VictoriaMetrics/app/vmalert/rule.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

119 lines
2.8 KiB
Go

package main
import (
"context"
"errors"
"sync"
"time"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
)
// Rule represents alerting or recording rule
// that has unique ID, can be Executed and
// updated with other Rule.
type Rule interface {
// ID returns unique ID that may be used for
// identifying this Rule among others.
ID() uint64
// Exec executes the rule with given context at the given timestamp and limit.
// returns an err if number of resulting time series exceeds the limit.
Exec(ctx context.Context, ts time.Time, limit int) ([]prompbmarshal.TimeSeries, error)
// ExecRange executes the rule on the given time range.
ExecRange(ctx context.Context, start, end time.Time) ([]prompbmarshal.TimeSeries, error)
// UpdateWith performs modification of current Rule
// with fields of the given Rule.
UpdateWith(Rule) error
// ToAPI converts Rule into APIRule
ToAPI() APIRule
// Close performs the shutdown procedures for rule
// such as metrics unregister
Close()
}
var errDuplicate = errors.New("result contains metrics with the same labelset after applying rule labels")
type ruleState struct {
sync.RWMutex
entries []ruleStateEntry
cur int
}
type ruleStateEntry struct {
// stores last moment of time rule.Exec was called
time time.Time
// stores the timesteamp with which rule.Exec was called
at time.Time
// stores the duration of the last rule.Exec call
duration time.Duration
// stores last error that happened in Exec func
// resets on every successful Exec
// may be used as Health ruleState
err error
// stores the number of samples returned during
// the last evaluation
samples int
// stores the number of time series fetched during
// the last evaluation.
// Is supported by VictoriaMetrics only, starting from v1.90.0
// If seriesFetched == nil, then this attribute was missing in
// datasource response (unsupported).
seriesFetched *int
// stores the curl command reflecting the HTTP request used during rule.Exec
curl string
}
func newRuleState(size int) *ruleState {
if size < 1 {
size = 1
}
return &ruleState{
entries: make([]ruleStateEntry, size),
}
}
func (s *ruleState) getLast() ruleStateEntry {
s.RLock()
defer s.RUnlock()
return s.entries[s.cur]
}
func (s *ruleState) size() int {
s.RLock()
defer s.RUnlock()
return len(s.entries)
}
func (s *ruleState) getAll() []ruleStateEntry {
entries := make([]ruleStateEntry, 0)
s.RLock()
defer s.RUnlock()
cur := s.cur
for {
e := s.entries[cur]
if !e.time.IsZero() || !e.at.IsZero() {
entries = append(entries, e)
}
cur--
if cur < 0 {
cur = cap(s.entries) - 1
}
if cur == s.cur {
return entries
}
}
}
func (s *ruleState) add(e ruleStateEntry) {
s.Lock()
defer s.Unlock()
s.cur++
if s.cur > cap(s.entries)-1 {
s.cur = 0
}
s.entries[s.cur] = e
}