implement missing value fill functionality for postgres

This commit is contained in:
Sven Klemm 2017-12-10 11:42:55 +01:00
parent e2a3590d8b
commit c1282e8ea8

View File

@ -4,6 +4,7 @@ import (
"container/list"
"context"
"fmt"
"math"
"net/url"
"strconv"
"time"
@ -198,6 +199,18 @@ func (e PostgresQueryEndpoint) transformToTimeSeries(query *tsdb.Query, rows *co
return fmt.Errorf("Found no column named time")
}
fillMissing := query.Model.Get("fill").MustBool(false)
var fillInterval float64
fillValue := null.Float{}
if fillMissing {
fillInterval = query.Model.Get("fillInterval").MustFloat64() * 1000
if query.Model.Get("fillNULL").MustBool(false) == false {
fillValue.Float64 = query.Model.Get("fillValue").MustFloat64()
fillValue.Valid = true
}
}
for rows.Next() {
var timestamp float64
var value null.Float
@ -249,7 +262,34 @@ func (e PostgresQueryEndpoint) transformToTimeSeries(query *tsdb.Query, rows *co
if metricIndex == -1 {
metric = col
}
e.appendTimePoint(pointsBySeries, seriesByQueryOrder, metric, timestamp, value)
series, exist := pointsBySeries[metric]
if exist == false {
series = &tsdb.TimeSeries{Name: metric}
pointsBySeries[metric] = series
seriesByQueryOrder.PushBack(metric)
}
if fillMissing {
var intervalStart float64
if exist == false {
intervalStart = float64(tsdbQuery.TimeRange.MustGetFrom().UnixNano() / 1e6)
} else {
intervalStart = series.Points[len(series.Points)-1][1].Float64 + fillInterval
}
// align interval start
intervalStart = math.Floor(intervalStart/fillInterval) * fillInterval
for i := intervalStart; i < timestamp; i += fillInterval {
series.Points = append(series.Points, tsdb.TimePoint{fillValue, null.FloatFrom(i)})
rowCount++
}
}
series.Points = append(series.Points, tsdb.TimePoint{value, null.FloatFrom(timestamp)})
e.log.Debug("Rows", "metric", metric, "time", timestamp, "value", value)
rowCount++
}
@ -258,20 +298,22 @@ func (e PostgresQueryEndpoint) transformToTimeSeries(query *tsdb.Query, rows *co
for elem := seriesByQueryOrder.Front(); elem != nil; elem = elem.Next() {
key := elem.Value.(string)
result.Series = append(result.Series, pointsBySeries[key])
if fillMissing {
series := pointsBySeries[key]
// fill in values from last fetched value till interval end
intervalStart := series.Points[len(series.Points)-1][1].Float64
intervalEnd := float64(tsdbQuery.TimeRange.MustGetTo().UnixNano() / 1e6)
// align interval start
intervalStart = math.Floor(intervalStart/fillInterval) * fillInterval
for i := intervalStart + fillInterval; i < intervalEnd; i += fillInterval {
series.Points = append(series.Points, tsdb.TimePoint{fillValue, null.FloatFrom(i)})
rowCount++
}
}
}
result.Meta.Set("rowCount", rowCount)
return nil
}
func (e PostgresQueryEndpoint) appendTimePoint(pointsBySeries map[string]*tsdb.TimeSeries, seriesByQueryOrder *list.List, metric string, timestamp float64, value null.Float) {
if series, exist := pointsBySeries[metric]; exist {
series.Points = append(series.Points, tsdb.TimePoint{value, null.FloatFrom(timestamp)})
} else {
series := &tsdb.TimeSeries{Name: metric}
series.Points = append(series.Points, tsdb.TimePoint{value, null.FloatFrom(timestamp)})
pointsBySeries[metric] = series
seriesByQueryOrder.PushBack(metric)
}
e.log.Debug("Rows", "metric", metric, "time", timestamp, "value", value)
}