class DBus::ProxyObject

D-Bus proxy object class

Class representing a remote object in an external application. Typically, calling a method on an instance of a ProxyObject sends a message over the bus so that the method is executed remotely on the correctponding object.

Attributes

api[R]

@api private @return [ApiOptions]

bus[R]

The bus the object is reachable via.

default_iface[RW]

@return [String] The name of the default interface of the object.

destination[R]

The (remote) destination of the object.

introspected[RW]

Flag determining whether the object has been introspected.

path[R]

The path to the object.

subnodes[RW]

The names of direct subnodes of the object in the tree.

Public Class Methods

new(bus, dest, path, api: ApiOptions::CURRENT) click to toggle source

Creates a new proxy object living on the given bus at destination dest on the given path.

   # File lib/dbus/proxy_object.rb
36 def initialize(bus, dest, path, api: ApiOptions::CURRENT)
37   @bus = bus
38   @destination = dest
39   @path = ObjectPath.new(path)
40   @introspected = false
41   @interfaces = {}
42   @subnodes = []
43   @api = api
44 end

Public Instance Methods

[](intfname) click to toggle source

Retrieves an interface of the proxy object @param [String] intfname @return [ProxyObjectInterface]

   # File lib/dbus/proxy_object.rb
55 def [](intfname)
56   introspect unless introspected
57   ifc = @interfaces[intfname]
58   raise DBus::Error, "no such interface `#{intfname}' on object `#{@path}'" unless ifc
59   ifc
60 end
[]=(intfname, intf) click to toggle source

Maps the given interface name intfname to the given interface _intf. @param [String] intfname @param [ProxyObjectInterface] intf @return [ProxyObjectInterface] @api private

   # File lib/dbus/proxy_object.rb
67 def []=(intfname, intf)
68   @interfaces[intfname] = intf
69 end
define_shortcut_methods() click to toggle source

For each non duplicated method name in any interface present on the caller, defines a shortcut method dynamically. This function is automatically called when a {ProxyObject} is introspected.

    # File lib/dbus/proxy_object.rb
 85 def define_shortcut_methods
 86   # builds a list of duplicated methods
 87   dup_meths = []
 88   univocal_meths = {}
 89   @interfaces.each_value do |intf|
 90     intf.methods.each_value do |meth|
 91       name = meth.name.to_sym
 92       # don't overwrite instance methods!
 93       next if dup_meths.include?(name)
 94       next if self.class.instance_methods.include?(name)
 95       if univocal_meths.include? name
 96         univocal_meths.delete name
 97         dup_meths << name
 98       else
 99         univocal_meths[name] = intf
100       end
101     end
102   end
103   univocal_meths.each do |name, intf|
104     # creates a shortcut function that forwards each call to the method on
105     # the appropriate intf
106     singleton_class.class_eval do
107       redefine_method name do |*args, &reply_handler|
108         intf.method(name).call(*args, &reply_handler)
109       end
110     end
111   end
112 end
has_iface?(name) click to toggle source

Returns whether the object has an interface with the given name.

    # File lib/dbus/proxy_object.rb
115 def has_iface?(name)
116   introspect unless introspected
117   @interfaces.key?(name)
118 end
interfaces() click to toggle source

Returns the interfaces of the object.

   # File lib/dbus/proxy_object.rb
47 def interfaces
48   introspect unless introspected
49   @interfaces.keys
50 end
introspect() click to toggle source

Introspects the remote object. Allows you to find and select interfaces on the object.

   # File lib/dbus/proxy_object.rb
73 def introspect
74   # Synchronous call here.
75   xml = @bus.introspect_data(@destination, @path)
76   ProxyObjectFactory.introspect_into(self, xml)
77   define_shortcut_methods
78   xml
79 end
on_signal(name, &block) click to toggle source

Registers a handler, the code block, for a signal with the given name. It uses default_iface which must have been set. @return [void]

    # File lib/dbus/proxy_object.rb
123 def on_signal(name, &block)
124   # TODO: improve
125   raise NoMethodError unless @default_iface && has_iface?(@default_iface)
126   @interfaces[@default_iface].on_signal(name, &block)
127 end

Private Instance Methods

method_missing(name, *args, &reply_handler) click to toggle source

Handles all unkown methods, mostly to route method calls to the default interface.

    # File lib/dbus/proxy_object.rb
134 def method_missing(name, *args, &reply_handler)
135   unless @default_iface && has_iface?(@default_iface)
136     # TODO: distinguish:
137     # - di not specified
138     # TODO
139     # - di is specified but not found in introspection data
140     raise NoMethodError, "undefined method `#{name}' for DBus interface `#{@default_iface}' on object `#{@path}'"
141   end
142 
143   begin
144     @interfaces[@default_iface].method(name).call(*args, &reply_handler)
145   rescue NameError => e
146     # interesting, foo.method("unknown")
147     # raises NameError, not NoMethodError
148     raise unless e.to_s =~ /undefined method `#{name}'/
149     # BTW e.exception("...") would preserve the class.
150     raise NoMethodError, "undefined method `#{name}' for DBus interface `#{@default_iface}' on object `#{@path}'"
151   end
152 end