Class: Gio::DBusConnection

Inherits:
Object
  • Object
show all
Defined in:
(unknown)

Overview

The GDBus::Connection type is used for D-Bus connections to remote peers such as a message buses. It is a low-level API that offers a lot of flexibility. For instance, it lets you establish a connection over any transport that can by represented as a #GIOStream.

This class is rarely used directly in D-Bus clients. If you are writing a D-Bus client, it is often easier to use the g_bus_own_name(), g_bus_watch_name() or g_dbus_proxy_new_for_bus() APIs.

As an exception to the usual GLib rule that a particular object must not be used by two threads at the same time, GDBus::Connection’s methods may be called from any thread. This is so that g_bus_get() and g_bus_get_sync() can safely return the same GDBus::Connection when called from any thread.

Most of the ways to obtain a GDBus::Connection automatically initialize it (i.e. connect to D-Bus): for instance, g_dbus_connection_new() and g_bus_get(), and the synchronous versions of those methods, give you an initialized connection. Language bindings for GIO should use g_initable_new() or g_async_initable_new_async(), which also initialize the connection.

If you construct an uninitialized GDBus::Connection, such as via g_object_new(), you must initialize it via g_initable_init() or g_async_initable_init_async() before using its methods or properties. Calling methods or accessing properties on a GDBus::Connection that has not completed initialization successfully is considered to be invalid, and leads to undefined behaviour. In particular, if initialization fails with a #GError, the only valid thing you can do with that GDBus::Connection is to free it with g_object_unref().

## An example D-Bus server # #gdbus-server

Here is an example for a D-Bus server: [gdbus-example-server.c](git.gnome.org/browse/glib/tree/gio/tests/gdbus-example-server.c)

## An example for exporting a subtree # #gdbus-subtree-server

Here is an example for exporting a subtree: [gdbus-example-subtree.c](git.gnome.org/browse/glib/tree/gio/tests/gdbus-example-subtree.c)

## An example for file descriptor passing # #gdbus-unix-fd-client

Here is an example for passing UNIX file descriptors: [gdbus-unix-fd-client.c](git.gnome.org/browse/glib/tree/gio/tests/gdbus-example-unix-fd-client.c)

## An example for exporting a GObject # #gdbus-export

Here is an example for exporting a #GObject: [gdbus-example-export.c](git.gnome.org/browse/glib/tree/gio/tests/gdbus-example-export.c)

Instance Method Summary collapse

Instance Method Details

#add_filter(filter_function, user_data, user_data_free_func) ⇒ Integer

Adds a message filter. Filters are handlers that are run on all incoming and outgoing messages, prior to standard dispatch. Filters are run in the order that they were added. The same handler can be added as a filter more than once, in which case it will be run more than once. Filters added during a filter callback won’t be run on the message being processed. Filter functions are allowed to modify and even drop messages.

Note that filters are run in a dedicated message handling thread so they can’t block and, generally, can’t do anything but signal a worker thread. Also note that filters are rarely needed - use API such as g_dbus_connection_send_message_with_reply(), g_dbus_connection_signal_subscribe() or g_dbus_connection_call() instead.

If a filter consumes an incoming message the message is not dispatched anywhere else - not even the standard dispatch machinery (that API such as g_dbus_connection_signal_subscribe() and g_dbus_connection_send_message_with_reply() relies on) will see the message. Similarly, if a filter consumes an outgoing message, the message will not be sent to the other peer.

If user_data_free_func is non-nil, it will be called (in the thread-default main context of the thread you are calling this method from) at some point after user_data is no longer needed. (It is not guaranteed to be called synchronously when the filter is removed, and may be called after connection has been destroyed.)

Parameters:

  • filter_function (Gio::DBusMessageFilterFunction) —

    a filter function

  • user_data (GObject) —

    user data to pass to filter_function

  • user_data_free_func (GLib::DestroyNotify) —

    function to free user_data with when filter is removed or nil

Returns:

  • (Integer) —

    a filter identifier that can be used with g_dbus_connection_remove_filter()

#address=(address) ⇒ String

A D-Bus address specifying potential endpoints that can be used when establishing the connection.

Parameters:

  • address (String)

Returns:

  • (String) —

    address

#authentication_observer=(authentication_observer) ⇒ Gio::DBusAuthObserver

A GDBus::AuthObserver object to assist in the authentication process or nil.

Parameters:

Returns:

#call(bus_name, object_path, interface_name, method_name, parameters, reply_type, flags, timeout_msec, cancellable, callback, user_data) ⇒ nil

Asynchronously invokes the method_name method on the interface_name D-Bus interface on the remote object at object_path owned by bus_name.

If connection is closed then the operation will fail with %G_IO_ERROR_CLOSED. If cancellable is canceled, the operation will fail with %G_IO_ERROR_CANCELLED. If parameters contains a value not compatible with the D-Bus protocol, the operation fails with %G_IO_ERROR_INVALID_ARGUMENT.

If reply_type is non-nil then the reply will be checked for having this type and an error will be raised if it does not match. Said another way, if you give a reply_type then any non-nil return value will be of this type. Unless it’s %G_VARIANT_TYPE_UNIT, the reply_type will be a tuple containing one or more values.

If the parameters #GVariant is floating, it is consumed. This allows convenient ‘inline’ use of g_variant_new(), e.g.:

g_dbus_connection_call (connection,
                        "org.freedesktop.StringThings",
                        "/org/freedesktop/StringThings",
                        "org.freedesktop.StringThings",
                        "TwoStrings",
                        g_variant_new ("(ss)",
                                       "Thing One",
                                       "Thing Two"),
                        NULL,
                        G_DBUS_CALL_FLAGS_NONE,
                        -1,
                        NULL,
                        (GAsyncReadyCallback) two_strings_done,
                        NULL);

This is an asynchronous method. When the operation is finished, callback will be invoked in the

thread-default main context][g-main-context-push-thread-default

of the thread you are calling this method from. You can then call g_dbus_connection_call_finish() to get the result of the operation. See g_dbus_connection_call_sync() for the synchronous version of this function.

If callback is nil then the D-Bus method call message will be sent with the %G_DBUS_MESSAGE_FLAGS_NO_REPLY_EXPECTED flag set.

Parameters:

  • bus_name (String) —

    a unique or well-known bus name or nil if connection is not a message bus connection

  • object_path (String) —

    path of remote object

  • interface_name (String) —

    D-Bus interface to invoke method on

  • method_name (String) —

    the name of the method to invoke

  • parameters (GLib::Variant) —

    a #GVariant tuple with parameters for the method or nil if not passing parameters

  • reply_type (GLib::VariantType) —

    the expected type of the reply (which will be a tuple), or nil

  • flags (Gio::DBusCallFlags) —

    flags from the GDBus::CallFlags enumeration

  • timeout_msec (Integer) —

    the timeout in milliseconds, -1 to use the default timeout or %G_MAXINT for no timeout

  • cancellable (Gio::Cancellable) —

    a #GCancellable or nil

  • callback (Gio::AsyncReadyCallback) —

    a GAsync::ReadyCallback to call when the request is satisfied or nil if you don’t care about the result of the method invocation

  • user_data (GObject) —

    the data to pass to callback

Returns:

  • (nil)

#call_finish(res) ⇒ GLib::Variant

Finishes an operation started with g_dbus_connection_call().

Parameters:

  • res (Gio::AsyncResult) —

    a GAsync::Result obtained from the #GAsyncReadyCallback passed to g_dbus_connection_call()

Returns:

  • (GLib::Variant) —

    nil if error is set. Otherwise a #GVariant tuple with return values. Free with g_variant_unref().

#call_sync(bus_name, object_path, interface_name, method_name, parameters, reply_type, flags, timeout_msec, cancellable) ⇒ GLib::Variant

Synchronously invokes the method_name method on the interface_name D-Bus interface on the remote object at object_path owned by bus_name.

If connection is closed then the operation will fail with %G_IO_ERROR_CLOSED. If cancellable is canceled, the operation will fail with %G_IO_ERROR_CANCELLED. If parameters contains a value not compatible with the D-Bus protocol, the operation fails with %G_IO_ERROR_INVALID_ARGUMENT.

If reply_type is non-nil then the reply will be checked for having this type and an error will be raised if it does not match. Said another way, if you give a reply_type then any non-nil return value will be of this type.

If the parameters #GVariant is floating, it is consumed. This allows convenient ‘inline’ use of g_variant_new(), e.g.:

g_dbus_connection_call_sync (connection,
                             "org.freedesktop.StringThings",
                             "/org/freedesktop/StringThings",
                             "org.freedesktop.StringThings",
                             "TwoStrings",
                             g_variant_new ("(ss)",
                                            "Thing One",
                                            "Thing Two"),
                             NULL,
                             G_DBUS_CALL_FLAGS_NONE,
                             -1,
                             NULL,
                             &error);

The calling thread is blocked until a reply is received. See g_dbus_connection_call() for the asynchronous version of this method.

Parameters:

  • bus_name (String) —

    a unique or well-known bus name or nil if connection is not a message bus connection

  • object_path (String) —

    path of remote object

  • interface_name (String) —

    D-Bus interface to invoke method on

  • method_name (String) —

    the name of the method to invoke

  • parameters (GLib::Variant) —

    a #GVariant tuple with parameters for the method or nil if not passing parameters

  • reply_type (GLib::VariantType) —

    the expected type of the reply, or nil

  • flags (Gio::DBusCallFlags) —

    flags from the GDBus::CallFlags enumeration

  • timeout_msec (Integer) —

    the timeout in milliseconds, -1 to use the default timeout or %G_MAXINT for no timeout

  • cancellable (Gio::Cancellable) —

    a #GCancellable or nil

Returns:

  • (GLib::Variant) —

    nil if error is set. Otherwise a #GVariant tuple with return values. Free with g_variant_unref().

#call_with_unix_fd_list(bus_name, object_path, interface_name, method_name, parameters, reply_type, flags, timeout_msec, fd_list, cancellable, callback, user_data) ⇒ nil

Like g_dbus_connection_call() but also takes a GUnix::FDList object.

This method is only available on UNIX.

Parameters:

  • bus_name (String) —

    a unique or well-known bus name or nil if connection is not a message bus connection

  • object_path (String) —

    path of remote object

  • interface_name (String) —

    D-Bus interface to invoke method on

  • method_name (String) —

    the name of the method to invoke

  • parameters (GLib::Variant) —

    a #GVariant tuple with parameters for the method or nil if not passing parameters

  • reply_type (GLib::VariantType) —

    the expected type of the reply, or nil

  • flags (Gio::DBusCallFlags) —

    flags from the GDBus::CallFlags enumeration

  • timeout_msec (Integer) —

    the timeout in milliseconds, -1 to use the default timeout or %G_MAXINT for no timeout

  • fd_list (Gio::UnixFDList) —

    a GUnix::FDList or nil

  • cancellable (Gio::Cancellable) —

    a #GCancellable or nil

  • callback (Gio::AsyncReadyCallback) —

    a GAsync::ReadyCallback to call when the request is satisfied or nil if you don’t * care about the result of the method invocation

  • user_data (GObject) —

    The data to pass to callback.

Returns:

  • (nil)

#call_with_unix_fd_list_finish(out_fd_list, res) ⇒ GLib::Variant

Finishes an operation started with g_dbus_connection_call_with_unix_fd_list().

Parameters:

  • out_fd_list (Gio::UnixFDList) —

    return location for a GUnix::FDList or nil

  • res (Gio::AsyncResult) —

    a GAsync::Result obtained from the #GAsyncReadyCallback passed to g_dbus_connection_call_with_unix_fd_list()

Returns:

  • (GLib::Variant) —

    nil if error is set. Otherwise a #GVariant tuple with return values. Free with g_variant_unref().

#call_with_unix_fd_list_sync(bus_name, object_path, interface_name, method_name, parameters, reply_type, flags, timeout_msec, fd_list, out_fd_list, cancellable) ⇒ GLib::Variant

Like g_dbus_connection_call_sync() but also takes and returns GUnix::FDList objects.

This method is only available on UNIX.

Parameters:

  • bus_name (String) —

    a unique or well-known bus name or nil if connection is not a message bus connection

  • object_path (String) —

    path of remote object

  • interface_name (String) —

    D-Bus interface to invoke method on

  • method_name (String) —

    the name of the method to invoke

  • parameters (GLib::Variant) —

    a #GVariant tuple with parameters for the method or nil if not passing parameters

  • reply_type (GLib::VariantType) —

    the expected type of the reply, or nil

  • flags (Gio::DBusCallFlags) —

    flags from the GDBus::CallFlags enumeration

  • timeout_msec (Integer) —

    the timeout in milliseconds, -1 to use the default timeout or %G_MAXINT for no timeout

  • fd_list (Gio::UnixFDList) —

    a GUnix::FDList or nil

  • out_fd_list (Gio::UnixFDList) —

    return location for a GUnix::FDList or nil

  • cancellable (Gio::Cancellable) —

    a #GCancellable or nil

Returns:

  • (GLib::Variant) —

    nil if error is set. Otherwise a #GVariant tuple with return values. Free with g_variant_unref().

#capabilities ⇒ Gio::DBusCapabilityFlags

Flags from the GDBus::CapabilityFlags enumeration representing connection features negotiated with the other peer.

Returns:

#capabilities=(capabilities) ⇒ Gio::DBusCapabilityFlags

Flags from the GDBus::CapabilityFlags enumeration representing connection features negotiated with the other peer.

Parameters:

Returns:

#close(cancellable, callback, user_data) ⇒ nil

Closes connection. Note that this never causes the process to exit (this might only happen if the other end of a shared message bus connection disconnects, see GDBus::Connection:exit-on-close).

Once the connection is closed, operations such as sending a message will return with the error %G_IO_ERROR_CLOSED. Closing a connection will not automatically flush the connection so queued messages may be lost. Use g_dbus_connection_flush() if you need such guarantees.

If connection is already closed, this method fails with %G_IO_ERROR_CLOSED.

When connection has been closed, the GDBus::Connection::closed signal is emitted in the

thread-default main context][g-main-context-push-thread-default

of the thread that connection was constructed in.

This is an asynchronous method. When the operation is finished, callback will be invoked in the

thread-default main context][g-main-context-push-thread-default

of the thread you are calling this method from. You can then call g_dbus_connection_close_finish() to get the result of the operation. See g_dbus_connection_close_sync() for the synchronous version.

Parameters:

  • cancellable (Gio::Cancellable) —

    a #GCancellable or nil

  • callback (Gio::AsyncReadyCallback) —

    a GAsync::ReadyCallback to call when the request is satisfied or nil if you don’t care about the result

  • user_data (GObject) —

    The data to pass to callback

Returns:

  • (nil)

#close_finish(res) ⇒ TrueClass

Finishes an operation started with g_dbus_connection_close().

Parameters:

  • res (Gio::AsyncResult) —

    a GAsync::Result obtained from the #GAsyncReadyCallback passed to g_dbus_connection_close()

Returns:

  • (TrueClass) —

    true if the operation succeeded, false if error is set

#close_sync(cancellable) ⇒ TrueClass

Synchronously closes connection. The calling thread is blocked until this is done. See g_dbus_connection_close() for the asynchronous version of this method and more details about what it does.

Parameters:

Returns:

  • (TrueClass) —

    true if the operation succeeded, false if error is set

#closed=(closed) ⇒ TrueClass

A boolean specifying whether the connection has been closed.

Parameters:

  • closed (TrueClass)

Returns:

  • (TrueClass) —

    closed

  • (TrueClass) —

    closed

#closed? ⇒ TrueClass

A boolean specifying whether the connection has been closed.

Returns:

  • (TrueClass) —

    closed

#emit_signal(destination_bus_name, object_path, interface_name, signal_name, parameters) ⇒ TrueClass

Emits a signal.

If the parameters GVariant is floating, it is consumed.

This can only fail if parameters is not compatible with the D-Bus protocol (%G_IO_ERROR_INVALID_ARGUMENT), or if connection has been closed (%G_IO_ERROR_CLOSED).

Parameters:

  • destination_bus_name (String) —

    the unique bus name for the destination for the signal or nil to emit to all listeners

  • object_path (String) —

    path of remote object

  • interface_name (String) —

    D-Bus interface to emit a signal on

  • signal_name (String) —

    the name of the signal to emit

  • parameters (GLib::Variant) —

    a #GVariant tuple with parameters for the signal or nil if not passing parameters

Returns:

  • (TrueClass) —

    true unless error is set

#exit_on_close ⇒ TrueClass

Gets whether the process is terminated when connection is closed by the remote peer. See GDBus::Connection:exit-on-close for more details.

Returns:

  • (TrueClass) —

    whether the process is terminated when connection is closed by the remote peer

#exit_on_close=(exit_on_close) ⇒ TrueClass

A boolean specifying whether the process will be terminated (by calling ‘raise(SIGTERM)`) if the connection is closed by the remote peer.

Note that GDBus::Connection objects returned by g_bus_get_finish() and g_bus_get_sync() will (usually) have this property set to true.

Parameters:

  • exit_on_close (TrueClass)

Returns:

  • (TrueClass) —

    exit-on-close

  • (TrueClass) —

    exit-on-close

#exit_on_close? ⇒ TrueClass

A boolean specifying whether the process will be terminated (by calling ‘raise(SIGTERM)`) if the connection is closed by the remote peer.

Note that GDBus::Connection objects returned by g_bus_get_finish() and g_bus_get_sync() will (usually) have this property set to true.

Returns:

  • (TrueClass) —

    exit-on-close

#export_action_group(object_path, action_group) ⇒ Integer

Exports action_group on connection at object_path.

The implemented D-Bus API should be considered private. It is subject to change in the future.

A given object path can only have one action group exported on it. If this constraint is violated, the export will fail and 0 will be returned (with error set accordingly).

You can unexport the action group using g_dbus_connection_unexport_action_group() with the return value of this function.

The thread default main context is taken at the time of this call. All incoming action activations and state change requests are reported from this context. Any changes on the action group that cause it to emit signals must also come from this same context. Since incoming action activations and state change requests are rather likely to cause changes on the action group, this effectively limits a given action group to being exported from only one main context.

Parameters:

  • object_path (String) —

    a D-Bus object path

  • action_group (Gio::ActionGroup) —

    a GAction::Group

Returns:

  • (Integer) —

    the ID of the export (never zero), or 0 in case of failure

#export_menu_model(object_path, menu) ⇒ Integer

Exports menu on connection at object_path.

The implemented D-Bus API should be considered private. It is subject to change in the future.

An object path can only have one menu model exported on it. If this constraint is violated, the export will fail and 0 will be returned (with error set accordingly).

You can unexport the menu model using g_dbus_connection_unexport_menu_model() with the return value of this function.

Parameters:

  • object_path (String) —

    a D-Bus object path

  • menu (Gio::MenuModel) —

    a GMenu::Model

Returns:

  • (Integer) —

    the ID of the export (never zero), or 0 in case of failure

#flags ⇒ Gio::DBusConnectionFlags

Flags from the GDBus::ConnectionFlags enumeration.

Returns:

#flags=(flags) ⇒ Gio::DBusConnectionFlags

Flags from the GDBus::ConnectionFlags enumeration.

Parameters:

Returns:

#flush(cancellable, callback, user_data) ⇒ nil

Asynchronously flushes connection, that is, writes all queued outgoing message to the transport and then flushes the transport (using g_output_stream_flush_async()). This is useful in programs that wants to emit a D-Bus signal and then exit immediately. Without flushing the connection, there is no guaranteed that the message has been sent to the networking buffers in the OS kernel.

This is an asynchronous method. When the operation is finished, callback will be invoked in the

thread-default main context][g-main-context-push-thread-default

of the thread you are calling this method from. You can then call g_dbus_connection_flush_finish() to get the result of the operation. See g_dbus_connection_flush_sync() for the synchronous version.

Parameters:

  • cancellable (Gio::Cancellable) —

    a #GCancellable or nil

  • callback (Gio::AsyncReadyCallback) —

    a GAsync::ReadyCallback to call when the request is satisfied or nil if you don’t care about the result

  • user_data (GObject) —

    The data to pass to callback

Returns:

  • (nil)

#flush_finish(res) ⇒ TrueClass

Finishes an operation started with g_dbus_connection_flush().

Parameters:

  • res (Gio::AsyncResult) —

    a GAsync::Result obtained from the #GAsyncReadyCallback passed to g_dbus_connection_flush()

Returns:

  • (TrueClass) —

    true if the operation succeeded, false if error is set

#flush_sync(cancellable) ⇒ TrueClass

Synchronously flushes connection. The calling thread is blocked until this is done. See g_dbus_connection_flush() for the asynchronous version of this method and more details about what it does.

Parameters:

Returns:

  • (TrueClass) —

    true if the operation succeeded, false if error is set

#guid ⇒ String

The GUID of the peer performing the role of server when authenticating.

If you are constructing a GDBus::Connection and pass %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER in the GDBus::Connection:flags property then you MUST also set this property to a valid guid.

If you are constructing a GDBus::Connection and pass %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT in the GDBus::Connection:flags property you will be able to read the GUID of the other peer here after the connection has been successfully initialized.

Returns:

  • (String) —

    guid

#guid=(guid) ⇒ String

The GUID of the peer performing the role of server when authenticating.

If you are constructing a GDBus::Connection and pass %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER in the GDBus::Connection:flags property then you MUST also set this property to a valid guid.

If you are constructing a GDBus::Connection and pass %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT in the GDBus::Connection:flags property you will be able to read the GUID of the other peer here after the connection has been successfully initialized.

Parameters:

  • guid (String)

Returns:

  • (String) —

    guid

  • (String) —

    guid

#is_closed ⇒ TrueClass

Gets whether connection is closed.

Returns:

  • (TrueClass) —

    true if the connection is closed, false otherwise

#last_serial ⇒ Integer

Retrieves the last serial number assigned to a GDBus::Message on the current thread. This includes messages sent via both low-level API such as g_dbus_connection_send_message() as well as high-level API such as g_dbus_connection_emit_signal(), g_dbus_connection_call() or g_dbus_proxy_call().

Returns:

  • (Integer) —

    the last used serial or zero when no message has been sent within the current thread

#new_finish(res) ⇒ Gio::DBusConnection

Finishes an operation started with g_dbus_connection_new().

Parameters:

  • res (Gio::AsyncResult) —

    a GAsync::Result obtained from the #GAsyncReadyCallback passed to g_dbus_connection_new().

Returns:

  • (Gio::DBusConnection) —

    a GDBus::Connection or nil if error is set. Free with g_object_unref().

#new_for_address_finish(res) ⇒ Gio::DBusConnection

Finishes an operation started with g_dbus_connection_new_for_address().

Parameters:

  • res (Gio::AsyncResult) —

    a GAsync::Result obtained from the #GAsyncReadyCallback passed to g_dbus_connection_new()

Returns:

  • (Gio::DBusConnection) —

    a GDBus::Connection or nil if error is set. Free with g_object_unref().

#new_for_address_sync(address, flags, observer, cancellable) ⇒ Gio::DBusConnection

Synchronously connects and sets up a D-Bus client connection for exchanging D-Bus messages with an endpoint specified by address which must be in the [D-Bus address format](dbus.freedesktop.org/doc/dbus-specification.html#addresses).

This constructor can only be used to initiate client-side connections - use g_dbus_connection_new_sync() if you need to act as the server. In particular, flags cannot contain the %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER or %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_ALLOW_ANONYMOUS flags.

This is a synchronous failable constructor. See g_dbus_connection_new_for_address() for the asynchronous version.

If observer is not nil it may be used to control the authentication process.

Parameters:

Returns:

  • (Gio::DBusConnection) —

    a GDBus::Connection or nil if error is set. Free with g_object_unref().

#new_sync(stream, guid, flags, observer, cancellable) ⇒ Gio::DBusConnection

Synchronously sets up a D-Bus connection for exchanging D-Bus messages with the end represented by stream.

If stream is a GSocket::Connection, then the corresponding #GSocket will be put into non-blocking mode.

The D-Bus connection will interact with stream from a worker thread. As a result, the caller should not interact with stream after this method has been called, except by calling g_object_unref() on it.

If observer is not nil it may be used to control the authentication process.

This is a synchronous failable constructor. See g_dbus_connection_new() for the asynchronous version.

Parameters:

Returns:

  • (Gio::DBusConnection) —

    a GDBus::Connection or nil if error is set. Free with g_object_unref().

#peer_credentials ⇒ Gio::Credentials

Gets the credentials of the authenticated peer. This will always return nil unless connection acted as a server (e.g. %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER was passed) when set up and the client passed credentials as part of the authentication process.

In a message bus setup, the message bus is always the server and each application is a client. So this method will always return nil for message bus clients.

Returns:

  • (Gio::Credentials) —

    a #GCredentials or nil if not available. Do not free this object, it is owned by connection.

#register_object(object_path, interface_info, vtable, user_data, user_data_free_func) ⇒ Integer

Registers callbacks for exported objects at object_path with the D-Bus interface that is described in interface_info.

Calls to functions in vtable (and user_data_free_func) will happen in the

thread-default main context][g-main-context-push-thread-default

of the thread you are calling this method from.

Note that all #GVariant values passed to functions in vtable will match the signature given in interface_info - if a remote caller passes incorrect values, the ‘org.freedesktop.DBus.Error.InvalidArgs` is returned to the remote caller.

Additionally, if the remote caller attempts to invoke methods or access properties not mentioned in interface_info the ‘org.freedesktop.DBus.Error.UnknownMethod` resp. `org.freedesktop.DBus.Error.InvalidArgs` errors are returned to the caller.

It is considered a programming error if the GDBus::InterfaceGetPropertyFunc function in vtable returns a #GVariant of incorrect type.

If an existing callback is already registered at object_path and interface_name, then error is set to #G_IO_ERROR_EXISTS.

GDBus automatically implements the standard D-Bus interfaces org.freedesktop.DBus.Properties, org.freedesktop.DBus.Introspectable and org.freedesktop.Peer, so you don’t have to implement those for the objects you export. You can implement org.freedesktop.DBus.Properties yourself, e.g. to handle getting and setting of properties asynchronously.

Note that the reference count on interface_info will be incremented by 1 (unless allocated statically, e.g. if the reference count is -1, see g_dbus_interface_info_ref()) for as long as the object is exported. Also note that vtable will be copied.

See this [server] for an example of how to use this method.

Parameters:

  • object_path (String) —

    the object path to register at

  • interface_info (Gio::DBusInterfaceInfo) —

    introspection data for the interface

  • vtable (Gio::DBusInterfaceVTable) —

    a GDBus::InterfaceVTable to call into or nil

  • user_data (GObject) —

    data to pass to functions in vtable

  • user_data_free_func (GLib::DestroyNotify) —

    function to call when the object path is unregistered

Returns:

  • (Integer) —

    0 if error is set, otherwise a registration id (never 0) that can be used with g_dbus_connection_unregister_object()

#register_object_with_closures(object_path, interface_info, method_call_closure, get_property_closure, set_property_closure) ⇒ Integer

Version of g_dbus_connection_register_object() using closures instead of a GDBus::InterfaceVTable for easier binding in other languages. that can be used with g_dbus_connection_unregister_object() .

Parameters:

  • object_path (String) —

    The object path to register at.

  • interface_info (Gio::DBusInterfaceInfo) —

    Introspection data for the interface.

  • method_call_closure (GObject::Closure) —

    #GClosure for handling incoming method calls.

  • get_property_closure (GObject::Closure) —

    #GClosure for getting a property.

  • set_property_closure (GObject::Closure) —

    #GClosure for setting a property.

Returns:

  • (Integer) —

    0 if error is set, otherwise a registration id (never 0)

#register_subtree(object_path, vtable, flags, user_data, user_data_free_func) ⇒ Integer

Registers a whole subtree of dynamic objects.

The enumerate and introspection functions in vtable are used to convey, to remote callers, what nodes exist in the subtree rooted by object_path.

When handling remote calls into any node in the subtree, first the enumerate function is used to check if the node exists. If the node exists or the #G_DBUS_SUBTREE_FLAGS_DISPATCH_TO_UNENUMERATED_NODES flag is set the introspection function is used to check if the node supports the requested method. If so, the dispatch function is used to determine where to dispatch the call. The collected GDBus::InterfaceVTable and #gpointer will be used to call into the interface vtable for processing the request.

All calls into user-provided code will be invoked in the

thread-default main context][g-main-context-push-thread-default

of the thread you are calling this method from.

If an existing subtree is already registered at object_path or then error is set to #G_IO_ERROR_EXISTS.

Note that it is valid to register regular objects (using g_dbus_connection_register_object()) in a subtree registered with g_dbus_connection_register_subtree() - if so, the subtree handler is tried as the last resort. One way to think about a subtree handler is to consider it a fallback handler for object paths not registered via g_dbus_connection_register_object() or other bindings.

Note that vtable will be copied so you cannot change it after registration.

See this [server] for an example of how to use this method. that can be used with g_dbus_connection_unregister_subtree() .

Parameters:

  • object_path (String) —

    the object path to register the subtree at

  • vtable (Gio::DBusSubtreeVTable) —

    a GDBus::SubtreeVTable to enumerate, introspect and dispatch nodes in the subtree

  • flags (Gio::DBusSubtreeFlags) —

    flags used to fine tune the behavior of the subtree

  • user_data (GObject) —

    data to pass to functions in vtable

  • user_data_free_func (GLib::DestroyNotify) —

    function to call when the subtree is unregistered

Returns:

  • (Integer) —

    0 if error is set, otherwise a subtree registration id (never 0)

#remove_filter(filter_id) ⇒ nil

Removes a filter.

Note that since filters run in a different thread, there is a race condition where it is possible that the filter will be running even after calling g_dbus_connection_remove_filter(), so you cannot just free data that the filter might be using. Instead, you should pass a GDestroy::Notify to g_dbus_connection_add_filter(), which will be called when it is guaranteed that the data is no longer needed.

Parameters:

  • filter_id (Integer) —

    an identifier obtained from g_dbus_connection_add_filter()

Returns:

  • (nil)

#send_message(message, flags, out_serial) ⇒ TrueClass

Asynchronously sends message to the peer represented by connection.

Unless flags contain the %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag, the serial number will be assigned by connection and set on message via g_dbus_message_set_serial(). If out_serial is not nil, then the serial number used will be written to this location prior to submitting the message to the underlying transport.

If connection is closed then the operation will fail with %G_IO_ERROR_CLOSED. If message is not well-formed, the operation fails with %G_IO_ERROR_INVALID_ARGUMENT.

See this [server] and [client] for an example of how to use this low-level API to send and receive UNIX file descriptors.

Note that message must be unlocked, unless flags contain the %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag.

Parameters:

  • message (Gio::DBusMessage) —

    a GDBus::Message

  • flags (Gio::DBusSendMessageFlags) —

    flags affecting how the message is sent

  • out_serial (Integer) —

    return location for serial number assigned to message when sending it or nil

Returns:

  • (TrueClass) —

    true if the message was well-formed and queued for transmission, false if error is set

#send_message_with_reply(message, flags, timeout_msec, out_serial, cancellable, callback, user_data) ⇒ nil

Asynchronously sends message to the peer represented by connection.

Unless flags contain the %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag, the serial number will be assigned by connection and set on message via g_dbus_message_set_serial(). If out_serial is not nil, then the serial number used will be written to this location prior to submitting the message to the underlying transport.

If connection is closed then the operation will fail with %G_IO_ERROR_CLOSED. If cancellable is canceled, the operation will fail with %G_IO_ERROR_CANCELLED. If message is not well-formed, the operation fails with %G_IO_ERROR_INVALID_ARGUMENT.

This is an asynchronous method. When the operation is finished, callback will be invoked in the

thread-default main context][g-main-context-push-thread-default

of the thread you are calling this method from. You can then call g_dbus_connection_send_message_with_reply_finish() to get the result of the operation. See g_dbus_connection_send_message_with_reply_sync() for the synchronous version.

Note that message must be unlocked, unless flags contain the %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag.

See this [server] and [client] for an example of how to use this low-level API to send and receive UNIX file descriptors.

Parameters:

  • message (Gio::DBusMessage) —

    a GDBus::Message

  • flags (Gio::DBusSendMessageFlags) —

    flags affecting how the message is sent

  • timeout_msec (Integer) —

    the timeout in milliseconds, -1 to use the default timeout or %G_MAXINT for no timeout

  • out_serial (Integer) —

    return location for serial number assigned to message when sending it or nil

  • cancellable (Gio::Cancellable) —

    a #GCancellable or nil

  • callback (Gio::AsyncReadyCallback) —

    a GAsync::ReadyCallback to call when the request is satisfied or nil if you don’t care about the result

  • user_data (GObject) —

    The data to pass to callback

Returns:

  • (nil)

#send_message_with_reply_finish(res) ⇒ Gio::DBusMessage

Finishes an operation started with g_dbus_connection_send_message_with_reply().

Note that error is only set if a local in-process error occurred. That is to say that the returned GDBus::Message object may be of type %G_DBUS_MESSAGE_TYPE_ERROR. Use g_dbus_message_to_gerror() to transcode this to a #GError.

See this [server] and [client] for an example of how to use this low-level API to send and receive UNIX file descriptors.

Parameters:

  • res (Gio::AsyncResult) —

    a GAsync::Result obtained from the #GAsyncReadyCallback passed to g_dbus_connection_send_message_with_reply()

Returns:

#send_message_with_reply_sync(message, flags, timeout_msec, out_serial, cancellable) ⇒ Gio::DBusMessage

Synchronously sends message to the peer represented by connection and blocks the calling thread until a reply is received or the timeout is reached. See g_dbus_connection_send_message_with_reply() for the asynchronous version of this method.

Unless flags contain the %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag, the serial number will be assigned by connection and set on message via g_dbus_message_set_serial(). If out_serial is not nil, then the serial number used will be written to this location prior to submitting the message to the underlying transport.

If connection is closed then the operation will fail with %G_IO_ERROR_CLOSED. If cancellable is canceled, the operation will fail with %G_IO_ERROR_CANCELLED. If message is not well-formed, the operation fails with %G_IO_ERROR_INVALID_ARGUMENT.

Note that error is only set if a local in-process error occurred. That is to say that the returned GDBus::Message object may be of type %G_DBUS_MESSAGE_TYPE_ERROR. Use g_dbus_message_to_gerror() to transcode this to a #GError.

See this [server] and [client] for an example of how to use this low-level API to send and receive UNIX file descriptors.

Note that message must be unlocked, unless flags contain the %G_DBUS_SEND_MESSAGE_FLAGS_PRESERVE_SERIAL flag.

Parameters:

  • message (Gio::DBusMessage) —

    a GDBus::Message

  • flags (Gio::DBusSendMessageFlags) —

    flags affecting how the message is sent.

  • timeout_msec (Integer) —

    the timeout in milliseconds, -1 to use the default timeout or %G_MAXINT for no timeout

  • out_serial (Integer) —

    return location for serial number assigned to message when sending it or nil

  • cancellable (Gio::Cancellable) —

    a #GCancellable or nil

Returns:

  • (Gio::DBusMessage) —

    a locked GDBus::Message that is the reply to message or nil if error is set

#signal_subscribe(sender, interface_name, member, object_path, arg0, flags, callback, user_data, user_data_free_func) ⇒ Integer

Subscribes to signals on connection and invokes callback with a whenever the signal is received. Note that callback will be invoked in the

thread-default main context][g-main-context-push-thread-default

of the thread you are calling this method from.

If connection is not a message bus connection, sender must be nil.

If sender is a well-known name note that callback is invoked with the unique name for the owner of sender, not the well-known name as one would expect. This is because the message bus rewrites the name. As such, to avoid certain race conditions, users should be tracking the name owner of the well-known name and use that when processing the received signal.

If one of %G_DBUS_SIGNAL_FLAGS_MATCH_ARG0_NAMESPACE or %G_DBUS_SIGNAL_FLAGS_MATCH_ARG0_PATH are given, arg0 is interpreted as part of a namespace or path. The first argument of a signal is matched against that part as specified by D-Bus.

If user_data_free_func is non-nil, it will be called (in the thread-default main context of the thread you are calling this method from) at some point after user_data is no longer needed. (It is not guaranteed to be called synchronously when the signal is unsubscribed from, and may be called after connection has been destroyed.)

As callback is potentially invoked in a different thread from where it’s emitted, it’s possible for this to happen after g_dbus_connection_signal_unsubscribe() has been called in another thread. Due to this, user_data should have a strong reference which is freed with user_data_free_func, rather than pointing to data whose lifecycle is tied to the signal subscription. For example, if a #GObject is used to store the subscription ID from g_dbus_connection_signal_subscribe(), a strong reference to that #GObject must be passed to user_data, and g_object_unref() passed to user_data_free_func. You are responsible for breaking the resulting reference count cycle by explicitly unsubscribing from the signal when dropping the last external reference to the #GObject. Alternatively, a weak reference may be used.

It is guaranteed that if you unsubscribe from a signal using g_dbus_connection_signal_unsubscribe() from the same thread which made the corresponding g_dbus_connection_signal_subscribe() call, callback will not be invoked after g_dbus_connection_signal_unsubscribe() returns.

The returned subscription identifier is an opaque value which is guaranteed to never be zero.

This function can never fail.

Parameters:

  • sender (String) —

    sender name to match on (unique or well-known name) or nil to listen from all senders

  • interface_name (String) —

    D-Bus interface name to match on or nil to match on all interfaces

  • member (String) —

    D-Bus signal name to match on or nil to match on all signals

  • object_path (String) —

    object path to match on or nil to match on all object paths

  • arg0 (String) —

    contents of first string argument to match on or nil to match on all kinds of arguments

  • flags (Gio::DBusSignalFlags) —

    GDBus::SignalFlags describing how arg0 is used in subscribing to the signal

  • callback (Gio::DBusSignalCallback) —

    callback to invoke when there is a signal matching the requested data

  • user_data (GObject) —

    user data to pass to callback

  • user_data_free_func (GLib::DestroyNotify) —

    function to free user_data with when subscription is removed or nil

Returns:

  • (Integer) —

    a subscription identifier that can be used with g_dbus_connection_signal_unsubscribe()

#signal_unsubscribe(subscription_id) ⇒ nil

Unsubscribes from signals.

Note that there may still be D-Bus traffic to process (relating to this signal subscription) in the current thread-default GMain::Context after this function has returned. You should continue to iterate the GMain::Context until the GDestroy::Notify function passed to g_dbus_connection_signal_subscribe() is called, in order to avoid memory leaks through callbacks queued on the GMain::Context after it’s stopped being iterated.

Parameters:

  • subscription_id (Integer) —

    a subscription id obtained from g_dbus_connection_signal_subscribe()

Returns:

  • (nil)

#start_message_processing ⇒ nil

If connection was created with %G_DBUS_CONNECTION_FLAGS_DELAY_MESSAGE_PROCESSING, this method starts processing messages. Does nothing on if connection wasn’t created with this flag or if the method has already been called.

Returns:

  • (nil)

#stream ⇒ Gio::IOStream

The underlying #GIOStream used for I/O.

If this is passed on construction and is a GSocket::Connection, then the corresponding #GSocket will be put into non-blocking mode.

While the GDBus::Connection is active, it will interact with this stream from a worker thread, so it is not safe to interact with the stream directly.

Returns:

#stream=(stream) ⇒ Gio::IOStream

The underlying #GIOStream used for I/O.

If this is passed on construction and is a GSocket::Connection, then the corresponding #GSocket will be put into non-blocking mode.

While the GDBus::Connection is active, it will interact with this stream from a worker thread, so it is not safe to interact with the stream directly.

Parameters:

Returns:

#unexport_action_group(export_id) ⇒ nil

Reverses the effect of a previous call to g_dbus_connection_export_action_group().

It is an error to call this function with an ID that wasn’t returned from g_dbus_connection_export_action_group() or to call it with the same ID more than once.

Parameters:

  • export_id (Integer) —

    the ID from g_dbus_connection_export_action_group()

Returns:

  • (nil)

#unexport_menu_model(export_id) ⇒ nil

Reverses the effect of a previous call to g_dbus_connection_export_menu_model().

It is an error to call this function with an ID that wasn’t returned from g_dbus_connection_export_menu_model() or to call it with the same ID more than once.

Parameters:

  • export_id (Integer) —

    the ID from g_dbus_connection_export_menu_model()

Returns:

  • (nil)

#unique_name ⇒ String

The unique name as assigned by the message bus or nil if the connection is not open or not a message bus connection.

Returns:

  • (String) —

    unique-name

#unique_name=(unique_name) ⇒ String

The unique name as assigned by the message bus or nil if the connection is not open or not a message bus connection.

Parameters:

  • unique_name (String)

Returns:

  • (String) —

    unique-name

  • (String) —

    unique-name

#unregister_object(registration_id) ⇒ TrueClass

Unregisters an object.

Parameters:

  • registration_id (Integer) —

    a registration id obtained from g_dbus_connection_register_object()

Returns:

  • (TrueClass) —

    true if the object was unregistered, false otherwise

#unregister_subtree(registration_id) ⇒ TrueClass

Unregisters a subtree.

Parameters:

  • registration_id (Integer) —

    a subtree registration id obtained from g_dbus_connection_register_subtree()

Returns:

  • (TrueClass) —

    true if the subtree was unregistered, false otherwise