prometheus/storage/metric/sample.go

150 lines
3.8 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 metric
import (
"bytes"
"fmt"
"sort"
clientmodel "github.com/prometheus/client_golang/model"
)
// MarshalJSON implements json.Marshaler.
func (s SamplePair) MarshalJSON() ([]byte, error) {
return []byte(fmt.Sprintf("{\"Value\": \"%f\", \"Timestamp\": %d}", s.Value, s.Timestamp)), nil
}
// SamplePair pairs a SampleValue with a Timestamp.
type SamplePair struct {
Timestamp clientmodel.Timestamp
Value clientmodel.SampleValue
}
// Equal returns true if this SamplePair and o have equal Values and equal
// Timestamps.
func (s *SamplePair) Equal(o *SamplePair) bool {
if s == o {
return true
}
return s.Value.Equal(o.Value) && s.Timestamp.Equal(o.Timestamp)
}
func (s *SamplePair) String() string {
return fmt.Sprintf("SamplePair at %s of %s", s.Timestamp, s.Value)
}
// Values is a sortable slice of SamplePairs (as in: it implements
// sort.Interface). Sorting happens by Timestamp.
type Values []SamplePair
// Len implements sort.Interface.
func (v Values) Len() int {
return len(v)
}
// Less implements sort.Interface.
func (v Values) Less(i, j int) bool {
return v[i].Timestamp.Before(v[j].Timestamp)
}
// Swap implements sort.Interface.
func (v Values) Swap(i, j int) {
v[i], v[j] = v[j], v[i]
}
// Equal returns true if these Values are of the same length as o, and each
// value is equal to the corresponding value in o (i.e. at the same index).
func (v Values) Equal(o Values) bool {
if len(v) != len(o) {
return false
}
for i, expected := range v {
if !expected.Equal(&o[i]) {
return false
}
}
return true
}
// FirstTimeAfter indicates whether the first sample of a set is after a given
// timestamp.
func (v Values) FirstTimeAfter(t clientmodel.Timestamp) 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 clientmodel.Timestamp) 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 clientmodel.Timestamp) bool {
switch {
case v.Len() == 0:
return false
case t.Before(v[0].Timestamp):
return false
case !v[v.Len()-1].Timestamp.Before(t):
return false
default:
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 clientmodel.Timestamp) Values {
index := sort.Search(len(v), func(i int) bool {
timestamp := v[i].Timestamp
return !timestamp.Before(t)
})
return v[index:]
}
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()
}
// SampleSet is Values with a Metric attached.
type SampleSet struct {
Metric clientmodel.Metric
Values Values
}
// Interval describes the inclusive interval between two Timestamps.
type Interval struct {
OldestInclusive clientmodel.Timestamp
NewestInclusive clientmodel.Timestamp
}