A MessageHub connects to other hubs to form a simple peer-to-peer application-internal networking system for sending and receiving messages. More...

#include <MessageHub.h>

Inheritance diagram for Cogs::Network::MessageHub:

Public Types
using	MessageQueue = std::deque< Message::Ptr >

using	HubList = std::vector< MessageHub * >

Public Member Functions
	MessageHub (uint32_t ident=0)
	Constructs a new MessageHub instance and adds it to the global hub list.

virtual	~MessageHub ()
	Removes this MessageHub from the global list and cleans up all connections to and from this hub.

bool	addListener (MessageHub *hub, bool bidirectional=false)
	Adds the specified hub as a listener to this hub.

bool	addListener (uint32_t hubid, bool bidirectional=false)
	Attempts to add the hub with the given ID as a listener to this hub.

bool	listenTo (MessageHub *hub, bool bidirectional=false)
	Sets this MessageHub up to listen for messages from the specified hub.

bool	listenTo (uint32_t hubid, bool bidirectional=false)
	Sets up this MessageHub to listen for messages from the hub with the specified ID (if a matching hub can be found).

bool	removeListener (MessageHub *hub)
	Removes the specified hub as a listener to this hub.

bool	removeListener (uint32_t hubid)
	Removes the hub with the given ID as a listener to this hub.

void	removeAllListeners ()
	Removes all listeners from this hub.

void	disconnectFromSender (uint32_t hubid)
	Disconnects this hub from the specified hub to which it is listening.

void	disconnectFromAllSenders ()
	Disconnects this hub from all hubs to which it is listening.

virtual void	broadcastMessage (const Message::Ptr &message)
	Broadcast message to all hubs.

virtual void	sendMessage (const Message::Ptr &message)
	Send message to all hubs listening to this one.

virtual void	queueMessage (const Message::Ptr &message)
	Queue a message for this hub to process.

virtual bool	processMessages (size_t limit=noLimit)
	Process all queued messages for this hub.

virtual bool	isSendOnly () const

uint32_t	getID () const

size_t	getNoOfQueuedMessages ()
	Retrieves the number of messages currently awaiting processing by this hub.

void	flushQueuedMessages ()
	Flushes all pending messages from this hub without processing them.

Static Public Attributes
static constexpr size_t	noLimit = 10000000

Protected Member Functions
Message::Ptr	getNextMessage ()
	Retrieves the next pending message.

Private Member Functions
virtual void	processMessage (Message &)

void	addSender (MessageHub *sender)
	Adds the specified hub as a sender to which this hub is listening.

void	removeSender (const MessageHub *sender)
	Removes the specified hub from this hub's list of senders.

Private Attributes
MessageQueue	messages
	Messages waiting to be processed by this hub.

Mutex	messagesMutex
	Mutex for the above queue.

HubList	listeners
	List of hubs listening to our messages.

HubList	senders
	List of hubs to which we are listening.

Mutex	hubsMutex
	Mutex protecting the above lists.

uint32_t	id
	Our ID.

Detailed Description

A MessageHub connects to other hubs to form a simple peer-to-peer application-internal networking system for sending and receiving messages.

Messages can be sent from a hub to all listening hubs by calling sendMessage, or can be broadcast to all hubs with broadcastMessage. Occasionally it is necessary to insert a message directly into the queue of another hub (or even your own hub). This can be done by calling queueMessage directly.

Message processing by a hub must be performed periodically by explicitly calling processMessages which, in turn, will call the virtual function processMessage for each pending message. It therefore follows that processMessage must be implemented by a derived class to actually handle any incoming messages.

Member Typedef Documentation

◆ HubList

using Cogs::Network::MessageHub::HubList = std::vector< MessageHub* >

◆ MessageQueue

using Cogs::Network::MessageHub::MessageQueue = std::deque< Message::Ptr >

Constructor & Destructor Documentation

◆ MessageHub()

Cogs::Network::MessageHub::MessageHub ( uint32_t ident = 0 )

Constructs a new MessageHub instance and adds it to the global hub list.

Instances of MessageHub can send messages, but to receive messages a derived class must be created that overrides and implements the processMessage function. *============================================================================================

References Cogs::Network::allHubs(), and Cogs::Network::allHubsMutex().

◆ ~MessageHub()

Cogs::Network::MessageHub::~MessageHub ( )

virtual

Removes this MessageHub from the global list and cleans up all connections to and from this hub.

*============================================================================================

References Cogs::Network::allHubs(), and Cogs::Network::allHubsMutex().

Member Function Documentation

◆ addListener() [1/2]

bool Cogs::Network::MessageHub::addListener	(	MessageHub *	hub,
		bool	bidirectional = `false`
	)

Adds the specified hub as a listener to this hub.

If biDirectional is true, this hub will also be added as a listener to the other hub, thus creating a two way communication channel. *============================================================================================

References addListener(), and addSender().

Referenced by addListener(), and listenTo().

◆ addListener() [2/2]

bool Cogs::Network::MessageHub::addListener	(	uint32_t	hubid,
		bool	bidirectional = `false`
	)

Attempts to add the hub with the given ID as a listener to this hub.

If biDirectional is true, this hub will also be added as a listener to the other hub, thus creating a two way communication channel. *============================================================================================

References Cogs::Network::find().

◆ addSender()

void Cogs::Network::MessageHub::addSender ( MessageHub * sender )

private

Adds the specified hub as a sender to which this hub is listening.

Senders are stored so that a hub can gracefully disconnect itself from hubs to which it is listening when required. *============================================================================================

Referenced by addListener().

◆ broadcastMessage()

void Cogs::Network::MessageHub::broadcastMessage ( const Message::Ptr & message )

virtual

Broadcast message to all hubs.

Broadcasts a message globally to all hubs currently active.

This hub will be excluded from the broadcast. *============================================================================================

References Cogs::Network::allHubs(), and Cogs::Network::allHubsMutex().

◆ disconnectFromAllSenders()

void Cogs::Network::MessageHub::disconnectFromAllSenders ( )

Disconnects this hub from all hubs to which it is listening.

*============================================================================================

◆ disconnectFromSender()

void Cogs::Network::MessageHub::disconnectFromSender ( uint32_t hubid )

Disconnects this hub from the specified hub to which it is listening.

*============================================================================================

◆ flushQueuedMessages()

void Cogs::Network::MessageHub::flushQueuedMessages ( )

Flushes all pending messages from this hub without processing them.

*============================================================================================

◆ getID()

uint32_t Cogs::Network::MessageHub::getID ( ) const

inline

◆ getNextMessage()

Cogs::Network::Message::Ptr Cogs::Network::MessageHub::getNextMessage ( )

protected

Retrieves the next pending message.

Called by processMessages. *============================================================================================

Referenced by Cogs::Network::ConnectionHub::processOutgoing().

◆ getNoOfQueuedMessages()

size_t Cogs::Network::MessageHub::getNoOfQueuedMessages ( )

Retrieves the number of messages currently awaiting processing by this hub.

*============================================================================================

◆ isSendOnly()

virtual bool Cogs::Network::MessageHub::isSendOnly ( ) const

inlinevirtual

Reimplemented in Cogs::Network::SendOnlyMessageHub.

◆ listenTo() [1/2]

bool Cogs::Network::MessageHub::listenTo	(	MessageHub *	hub,
		bool	bidirectional = `false`
	)

Sets this MessageHub up to listen for messages from the specified hub.

*============================================================================================

References addListener().

◆ listenTo() [2/2]

bool Cogs::Network::MessageHub::listenTo	(	uint32_t	hubid,
		bool	bidirectional = `false`
	)

Sets up this MessageHub to listen for messages from the hub with the specified ID (if a matching hub can be found).

*============================================================================================

References Cogs::Network::find().

◆ processMessage()

virtual void Cogs::Network::MessageHub::processMessage ( Message & )

inlineprivatevirtual

◆ processMessages()

bool Cogs::Network::MessageHub::processMessages ( size_t limit = noLimit )

virtual

Process all queued messages for this hub.

Processes all messages that have been received by this MessageHub.

Returns true if any messages were processed.

This function should be called periodically by the owner of a MessageHub to ensure received messages are actually handled.

A MessageHub implementation must override the processdMessage function to receive and process incoming messages. *============================================================================================

◆ queueMessage()

void Cogs::Network::MessageHub::queueMessage ( const Message::Ptr & message )

virtual

Queue a message for this hub to process.

Directly add the specified message to the incoming queue of this hub.

Normally messages are sent from a hub to all its listeners using the sendMessage function. This function, however, allows you to directly input a message into the queue of a single hub. *============================================================================================

Reimplemented in Cogs::Network::SendOnlyMessageHub.

◆ removeAllListeners()

void Cogs::Network::MessageHub::removeAllListeners ( )

Removes all listeners from this hub.

*============================================================================================

◆ removeListener() [1/2]

bool Cogs::Network::MessageHub::removeListener ( MessageHub * hub )

Removes the specified hub as a listener to this hub.

*============================================================================================

References removeSender().

◆ removeListener() [2/2]

bool Cogs::Network::MessageHub::removeListener ( uint32_t hubid )

Removes the hub with the given ID as a listener to this hub.

*============================================================================================

References Cogs::Network::find().

◆ removeSender()

void Cogs::Network::MessageHub::removeSender ( const MessageHub * sender )

private

Removes the specified hub from this hub's list of senders.

*============================================================================================

Referenced by removeListener().

◆ sendMessage()

void Cogs::Network::MessageHub::sendMessage ( const Message::Ptr & message )

virtual

Send message to all hubs listening to this one.

Sends a message from this hub.

The message will be queued for later processing in all hubs that are listening to this hub. Hubs (or their owners) must call processMessages periodically to process any pending messages. *============================================================================================

Member Data Documentation

◆ hubsMutex

Mutex Cogs::Network::MessageHub::hubsMutex

private

Mutex protecting the above lists.

◆ id

uint32_t Cogs::Network::MessageHub::id

private

Our ID.

◆ listeners

HubList Cogs::Network::MessageHub::listeners

private

List of hubs listening to our messages.

◆ messages

MessageQueue Cogs::Network::MessageHub::messages

private

Messages waiting to be processed by this hub.

◆ messagesMutex

Mutex Cogs::Network::MessageHub::messagesMutex

private

Mutex for the above queue.

◆ noLimit

constexpr size_t Cogs::Network::MessageHub::noLimit = 10000000

staticconstexpr

◆ senders

HubList Cogs::Network::MessageHub::senders

private

List of hubs to which we are listening.

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

Source/Network/MessageHub.h
Source/Network/MessageHub.cpp

Public Types

Public Member Functions

Static Public Attributes

Protected Member Functions

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ HubList

◆ MessageQueue

Constructor & Destructor Documentation

◆ MessageHub()

◆ ~MessageHub()

Member Function Documentation

◆ addListener() [1/2]

◆ addListener() [2/2]

◆ addSender()

◆ broadcastMessage()

◆ disconnectFromAllSenders()

◆ disconnectFromSender()

◆ flushQueuedMessages()

◆ getID()

◆ getNextMessage()

◆ getNoOfQueuedMessages()

◆ isSendOnly()

◆ listenTo() [1/2]

◆ listenTo() [2/2]

◆ processMessage()

◆ processMessages()

◆ queueMessage()

◆ removeAllListeners()

◆ removeListener() [1/2]

◆ removeListener() [2/2]

◆ removeSender()

◆ sendMessage()

Member Data Documentation

◆ hubsMutex

◆ id

◆ listeners

◆ messages

◆ messagesMutex

◆ noLimit

◆ senders