caf::actor_companion Class Reference

An co-existing actor forwarding all messages through a user-defined callback to another object, thus serving as gateway to allow any object to interact with other actors. More...

#include <actor_companion.hpp>

Inheritance diagram for caf::actor_companion:

Public Types
using	signatures = none_t
	Required by spawn for type deduction.
using	behavior_type = behavior
	Required by spawn for type deduction.
using	lock_type = detail::shared_spinlock
	A shared lockable.
using	enqueue_handler = std::function< void(mailbox_element_ptr)>
	Delegates incoming messages to user-defined event loop.
using	on_exit_handler = std::function< void()>
	Callback for actor termination.
Public Types inherited from caf::local_actor
using	clock_type = std::chrono::steady_clock
	Defines a monotonic clock suitable for measuring intervals.

Public Member Functions
	actor_companion (actor_config &cfg)
bool	enqueue (mailbox_element_ptr ptr, execution_unit *host) override
	Enqueues a new message wrapped in a mailbox_element to the actor.
bool	enqueue (strong_actor_ptr src, message_id mid, message content, execution_unit *eu) override
	Enqueues a new message without forwarding stack to the channel.
void	launch (execution_unit *eu, bool lazy, bool hide) override
void	on_exit () override
	Can be overridden to perform cleanup code after an actor finished execution.
void	disconnect (exit_reason rsn=exit_reason::normal)
	Removes the handler for incoming messages and terminates the companion for exit reason rsn.
void	on_enqueue (enqueue_handler handler)
	Sets the handler for incoming messages.
void	on_exit (on_exit_handler handler)
	Sets the handler for incoming messages.
Public Member Functions inherited from caf::local_actor
	local_actor (actor_config &cfg)
void	on_destroy () override
	Cleans up any remaining state before the destructor is called.
void	setup_metrics ()
virtual void	launch (execution_unit *eu, bool lazy, bool hide)=0
clock_type::time_point	now () const noexcept
	Returns the current time.
disposable	request_response_timeout (timespan d, message_id mid)
	Requests a new timeout for mid.
template<class T , spawn_options Os = no_spawn_options, class... Ts>
infer_handle_from_class_t< T >	spawn (Ts &&... xs)
template<spawn_options Os = no_spawn_options, class F , class... Ts>
infer_handle_from_fun_t< F >	spawn (F fun, Ts &&... xs)
template<class T , spawn_options Os = no_spawn_options, class Groups , class... Ts>
actor	spawn_in_groups (const Groups &gs, Ts &&... xs)
template<class T , spawn_options Os = no_spawn_options, class... Ts>
actor	spawn_in_groups (std::initializer_list< group > gs, Ts &&... xs)
template<class T , spawn_options Os = no_spawn_options, class... Ts>
actor	spawn_in_group (const group &grp, Ts &&... xs)
template<spawn_options Os = no_spawn_options, class Groups , class F , class... Ts>
actor	spawn_in_groups (const Groups &gs, F fun, Ts &&... xs)
template<spawn_options Os = no_spawn_options, class F , class... Ts>
actor	spawn_in_groups (std::initializer_list< group > gs, F fun, Ts &&... xs)
template<spawn_options Os = no_spawn_options, class F , class... Ts>
actor	spawn_in_group (const group &grp, F fun, Ts &&... xs)
void	send_exit (const actor_addr &whom, error reason)
	Sends an exit message to whom.
void	send_exit (const strong_actor_ptr &whom, error reason)
	Sends an exit message to whom.
template<class ActorHandle >
void	send_exit (const ActorHandle &whom, error reason)
	Sends an exit message to whom.
execution_unit *	context () const noexcept
	Returns the execution unit currently used by this actor.
void	context (execution_unit *x) noexcept
	Sets the execution unit for this actor.
actor_system &	system () const noexcept
	Returns the hosting actor system.
const actor_system_config &	config () const noexcept
	Returns the config of the hosting actor system.
actor_clock &	clock () const noexcept
	Returns the clock of the actor system.
strong_actor_ptr &	current_sender () noexcept
	Returns a pointer to the sender of the current message.
message_id	current_message_id () noexcept
	Returns the ID of the current message.
message_id	take_current_message_id () noexcept
	Returns the ID of the current message and marks the ID stored in the current mailbox element as answered.
void	drop_current_message_id () noexcept
	Marks the current message ID as answered.
strong_actor_ptr	current_next_stage () noexcept
	Returns a pointer to the next stage from the forwarding path of the current message or nullptr if the path is empty.
strong_actor_ptr	take_current_next_stage ()
	Returns a pointer to the next stage from the forwarding path of the current message and removes it from the path.
const mailbox_element::forwarding_stack &	current_forwarding_stack () noexcept
	Returns the forwarding stack from the current mailbox element.
mailbox_element::forwarding_stack	take_current_forwarding_stack () noexcept
	Moves the forwarding stack from the current mailbox element.
mailbox_element *	current_mailbox_element () noexcept
	Returns a pointer to the currently processed mailbox element.
void	monitor (const node_id &node)
	Adds a unidirectional monitor to node.
template<message_priority P = message_priority::normal, class Handle >
void	monitor (const Handle &whom)
	Adds a unidirectional monitor to whom.
void	demonitor (const actor_addr &whom)
	Removes a monitor from whom.
void	demonitor (const strong_actor_ptr &whom)
	Removes a monitor from whom.
void	demonitor (const node_id &node)
	Removes a monitor from node.
template<class Handle >
void	demonitor (const Handle &whom)
	Removes a monitor from whom.
virtual void	on_exit ()
	Can be overridden to perform cleanup code after an actor finished execution.
template<class... Ts>
detail::response_promise_t< Ts... >	make_response_promise ()
	Creates a typed_response_promise to respond to a request later on.
response_promise	make_response_promise ()
	Creates a response_promise to respond to a request later on.
const char *	name () const override
	Returns an implementation-dependent name for logging purposes, which is only valid as long as the actor is running.
virtual error	save_state (serializer &sink, unsigned int version)
	Serializes the state of this actor to sink.
virtual error	load_state (deserializer &source, unsigned int version)
	Deserializes the state of this actor from source.
const error &	fail_state () const noexcept
	Returns the currently defined fail state.
Public Member Functions inherited from caf::monitorable_actor
virtual const char *	name () const
	Returns an implementation-dependent name for logging purposes, which is only valid as long as the actor is running.
void	attach (attachable_ptr ptr) override
	Attaches ptr to this actor.
size_t	detach (const attachable::token &what) override
	Detaches the first attached object that matches what.
void	link_to (const actor_addr &x)
	Links this actor to x.
template<class ActorHandle >
void	link_to (const ActorHandle &x)
	Links this actor to x.
void	unlink_from (const actor_addr &x)
	Unlinks this actor from x.
template<class ActorHandle >
void	unlink_from (const ActorHandle &x)
	Links this actor to x.
Public Member Functions inherited from caf::abstract_actor
actor_control_block *	ctrl () const
	abstract_actor (const abstract_actor &)=delete
abstract_actor &	operator= (const abstract_actor &)=delete
virtual void	on_destroy ()
	Cleans up any remaining state before the destructor is called.
bool	enqueue (strong_actor_ptr sender, message_id mid, message msg, execution_unit *host) override
	Enqueues a new message without forwarding stack to the channel.
virtual bool	enqueue (mailbox_element_ptr what, execution_unit *host)=0
	Enqueues a new message wrapped in a mailbox_element to the actor.
virtual void	attach (attachable_ptr ptr)=0
	Attaches ptr to this actor.
template<class F >
void	attach_functor (F f)
	Convenience function that attaches the functor f to this actor.
actor_addr	address () const noexcept
	Returns the logical actor address.
virtual size_t	detach (const attachable::token &what)=0
	Detaches the first attached object that matches what.
virtual std::set< std::string >	message_types () const
	Returns the set of accepted messages types as strings or an empty set if this actor is untyped.
actor_id	id () const noexcept
	Returns the ID of this actor.
node_id	node () const noexcept
	Returns the node this actor is living on.
actor_system &	home_system () const noexcept
	Returns the system that created this actor (or proxy).
Public Member Functions inherited from caf::abstract_channel
virtual bool	enqueue (strong_actor_ptr sender, message_id mid, message content, execution_unit *host=nullptr)=0
	Enqueues a new message without forwarding stack to the channel.
bool	is_abstract_actor () const
bool	is_abstract_group () const
bool	is_actor_decorator () const

Additional Inherited Members
Static Public Attributes inherited from caf::abstract_channel
static constexpr int	is_abstract_actor_flag = 0x01000000
static constexpr int	is_abstract_group_flag = 0x02000000
static constexpr int	is_actor_bind_decorator_flag = 0x04000000
static constexpr int	is_actor_dot_decorator_flag = 0x08000000
static constexpr int	is_actor_decorator_mask = 0x0C000000
static constexpr int	is_hidden_flag = 0x10000000
Protected Member Functions inherited from caf::monitorable_actor
virtual void	on_cleanup (const error &reason)
	Allows subclasses to add additional cleanup code to the critical section in cleanup.
void	bounce (mailbox_element_ptr &what)
	Sends a response message if what is a request.
void	bounce (mailbox_element_ptr &what, const error &err)
	Sends a response message if what is a request.
	monitorable_actor (actor_config &cfg)
	Creates a new actor instance.
void	attach_impl (attachable_ptr &ptr)
size_t	detach_impl (const attachable::token &what, bool stop_on_hit=false, bool dry_run=false)
bool	handle_system_message (mailbox_element &x, execution_unit *ctx, bool trap_exit)
template<class F >
bool	handle_system_message (mailbox_element &x, execution_unit *context, bool trap_exit, F &down_msg_handler)
Protected Member Functions inherited from caf::abstract_actor
	abstract_actor (actor_config &cfg)
Protected Member Functions inherited from caf::abstract_channel
int	flags () const
void	flags (int new_value)
Protected Attributes inherited from caf::local_actor
execution_unit *	context_
mailbox_element *	current_element_
message_id	last_request_id_
detail::unique_function< behavior(local_actor *)>	initial_behavior_fac_
	Factory function for returning initial behavior in function-based actors.
metrics_t	metrics_
Protected Attributes inherited from caf::monitorable_actor
error	fail_state_
std::condition_variable	cv_
attachable_ptr	attachables_head_
Protected Attributes inherited from caf::abstract_actor
std::mutex	mtx_
Related Functions inherited from caf::local_actor
constexpr keep_behavior_t	keep_behavior = keep_behavior_t{}
	Policy tag that causes event_based_actor::become to keep the current behavior available.
Related Functions inherited from caf::abstract_actor
using	actor_id = uint64_t
	A unique actor ID.

Detailed Description

An co-existing actor forwarding all messages through a user-defined callback to another object, thus serving as gateway to allow any object to interact with other actors.

Member Function Documentation

enqueue() [1/2]

bool caf::actor_companion::enqueue ( mailbox_element_ptr  what, execution_unit *  host  )

overridevirtual

Enqueues a new message wrapped in a mailbox_element to the actor.

This enqueue variant allows to define forwarding chains.

Returns

true if the message has added to the mailbox, false otherwise. In the latter case, the actor terminated and the message has been dropped. Once this function returns false, it returns false for all future invocations.

Note

The returned value is purely informational and may be used to discard actor handles early. Messages may still get dropped later even if this function returns true. In particular when dealing with remote actors.

Implements caf::abstract_actor.

enqueue() [2/2]

bool caf::actor_companion::enqueue ( strong_actor_ptr  sender, message_id  mid, message  content, execution_unit *  host  )

overridevirtual

Enqueues a new message without forwarding stack to the channel.

Returns

true if the message has been dispatches successful, false otherwise. In the latter case, the channel has been closed and the message has been dropped. Once this function returns false, it returns false for all future invocations.

Reimplemented from caf::abstract_actor.

launch()

void caf::actor_companion::launch ( execution_unit *  eu, bool  lazy, bool  hide  )

overridevirtual

Implements caf::local_actor.

on_enqueue()

void caf::actor_companion::on_enqueue

(

enqueue_handler

handler

)

Sets the handler for incoming messages.

Warning

handler needs to be thread-safe

on_exit()

void caf::actor_companion::on_exit ( )

overridevirtual

Can be overridden to perform cleanup code after an actor finished execution.

Reimplemented from caf::local_actor.

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

• libcaf_core/caf/actor_companion.hpp