grafana/pkg/tsdb/loki/parse_query.go
2022-03-01 14:46:52 -08:00

113 lines
3.1 KiB
Go

package loki
import (
"fmt"
"math"
"strconv"
"strings"
"time"
"github.com/grafana/grafana-plugin-sdk-go/backend"
"github.com/grafana/grafana/pkg/tsdb/intervalv2"
)
const (
varInterval = "$__interval"
varIntervalMs = "$__interval_ms"
varRange = "$__range"
varRangeS = "$__range_s"
varRangeMs = "$__range_ms"
)
const (
varIntervalAlt = "${__interval}"
varIntervalMsAlt = "${__interval_ms}"
varRangeAlt = "${__range}"
varRangeSAlt = "${__range_s}"
varRangeMsAlt = "${__range_ms}"
)
func interpolateVariables(expr string, interval time.Duration, timeRange time.Duration) string {
intervalText := intervalv2.FormatDuration(interval)
intervalMsText := strconv.FormatInt(int64(interval/time.Millisecond), 10)
rangeMs := timeRange.Milliseconds()
rangeSRounded := int64(math.Round(float64(rangeMs) / 1000.0))
rangeMsText := strconv.FormatInt(rangeMs, 10)
rangeSText := strconv.FormatInt(rangeSRounded, 10)
expr = strings.ReplaceAll(expr, varIntervalMs, intervalMsText)
expr = strings.ReplaceAll(expr, varInterval, intervalText)
expr = strings.ReplaceAll(expr, varRangeMs, rangeMsText)
expr = strings.ReplaceAll(expr, varRangeS, rangeSText)
expr = strings.ReplaceAll(expr, varRange, rangeSText+"s")
// this is duplicated code, hopefully this can be handled in a nicer way when
// https://github.com/grafana/grafana/issues/42928 is done.
expr = strings.ReplaceAll(expr, varIntervalMsAlt, intervalMsText)
expr = strings.ReplaceAll(expr, varIntervalAlt, intervalText)
expr = strings.ReplaceAll(expr, varRangeMsAlt, rangeMsText)
expr = strings.ReplaceAll(expr, varRangeSAlt, rangeSText)
expr = strings.ReplaceAll(expr, varRangeAlt, rangeSText+"s")
return expr
}
func parseQueryType(jsonValue string) (QueryType, error) {
switch jsonValue {
case "instant":
return QueryTypeInstant, nil
case "range":
return QueryTypeRange, nil
case "":
// there are older queries stored in alerting that did not have queryType,
// those were range-queries
return QueryTypeRange, nil
default:
return QueryTypeRange, fmt.Errorf("invalid queryType: %s", jsonValue)
}
}
func parseQuery(queryContext *backend.QueryDataRequest) ([]*lokiQuery, error) {
qs := []*lokiQuery{}
for _, query := range queryContext.Queries {
model, err := parseQueryModel(query.JSON)
if err != nil {
return nil, err
}
start := query.TimeRange.From
end := query.TimeRange.To
var resolution int64 = 1
if model.Resolution >= 1 && model.Resolution <= 5 || model.Resolution == 10 {
resolution = model.Resolution
}
interval := query.Interval
timeRange := query.TimeRange.To.Sub(query.TimeRange.From)
step := calculateStep(interval, timeRange, resolution)
expr := interpolateVariables(model.Expr, interval, timeRange)
queryType, err := parseQueryType(model.QueryType)
if err != nil {
return nil, err
}
qs = append(qs, &lokiQuery{
Expr: expr,
QueryType: queryType,
Step: step,
MaxLines: model.MaxLines,
LegendFormat: model.LegendFormat,
Start: start,
End: end,
RefID: query.RefID,
VolumeQuery: model.VolumeQuery,
})
}
return qs, nil
}