Files
MaxScale/include/maxscale/monitor.hh
Johan Wikman 8ab247b237 MXS-1848 Introduce maxscape::MonitorApi
The purpose of this template class is to provide the
implementation of the monitor C-api. It's to be instantiated
with the class that actually provides the monitor behaviour.

A separate class maxscale::MonitorInstance will be provided
that then in turn implements the behaviour common to most
monitors. So, the structure will be like:

    class SomeMonitor : public maxscale::MonitorInstance {...}

    extern "C" MXS_MODULE* MXS_CREATE_MODULE()
    {
        static MXS_MODULE info =
        {
            ...
            &maxscale::MonitorApi<SomeMonitor>::s_api,
            ...
        };

        return &info;
    }
2018-05-07 14:48:35 +03:00

86 lines
2.5 KiB
C++

#pragma once
/*
* Copyright (c) 2016 MariaDB Corporation Ab
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file and at www.mariadb.com/bsl11.
*
* Change Date: 2020-01-01
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2 or later of the General
* Public License.
*/
#include <maxscale/cppdefs.hh>
#include <maxscale/monitor.h>
namespace maxscale
{
/**
* The purpose of the template MonitorApi is to provide an implementation
* of the monitor C-API. The template is instantiated with a class that
* provides the actual behaviour of a monitor.
*/
template<class MonitorInstance>
class MonitorApi
{
public:
MonitorApi() = delete;
MonitorApi(const MonitorApi&) = delete;
MonitorApi& operator = (const MonitorApi&) = delete;
static MXS_MONITOR_INSTANCE* createInstance(MXS_MONITOR* pMonitor)
{
MonitorInstance* pInstance = NULL;
MXS_EXCEPTION_GUARD(pInstance = MonitorInstance::create(pMonitor));
return pInstance;
}
static void destroyInstance(MXS_MONITOR_INSTANCE* pInstance)
{
MXS_EXCEPTION_GUARD(MonitorInstance::destroy(static_cast<MonitorInstance*>(pInstance)));
}
static bool startMonitor(MXS_MONITOR_INSTANCE* pInstance,
const MXS_CONFIG_PARAMETER* pParams)
{
bool started = false;
MXS_EXCEPTION_GUARD(started = static_cast<MonitorInstance*>(pInstance)->start(pParams));
return started;
}
static void stopMonitor(MXS_MONITOR_INSTANCE* pInstance)
{
MXS_EXCEPTION_GUARD(static_cast<MonitorInstance*>(pInstance)->stop());
}
static void diagnostics(const MXS_MONITOR_INSTANCE* pInstance, DCB* pDcb)
{
MXS_EXCEPTION_GUARD(static_cast<const MonitorInstance*>(pInstance)->diagnostics(pDcb));
}
static json_t* diagnostics_json(const MXS_MONITOR_INSTANCE* pInstance)
{
json_t* pJson = NULL;
MXS_EXCEPTION_GUARD(pJson = static_cast<const MonitorInstance*>(pInstance)->diagnostics_json());
return pJson;
}
static MXS_MONITOR_API s_api;
};
template<class MonitorInstance>
MXS_MONITOR_API MonitorApi<MonitorInstance>::s_api =
{
&MonitorApi<MonitorInstance>::createInstance,
&MonitorApi<MonitorInstance>::destroyInstance,
&MonitorApi<MonitorInstance>::startMonitor,
&MonitorApi<MonitorInstance>::stopMonitor,
&MonitorApi<MonitorInstance>::diagnostics,
&MonitorApi<MonitorInstance>::diagnostics_json,
};
}