VictoriaMetrics/app/vmalert/datasource/vm_graphite_api.go
Roman Khavronenko 5b8450fc1b
app/vmalert: detect alerting rules which don't match any series at all (#4198)
app/vmalert: detect alerting rules which don't match any series at all

vmalert starts to understand /query responses which contain object:
```
"stats":{"seriesFetched": "42"}
```
If object is present, vmalert parses it and populates a new field
`SeriesFetched`. This field is then used to populate the new metric
`vmalert_alerting_rules_last_evaluation_series_fetched` and to
display warnings in the vmalert's UI.

If response doesn't contain the new object (Prometheus or
VictoriaMetrics earlier than v1.90), then `SeriesFetched=nil`.
In this case, UI will contain no additional warnings.
And `vmalert_alerting_rules_last_evaluation_series_fetched` will
be set to `-1`. Negative value of the metric will help to compile
correct alerting rule in follow-up.

Thanks for the initial implementation to @Haleygo
See https://github.com/VictoriaMetrics/VictoriaMetrics/pull/4056

See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4039

Signed-off-by: hagen1778 <roman@victoriametrics.com>
2023-05-08 09:36:39 +02:00

75 lines
1.7 KiB
Go

package datasource
import (
"encoding/json"
"fmt"
"net/http"
"strconv"
"time"
)
type graphiteResponse []graphiteResponseTarget
type graphiteResponseTarget struct {
Target string `json:"target"`
Tags map[string]string `json:"tags"`
DataPoints [][2]float64 `json:"datapoints"`
}
func (r graphiteResponse) metrics() []Metric {
var ms []Metric
for _, res := range r {
if len(res.DataPoints) < 1 {
continue
}
var m Metric
// add only last value to the result.
last := res.DataPoints[len(res.DataPoints)-1]
m.Values = append(m.Values, last[0])
m.Timestamps = append(m.Timestamps, int64(last[1]))
for k, v := range res.Tags {
m.AddLabel(k, v)
}
ms = append(ms, m)
}
return ms
}
func parseGraphiteResponse(req *http.Request, resp *http.Response) (Result, error) {
r := &graphiteResponse{}
if err := json.NewDecoder(resp.Body).Decode(r); err != nil {
return Result{}, fmt.Errorf("error parsing graphite metrics for %s: %w", req.URL.Redacted(), err)
}
return Result{Data: r.metrics()}, nil
}
const (
graphitePath = "/render"
graphitePrefix = "/graphite"
)
func (s *VMStorage) setGraphiteReqParams(r *http.Request, query string, timestamp time.Time) {
if s.appendTypePrefix {
r.URL.Path += graphitePrefix
}
r.URL.Path += graphitePath
q := r.URL.Query()
for k, vs := range s.extraParams {
if q.Has(k) { // extraParams are prior to params in URL
q.Del(k)
}
for _, v := range vs {
q.Add(k, v)
}
}
q.Set("format", "json")
q.Set("target", query)
from := "-5min"
if s.lookBack > 0 {
lookBack := timestamp.Add(-s.lookBack)
from = strconv.FormatInt(lookBack.Unix(), 10)
}
q.Set("from", from)
q.Set("until", "now")
r.URL.RawQuery = q.Encode()
}