
                <node name="ethernet_ba6926867953_cable">
                    <interface
                        name="org.freedesktop.DBus.Introspectable"
                    />
                    <interface name="net.connman.Service"/>
                </node>
                <node
                    name="wifi_001500d77076_4e4554474541525f31314143_managed_psk"
                >
                    <interface
                        name="org.freedesktop.DBus.Introspectable"
                    />
                    <interface name="net.connman.Service"/>
                </node>
            </node>
            <node name="technology">
                <node name="bluetooth">
                    <interface
                        name="org.freedesktop.DBus.Introspectable"
                    />
                    <interface name="net.connman.Technology">
                        <method name="GetProperties">
                            <arg
                                name="properties"
                                type="a{sv}"
                                direction="out"
                            />
                            <annotation
                                name="org.freedesktop.DBus.Deprecated"
                                value="true"
                            />
                        </method>
                        <method name="SetProperty">
                            <arg name="name" type="s" direction="in"/>
                            <arg name="value" type="v" direction="in"/>
                        </method>
                        <method name="Scan"/>
                        <signal name="PropertyChanged">
                            <arg name="name" type="s"/>
                            <arg name="value" type="v"/>
                        </signal>
                    </interface>
                </node>
                <node name="ethernet">
                    <interface
                        name="org.freedesktop.DBus.Introspectable"
                    />
                    <interface name="net.connman.Technology"/>
                </node>
                <node name="wifi">
                    <interface
                        name="org.freedesktop.DBus.Introspectable"
                    />
                    <interface name="net.connman.Technology"/>
                </node>
            </node>
        </node>
    </node>
</node>

I changed the relevant part in (your guess about the missing path seems correct to me):

            print('-----------------------------------')
            t = p[1]
            print(f'-- {t["Name"][1]}: {p[0]} --')
            if use_dbussy:
                i = bus['net.connman']['/net/connman/technology/wifi'].get_interface('net.connman.Technology')
                await i.Scan()
            elif use_ravel:
                s = await bus.get_proxy_interface_async(bus_name,  p[0], 'net.connman.Technology')
                i = s(connection=bus.connection, dest='net.connman.Technology')['/net/connman/technology/wifi']
                await i.Scan()
            else:  # use old
                import dbus
                i = dbus.Interface(dbus.SystemBus().get_object("net.connman",
                                                               "/net/connman/technology/wifi"),
                                   "net.connman.Technology")
                i.Scan()
            await asyncio.sleep(10)

and dbussy and "old" seem to work, while ravel bombs with:

-- WiFi: /net/connman/technology/wifi --
Traceback (most recent call last):
  File "/home/mcon/projects/dbussy/networks.py", line 55, in main
    await i.Scan()
TypeError: 'NoneType' object is not subscriptable

Any further hint?
TiA!

[ldo]

That’s a mysterious message to get at that point. Perhaps try dumping out some more info about the “i” object before that Scan() call?