Service for managing the list of loaded Components. More...

#include <persistent_dynamic_loader.h>

Public Attributes
mysql_service_status_t(*	load )(void thd, const char urns[], int component_count)
	Loads specified group of components by URN, initializes them and registers all service implementations present in these components. More...

mysql_service_status_t(*	unload )(void thd, const char urns[], int component_count)
	Unloads specified group of Components by URN, deinitializes them and unregisters all service implementations present in these components. More...

Detailed Description

Service for managing the list of loaded Components.

It assures the list to be persisted in MySQL table.

This service breaks a little a concept of having only simple types as arguments. This possibly could be improved further into process of making more system parts implemented as proper components. Once we have a way to access (system) tables through services, this would not be needed and persistent dynamic loader could be another implementation of dynamic_loader service. Also, the THD parameter could be replaced by getting the value of the current_thd.

Member Data Documentation

◆ load

mysql_service_status_t(* s_mysql_persistent_dynamic_loader::load) (void *thd, const char *urns[], int component_count)

Loads specified group of components by URN, initializes them and registers all service implementations present in these components.

Assures all dependencies will be met after loading specified components. The dependencies may be circular, in such case it's necessary to specify all components on cycle to load in one batch. From URNs specified the scheme part of URN (part before "://") is extracted and used to acquire service implementation of scheme component loader service for specified scheme. If the loading process successes then a group of Components by their URN is added to the component table.

Parameters

thd	Current thread execution context.
urns	List of URNs of Components to load.
component_count	Number of Components on list to load.

Returns: Status of performed operation

Return values

false	success
true	failure

◆ unload

mysql_service_status_t(* s_mysql_persistent_dynamic_loader::unload) (void *thd, const char *urns[], int component_count)

Unloads specified group of Components by URN, deinitializes them and unregisters all service implementations present in these components.

Assumes, although does not check it, all dependencies of not unloaded components will still be met after unloading specified components. The dependencies may be circular, in such case it's necessary to specify all components on cycle to unload in one batch. From URNs specified the scheme part of URN (part before "://") is extracted and used to acquire service implementation of scheme component loader service for specified scheme. If the unloading process successes then a group of Components by their URN is added to the component table.