class Gio::DBusConnection

Overview

The #GDBusConnection 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, #GDBusConnection'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 #GDBusConnection when called from any thread.

Most of the ways to obtain a #GDBusConnection 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 #GDBusConnection, 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 #GDBusConnection 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 #GDBusConnection 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

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

Here is an example for exporting a subtree: 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

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

Here is an example for exporting a #GObject: gdbus-example-export.c

Included Modules

Defined in:

lib/gi-crystal/src/auto/gio-2.0/d_bus_connection.cr

Constructors

Class Method Summary

Instance Method Summary

Instance methods inherited from module Gio::Initable

init(cancellable : Gio::Cancellable?) : Bool init, newv(object_type : UInt64, parameters : Enumerable(GObject::Parameter), cancellable : Gio::Cancellable?) : GObject::Object newv, to_unsafe to_unsafe

Class methods inherited from module Gio::Initable

g_type : UInt64 g_type

Instance methods inherited from module Gio::AsyncInitable

init_async(io_priority : Int32, cancellable : Gio::Cancellable?, callback : Gio::AsyncReadyCallback?, user_data : Pointer(Void)?) : Nil init_async, init_finish(res : Gio::AsyncResult) : Bool init_finish, new_finish(res : Gio::AsyncResult) : GObject::Object new_finish, to_unsafe to_unsafe

Class methods inherited from module Gio::AsyncInitable

g_type : UInt64 g_type, newv_async(object_type : UInt64, n_parameters : UInt32, parameters : GObject::Parameter, io_priority : Int32, cancellable : Gio::Cancellable?, callback : Gio::AsyncReadyCallback?, user_data : Pointer(Void)?) : Nil newv_async

Instance methods inherited from class GObject::Object

bind_property(source_property : String, target : GObject::Object, target_property : String, flags : GObject::BindingFlags) : GObject::Binding bind_property, bind_property_full(source_property : String, target : GObject::Object, target_property : String, flags : GObject::BindingFlags, transform_to : GObject::Closure, transform_from : GObject::Closure) : GObject::Binding bind_property_full, data(key : String) : Pointer(Void)? data, finalize finalize, freeze_notify : Nil freeze_notify, getv(names : Enumerable(String), values : Enumerable(_)) : Nil getv, notify(property_name : String) : Nil notify, notify_by_pspec(pspec : GObject::ParamSpec) : Nil notify_by_pspec, notify_signal notify_signal, property(property_name : String, value : _) : Nil property, qdata(quark : UInt32) : Pointer(Void)? qdata, ref_count : UInt32 ref_count, run_dispose : Nil run_dispose, set_data(key : String, data : Pointer(Void)?) : Nil set_data, set_property(property_name : String, value : _) : Nil set_property, steal_data(key : String) : Pointer(Void)? steal_data, steal_qdata(quark : UInt32) : Pointer(Void)? steal_qdata, thaw_notify : Nil thaw_notify, to_unsafe : Pointer(Void) to_unsafe, watch_closure(closure : GObject::Closure) : Nil watch_closure

Constructor methods inherited from class GObject::Object

cast(obj : GObject::Object) : self cast, cast?(obj : GObject::Object) : self? cast?, new(pointer : Pointer(Void), transfer : GICrystal::Transfer)
new
new
, newv(object_type : UInt64, parameters : Enumerable(GObject::Parameter)) : self newv

Class methods inherited from class GObject::Object

compat_control(what : UInt64, data : Pointer(Void)?) : UInt64 compat_control, g_type : UInt64 g_type, interface_find_property(g_iface : GObject::TypeInterface, property_name : String) : GObject::ParamSpec interface_find_property, interface_list_properties(g_iface : GObject::TypeInterface) : Enumerable(GObject::ParamSpec) interface_list_properties

Constructor Detail

def self.new(stream : Gio::IOStream, guid : String?, flags : Gio::DBusConnectionFlags, observer : Gio::DBusAuthObserver?, cancellable : Gio::Cancellable?, callback : Gio::AsyncReadyCallback?, user_data : Pointer(Void)?) : Nil #

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

If @stream is a #GSocketConnection, 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 %NULL it may be used to control the authentication process.

When the operation is finished, @callback will be invoked. You can then call g_dbus_connection_new_finish() to get the result of the operation.

This is an asynchronous failable constructor. See g_dbus_connection_new_sync() for the synchronous version.


def self.new #

Initialize a new DBusConnection.


def self.new(*, address : String? = nil, authentication_observer : Gio::DBusAuthObserver? = nil, capabilities : Gio::DBusCapabilityFlags? = nil, closed : Bool? = nil, exit_on_close : Bool? = nil, flags : Gio::DBusConnectionFlags? = nil, guid : String? = nil, stream : Gio::IOStream? = nil, unique_name : String? = nil) #

def self.new_finish(res : Gio::AsyncResult) : self #

Finishes an operation started with g_dbus_connection_new().


def self.new_for_address_finish(res : Gio::AsyncResult) : self #

Finishes an operation started with g_dbus_connection_new_for_address().


def self.new_for_address_sync(address : String, flags : Gio::DBusConnectionFlags, observer : Gio::DBusAuthObserver?, cancellable : Gio::Cancellable?) : self #

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.

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, %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_ALLOW_ANONYMOUS or %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_REQUIRE_SAME_USER flags.

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

If @observer is not %NULL it may be used to control the authentication process.


def self.new_sync(stream : Gio::IOStream, guid : String?, flags : Gio::DBusConnectionFlags, observer : Gio::DBusAuthObserver?, cancellable : Gio::Cancellable?) : self #

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

If @stream is a #GSocketConnection, 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 %NULL it may be used to control the authentication process.

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


Class Method Detail

def self.g_type : UInt64 #

Returns the type id (GType) registered in GLib type system.


def self.new_for_address(address : String, flags : Gio::DBusConnectionFlags, observer : Gio::DBusAuthObserver?, cancellable : Gio::Cancellable?, callback : Gio::AsyncReadyCallback?, user_data : Pointer(Void)?) : Nil #

Asynchronously 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.

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

When the operation is finished, @callback will be invoked. You can then call g_dbus_connection_new_for_address_finish() to get the result of the operation.

If @observer is not %NULL it may be used to control the authentication process.

This is an asynchronous failable constructor. See g_dbus_connection_new_for_address_sync() for the synchronous version.


Instance Method Detail

def add_filter(filter_function : Gio::DBusMessageFilterFunction) : UInt32 #

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-%NULL, 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.)


def address=(value : String) : String #

def authentication_observer=(value : Gio::DBusAuthObserver?) : Gio::DBusAuthObserver? #

def call(bus_name : String?, object_path : String, interface_name : String, method_name : String, parameters : _?, reply_type : GLib::VariantType?, flags : Gio::DBusCallFlags, timeout_msec : Int32, cancellable : Gio::Cancellable?, callback : Gio::AsyncReadyCallback?, user_data : Pointer(Void)?) : 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-%NULL 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-%NULL 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 %NULL then the D-Bus method call message will be sent with the %G_DBUS_MESSAGE_FLAGS_NO_REPLY_EXPECTED flag set.


def call_finish(res : Gio::AsyncResult) : GLib::Variant #

Finishes an operation started with g_dbus_connection_call().


def call_sync(bus_name : String?, object_path : String, interface_name : String, method_name : String, parameters : _?, reply_type : GLib::VariantType?, flags : Gio::DBusCallFlags, timeout_msec : Int32, cancellable : Gio::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-%NULL 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-%NULL 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.


def call_with_unix_fd_list(bus_name : String?, object_path : String, interface_name : String, method_name : String, parameters : _?, reply_type : GLib::VariantType?, flags : Gio::DBusCallFlags, timeout_msec : Int32, fd_list : Gio::UnixFDList?, cancellable : Gio::Cancellable?, callback : Gio::AsyncReadyCallback?, user_data : Pointer(Void)?) : Nil #

Like g_dbus_connection_call() but also takes a #GUnixFDList object.

The file descriptors normally correspond to %G_VARIANT_TYPE_HANDLE values in the body of the message. For example, if a message contains two file descriptors, @fd_list would have length 2, and g_variant_new_handle (0) and g_variant_new_handle (1) would appear somewhere in the body of the message (not necessarily in that order!) to represent the file descriptors at indexes 0 and 1 respectively.

When designing D-Bus APIs that are intended to be interoperable, please note that non-GDBus implementations of D-Bus can usually only access file descriptors if they are referenced in this way by a value of type %G_VARIANT_TYPE_HANDLE in the body of the message.

This method is only available on UNIX.


def call_with_unix_fd_list_finish(res : Gio::AsyncResult) : GLib::Variant #

Finishes an operation started with g_dbus_connection_call_with_unix_fd_list().

The file descriptors normally correspond to %G_VARIANT_TYPE_HANDLE values in the body of the message. For example, if g_variant_get_handle() returns 5, that is intended to be a reference to the file descriptor that can be accessed by g_unix_fd_list_get (*out_fd_list, 5, ...).

When designing D-Bus APIs that are intended to be interoperable, please note that non-GDBus implementations of D-Bus can usually only access file descriptors if they are referenced in this way by a value of type %G_VARIANT_TYPE_HANDLE in the body of the message.


def call_with_unix_fd_list_sync(bus_name : String?, object_path : String, interface_name : String, method_name : String, parameters : _?, reply_type : GLib::VariantType?, flags : Gio::DBusCallFlags, timeout_msec : Int32, fd_list : Gio::UnixFDList?, cancellable : Gio::Cancellable?) : GLib::Variant #

Like g_dbus_connection_call_sync() but also takes and returns #GUnixFDList objects. See g_dbus_connection_call_with_unix_fd_list() and g_dbus_connection_call_with_unix_fd_list_finish() for more details.

This method is only available on UNIX.


def capabilities : Gio::DBusCapabilityFlags #

Gets the capabilities negotiated with the remote peer


def close(cancellable : Gio::Cancellable?, callback : Gio::AsyncReadyCallback?, user_data : Pointer(Void)?) : 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 #GDBusConnection: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 #GDBusConnection::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.


def close_finish(res : Gio::AsyncResult) : Bool #

Finishes an operation started with g_dbus_connection_close().


def close_sync(cancellable : Gio::Cancellable?) : Bool #

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.


def closed? : Bool #

def closed_signal #

def emit_signal(destination_bus_name : String?, object_path : String, interface_name : String, signal_name : String, parameters : _?) : Bool #

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).


def exit_on_close : Bool #

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


def exit_on_close=(exit_on_close : Bool) : Nil #

Sets whether the process should be terminated when @connection is closed by the remote peer. See #GDBusConnection:exit-on-close for more details.

Note that this function should be used with care. Most modern UNIX desktops tie the notion of a user session with the session bus, and expect all of a user's applications to quit when their bus connection goes away. If you are setting @exit_on_close to %FALSE for the shared session bus connection, you should make sure that your application exits when the user session ends.


def exit_on_close? : Bool #

def export_action_group(object_path : String, action_group : Gio::ActionGroup) : UInt32 #

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.


def export_menu_model(object_path : String, menu : Gio::MenuModel) : UInt32 #

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.


Gets the flags used to construct this connection



def flush(cancellable : Gio::Cancellable?, callback : Gio::AsyncReadyCallback?, user_data : Pointer(Void)?) : 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.


def flush_finish(res : Gio::AsyncResult) : Bool #

Finishes an operation started with g_dbus_connection_flush().


def flush_sync(cancellable : Gio::Cancellable?) : Bool #

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.


def guid : String #

The GUID of the peer performing the role of server when authenticating. See #GDBusConnection:guid for more details.


def guid=(value : String) : String #

def is_closed : Bool #

Gets whether @connection is closed.


def last_serial : UInt32 #

Retrieves the last serial number assigned to a #GDBusMessage 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().


def peer_credentials : Gio::Credentials? #

Gets the credentials of the authenticated peer. This will always return %NULL 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 %NULL for message bus clients.


def register_object(object_path : String, interface_info : Gio::DBusInterfaceInfo, method_call_closure : GObject::Closure?, get_property_closure : GObject::Closure?, set_property_closure : GObject::Closure?) : UInt32 #

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 #GDBusInterfaceGetPropertyFunc 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][gdbus-server] for an example of how to use this method.


def register_subtree(object_path : String, vtable : Gio::DBusSubtreeVTable, flags : Gio::DBusSubtreeFlags, user_data : Pointer(Void)?, user_data_free_func : GLib::DestroyNotify) : UInt32 #

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 #GDBusInterfaceVTable 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][gdbus-subtree-server] for an example of how to use this method.


def remove_filter(filter_id : UInt32) : 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 #GDestroyNotify to g_dbus_connection_add_filter(), which will be called when it is guaranteed that the data is no longer needed.


def send_message(message : Gio::DBusMessage, flags : Gio::DBusSendMessageFlags) : Bool #

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 %NULL, then the serial number used will be written to this location prior to submitting the message to the underlying transport. While it has a volatile qualifier, this is a historical artifact and the argument passed to it should not be volatile.

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][gdbus-server] and [client][gdbus-unix-fd-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.


def send_message_with_reply(message : Gio::DBusMessage, flags : Gio::DBusSendMessageFlags, timeout_msec : Int32, cancellable : Gio::Cancellable?, callback : Gio::AsyncReadyCallback?, user_data : Pointer(Void)?) : 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 %NULL, then the serial number used will be written to this location prior to submitting the message to the underlying transport. While it has a volatile qualifier, this is a historical artifact and the argument passed to it should not be volatile.

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


def send_message_with_reply_finish(res : Gio::AsyncResult) : 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 #GDBusMessage 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][gdbus-server] and [client][gdbus-unix-fd-client] for an example of how to use this low-level API to send and receive UNIX file descriptors.


def send_message_with_reply_sync(message : Gio::DBusMessage, flags : Gio::DBusSendMessageFlags, timeout_msec : Int32, cancellable : Gio::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 %NULL, then the serial number used will be written to this location prior to submitting the message to the underlying transport. While it has a volatile qualifier, this is a historical artifact and the argument passed to it should not be volatile.

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 #GDBusMessage 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][gdbus-server] and [client][gdbus-unix-fd-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.


def signal_subscribe(sender : String?, interface_name : String?, member : String?, object_path : String?, arg0 : String?, flags : Gio::DBusSignalFlags, callback : Gio::DBusSignalCallback) : UInt32 #

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 %NULL.

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-%NULL, 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.


def signal_unsubscribe(subscription_id : UInt32) : 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 #GMainContext after this function has returned. You should continue to iterate the #GMainContext until the #GDestroyNotify function passed to g_dbus_connection_signal_subscribe() is called, in order to avoid memory leaks through callbacks queued on the #GMainContext after it’s stopped being iterated. Alternatively, any idle source with a priority lower than %G_PRIORITY_DEFAULT that was scheduled after unsubscription, also indicates that all resources of this subscription are released.


def 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.


def stream : Gio::IOStream #

Gets the underlying stream used for IO.

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


def stream=(value : Gio::IOStream?) : Gio::IOStream? #

def unexport_action_group(export_id : UInt32) : 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.


def unexport_menu_model(export_id : UInt32) : 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.


def unique_name : String? #

Gets the unique name of @connection as assigned by the message bus. This can also be used to figure out if @connection is a message bus connection.


def unregister_object(registration_id : UInt32) : Bool #

Unregisters an object.


def unregister_subtree(registration_id : UInt32) : Bool #

Unregisters a subtree.