Asynchronous background logging service executing on a dedicated C++20 std::jthread. Consumes/flushes log events or periodic status messages asynchronously without blocking the main event loop. More...

#include <LogBackgroundService.hpp>

Inheritance diagram for corium::logging::LogBackgroundService< LogSink, EventVariant, MaxMessageSize >:

Collaboration diagram for corium::logging::LogBackgroundService< LogSink, EventVariant, MaxMessageSize >:

Public Types
using	Base = Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >

using	EventVariant = typename Base::EventVariant

using	IncomingBus = BasicEventBus< EventVariant, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >

using	LoggerType = LoggerT< LogSink, MaxMessageSize >

Public Member Functions
template<typename... Args>
void	info (const char *fmt, Args &&... args) const
	Log background heartbeat or event message.

void	join () noexcept
	Join background std::jthread cleanly.

	LogBackgroundService (const char *category="LogService", LogLevel minLevel=LogLevel::Info, LogSink sink=LogSink{})

const LoggerType &	logger () const noexcept

LoggerType &	logger () noexcept
	Access embedded logger instance.

EventSinkT< EventVariant >	mainSink () const noexcept
	Get an EventSink handle targeting the main application event queue.

template<typename Handler >
bool	on (Handler &&handler)
	Register an event handler for incoming events with automatic event type deduction.

bool	processOne ()
	Process a single incoming event from the service queue.

std::size_t	pump ()
	Pump all pending incoming events from the queue until empty.

std::size_t	pump (std::size_t maxEvents)
	Pump up to maxEvents pending incoming events from the queue.

template<typename EventType , typename Handler >
bool	registerHandler (Handler &&handler)
	Register an event handler for incoming events with explicit event type parameter.

void	run (const std::stop_token &stopToken)
	Main background execution loop.

void	setContext (ServiceContextT< EventVariant > context) noexcept

EventSinkT< EventVariant >	sink () noexcept
	Get an EventSink handle targeting this service's incoming event queue.

template<typename Derived >
void	startThread (Derived *derived)
	Start execution loop on dedicated std::jthread.

void	stop () noexcept
	Request cancellation on worker std::jthread.

template<typename Rep , typename Period >
std::size_t	waitAndPump (const std::stop_token &stopToken, const std::chrono::duration< Rep, Period > &timeout)
	Wait for incoming events or timeout, then pump all available incoming events. Safe for use inside worker thread run(std::stop_token).

Protected Member Functions
const ServiceContextT< EventVariant > &	context () const noexcept

ServiceContextT< EventVariant > &	context () noexcept

const IncomingBus &	incomingBus () const noexcept

IncomingBus &	incomingBus () noexcept

template<typename EventType >
void	post (EventType &&event, EventPriority priority=EventPriority::Normal) const
	Post an event into the main application event queue.

template<typename EventType >
void	postHighPriority (EventType &&event) const
	Post a high-priority event into the main application event queue.

template<typename TargetService , typename EventType >
bool	sendToService (EventType &&event, EventPriority priority=EventPriority::Normal) const
	Post an event directly to another registered service.

Detailed Description

template<typename LogSink = sinks::ConsoleLogSink, typename EventVariant = DefaultEvents, std::size_t MaxMessageSize = 256>
class corium::logging::LogBackgroundService< LogSink, EventVariant, MaxMessageSize >

Asynchronous background logging service executing on a dedicated C++20 std::jthread. Consumes/flushes log events or periodic status messages asynchronously without blocking the main event loop.

Template Parameters

LogSink	Log sink backend type (e.g. ConsoleLogSink, FileLogSink, NullLogSink).
EventVariant	Event variant list supported by the runtime context.
MaxMessageSize	Inline capacity size for log events.

Member Typedef Documentation

◆ Base

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

using corium::BackgroundService< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::Base = Service<EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy>

inherited

◆ EventVariant

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

using corium::BackgroundService< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::EventVariant = typename Base::EventVariant

inherited

◆ IncomingBus

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

using corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::IncomingBus = BasicEventBus<EventVariant, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy>

inherited

◆ LoggerType

template<typename LogSink = sinks::ConsoleLogSink, typename EventVariant = DefaultEvents, std::size_t MaxMessageSize = 256>

using corium::logging::LogBackgroundService< LogSink, EventVariant, MaxMessageSize >::LoggerType = LoggerT<LogSink, MaxMessageSize>

Constructor & Destructor Documentation

◆ LogBackgroundService()

template<typename LogSink = sinks::ConsoleLogSink, typename EventVariant = DefaultEvents, std::size_t MaxMessageSize = 256>

corium::logging::LogBackgroundService< LogSink, EventVariant, MaxMessageSize >::LogBackgroundService	(	const char *	category = `"LogService"`,
		LogLevel	minLevel = `LogLevel::Info`,
		LogSink	sink = `LogSink{}`
	)

inlineexplicit

Member Function Documentation

◆ context() [1/2]

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

const ServiceContextT< EventVariant > & corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::context ( ) const

inlineprotectednoexceptinherited

◆ context() [2/2]

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

ServiceContextT< EventVariant > & corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::context ( )

inlineprotectednoexceptinherited

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◆ incomingBus() [1/2]

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

const IncomingBus & corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::incomingBus ( ) const

inlineprotectednoexceptinherited

◆ incomingBus() [2/2]

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

IncomingBus & corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::incomingBus ( )

inlineprotectednoexceptinherited

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◆ info()

template<typename LogSink = sinks::ConsoleLogSink, typename EventVariant = DefaultEvents, std::size_t MaxMessageSize = 256>

template<typename... Args>

void corium::logging::LogBackgroundService< LogSink, EventVariant, MaxMessageSize >::info	(	const char *	fmt,
		Args &&...	args
	)		const

inline

Log background heartbeat or event message.

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◆ join()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

void corium::BackgroundService< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::join ( )

inlinenoexceptinherited

Join background std::jthread cleanly.

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◆ logger() [1/2]

template<typename LogSink = sinks::ConsoleLogSink, typename EventVariant = DefaultEvents, std::size_t MaxMessageSize = 256>

const LoggerType & corium::logging::LogBackgroundService< LogSink, EventVariant, MaxMessageSize >::logger ( ) const

inlinenoexcept

◆ logger() [2/2]

template<typename LogSink = sinks::ConsoleLogSink, typename EventVariant = DefaultEvents, std::size_t MaxMessageSize = 256>

LoggerType & corium::logging::LogBackgroundService< LogSink, EventVariant, MaxMessageSize >::logger ( )

inlinenoexcept

Access embedded logger instance.

◆ mainSink()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

EventSinkT< EventVariant > corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::mainSink ( ) const

inlinenoexceptinherited

Get an EventSink handle targeting the main application event queue.

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◆ on()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

template<typename Handler >

bool corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::on ( Handler && handler )

inlineinherited

Register an event handler for incoming events with automatic event type deduction.

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◆ post()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

template<typename EventType >

void corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::post	(	EventType &&	event,
		EventPriority	priority = `EventPriority::Normal`
	)		const

inlineprotectedinherited

Post an event into the main application event queue.

◆ postHighPriority()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

template<typename EventType >

void corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::postHighPriority ( EventType && event ) const

inlineprotectedinherited

Post a high-priority event into the main application event queue.

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◆ processOne()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

bool corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::processOne ( )

inlineinherited

Process a single incoming event from the service queue.

Returns: true if an event was popped and dispatched; false if queue was empty.

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◆ pump() [1/2]

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

std::size_t corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::pump ( )

inlineinherited

Pump all pending incoming events from the queue until empty.

Returns: Number of events processed.

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◆ pump() [2/2]

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

std::size_t corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::pump ( std::size_t maxEvents )

inlineinherited

Pump up to maxEvents pending incoming events from the queue.

Parameters

maxEvents Maximum number of events to process.

Returns: Number of events processed.

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◆ registerHandler()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

template<typename EventType , typename Handler >

bool corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::registerHandler ( Handler && handler )

inlineinherited

Register an event handler for incoming events with explicit event type parameter.

◆ run()

template<typename LogSink = sinks::ConsoleLogSink, typename EventVariant = DefaultEvents, std::size_t MaxMessageSize = 256>

void corium::logging::LogBackgroundService< LogSink, EventVariant, MaxMessageSize >::run ( const std::stop_token & stopToken )

inline

Main background execution loop.

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◆ sendToService()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

template<typename TargetService , typename EventType >

bool corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::sendToService	(	EventType &&	event,
		EventPriority	priority = `EventPriority::Normal`
	)		const

inlineprotectedinherited

Post an event directly to another registered service.

◆ setContext()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

void corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::setContext ( ServiceContextT< EventVariant > context )

inlinenoexceptinherited

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◆ sink()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

EventSinkT< EventVariant > corium::Service< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::sink ( )

inlinenoexceptinherited

Get an EventSink handle targeting this service's incoming event queue.

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◆ startThread()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

template<typename Derived >

void corium::BackgroundService< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::startThread ( Derived * derived )

inlineinherited

Start execution loop on dedicated std::jthread.

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◆ stop()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

void corium::BackgroundService< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::stop ( )

inlinenoexceptinherited

Request cancellation on worker std::jthread.

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◆ waitAndPump()

template<typename EventVariantType = DefaultEvents, typename QueuePolicy = BoundedMpscQueuePolicy<EventVariantType, 1024>, typename SignalPolicy = CallbackSignalPolicy, typename StoragePolicy = DefaultStoragePolicy, typename OverflowPolicy = DropNewestOverflowPolicy>

template<typename Rep , typename Period >

std::size_t corium::BackgroundService< EventVariantType, QueuePolicy, SignalPolicy, StoragePolicy, OverflowPolicy >::waitAndPump	(	const std::stop_token &	stopToken,
		const std::chrono::duration< Rep, Period > &	timeout
	)

inlineinherited

Wait for incoming events or timeout, then pump all available incoming events. Safe for use inside worker thread run(std::stop_token).

Template Parameters

Rep	Duration representation type.
Period	Duration period type.

Parameters

stopToken	std::stop_token from run(stopToken).
timeout	Maximum duration to wait if queue is empty.

Returns: Number of events processed.

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

include/corium/logging/LogBackgroundService.hpp

Public Types

Public Member Functions

Protected Member Functions

Detailed Description

Member Typedef Documentation

◆ Base

◆ EventVariant

◆ IncomingBus

◆ LoggerType

Constructor & Destructor Documentation

◆ LogBackgroundService()

Member Function Documentation

◆ context() [1/2]

◆ context() [2/2]

◆ incomingBus() [1/2]

◆ incomingBus() [2/2]

◆ info()

◆ join()

◆ logger() [1/2]

◆ logger() [2/2]

◆ mainSink()

◆ on()

◆ post()

◆ postHighPriority()

◆ processOne()

◆ pump() [1/2]

◆ pump() [2/2]

◆ registerHandler()

◆ run()

◆ sendToService()

◆ setContext()

◆ sink()

◆ startThread()

◆ stop()

◆ waitAndPump()