prometheus/model/metric.go

254 lines
5.5 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 model
import (
"bytes"
"code.google.com/p/goprotobuf/proto"
"fmt"
dto "github.com/prometheus/prometheus/model/generated"
"sort"
"time"
)
const (
// XXX: Re-evaluate down the road.
reservedDelimiter = `"`
)
// A LabelSet is a collection of LabelName and LabelValue pairs. The LabelSet
// may be fully-qualified down to the point where it may resolve to a single
// Metric in the data store or not. All operations that occur within the realm
// of a LabelSet can emit a vector of Metric entities to which the LabelSet may
// match.
type LabelSet map[LabelName]LabelValue
// Helper function to non-destructively merge two label sets.
func (l LabelSet) Merge(other LabelSet) LabelSet {
result := make(LabelSet, len(l))
for k, v := range l {
result[k] = v
}
for k, v := range other {
result[k] = v
}
return result
}
func (l LabelSet) String() string {
var (
buffer bytes.Buffer
labels LabelNames
labelCount int = len(l)
)
for name := range l {
labels = append(labels, name)
}
sort.Sort(labels)
fmt.Fprintf(&buffer, "{")
for i := 0; i < labelCount; i++ {
var (
label = labels[i]
value = l[label]
)
switch i {
case labelCount - 1:
fmt.Fprintf(&buffer, "%s=%s", label, value)
default:
fmt.Fprintf(&buffer, "%s=%s, ", label, value)
}
}
fmt.Fprintf(&buffer, "}")
return buffer.String()
}
func (l LabelSet) ToMetric() (metric Metric) {
metric = Metric{}
for label, value := range l {
metric[label] = value
}
return
}
// 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 map[LabelName]LabelValue
// A SampleValue is a representation of a value for a given sample at a given
// time.
type SampleValue float64
func (s SampleValue) Equal(o SampleValue) bool {
return s == o
}
func (s SampleValue) ToDTO() *float64 {
return proto.Float64(float64(s))
}
func (v SampleValue) MarshalJSON() ([]byte, error) {
return []byte(fmt.Sprintf(`"%f"`, v)), nil
}
func (v SampleValue) String() string {
return fmt.Sprint(float64(v))
}
func (s SamplePair) MarshalJSON() ([]byte, error) {
return []byte(fmt.Sprintf("{\"Value\": \"%f\", \"Timestamp\": %d}", s.Value, s.Timestamp.Unix())), nil
}
type SamplePair struct {
Value SampleValue
Timestamp time.Time
}
func (s SamplePair) Equal(o SamplePair) bool {
return s.Value.Equal(o.Value) && s.Timestamp.Equal(o.Timestamp)
}
func (s SamplePair) ToDTO() (out *dto.SampleValueSeries_Value) {
out = &dto.SampleValueSeries_Value{
Timestamp: proto.Int64(s.Timestamp.Unix()),
Value: s.Value.ToDTO(),
}
return
}
func (s SamplePair) String() string {
return fmt.Sprintf("SamplePair at %s of %s", s.Timestamp, s.Value)
}
type Values []SamplePair
func (v Values) Len() int {
return len(v)
}
func (v Values) Less(i, j int) bool {
return v[i].Timestamp.Before(v[j].Timestamp)
}
func (v Values) Swap(i, j int) {
v[i], v[j] = v[j], v[i]
}
// FirstTimeAfter indicates whether the first sample of a set is after a given
// timestamp.
func (v Values) FirstTimeAfter(t time.Time) bool {
return v[0].Timestamp.After(t)
}
// LastTimeBefore indicates whether the last sample of a set is before a given
// timestamp.
func (v Values) LastTimeBefore(t time.Time) bool {
return v[len(v)-1].Timestamp.Before(t)
}
// InsideInterval indicates whether a given range of sorted values could contain
// a value for a given time.
func (v Values) InsideInterval(t time.Time) (s bool) {
if v.Len() == 0 {
return
}
if t.Before(v[0].Timestamp) {
return
}
if !v[v.Len()-1].Timestamp.Before(t) {
return
}
return true
}
// TruncateBefore returns a subslice of the original such that extraneous
// samples in the collection that occur before the provided time are
// dropped. The original slice is not mutated
func (v Values) TruncateBefore(t time.Time) Values {
index := sort.Search(len(v), func(i int) bool {
timestamp := v[i].Timestamp
return !timestamp.Before(t)
})
return v[index:]
}
func (v Values) ToDTO() (out *dto.SampleValueSeries) {
out = &dto.SampleValueSeries{}
for _, value := range v {
out.Value = append(out.Value, value.ToDTO())
}
return
}
func (v Values) ToSampleKey(f Fingerprint) SampleKey {
return SampleKey{
Fingerprint: f,
FirstTimestamp: v[0].Timestamp,
LastTimestamp: v[len(v)-1].Timestamp,
SampleCount: uint32(len(v)),
}
}
func (v Values) String() string {
buffer := bytes.Buffer{}
fmt.Fprintf(&buffer, "[")
for i, value := range v {
fmt.Fprintf(&buffer, "%d. %s", i, value)
if i != len(v)-1 {
fmt.Fprintf(&buffer, "\n")
}
}
fmt.Fprintf(&buffer, "]")
return buffer.String()
}
func NewValuesFromDTO(dto *dto.SampleValueSeries) (v Values) {
for _, value := range dto.Value {
v = append(v, SamplePair{
Timestamp: time.Unix(*value.Timestamp, 0).UTC(),
Value: SampleValue(*value.Value),
})
}
return
}
type SampleSet struct {
Metric Metric
Values Values
}
type Interval struct {
OldestInclusive time.Time
NewestInclusive time.Time
}