Method Do

pkg/querier/tripperware/queryrange/limits.go:40–98

(ctx context.Context, r tripperware.Request)

}

func (l limitsMiddleware) Do(ctx context.Context, r tripperware.Request) (tripperware.Response, error) {
	log, ctx := spanlogger.New(ctx, "limits")
	defer log.Finish()

	tenantIDs, err := users.TenantIDs(ctx)
	if err != nil {
		return nil, httpgrpc.Errorf(http.StatusBadRequest, "%s", err.Error())
	}

	// Clamp the time range based on the max query lookback.

	if maxQueryLookback := validation.SmallestPositiveNonZeroDurationPerTenant(tenantIDs, l.MaxQueryLookback); maxQueryLookback > 0 {
		minStartTime := util.TimeToMillis(time.Now().Add(-maxQueryLookback))

		if r.GetEnd() < minStartTime {
			// The request is fully outside the allowed range, so we can return an
			// empty response.
			level.Debug(log).Log(
				"msg", "skipping the execution of the query because its time range is before the 'max query lookback' setting",
				"reqStart", util.FormatTimeMillis(r.GetStart()),
				"redEnd", util.FormatTimeMillis(r.GetEnd()),
				"maxQueryLookback", maxQueryLookback)

			return tripperware.NewEmptyPrometheusResponse(false), nil
		}

		if r.GetStart() < minStartTime {
			// Replace the start time in the request.
			level.Debug(log).Log(
				"msg", "the start time of the query has been manipulated because of the 'max query lookback' setting",
				"original", util.FormatTimeMillis(r.GetStart()),
				"updated", util.FormatTimeMillis(minStartTime))

			r = r.WithStartEnd(minStartTime, r.GetEnd())
		}
	}

	// Enforce the max query length.
	maxQueryLength := validation.SmallestPositiveNonZeroDurationPerTenant(tenantIDs, l.MaxQueryLength)
	if maxQueryLength > 0 {
		queryLen := timestamp.Time(r.GetEnd()).Sub(timestamp.Time(r.GetStart()))
		if queryLen > maxQueryLength {
			return nil, httpgrpc.Errorf(http.StatusBadRequest, validation.ErrQueryTooLong, queryLen, maxQueryLength)
		}

		expr, err := cortexparser.ParseExpr(r.GetQuery())
		if err != nil {
			return nil, httpgrpc.Errorf(http.StatusBadRequest, "%s", err.Error())
		}

		// Enforce query length across all selectors in the query.
		length := promql.FindNonOverlapQueryLength(expr, 0, 0, l.lookbackDelta)
		if length > maxQueryLength {
			return nil, httpgrpc.Errorf(http.StatusBadRequest, validation.ErrQueryTooLong, length, maxQueryLength)
		}
	}

	return l.next.Do(ctx, r)