Example #1
0
// Query handles the /api/query endpoint.
func (serv MetricsService) Query(w http.ResponseWriter, r *http.Request) {
	setAccessControlHeaders(w)

	params := httputils.GetQueryParams(r)
	expr := params.Get("expr")
	asText := params.Get("asText")

	var format ast.OutputFormat
	// BUG(julius): Use Content-Type negotiation.
	if asText == "" {
		format = ast.JSON
		w.Header().Set("Content-Type", "application/json")
	} else {
		format = ast.Text
		w.Header().Set("Content-Type", "text/plain")
	}

	exprNode, err := rules.LoadExprFromString(expr)
	if err != nil {
		fmt.Fprint(w, ast.ErrorToJSON(err))
		return
	}

	timestamp := clientmodel.TimestampFromTime(serv.time.Now())

	queryStats := stats.NewTimerGroup()
	result := ast.EvalToString(exprNode, timestamp, format, serv.Storage, queryStats)
	glog.V(1).Infof("Instant query: %s\nQuery stats:\n%s\n", expr, queryStats)
	fmt.Fprint(w, result)
}
Example #2
0
// SetTargets handles the /api/targets endpoint.
func (serv MetricsService) SetTargets(w http.ResponseWriter, r *http.Request) {
	params := httputils.GetQueryParams(r)
	jobName := params.Get("job")

	decoder := json.NewDecoder(r.Body)
	var targetGroups []TargetGroup
	err := decoder.Decode(&targetGroups)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	job := serv.Config.GetJobByName(jobName)
	if job == nil {
		http.Error(w, "job not found", http.StatusNotFound)
		return
	}

	newTargets := []retrieval.Target{}

	for _, targetGroup := range targetGroups {
		// Do mandatory map type conversion due to Go shortcomings.
		baseLabels := clientmodel.LabelSet{
			clientmodel.JobLabel: clientmodel.LabelValue(job.GetName()),
		}
		for label, value := range targetGroup.BaseLabels {
			baseLabels[clientmodel.LabelName(label)] = clientmodel.LabelValue(value)
		}

		for _, endpoint := range targetGroup.Endpoints {
			newTarget := retrieval.NewTarget(endpoint, job.ScrapeTimeout(), baseLabels)
			newTargets = append(newTargets, newTarget)
		}
	}

	// BUG(julius): Validate that this ScrapeInterval is in fact the proper one
	// for the job.
	serv.TargetManager.ReplaceTargets(*job, newTargets)
}
Example #3
0
// QueryRange handles the /api/query_range endpoint.
func (serv MetricsService) QueryRange(w http.ResponseWriter, r *http.Request) {
	setAccessControlHeaders(w)
	w.Header().Set("Content-Type", "application/json")

	params := httputils.GetQueryParams(r)
	expr := params.Get("expr")

	// Input times and durations are in seconds and get converted to nanoseconds.
	endFloat, _ := strconv.ParseFloat(params.Get("end"), 64)
	durationFloat, _ := strconv.ParseFloat(params.Get("range"), 64)
	stepFloat, _ := strconv.ParseFloat(params.Get("step"), 64)
	nanosPerSecond := int64(time.Second / time.Nanosecond)
	end := int64(endFloat) * nanosPerSecond
	duration := int64(durationFloat) * nanosPerSecond
	step := int64(stepFloat) * nanosPerSecond

	exprNode, err := rules.LoadExprFromString(expr)
	if err != nil {
		fmt.Fprint(w, ast.ErrorToJSON(err))
		return
	}
	if exprNode.Type() != ast.VectorType {
		fmt.Fprint(w, ast.ErrorToJSON(errors.New("expression does not evaluate to vector type")))
		return
	}

	if end == 0 {
		end = clientmodel.Now().UnixNano()
	}

	if step <= 0 {
		step = nanosPerSecond
	}

	if end-duration < 0 {
		duration = end
	}

	// For safety, limit the number of returned points per timeseries.
	// This is sufficient for 60s resolution for a week or 1h resolution for a year.
	if duration/step > 11000 {
		fmt.Fprint(w, ast.ErrorToJSON(errors.New("exceeded maximum resolution of 11,000 points per timeseries. Try decreasing the query resolution (?step=XX)")))
		return
	}

	// Align the start to step "tick" boundary.
	end -= end % step

	queryStats := stats.NewTimerGroup()

	evalTimer := queryStats.GetTimer(stats.TotalEvalTime).Start()
	matrix, err := ast.EvalVectorRange(
		exprNode.(ast.VectorNode),
		clientmodel.TimestampFromUnixNano(end-duration),
		clientmodel.TimestampFromUnixNano(end),
		time.Duration(step),
		serv.Storage,
		queryStats)
	if err != nil {
		fmt.Fprint(w, ast.ErrorToJSON(err))
		return
	}
	evalTimer.Stop()

	sortTimer := queryStats.GetTimer(stats.ResultSortTime).Start()
	sort.Sort(matrix)
	sortTimer.Stop()

	jsonTimer := queryStats.GetTimer(stats.JSONEncodeTime).Start()
	result := ast.TypedValueToJSON(matrix, "matrix")
	jsonTimer.Stop()

	glog.V(1).Infof("Range query: %s\nQuery stats:\n%s\n", expr, queryStats)
	fmt.Fprint(w, result)
}