grafana/pkg/tsdb/cloud-monitoring/time/interval.go

77 lines
2.0 KiB
Go

// Copied from https://github.com/grafana/grafana/blob/main/pkg/tsdb/intervalv2/intervalv2.go
// We're copying this to not block ourselves from decoupling until the conversation here is resolved
// https://raintank-corp.slack.com/archives/C05QFJUHUQ6/p1700064431005089
package time
import (
"time"
"github.com/grafana/grafana-plugin-sdk-go/backend"
"github.com/grafana/grafana-plugin-sdk-go/backend/gtime"
)
var (
DefaultRes int64 = 1500
defaultMinInterval = time.Millisecond * 1
)
type Interval struct {
Text string
Value time.Duration
}
type intervalCalculator struct {
minInterval time.Duration
}
type Calculator interface {
Calculate(timerange backend.TimeRange, minInterval time.Duration, maxDataPoints int64) Interval
CalculateSafeInterval(timerange backend.TimeRange, resolution int64) Interval
}
type CalculatorOptions struct {
MinInterval time.Duration
}
func NewCalculator(opts ...CalculatorOptions) *intervalCalculator {
calc := &intervalCalculator{}
for _, o := range opts {
if o.MinInterval == 0 {
calc.minInterval = defaultMinInterval
} else {
calc.minInterval = o.MinInterval
}
}
return calc
}
func (ic *intervalCalculator) Calculate(timerange backend.TimeRange, minInterval time.Duration, maxDataPoints int64) Interval {
to := timerange.To.UnixNano()
from := timerange.From.UnixNano()
resolution := maxDataPoints
if resolution == 0 {
resolution = DefaultRes
}
calculatedInterval := time.Duration((to - from) / resolution)
if calculatedInterval < minInterval {
return Interval{Text: gtime.FormatInterval(minInterval), Value: minInterval}
}
rounded := gtime.RoundInterval(calculatedInterval)
return Interval{Text: gtime.FormatInterval(rounded), Value: rounded}
}
func (ic *intervalCalculator) CalculateSafeInterval(timerange backend.TimeRange, safeRes int64) Interval {
to := timerange.To.UnixNano()
from := timerange.From.UnixNano()
safeInterval := time.Duration((to - from) / safeRes)
rounded := gtime.RoundInterval(safeInterval)
return Interval{Text: gtime.FormatInterval(rounded), Value: rounded}
}