caf::io::middleman Class Reference

Manages brokers and network backends. More...

#include <middleman.hpp>

Inheritance diagram for caf::io::middleman:

Classes
struct	background_task
	Independent tasks that run in the background, usually in their own thread. More...
struct	metric_singletons_t
	Metrics that the middleman collects by default. More...

Public Types
using	background_task_ptr = std::unique_ptr< background_task >
using	backend_pointer = std::unique_ptr< network::multiplexer >
	Smart pointer for network::multiplexer.
using	backend_factory = std::function< backend_pointer()>
	Used to initialize the backend during construction.
Public Types inherited from caf::actor_system::module
enum	id_t {   scheduler ,   middleman ,   openssl_manager ,   network_manager ,   num_ids }

Public Member Functions
expected< uint16_t >	open (uint16_t port, const char *in=nullptr, bool reuse=false)
	Tries to open a port for other CAF instances to connect to.
expected< void >	close (uint16_t port)
	Closes port port regardless of whether an actor is published to it.
expected< node_id >	connect (std::string host, uint16_t port)
	Tries to connect to given node.
template<class Handle >
expected< uint16_t >	publish (Handle &&whom, uint16_t port, const char *in=nullptr, bool reuse=false)
	Tries to publish whom at port and returns either an error or the bound port.
expected< uint16_t >	publish_local_groups (uint16_t port, const char *in=nullptr, bool reuse=false)
	Makes all local groups accessible via network on address addr and port.
template<class Handle >
expected< void >	unpublish (const Handle &whom, uint16_t port=0)
	Unpublishes whom by closing port or all assigned ports if port == 0.
template<class ActorHandle = actor>
expected< ActorHandle >	remote_actor (std::string host, uint16_t port)
	Establish a new connection to the actor at host on given port.
expected< group >	remote_group (const std::string &group_locator)
	Tries to connect to a group that runs on a different node in the network.
expected< group >	remote_group (const std::string &group_identifier, const std::string &host, uint16_t port)
	Tries to connect to a group that runs on a different node in the network.
actor_system &	system ()
	Returns the enclosing actor system.
const actor_system_config &	config () const
	Returns the systemw-wide configuration.
middleman_actor	actor_handle ()
	Returns a handle to the actor managing the middleman singleton.
template<class Impl >
actor	named_broker (const std::string &name)
	Returns the broker associated with name or creates a new instance of type Impl.
template<class F >
void	run_later (F fun)
	Runs fun in the event loop of the middleman.
virtual network::multiplexer &	backend ()=0
	Returns the IO backend used by this middleman.
strong_actor_ptr	remote_lookup (std::string name, const node_id &nid)
	Returns the actor associated with name at nid or invalid_actor if nid is not connected or has no actor associated to this name.
template<class Handle >
expected< Handle >	remote_spawn (const node_id &nid, std::string name, message args, timespan timeout=timespan{std::chrono::minutes{1}})
template<class Handle , class Rep , class Period >
expected< Handle >	remote_spawn (const node_id &nid, std::string name, message args, std::chrono::duration< Rep, Period > timeout)
void	start () override
	Starts any background threads needed by the module.
void	stop () override
	Stops all background threads of the module.
void	init (actor_system_config &) override
	Allows the module to change the configuration of the actor system during startup.
id_t	id () const override
	Returns the identifier of this module.
void *	subtype_ptr () override
	Returns a pointer to the subtype.
void	monitor (const node_id &node, const actor_addr &observer) override
	Causes the module to send a node_down_msg to observer if this system loses connection to node.
void	demonitor (const node_id &node, const actor_addr &observer) override
	Causes the module remove one entry for observer from the list of actors that receive a node_down_msg if this system loses connection to node.
template<spawn_options Os = no_spawn_options, class F = std::function<void(broker*)>, class... Ts>
infer_handle_from_fun_t< F >	spawn_broker (F fun, Ts &&... xs)
	Spawns a new functor-based broker.
template<spawn_options Os = no_spawn_options, class F = std::function<void(broker*)>, class... Ts>
expected< infer_handle_from_fun_t< F > >	spawn_client (F fun, const std::string &host, uint16_t port, Ts &&... xs)
	Returns a new functor-based broker connected to host:port or an error.
template<spawn_options Os = no_spawn_options, class F = std::function<void(broker*)>, class... Ts>
expected< infer_handle_from_fun_t< F > >	spawn_server (F fun, uint16_t &port, Ts &&... xs)
	Spawns a new broker as server running on given port.
template<spawn_options Os = no_spawn_options, class F = std::function<void(broker*)>, class... Ts>
expected< infer_handle_from_fun_t< F > >	spawn_server (F fun, const uint16_t &port, Ts &&... xs)
	Spawns a new broker as server running on given port.
virtual void	monitor (const node_id &node, const actor_addr &observer)=0
	Causes the module to send a node_down_msg to observer if this system loses connection to node.
virtual void	demonitor (const node_id &node, const actor_addr &observer)=0
	Causes the module remove one entry for observer from the list of actors that receive a node_down_msg if this system loses connection to node.
Public Member Functions inherited from caf::actor_system::module
const char *	name () const noexcept
	Returns the human-readable name of the module.
virtual void	start ()=0
	Starts any background threads needed by the module.
virtual void	stop ()=0
	Stops all background threads of the module.
virtual void	init (actor_system_config &)=0
	Allows the module to change the configuration of the actor system during startup.
virtual id_t	id () const =0
	Returns the identifier of this module.
virtual void *	subtype_ptr ()=0
	Returns a pointer to the subtype.

Static Public Member Functions
static void	init_global_meta_objects ()
	Adds message types of the I/O module to the global meta object table.
static void	add_module_options (actor_system_config &cfg)
	Adds module-specific options to the config before loading the module.
static actor_system::module *	make (actor_system &, detail::type_list<>)
	Returns a middleman using the default network backend.
template<class Backend >
static actor_system::module *	make (actor_system &sys, detail::type_list< Backend >)

Protected Member Functions
	middleman (actor_system &sys)

Friends
class	actor_system

Detailed Description

Manages brokers and network backends.

Member Function Documentation

demonitor()

void caf::io::middleman::demonitor ( const node_id &  node, const actor_addr &  observer  )

overridevirtual

Causes the module remove one entry for observer from the list of actors that receive a node_down_msg if this system loses connection to node.

Each call to monitor requires one call to demonitor in order to unsubscribe the observer completely.

Implements caf::actor_system::networking_module.

id()

actor_system::module::id_t caf::io::middleman::id ( ) const

overridevirtual

Returns the identifier of this module.

Implements caf::actor_system::module.

init()

void caf::io::middleman::init ( actor_system_config &  )

overridevirtual

Allows the module to change the configuration of the actor system during startup.

Implements caf::actor_system::module.

monitor()

void caf::io::middleman::monitor ( const node_id &  node, const actor_addr &  observer  )

overridevirtual

Causes the module to send a node_down_msg to observer if this system loses connection to node.

Implements caf::actor_system::networking_module.

publish()

template<class Handle >

expected< uint16_t > caf::io::middleman::publish	(	Handle &&	whom,
		uint16_t	port,
		const char *	in = nullptr,
		bool	reuse = false
	)

Tries to publish whom at port and returns either an error or the bound port.

Parameters

whom	Actor that should be published at port.
port	Unused TCP port.
in	The IP address to listen to or INADDR_ANY if in == nullptr.
reuse	Create socket using SO_REUSEADDR.

Returns

The actual port the OS uses after bind(). If port == 0 the OS chooses a random high-level port.

publish_local_groups()

expected< uint16_t > caf::io::middleman::publish_local_groups	(	uint16_t	port,
		const char *	in = nullptr,
		bool	reuse = false
	)

Makes all local groups accessible via network on address addr and port.

Returns

The actual port the OS uses after bind(). If port == 0 the OS chooses a random high-level port.

remote_actor()

template<class ActorHandle = actor>

expected< ActorHandle > caf::io::middleman::remote_actor	(	std::string	host,
		uint16_t	port
	)

Establish a new connection to the actor at host on given port.

Parameters

host	Valid hostname or IP address.
port	TCP port.

Returns

An actor to the proxy instance representing a remote actor or an error.

remote_group() [1/2]

expected< group > caf::io::middleman::remote_group	(	const std::string &	group_identifier,
		const std::string &	host,
		uint16_t	port
	)

Tries to connect to a group that runs on a different node in the network.

Parameters

group_identifier	Unique identifier of the group.
host	Hostname or IP address of the remote CAF node.
port	TCP port for connecting to the group name server of the node.

We won't receive a second message, so we drop our behavior here to terminate the actor after both requests finish.

remote_group() [2/2]

expected< group > caf::io::middleman::remote_group

(

const std::string &

group_locator

)

Tries to connect to a group that runs on a different node in the network.

Parameters

group_locator

Locator in the format <group-name>@<host>:<port>.

remote_lookup()

strong_actor_ptr caf::io::middleman::remote_lookup	(	std::string	name,
		const node_id &	nid
	)

Returns the actor associated with name at nid or invalid_actor if nid is not connected or has no actor associated to this name.

Note

Blocks the caller until nid responded to the lookup or an error occurred.

run_later()

template<class F >

void caf::io::middleman::run_later

(

F

fun

)

Runs fun in the event loop of the middleman.

Note

This member function is thread-safe.

spawn_client()

template<spawn_options Os = no_spawn_options, class F = std::function<void(broker*)>, class... Ts>

expected< infer_handle_from_fun_t< F > > caf::io::middleman::spawn_client	(	F	fun,
		const std::string &	host,
		uint16_t	port,
		Ts &&...	xs
	)

Returns a new functor-based broker connected to host:port or an error.

Warning

Blocks the caller for the timespan of the connection process.

spawn_server() [1/2]

template<spawn_options Os = no_spawn_options, class F = std::function<void(broker*)>, class... Ts>

expected< infer_handle_from_fun_t< F > > caf::io::middleman::spawn_server	(	F	fun,
		const uint16_t &	port,
		Ts &&...	xs
	)

Spawns a new broker as server running on given port.

Warning

Blocks the caller until the server socket is initialized.

spawn_server() [2/2]

template<spawn_options Os = no_spawn_options, class F = std::function<void(broker*)>, class... Ts>

expected< infer_handle_from_fun_t< F > > caf::io::middleman::spawn_server	(	F	fun,
		uint16_t &	port,
		Ts &&...	xs
	)

Spawns a new broker as server running on given port.

Warning

Blocks the caller until the server socket is initialized.

start()

void caf::io::middleman::start ( )

overridevirtual

Starts any background threads needed by the module.

Implements caf::actor_system::module.

stop()

void caf::io::middleman::stop ( )

overridevirtual

Stops all background threads of the module.

Implements caf::actor_system::module.

subtype_ptr()

void * caf::io::middleman::subtype_ptr ( )

overridevirtual

Returns a pointer to the subtype.

Implements caf::actor_system::module.

unpublish()

template<class Handle >

expected< void > caf::io::middleman::unpublish	(	const Handle &	whom,
		uint16_t	port = 0
	)

Unpublishes whom by closing port or all assigned ports if port == 0.

Parameters

whom	Actor that should be unpublished at port.
port	TCP port.

---

The documentation for this class was generated from the following files:

• libcaf_io/caf/io/middleman.hpp
• libcaf_io/caf/io/middleman.cpp