Option_usage_data Class Reference

A helper class to handle option usage population. More...

#include <option_usage_data.h>

Public Member Functions
	Option_usage_data (const char *option_name, const mysql_service_registry_t *registry)
	Use this constructor at init time. More...
	Option_usage_data (Option_usage_data &)=delete
	~Option_usage_data ()
bool	set (bool is_used)
	Records usage. More...
bool	set_sampled (bool is_used, unsigned long log_usage_every_nth_time)
	Records usage (calls Option_usage_data::set()) every Nth call. More...

Protected Attributes
const char *	m_option_name
const mysql_service_registry_t *	m_registry
std::atomic< unsigned >	m_counter

Detailed Description

A helper class to handle option usage population.

Adds a top level JSON object (if missing), then adds (if missing, otherwise updates) the following two JSON elements to the top level JSON object: used (boolean) usedDate (ISO 8601 string)

Create an instance of the class at component/plugin init time and dispose of it at deinit time as follows:

...
#include "mysql/components/library_mysys/option_usage_data.h"
...
Option_usage_data *handlerton{nullptr};
...
init() {
  ...
  usage_data = new Option_usage_data("feature name",
SERVICE_PLACEHOLDER(registry)); if (!usage_data) return 1;
  ...
}
...
deinit() {
  ..
  delete usage_data;
  usage_data = nullptr;
  ..
}

Now, when the functionality is used (careful, an expensive call), do:

usage_data->set_sampled(true);

Do not register usage at the time the plugin component is initilized. Try to register it at the time it is actually being used. But do not do it too often: it parses JSON and writes to an InnoDB table!

Constructor & Destructor Documentation

Option_usage_data() [1/2]

Option_usage_data::Option_usage_data ( const char *  option_name, const mysql_service_registry_t *  registry  )

inline

Use this constructor at init time.

Parameters

option_name	The name of the option to register usage for
registry	a reference to the registry service

Option_usage_data() [2/2]

Option_usage_data::Option_usage_data ( Option_usage_data &  )

delete

~Option_usage_data()

Option_usage_data::~Option_usage_data ( )

inline

Member Function Documentation

set()

bool Option_usage_data::set

(

bool

is_used

)

Records usage.

Parameters

is_used

True if the feature is used.

Return values

true	Error
false	Success

set_sampled()

bool Option_usage_data::set_sampled	(	bool	is_used,
		unsigned long	log_usage_every_nth_time
	)

Records usage (calls Option_usage_data::set()) every Nth call.

Very useful for high volume of calls to the usage function.

Parameters

is_used	True if the feature is used.
log_usage_every_nth_time	Log usage for every Nth call to this function.

Return values

true	Error
false	Success

Member Data Documentation

m_counter

std::atomic<unsigned> Option_usage_data::m_counter

protected

m_option_name

const char* Option_usage_data::m_option_name

protected

m_registry

const mysql_service_registry_t* Option_usage_data::m_registry

protected

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

• include/mysql/components/library_mysys/option_usage_data.h
• components/library_mysys/option_usage_data.cc