SocketListener

Added in version 2.22.

class SocketListener(**properties: Any)

Superclasses: Object

Subclasses: SocketService

A GSocketListener is an object that keeps track of a set of server sockets and helps you accept sockets from any of the socket, either sync or async.

Add addresses and ports to listen on using add_address and add_inet_port. These will be listened on until close is called. Dropping your final reference to the GSocketListener will not cause close to be called implicitly, as some references to the GSocketListener may be held internally.

If you want to implement a network server, also look at SocketService and ThreadedSocketService which are subclasses of GSocketListener that make this even easier.

Constructors

class SocketListener
classmethod new() → SocketListener

Creates a new SocketListener with no sockets to listen for. New listeners can be added with e.g. add_address() or add_inet_port().

Added in version 2.22.

Methods

class SocketListener
accept(cancellable: Cancellable | None = None) → tuple[SocketConnection, Object]

Blocks waiting for a client to connect to any of the sockets added to the listener. Returns a SocketConnection for the socket that was accepted.

If source_object is not None it will be filled out with the source object specified when the corresponding socket or address was added to the listener.

If cancellable is not None, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error CANCELLED will be returned.

Added in version 2.22.

Parameters:

cancellable – optional Cancellable object, None to ignore.

accept_async(cancellable: Cancellable | None = None, callback: Callable[[...], None] | None = None, *user_data: Any) → None

This is the asynchronous version of accept().

When the operation is finished callback will be called. You can then call accept_finish() to get the result of the operation.

Added in version 2.22.

Parameters:

  • cancellable – a Cancellable, or None

  • callback – a AsyncReadyCallback

  • user_data – user data for the callback

accept_finish(result: AsyncResult) → tuple[SocketConnection, Object]

Finishes an async accept operation. See accept_async()

Added in version 2.22.

Parameters:

result – a AsyncResult.

accept_socket(cancellable: Cancellable | None = None) → tuple[Socket, Object]

Blocks waiting for a client to connect to any of the sockets added to the listener. Returns the Socket that was accepted.

If you want to accept the high-level SocketConnection, not a Socket, which is often the case, then you should use accept() instead.

If source_object is not None it will be filled out with the source object specified when the corresponding socket or address was added to the listener.

If cancellable is not None, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error CANCELLED will be returned.

Added in version 2.22.

Parameters:

cancellable – optional Cancellable object, None to ignore.

accept_socket_async(cancellable: Cancellable | None = None, callback: Callable[[...], None] | None = None, *user_data: Any) → None

This is the asynchronous version of accept_socket().

When the operation is finished callback will be called. You can then call accept_socket_finish() to get the result of the operation.

Added in version 2.22.

Parameters:

  • cancellable – a Cancellable, or None

  • callback – a AsyncReadyCallback

  • user_data – user data for the callback

accept_socket_finish(result: AsyncResult) → tuple[Socket, Object]

Finishes an async accept operation. See accept_socket_async()

Added in version 2.22.

Parameters:

result – a AsyncResult.

add_address(address: SocketAddress, type: SocketType, protocol: SocketProtocol, source_object: Object | None = None) → tuple[bool, SocketAddress]

Creates a socket of type type and protocol protocol, binds it to address and adds it to the set of sockets we’re accepting sockets from.

Note that adding an IPv6 address, depending on the platform, may or may not result in a listener that also accepts IPv4 connections. For more deterministic behavior, see add_inet_port().

source_object will be passed out in the various calls to accept to identify this particular source, which is useful if you’re listening on multiple addresses and do different things depending on what address is connected to.

If successful and effective_address is non-None then it will be set to the address that the binding actually occurred at. This is helpful for determining the port number that was used for when requesting a binding to port 0 (ie: “any port”). This address, if requested, belongs to the caller and must be freed.

Call close() to stop listening on address; this will not be done automatically when you drop your final reference to listener, as references may be held internally.

Added in version 2.22.

Parameters:
add_any_inet_port(source_object: Object | None = None) → int

Listens for TCP connections on any available port number for both IPv6 and IPv4 (if each is available).

This is useful if you need to have a socket for incoming connections but don’t care about the specific port number.

source_object will be passed out in the various calls to accept to identify this particular source, which is useful if you’re listening on multiple addresses and do different things depending on what address is connected to.

Added in version 2.24.

Parameters:

source_object – Optional Object identifying this source

add_inet_port(port: int, source_object: Object | None = None) → bool

Helper function for add_address() that creates a TCP/IP socket listening on IPv4 and IPv6 (if supported) on the specified port on all interfaces.

source_object will be passed out in the various calls to accept to identify this particular source, which is useful if you’re listening on multiple addresses and do different things depending on what address is connected to.

Call close() to stop listening on port; this will not be done automatically when you drop your final reference to listener, as references may be held internally.

Added in version 2.22.

Parameters:

  • port – an IP port number (non-zero)

  • source_object – Optional Object identifying this source

add_socket(socket: Socket, source_object: Object | None = None) → bool

Adds socket to the set of sockets that we try to accept new clients from. The socket must be bound to a local address and listened to.

source_object will be passed out in the various calls to accept to identify this particular source, which is useful if you’re listening on multiple addresses and do different things depending on what address is connected to.

The socket will not be automatically closed when the listener is finalized unless the listener held the final reference to the socket. Before GLib 2.42, the socket was automatically closed on finalization of the listener, even if references to it were held elsewhere.

Added in version 2.22.

Parameters:

  • socket – a listening Socket

  • source_object – Optional Object identifying this source

close() → None

Closes all the sockets in the listener.

Added in version 2.22.

set_backlog(listen_backlog: int) → None

Sets the listen backlog on the sockets in the listener. This must be called before adding any sockets, addresses or ports to the SocketListener (for example, by calling add_inet_port()) to be effective.

See set_listen_backlog() for details

Added in version 2.22.

Parameters:

listen_backlog – an integer

Properties

class SocketListener
props.listen_backlog: int

The number of outstanding connections in the listen queue.

Added in version 2.22.

Signals

class SocketListener.signals
event(event: SocketListenerEvent, socket: Socket) → None

Emitted when listener’s activity on socket changes state. Note that when listener is used to listen on both IPv4 and IPv6, a separate set of signals will be emitted for each, and the order they happen in is undefined.

Added in version 2.46.

Parameters:

  • event – the event that is occurring

  • socket – the Socket the event is occurring on

Virtual Methods

class SocketListener
do_changed() → None
do_event(event: SocketListenerEvent, socket: Socket) → None
Parameters:

  • event

  • socket

Fields

class SocketListener
parent_instance
priv