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Problem with reading Properties #41

swistaczek opened this Issue · 3 comments

2 participants


First of all I would like to say thanks you for great library :), I am trying to read properties for NetworkManager ( ) using following code:

    @bus        = DBus::SystemBus.instance
    @mm_service = @bus['org.freedesktop.ModemManager'
    @proxy = @mm_service.object('/org/freedesktop/ModemManager/Modems/0')
[85] pry(main)> @proxy['org.freedesktop.ModemManager.Modem']['Enabled']
NoMethodError: undefined method `Get' for #<DBus::ProxyObjectInterface:0x0000000304d190>
from /home/ubuntu/.rvm/gems/ruby-1.9.3-p392/bundler/gems/ruby-dbus-f25a6953df05/lib/dbus/introspect.rb:333:in `[]'

Could you @mvidner please point me where I am making mistake? Thanks in advantage.

I would like to fix this odd method


Thanks for the report. It turns out that ModemManager introspection output is a bit quirky, splitting the Properties interface into two elements (see below) and ruby-dbus only interprets one of them, missing the Properties.Get method.

$ dbus-send --system --print-reply --dest=org.freedesktop.ModemManager /org/freedesktop/ModemManager/Modems/0 org.freedesktop.DBus.Introspectable.Introspect | grep \<interface
  <interface name="org.freedesktop.DBus.Introspectable">
  <interface name="org.freedesktop.DBus.Properties">                              HERE
  <interface name="org.freedesktop.ModemManager.Modem.Simple">
  <interface name="org.freedesktop.ModemManager.Modem.Gsm.Ussd">
  <interface name="org.freedesktop.ModemManager.Modem.Location">
  <interface name="org.freedesktop.ModemManager.Modem.Gsm.SMS">
  <interface name="org.freedesktop.ModemManager.Modem.Gsm.Network">
  <interface name="org.freedesktop.ModemManager.Modem.Gsm.Card">
  <interface name="org.freedesktop.ModemManager.Modem.Time">
  <interface name="org.freedesktop.DBus.Properties">                             AND HERE
  <interface name="org.freedesktop.ModemManager.Modem">

I think I should make the introspection parser merge them, perhaps even with a set of fall back property introspection.


Hello @mvidner, I was unable to find section responsible for params merge. Could you help me with fixing this bug please?

@mvidner mvidner added a commit that closed this issue
@mvidner reading split interface elements in introspection; fixes #41
ModemManager does this with the property interface, resulting in
    NoMethodError: undefined method `Get' for #<DBus::ProxyObjectInterface:...>
without the fix
@mvidner mvidner closed this in f54a324
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