Method Select

pkg/querier/querier.go:386–483

Select implements storage.Querier interface. The bool passed is ignored because the series is always sorted.

(ctx context.Context, sortSeries bool, sp *storage.SelectHints, matchers ...*labels.Matcher)

// Select implements storage.Querier interface.
// The bool passed is ignored because the series is always sorted.
func (q querier) Select(ctx context.Context, sortSeries bool, sp *storage.SelectHints, matchers ...*labels.Matcher) storage.SeriesSet {
	ctx, stats, userID, mint, maxt, metadataQuerier, queriers, err := q.setupFromCtx(ctx)
	if err == errEmptyTimeRange {
		return storage.EmptySeriesSet()
	} else if err != nil {
		return storage.ErrSeriesSet(err)
	}
	startT := time.Now()
	defer func() {
		stats.AddQueryStorageWallTime(time.Since(startT))
	}()

	log, ctx := spanlogger.New(ctx, "querier.Select")
	defer log.Finish()

	if sp != nil {
		level.Debug(log).Log("start", util.TimeFromMillis(sp.Start).UTC().String(), "end", util.TimeFromMillis(sp.End).UTC().String(), "step", sp.Step, "matchers", matchers)
	}

	if sp == nil {
		mint, maxt, err = validateQueryTimeRange(ctx, userID, mint, maxt, q.limits, q.maxQueryIntoFuture)
		if err == errEmptyTimeRange {
			return storage.EmptySeriesSet()
		} else if err != nil {
			return storage.ErrSeriesSet(err)
		}
		// if SelectHints is null, rely on minT, maxT of querier to scope in range for Select stmt
		sp = &storage.SelectHints{Start: mint, End: maxt}
	}

	// Validate query time range. Even if the time range has already been validated when we created
	// the querier, we need to check it again here because the time range specified in hints may be
	// different.
	startMs, endMs, err := validateQueryTimeRange(ctx, userID, sp.Start, sp.End, q.limits, q.maxQueryIntoFuture)
	if err == errEmptyTimeRange {
		return storage.NoopSeriesSet()
	} else if err != nil {
		return storage.ErrSeriesSet(err)
	}

	// The time range may have been manipulated during the validation,
	// so we make sure changes are reflected back to hints.
	sp.Start = startMs
	sp.End = endMs
	getSeries := sp.Func == "series"

	// For series queries without specifying the start time, we prefer to
	// only query ingesters and not to query maxQueryLength to avoid OOM kill.
	if getSeries && startMs == 0 {
		return metadataQuerier.Select(ctx, true, sp, matchers...)
	}

	startTime := model.Time(startMs)
	endTime := model.Time(endMs)

	// Validate query time range. This validation for instant / range queries can be done either at Query Frontend
	// or here at Querier. When the check is done at Query Frontend, we still want to enforce the max query length
	// check for /api/v1/series request since there is no specific tripperware for series.