VictoriaMetrics/app/vmalert/datasource/vm_graphite_api.go
Roman Khavronenko 5aa7846900 vmalert: support rules backfilling (aka replay) (#1358)
* vmalert: support rules backfilling (aka `replay`)

vmalert can `replay` configured rules in the past
and backfill results via remote write protocol.
It supports MetricsQL/PromQL storage as data source,
and can backfill data to remote write compatible
storage.

Supports recording and alerting rules `replay`. See more
details in README.

https://github.com/VictoriaMetrics/VictoriaMetrics/issues/836

* vmalert: review fixes

* vmalert: readme fixes
2021-06-09 12:30:54 +03:00

67 lines
1.5 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) ([]Metric, error) {
r := &graphiteResponse{}
if err := json.NewDecoder(resp.Body).Decode(r); err != nil {
return nil, fmt.Errorf("error parsing graphite metrics for %s: %w", req.URL, err)
}
return 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()
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()
}