VictoriaMetrics/vendor/github.com/prometheus/common/model/metric.go
Aliaksandr Valialkin d5c180e680 app/vmctl: move vmctl code from github.com/VictoriaMetrics/vmctl
It is better developing vmctl tool in VictoriaMetrics repository, so it could be released
together with the rest of vmutils tools such as vmalert, vmagent, vmbackup, vmrestore and vmauth.
2021-02-01 01:10:20 +02:00

102 lines
2.8 KiB
Go

// Copyright 2013 The Prometheus Authors
// 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 model
import (
"fmt"
"regexp"
"sort"
"strings"
)
var (
// MetricNameRE is a regular expression matching valid metric
// names. Note that the IsValidMetricName function performs the same
// check but faster than a match with this regular expression.
MetricNameRE = regexp.MustCompile(`^[a-zA-Z_:][a-zA-Z0-9_:]*$`)
)
// A Metric is similar to a LabelSet, but the key difference is that a Metric is
// a singleton and refers to one and only one stream of samples.
type Metric LabelSet
// Equal compares the metrics.
func (m Metric) Equal(o Metric) bool {
return LabelSet(m).Equal(LabelSet(o))
}
// Before compares the metrics' underlying label sets.
func (m Metric) Before(o Metric) bool {
return LabelSet(m).Before(LabelSet(o))
}
// Clone returns a copy of the Metric.
func (m Metric) Clone() Metric {
clone := make(Metric, len(m))
for k, v := range m {
clone[k] = v
}
return clone
}
func (m Metric) String() string {
metricName, hasName := m[MetricNameLabel]
numLabels := len(m) - 1
if !hasName {
numLabels = len(m)
}
labelStrings := make([]string, 0, numLabels)
for label, value := range m {
if label != MetricNameLabel {
labelStrings = append(labelStrings, fmt.Sprintf("%s=%q", label, value))
}
}
switch numLabels {
case 0:
if hasName {
return string(metricName)
}
return "{}"
default:
sort.Strings(labelStrings)
return fmt.Sprintf("%s{%s}", metricName, strings.Join(labelStrings, ", "))
}
}
// Fingerprint returns a Metric's Fingerprint.
func (m Metric) Fingerprint() Fingerprint {
return LabelSet(m).Fingerprint()
}
// FastFingerprint returns a Metric's Fingerprint calculated by a faster hashing
// algorithm, which is, however, more susceptible to hash collisions.
func (m Metric) FastFingerprint() Fingerprint {
return LabelSet(m).FastFingerprint()
}
// IsValidMetricName returns true iff name matches the pattern of MetricNameRE.
// This function, however, does not use MetricNameRE for the check but a much
// faster hardcoded implementation.
func IsValidMetricName(n LabelValue) bool {
if len(n) == 0 {
return false
}
for i, b := range n {
if !((b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_' || b == ':' || (b >= '0' && b <= '9' && i > 0)) {
return false
}
}
return true
}