soa/service/stat_aggregator.h

/* graphite_connector.h                                            -*- C++ -*-
   Jeremy Barnes, 3 August 2011
   Copyright (c) 2011 Datacratic.  All rights reserved.

   Class to accumulate operational stats and connect to graphite (directly).
*/

#pragma once

#include "ace/SOCK_Dgram.h"
#include "jml/stats/distribution.h"
#include <boost/thread.hpp>
#include "soa/types/date.h"
#include <unordered_map>
#include <map>
#include <deque>
#include <boost/scoped_ptr.hpp>


namespace Datacratic {


struct StatReading {
    StatReading(const std::string & name = "",
                float value = 0.0,
                Date timestamp = Date())
        : name(name), value(value), timestamp(timestamp)
    {
    }

    std::string name;
    float value;
    Date timestamp;
};

/*****************************************************************************/
/* STAT AGGREGATOR                                                           */
/*****************************************************************************/

struct StatAggregator {

    virtual ~StatAggregator()
    {
    }

    virtual void record(float value) = 0;

    virtual std::vector<StatReading> read(const std::string & prefix) = 0;
};


/*****************************************************************************/
/* COUNTER AGGREGATOR                                                        */
/*****************************************************************************/

struct CounterAggregator : public StatAggregator {
    CounterAggregator();

    virtual ~CounterAggregator();

    virtual void record(float value);

    std::pair<double, Date> reset();

    virtual std::vector<StatReading> read(const std::string & prefix);

private:
    Date start;    //< Date at which we last cleared the counter
    double total;  //< total since we last added it up

    std::deque<double> totalsBuffer; //< Totals for the last n reads.

};


/*****************************************************************************/
/* GAUGE AGGREGATOR                                                          */
/*****************************************************************************/

struct GaugeAggregator : public StatAggregator {
    GaugeAggregator();

    virtual ~GaugeAggregator();

    virtual void record(float value);

    std::pair<ML::distribution<float> *, Date> reset();

    virtual std::vector<StatReading> read(const std::string & prefix);

private:
    Date start;  //< Date at which we last cleared the counter
    ML::distribution<float> * volatile values;  //< List of added values
};


} // namespace Datacratic