prometheus/rules/ast/persistence_adapter.go

107 lines
3.1 KiB
Go

// Copyright 2013 Prometheus Team
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package ast
import (
"flag"
"github.com/prometheus/prometheus/model"
"github.com/prometheus/prometheus/storage/metric"
"time"
)
var defaultStalenessDelta = flag.Int("defaultStalenessDelta", 300, "Default staleness delta allowance in seconds during expression evaluations.")
type PersistenceAdapter struct {
persistence metric.MetricPersistence
stalenessPolicy *metric.StalenessPolicy
}
// AST-global persistence to use.
var persistenceAdapter *PersistenceAdapter = nil
func (p *PersistenceAdapter) GetValueAtTime(labels model.LabelSet, timestamp *time.Time) (samples []*model.Sample, err error) {
fingerprints, err := p.persistence.GetFingerprintsForLabelSet(labels)
if err != nil {
return
}
for _, fingerprint := range fingerprints {
var sample *model.Sample // Don't shadow err.
sample, err = p.persistence.GetValueAtTime(fingerprint, *timestamp, *p.stalenessPolicy)
if err != nil {
return
}
if sample == nil {
continue
}
samples = append(samples, sample)
}
return
}
func (p *PersistenceAdapter) GetBoundaryValues(labels model.LabelSet, interval *model.Interval) (sampleSets []*model.SampleSet, err error) {
fingerprints, err := p.persistence.GetFingerprintsForLabelSet(labels)
if err != nil {
return
}
for _, fingerprint := range fingerprints {
var sampleSet *model.SampleSet // Don't shadow err.
// TODO: change to GetBoundaryValues() once it has the right return type.
sampleSet, err = p.persistence.GetRangeValues(fingerprint, *interval)
if err != nil {
return nil, err
}
if sampleSet == nil {
continue
}
sampleSets = append(sampleSets, sampleSet)
}
return sampleSets, nil
}
func (p *PersistenceAdapter) GetRangeValues(labels model.LabelSet, interval *model.Interval) (sampleSets []*model.SampleSet, err error) {
fingerprints, err := p.persistence.GetFingerprintsForLabelSet(labels)
if err != nil {
return
}
for _, fingerprint := range fingerprints {
var sampleSet *model.SampleSet // Don't shadow err.
sampleSet, err = p.persistence.GetRangeValues(fingerprint, *interval)
if err != nil {
return nil, err
}
if sampleSet == nil {
continue
}
sampleSets = append(sampleSets, sampleSet)
}
return sampleSets, nil
}
func SetPersistence(persistence metric.MetricPersistence, policy *metric.StalenessPolicy) {
if policy == nil {
policy = &metric.StalenessPolicy{
DeltaAllowance: time.Duration(*defaultStalenessDelta) * time.Second,
}
}
persistenceAdapter = &PersistenceAdapter{
persistence: persistence,
stalenessPolicy: policy,
}
}