mysql_harness::logging Namespace Reference

Namespaces
namespace	options
	option name used in config file (and later in configuration object) to specify log level.

Classes
class	DomainLogger
class	ExternalHandler
	Acts as an actual represenation of external handler attached to ExternalHandlerProxy to handle logging. More...
class	ExternalHandlerProxy
	Acts as a placeholder for a handler that can be attached later (does not log until this is done). More...
class	FileHandler
	Handler that writes to a file. More...
class	Handler
	Base class for log message handler. More...
class	Logger
	Logger class. More...
class	NullHandler
	Handler to write to a null device such as /dev/null (unix) or NUL (windows). More...
struct	Record
	Log record containing information collected by the logging system. More...
class	Registry
class	StreamHandler
	Handler to write to an output stream. More...

Enumerations
enum class	LogLevel {   kFatal , kSystem , kError , kWarning ,   kInfo , kNote , kDebug , kNotSet }
	Log level values. More...
enum class	LogTimestampPrecision {   kSec = 0 , kMilliSec = 3 , kMicroSec = 6 , kNanoSec = 9 ,   kNotSet }
	Log timestamp precision values. More...

Functions
HARNESS_EXPORT bool	log_level_is_handled (LogLevel level, const char *domain)
static bool	log_level_is_handled (LogLevel level)
HARNESS_EXPORT LogLevel	log_level_from_string (std::string name)
	Converts string with log level description to LogLevel type. More...
HARNESS_EXPORT std::string	log_level_to_string (LogLevel log_level)
	Converts LogLevel type to its string name. More...
HARNESS_EXPORT LogLevel	get_default_log_level (const Config &config, bool raw_mode=false)
	Get default log level. More...
HARNESS_EXPORT std::string	get_default_log_filename (const Config &config)
	Get default log filename. More...
HARNESS_EXPORT void	attach_handler_to_all_loggers (Registry &registry, std::string name)
	Attach handler to all loggers. More...
HARNESS_EXPORT void	set_log_level_for_all_loggers (Registry &registry, LogLevel level)
	Set log levels for all the loggers to specified value. More...
HARNESS_EXPORT void	set_log_level_for_handler (std::string name, LogLevel level)
	Set log level for selected handler to specified value. More...
HARNESS_EXPORT void	set_log_level_for_all_handlers (const Registry &registry, LogLevel level)
	Set log levels for all handlers to specified value. More...
HARNESS_EXPORT LogTimestampPrecision	log_timestamp_precision_from_string (std::string name)
	Converts string with log timestamp precision description to LogTimestampPrecision type. More...
HARNESS_EXPORT std::string	log_timestamp_precision_to_string (LogTimestampPrecision tsp)
HARNESS_EXPORT LogTimestampPrecision	get_default_timestamp_precision (const Config &config)
	Get default timestamp precision. More...
HARNESS_EXPORT void	set_timestamp_precision_for_all_loggers (Registry &registry, LogTimestampPrecision precision)
	Set timestamp precision for all the loggers. More...
HARNESS_EXPORT void	clear_registry (Registry &registry)
	Clear registry. More...
HARNESS_EXPORT void	create_module_loggers (Registry &registry, const LogLevel level, const std::list< std::string > &modules, const std::string &main_app_log_domain)
	Initialize logging facility. More...
HARNESS_EXPORT void	create_logger (Registry &registry, const LogLevel level, const std::string &logger_name)
HARNESS_EXPORT void	create_main_log_handler (Registry &registry, const std::string &program, const std::string &logging_folder, bool format_messages, bool use_os_log=false)
	Initialize logfile handler. More...
HARNESS_EXPORT void	set_log_level_for_all_loggers (LogLevel level)
	Set log level for all registered loggers. More...
HARNESS_EXPORT void	set_log_level_for_all_handlers (LogLevel level)
	Set log level for all registered handlers. More...
HARNESS_EXPORT void	set_timestamp_precison_for_all_loggers (LogTimestampPrecision precision)
	Set timestamp precision for all registered loggers. More...
HARNESS_EXPORT void	register_handler (std::string name, std::shared_ptr< Handler > handler)
	Register handler for all plugins. More...
HARNESS_EXPORT void	unregister_handler (std::string name)
	Unregister a handler. More...
HARNESS_EXPORT bool	handler_registered (std::string name)
	Returns true if a given handler is in the registry, false otherwise. More...
HARNESS_EXPORT std::ostream *	get_default_logger_stream ()
	Returns pointer to the default logger sink stream. More...
void	set_timestamp_precision_for_all_loggers (LogTimestampPrecision precision)
static void	log_system (const char *fmt,...) ATTRIBUTE_GCC_FORMAT(printf
static void static void	log_error (const char *fmt,...) ATTRIBUTE_GCC_FORMAT(printf
static void static void static void	log_warning (const char *fmt,...) ATTRIBUTE_GCC_FORMAT(printf
static void static void static void static void	log_info (const char *fmt,...) ATTRIBUTE_GCC_FORMAT(printf
static void static void static void static void static void	log_note (const char *fmt,...) ATTRIBUTE_GCC_FORMAT(printf
static void static void static void static void static void static void	log_debug (const char *fmt,...) ATTRIBUTE_GCC_FORMAT(printf
static void static void static void static void static void static void static void	log_custom (const LogLevel log_level, const char *fmt,...) ATTRIBUTE_GCC_FORMAT(printf

Variables
const size_t	kLogMessageMaxSize = 4096
	Max message length that can be logged; if message is longer, it will be truncated to this length. More...
constexpr char	kConfigSectionLogger [] = "logger"
constexpr char	kNone [] = ""
constexpr char	kMainLogger [] = "main"
	Special names reserved for "main" program logger. More...
constexpr char	kMainLogHandler [] = "main_log_handler"
constexpr char	kMainConsoleHandler [] = "main_console_handler"
constexpr char	kSqlLogger [] = "sql"
constexpr char	kDefaultLogFilename [] = "mysqlrouter.log"
	Default log filename. More...
const LogLevel	kDefaultLogLevel = LogLevel::kWarning
	Default log level used by the router. More...
const LogLevel	kDefaultLogLevelBootstrap = LogLevel::kInfo
	Default log level written by the router to the config file on bootstrap. More...
const char *const	kDefaultLogLevelName = "warning"
	Log level name for the default log level used by the router. More...
const char *const	kRawLogLevelName = "info"
	Log level name used in raw logging mode. More...
static std::string	g_main_app_log_domain

Enumeration Type Documentation

LogLevel

enum class mysql_harness::logging::LogLevel

strong

Log level values.

Log levels are ordered numerically from most important (lowest value) to least important (highest value).

Enumerator
kFatal	Fatal failure. Router usually exits after logging this.
kSystem	System message. These messages are always logged, such as state changes during startup and shutdown.
kError	Error message. indicate that something is not working properly and actions need to be taken. However, the router continue operating but the particular thread issuing the error message might terminate.
kWarning	Warning message. Indicate a potential problem that could require actions, but does not cause a problem for the continuous operation of the router.
kInfo	Informational message. Information that can be useful to check the behaviour of the router during normal operation.
kNote	Note level contains additional information over the normal informational messages.
kDebug	Debug message. Message contain internal details that can be useful for debugging problematic situations, especially regarding the router itself.
kNotSet

LogTimestampPrecision

enum class mysql_harness::logging::LogTimestampPrecision

strong

Log timestamp precision values.

Enumerator
kSec
kMilliSec
kMicroSec
kNanoSec
kNotSet

Function Documentation

attach_handler_to_all_loggers()

void mysql_harness::logging::attach_handler_to_all_loggers	(	Registry &	registry,
		std::string	name
	)

Attach handler to all loggers.

Parameters

registry	Registry object, typically managed by DIM
name	Logger id (log domain it services)

clear_registry()

void mysql_harness::logging::clear_registry

(

Registry &

registry

)

Clear registry.

Removes all Loggers and removes all references to Handlers (they're held as shared pointers, which may mean they will also be deleted)

Parameters

registry

Registry object, typically managed by DIM

create_logger()

void mysql_harness::logging::create_logger	(	Registry &	registry,
		const LogLevel	level,
		const std::string &	logger_name
	)

create_main_log_handler()

void mysql_harness::logging::create_main_log_handler	(	Registry &	registry,
		const std::string &	program,
		const std::string &	logging_folder,
		bool	format_messages,
		bool	use_os_log = false
	)

Initialize logfile handler.

Initializes handler which will handle application's log. This handler will be attached to all currently-registered loggers. If logging_folder is provided, handler will log messages to logfile; its path and filename will be derived from program and logging_folder parameters. If logging_folder is empty, handler will log messages to console, unless use_os_log is set to true, in which case it will log to system logger instead (i.e. Syslog, Windows Eventlog, etc. Currently, only Windows Eventlog is supported).

Parameters

registry	Registry object, typically managed by DIM
program	Name of the main program (Router)
logging_folder	logging_folder provided in configuration file
format_messages	If set to true, log messages will be formatted (prefixed with log level, timestamp, etc) before logging
use_os_log	If true, use system logger instead of STDERR (currently, only Windows Eventlog is supported)

Exceptions

std::runtime_error

if opening log file or OS log fails

create_module_loggers()

void mysql_harness::logging::create_module_loggers	(	Registry &	registry,
		const LogLevel	level,
		const std::list< std::string > &	modules,
		const std::string &	main_app_log_domain
	)

Initialize logging facility.

Initializes logging facility by creating and registering a logger for each given module. Loggers will have their log level set to the log level passed as a parameter.

Note

Loggers will not have any handlers attached, this needs to be done separately (see create_main_log_handler())

Parameters

registry	Registry object, typically managed by DIM
level	The log level of the logger
modules	List of plugin names loaded
main_app_log_domain	Log domain (logger id) to be used as the main program logger. This logger must exist, because log_*() functions might fail

Exceptions

std::logic_error

On error.

get_default_log_filename()

std::string mysql_harness::logging::get_default_log_filename

(

const Config &

config

)

Get default log filename.

Fetches default log filename set in the configuration file

Parameters

config

Configuration items from configuration file

get_default_log_level()

LogLevel mysql_harness::logging::get_default_log_level	(	const Config &	config,
		bool	raw_mode = false
	)

Get default log level.

Fetches default log level set in the configuration file

Parameters

config	Configuration items from configuration file
raw_mode	true if the default level should be for the raw mode, false otherwise

Exceptions

std::invalid_argument

if [logger].level in configuration is invalid

get_default_logger_stream()

std::ostream * mysql_harness::logging::get_default_logger_stream

(

)

Returns pointer to the default logger sink stream.

get_default_timestamp_precision()

LogTimestampPrecision mysql_harness::logging::get_default_timestamp_precision

(

const Config &

config

)

Get default timestamp precision.

Fetches default timestamp precision for logfiles

Parameters

config

Configuration items from configuration file

handler_registered()

bool mysql_harness::logging::handler_registered

(

std::string

name

)

Returns true if a given handler is in the registry, false otherwise.

Parameters

name	name of the handler to check.

log_custom()

static void mysql_harness::logging::log_custom ( const LogLevel  log_level, const char *  fmt,   ...  )

inlinestatic

log_debug()

static void mysql_harness::logging::log_debug ( const char *  fmt,   ...  )

inlinestatic

log_error()

static void mysql_harness::logging::log_error ( const char *  fmt,   ...  )

inlinestatic

log_info()

static void mysql_harness::logging::log_info ( const char *  fmt,   ...  )

inlinestatic

log_level_from_string()

LogLevel mysql_harness::logging::log_level_from_string

(

std::string

name

)

Converts string with log level description to LogLevel type.

Parameters

name	string with log level description

Exceptions

std::invalid_argument

if log level string is invalid

log_level_is_handled() [1/2]

static bool mysql_harness::logging::log_level_is_handled ( LogLevel  level )

inlinestatic

log_level_is_handled() [2/2]

bool mysql_harness::logging::log_level_is_handled	(	LogLevel	level,
		const char *	domain
	)

log_level_to_string()

std::string mysql_harness::logging::log_level_to_string

(

LogLevel

log_level

)

Converts LogLevel type to its string name.

Parameters

log_level

value to convert

log_note()

static void mysql_harness::logging::log_note ( const char *  fmt,   ...  )

inlinestatic

log_system()

static void static void static void static void static void static void static void static void mysql_harness::logging::log_system ( const char *  fmt,   ...  )

inlinestatic

log_timestamp_precision_from_string()

LogTimestampPrecision mysql_harness::logging::log_timestamp_precision_from_string

(

std::string

name

)

Converts string with log timestamp precision description to LogTimestampPrecision type.

Parameters

name	string with log timestamp precision description

Exceptions

std::invalid_argument

if log timestamp precision string is invalid

log_timestamp_precision_to_string()

std::string mysql_harness::logging::log_timestamp_precision_to_string

(

LogTimestampPrecision

tsp

)

log_warning()

static void mysql_harness::logging::log_warning ( const char *  fmt,   ...  )

inlinestatic

register_handler()

void mysql_harness::logging::register_handler	(	std::string	name,
		std::shared_ptr< Handler >	handler
	)

Register handler for all plugins.

This will register a handler for all plugins that have been registered with the logging subsystem (normally all plugins that have been loaded by Loader).

Parameters

name	The name under which handler is registered
handler	Shared pointer to dynamically allocated handler.

For example, to register a custom handler from a plugin, you would do the following:

void init() {
  ...
  register_handler(std::make_shared<MyHandler>(...));
  ...
}

set_log_level_for_all_handlers() [1/2]

void mysql_harness::logging::set_log_level_for_all_handlers	(	const Registry &	registry,
		LogLevel	level
	)

Set log levels for all handlers to specified value.

Parameters

registry	Registry object, typically managed by DIM
level	Log level for logger

set_log_level_for_all_handlers() [2/2]

void mysql_harness::logging::set_log_level_for_all_handlers

(

LogLevel

level

)

Set log level for all registered handlers.

set_log_level_for_all_loggers() [1/2]

void mysql_harness::logging::set_log_level_for_all_loggers

(

LogLevel

level

)

Set log level for all registered loggers.

set_log_level_for_all_loggers() [2/2]

void mysql_harness::logging::set_log_level_for_all_loggers	(	Registry &	registry,
		LogLevel	level
	)

Set log levels for all the loggers to specified value.

Parameters

registry	Registry object, typically managed by DIM
level	Log level for logger

set_log_level_for_handler()

void mysql_harness::logging::set_log_level_for_handler	(	std::string	name,
		LogLevel	level
	)

Set log level for selected handler to specified value.

Parameters

name	Name of the registry in the singleton (DIM)
level	Log level for handler

set_timestamp_precision_for_all_loggers() [1/2]

void mysql_harness::logging::set_timestamp_precision_for_all_loggers

(

LogTimestampPrecision

precision

)

set_timestamp_precision_for_all_loggers() [2/2]

void mysql_harness::logging::set_timestamp_precision_for_all_loggers	(	Registry &	registry,
		LogTimestampPrecision	precision
	)

Set timestamp precision for all the loggers.

Parameters

registry	Registry object, typically managed by DIM
precision	Precision of timestamps

set_timestamp_precison_for_all_loggers()

HARNESS_EXPORT void mysql_harness::logging::set_timestamp_precison_for_all_loggers

(

LogTimestampPrecision

precision

)

Set timestamp precision for all registered loggers.

unregister_handler()

void mysql_harness::logging::unregister_handler

(

std::string

name

)

Unregister a handler.

This will unregister a previously registered handler.

Parameters

name	name of registered handler.

Variable Documentation

g_main_app_log_domain

std::string mysql_harness::logging::g_main_app_log_domain

static

kConfigSectionLogger

constexpr char mysql_harness::logging::kConfigSectionLogger[] = "logger"

constexpr

kDefaultLogFilename

constexpr char mysql_harness::logging::kDefaultLogFilename[] = "mysqlrouter.log"

constexpr

Default log filename.

kDefaultLogLevel

const LogLevel mysql_harness::logging::kDefaultLogLevel = LogLevel::kWarning

Default log level used by the router.

kDefaultLogLevelBootstrap

const LogLevel mysql_harness::logging::kDefaultLogLevelBootstrap = LogLevel::kInfo

Default log level written by the router to the config file on bootstrap.

kDefaultLogLevelName

const char* const mysql_harness::logging::kDefaultLogLevelName = "warning"

Log level name for the default log level used by the router.

kLogMessageMaxSize

const size_t mysql_harness::logging::kLogMessageMaxSize = 4096

Max message length that can be logged; if message is longer, it will be truncated to this length.

kMainConsoleHandler

constexpr char mysql_harness::logging::kMainConsoleHandler[] = "main_console_handler"

constexpr

kMainLogger

constexpr char mysql_harness::logging::kMainLogger[] = "main"

constexpr

Special names reserved for "main" program logger.

It will use one of the two handlers, depending on whether logging_folder is empty or not.

kMainLogHandler

constexpr char mysql_harness::logging::kMainLogHandler[] = "main_log_handler"

constexpr

kNone

constexpr char mysql_harness::logging::kNone[] = ""

constexpr

kRawLogLevelName

const char* const mysql_harness::logging::kRawLogLevelName = "info"

Log level name used in raw logging mode.

kSqlLogger

constexpr char mysql_harness::logging::kSqlLogger[] = "sql"

constexpr