mirror of https://github.com/prometheus/prometheus
labels: extract common code between slice and stringlabels
This reduces bulk and should avoid issues if a fix is made in one file and not the other. A few methods now call `Range()` instead of `range`, but nothing performance-sensitive. Signed-off-by: Bryan Boreham <bjboreham@gmail.com>pull/13159/head
Bryan Boreham
parent
f997c72f29
commit
a3e02f35d6
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@ -17,32 +17,12 @@ package labels
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import (
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"bytes"
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"encoding/json"
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"strconv"
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"strings"
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"github.com/cespare/xxhash/v2"
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"github.com/prometheus/common/model"
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"golang.org/x/exp/slices"
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)
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// Well-known label names used by Prometheus components.
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const (
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MetricName = "__name__"
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AlertName = "alertname"
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BucketLabel = "le"
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InstanceName = "instance"
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labelSep = '\xfe'
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)
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var seps = []byte{'\xff'}
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// Label is a key/value pair of strings.
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type Label struct {
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Name, Value string
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}
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// Labels is a sorted set of labels. Order has to be guaranteed upon
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// instantiation.
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type Labels []Label
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@ -51,23 +31,6 @@ func (ls Labels) Len() int { return len(ls) }
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func (ls Labels) Swap(i, j int) { ls[i], ls[j] = ls[j], ls[i] }
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func (ls Labels) Less(i, j int) bool { return ls[i].Name < ls[j].Name }
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func (ls Labels) String() string {
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var b bytes.Buffer
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b.WriteByte('{')
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for i, l := range ls {
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if i > 0 {
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b.WriteByte(',')
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b.WriteByte(' ')
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}
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b.WriteString(l.Name)
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b.WriteByte('=')
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b.WriteString(strconv.Quote(l.Value))
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}
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b.WriteByte('}')
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return b.String()
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}
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// Bytes returns ls as a byte slice.
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// It uses an byte invalid character as a separator and so should not be used for printing.
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func (ls Labels) Bytes(buf []byte) []byte {
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@ -84,40 +47,6 @@ func (ls Labels) Bytes(buf []byte) []byte {
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return b.Bytes()
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}
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// MarshalJSON implements json.Marshaler.
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func (ls Labels) MarshalJSON() ([]byte, error) {
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return json.Marshal(ls.Map())
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}
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// UnmarshalJSON implements json.Unmarshaler.
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func (ls *Labels) UnmarshalJSON(b []byte) error {
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var m map[string]string
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if err := json.Unmarshal(b, &m); err != nil {
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return err
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}
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*ls = FromMap(m)
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return nil
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}
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// MarshalYAML implements yaml.Marshaler.
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func (ls Labels) MarshalYAML() (interface{}, error) {
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return ls.Map(), nil
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}
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// UnmarshalYAML implements yaml.Unmarshaler.
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func (ls *Labels) UnmarshalYAML(unmarshal func(interface{}) error) error {
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var m map[string]string
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if err := unmarshal(&m); err != nil {
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return err
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}
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*ls = FromMap(m)
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return nil
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}
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// MatchLabels returns a subset of Labels that matches/does not match with the provided label names based on the 'on' boolean.
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// If on is set to true, it returns the subset of labels that match with the provided label names and its inverse when 'on' is set to false.
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func (ls Labels) MatchLabels(on bool, names ...string) Labels {
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@ -318,19 +247,6 @@ func (ls Labels) WithoutEmpty() Labels {
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return ls
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}
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// IsValid checks if the metric name or label names are valid.
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func (ls Labels) IsValid() bool {
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for _, l := range ls {
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if l.Name == model.MetricNameLabel && !model.IsValidMetricName(model.LabelValue(l.Value)) {
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return false
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}
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if !model.LabelName(l.Name).IsValid() || !model.LabelValue(l.Value).IsValid() {
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return false
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}
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}
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return true
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}
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// Equal returns whether the two label sets are equal.
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func Equal(ls, o Labels) bool {
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if len(ls) != len(o) {
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@ -344,15 +260,6 @@ func Equal(ls, o Labels) bool {
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return true
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}
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// Map returns a string map of the labels.
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func (ls Labels) Map() map[string]string {
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m := make(map[string]string, len(ls))
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for _, l := range ls {
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m[l.Name] = l.Value
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}
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return m
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}
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// EmptyLabels returns n empty Labels value, for convenience.
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func EmptyLabels() Labels {
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return Labels{}
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@ -368,15 +275,6 @@ func New(ls ...Label) Labels {
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return set
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}
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// FromMap returns new sorted Labels from the given map.
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func FromMap(m map[string]string) Labels {
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l := make([]Label, 0, len(m))
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for k, v := range m {
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l = append(l, Label{Name: k, Value: v})
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}
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return New(l...)
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}
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// FromStrings creates new labels from pairs of strings.
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func FromStrings(ss ...string) Labels {
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if len(ss)%2 != 0 {
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@ -460,118 +358,6 @@ func (ls Labels) ReleaseStrings(release func(string)) {
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}
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}
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// Builder allows modifying Labels.
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type Builder struct {
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base Labels
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del []string
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add []Label
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}
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// NewBuilder returns a new LabelsBuilder.
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func NewBuilder(base Labels) *Builder {
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b := &Builder{
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del: make([]string, 0, 5),
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add: make([]Label, 0, 5),
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}
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b.Reset(base)
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return b
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}
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// Reset clears all current state for the builder.
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func (b *Builder) Reset(base Labels) {
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b.base = base
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b.del = b.del[:0]
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b.add = b.add[:0]
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for _, l := range b.base {
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if l.Value == "" {
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b.del = append(b.del, l.Name)
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}
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}
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}
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// Del deletes the label of the given name.
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func (b *Builder) Del(ns ...string) *Builder {
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for _, n := range ns {
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for i, a := range b.add {
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if a.Name == n {
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b.add = append(b.add[:i], b.add[i+1:]...)
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}
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}
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b.del = append(b.del, n)
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}
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return b
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}
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// Keep removes all labels from the base except those with the given names.
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func (b *Builder) Keep(ns ...string) *Builder {
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Outer:
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for _, l := range b.base {
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for _, n := range ns {
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if l.Name == n {
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continue Outer
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}
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}
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b.del = append(b.del, l.Name)
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}
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return b
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}
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// Set the name/value pair as a label. A value of "" means delete that label.
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func (b *Builder) Set(n, v string) *Builder {
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if v == "" {
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// Empty labels are the same as missing labels.
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return b.Del(n)
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}
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for i, a := range b.add {
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if a.Name == n {
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b.add[i].Value = v
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return b
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}
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}
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b.add = append(b.add, Label{Name: n, Value: v})
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return b
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}
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func (b *Builder) Get(n string) string {
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// Del() removes entries from .add but Set() does not remove from .del, so check .add first.
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for _, a := range b.add {
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if a.Name == n {
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return a.Value
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}
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}
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if slices.Contains(b.del, n) {
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return ""
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}
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return b.base.Get(n)
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}
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// Range calls f on each label in the Builder.
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func (b *Builder) Range(f func(l Label)) {
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// Stack-based arrays to avoid heap allocation in most cases.
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var addStack [128]Label
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var delStack [128]string
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// Take a copy of add and del, so they are unaffected by calls to Set() or Del().
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origAdd, origDel := append(addStack[:0], b.add...), append(delStack[:0], b.del...)
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b.base.Range(func(l Label) {
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if !slices.Contains(origDel, l.Name) && !contains(origAdd, l.Name) {
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f(l)
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}
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})
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for _, a := range origAdd {
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f(a)
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}
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}
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func contains(s []Label, n string) bool {
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for _, a := range s {
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if a.Name == n {
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return true
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}
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}
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return false
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}
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// Labels returns the labels from the builder.
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// If no modifications were made, the original labels are returned.
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func (b *Builder) Labels() Labels {
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@ -0,0 +1,235 @@
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// Copyright 2017 The Prometheus Authors
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package labels
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import (
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"bytes"
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"encoding/json"
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"strconv"
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"github.com/prometheus/common/model"
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"golang.org/x/exp/slices"
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)
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const (
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MetricName = "__name__"
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AlertName = "alertname"
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BucketLabel = "le"
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InstanceName = "instance"
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labelSep = '\xfe'
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)
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var seps = []byte{'\xff'}
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// Label is a key/value pair of strings.
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type Label struct {
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Name, Value string
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}
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func (ls Labels) String() string {
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var b bytes.Buffer
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b.WriteByte('{')
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i := 0
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ls.Range(func(l Label) {
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if i > 0 {
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b.WriteByte(',')
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b.WriteByte(' ')
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}
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b.WriteString(l.Name)
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b.WriteByte('=')
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b.WriteString(strconv.Quote(l.Value))
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i++
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})
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b.WriteByte('}')
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return b.String()
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}
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// MarshalJSON implements json.Marshaler.
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func (ls Labels) MarshalJSON() ([]byte, error) {
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return json.Marshal(ls.Map())
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}
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// UnmarshalJSON implements json.Unmarshaler.
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func (ls *Labels) UnmarshalJSON(b []byte) error {
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var m map[string]string
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if err := json.Unmarshal(b, &m); err != nil {
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return err
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}
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*ls = FromMap(m)
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return nil
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}
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// MarshalYAML implements yaml.Marshaler.
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func (ls Labels) MarshalYAML() (interface{}, error) {
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return ls.Map(), nil
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}
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// UnmarshalYAML implements yaml.Unmarshaler.
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func (ls *Labels) UnmarshalYAML(unmarshal func(interface{}) error) error {
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var m map[string]string
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if err := unmarshal(&m); err != nil {
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return err
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}
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*ls = FromMap(m)
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return nil
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}
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// IsValid checks if the metric name or label names are valid.
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func (ls Labels) IsValid() bool {
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err := ls.Validate(func(l Label) error {
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if l.Name == model.MetricNameLabel && !model.IsValidMetricName(model.LabelValue(l.Value)) {
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return strconv.ErrSyntax
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}
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if !model.LabelName(l.Name).IsValid() || !model.LabelValue(l.Value).IsValid() {
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return strconv.ErrSyntax
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}
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return nil
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})
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return err == nil
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}
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// Map returns a string map of the labels.
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func (ls Labels) Map() map[string]string {
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m := make(map[string]string)
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ls.Range(func(l Label) {
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m[l.Name] = l.Value
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})
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return m
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}
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// FromMap returns new sorted Labels from the given map.
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func FromMap(m map[string]string) Labels {
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l := make([]Label, 0, len(m))
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for k, v := range m {
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l = append(l, Label{Name: k, Value: v})
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}
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return New(l...)
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}
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// Builder allows modifying Labels.
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type Builder struct {
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base Labels
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del []string
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add []Label
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}
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// NewBuilder returns a new LabelsBuilder.
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func NewBuilder(base Labels) *Builder {
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b := &Builder{
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del: make([]string, 0, 5),
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add: make([]Label, 0, 5),
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}
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b.Reset(base)
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return b
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}
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// Reset clears all current state for the builder.
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func (b *Builder) Reset(base Labels) {
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b.base = base
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b.del = b.del[:0]
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b.add = b.add[:0]
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b.base.Range(func(l Label) {
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if l.Value == "" {
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b.del = append(b.del, l.Name)
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}
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})
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}
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// Del deletes the label of the given name.
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func (b *Builder) Del(ns ...string) *Builder {
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for _, n := range ns {
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for i, a := range b.add {
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if a.Name == n {
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b.add = append(b.add[:i], b.add[i+1:]...)
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}
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}
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b.del = append(b.del, n)
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}
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return b
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}
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// Keep removes all labels from the base except those with the given names.
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func (b *Builder) Keep(ns ...string) *Builder {
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b.base.Range(func(l Label) {
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for _, n := range ns {
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if l.Name == n {
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return
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}
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}
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b.del = append(b.del, l.Name)
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})
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return b
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}
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// Set the name/value pair as a label. A value of "" means delete that label.
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func (b *Builder) Set(n, v string) *Builder {
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if v == "" {
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// Empty labels are the same as missing labels.
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return b.Del(n)
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}
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for i, a := range b.add {
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if a.Name == n {
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b.add[i].Value = v
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return b
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}
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}
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b.add = append(b.add, Label{Name: n, Value: v})
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return b
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}
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func (b *Builder) Get(n string) string {
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// Del() removes entries from .add but Set() does not remove from .del, so check .add first.
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for _, a := range b.add {
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if a.Name == n {
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return a.Value
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}
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}
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if slices.Contains(b.del, n) {
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return ""
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}
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return b.base.Get(n)
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}
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// Range calls f on each label in the Builder.
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func (b *Builder) Range(f func(l Label)) {
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// Stack-based arrays to avoid heap allocation in most cases.
|
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var addStack [128]Label
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var delStack [128]string
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// Take a copy of add and del, so they are unaffected by calls to Set() or Del().
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origAdd, origDel := append(addStack[:0], b.add...), append(delStack[:0], b.del...)
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b.base.Range(func(l Label) {
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if !slices.Contains(origDel, l.Name) && !contains(origAdd, l.Name) {
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f(l)
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}
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})
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for _, a := range origAdd {
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f(a)
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}
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}
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func contains(s []Label, n string) bool {
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for _, a := range s {
|
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if a.Name == n {
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return true
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}
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}
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return false
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}
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|
|
@ -16,33 +16,14 @@
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package labels
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|
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import (
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"bytes"
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"encoding/json"
|
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"reflect"
|
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"strconv"
|
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"strings"
|
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"unsafe"
|
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|
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"github.com/cespare/xxhash/v2"
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"github.com/prometheus/common/model"
|
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"golang.org/x/exp/slices"
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||||
)
|
||||
|
||||
// Well-known label names used by Prometheus components.
|
||||
const (
|
||||
MetricName = "__name__"
|
||||
AlertName = "alertname"
|
||||
BucketLabel = "le"
|
||||
InstanceName = "instance"
|
||||
)
|
||||
|
||||
var seps = []byte{'\xff'}
|
||||
|
||||
// Label is a key/value pair of strings.
|
||||
type Label struct {
|
||||
Name, Value string
|
||||
}
|
||||
|
||||
// Labels is implemented by a single flat string holding name/value pairs.
|
||||
// Each name and value is preceded by its length in varint encoding.
|
||||
// Names are in order.
|
||||
|
|
@ -77,26 +58,6 @@ func decodeString(data string, index int) (string, int) {
|
|||
return data[index : index+size], index + size
|
||||
}
|
||||
|
||||
func (ls Labels) String() string {
|
||||
var b bytes.Buffer
|
||||
|
||||
b.WriteByte('{')
|
||||
for i := 0; i < len(ls.data); {
|
||||
if i > 0 {
|
||||
b.WriteByte(',')
|
||||
b.WriteByte(' ')
|
||||
}
|
||||
var name, value string
|
||||
name, i = decodeString(ls.data, i)
|
||||
value, i = decodeString(ls.data, i)
|
||||
b.WriteString(name)
|
||||
b.WriteByte('=')
|
||||
b.WriteString(strconv.Quote(value))
|
||||
}
|
||||
b.WriteByte('}')
|
||||
return b.String()
|
||||
}
|
||||
|
||||
// Bytes returns ls as a byte slice.
|
||||
// It uses non-printing characters and so should not be used for printing.
|
||||
func (ls Labels) Bytes(buf []byte) []byte {
|
||||
|
|
@ -109,45 +70,11 @@ func (ls Labels) Bytes(buf []byte) []byte {
|
|||
return buf
|
||||
}
|
||||
|
||||
// MarshalJSON implements json.Marshaler.
|
||||
func (ls Labels) MarshalJSON() ([]byte, error) {
|
||||
return json.Marshal(ls.Map())
|
||||
}
|
||||
|
||||
// UnmarshalJSON implements json.Unmarshaler.
|
||||
func (ls *Labels) UnmarshalJSON(b []byte) error {
|
||||
var m map[string]string
|
||||
|
||||
if err := json.Unmarshal(b, &m); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
*ls = FromMap(m)
|
||||
return nil
|
||||
}
|
||||
|
||||
// MarshalYAML implements yaml.Marshaler.
|
||||
func (ls Labels) MarshalYAML() (interface{}, error) {
|
||||
return ls.Map(), nil
|
||||
}
|
||||
|
||||
// IsZero implements yaml.IsZeroer - if we don't have this then 'omitempty' fields are always omitted.
|
||||
func (ls Labels) IsZero() bool {
|
||||
return len(ls.data) == 0
|
||||
}
|
||||
|
||||
// UnmarshalYAML implements yaml.Unmarshaler.
|
||||
func (ls *Labels) UnmarshalYAML(unmarshal func(interface{}) error) error {
|
||||
var m map[string]string
|
||||
|
||||
if err := unmarshal(&m); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
*ls = FromMap(m)
|
||||
return nil
|
||||
}
|
||||
|
||||
// MatchLabels returns a subset of Labels that matches/does not match with the provided label names based on the 'on' boolean.
|
||||
// If on is set to true, it returns the subset of labels that match with the provided label names and its inverse when 'on' is set to false.
|
||||
// TODO: This is only used in printing an error message
|
||||
|
|
@ -364,37 +291,11 @@ func (ls Labels) WithoutEmpty() Labels {
|
|||
return ls
|
||||
}
|
||||
|
||||
// IsValid checks if the metric name or label names are valid.
|
||||
func (ls Labels) IsValid() bool {
|
||||
err := ls.Validate(func(l Label) error {
|
||||
if l.Name == model.MetricNameLabel && !model.IsValidMetricName(model.LabelValue(l.Value)) {
|
||||
return strconv.ErrSyntax
|
||||
}
|
||||
if !model.LabelName(l.Name).IsValid() || !model.LabelValue(l.Value).IsValid() {
|
||||
return strconv.ErrSyntax
|
||||
}
|
||||
return nil
|
||||
})
|
||||
return err == nil
|
||||
}
|
||||
|
||||
// Equal returns whether the two label sets are equal.
|
||||
func Equal(ls, o Labels) bool {
|
||||
return ls.data == o.data
|
||||
}
|
||||
|
||||
// Map returns a string map of the labels.
|
||||
func (ls Labels) Map() map[string]string {
|
||||
m := make(map[string]string, len(ls.data)/10)
|
||||
for i := 0; i < len(ls.data); {
|
||||
var lName, lValue string
|
||||
lName, i = decodeString(ls.data, i)
|
||||
lValue, i = decodeString(ls.data, i)
|
||||
m[lName] = lValue
|
||||
}
|
||||
return m
|
||||
}
|
||||
|
||||
// EmptyLabels returns an empty Labels value, for convenience.
|
||||
func EmptyLabels() Labels {
|
||||
return Labels{}
|
||||
|
|
@ -420,15 +321,6 @@ func New(ls ...Label) Labels {
|
|||
return Labels{data: yoloString(buf)}
|
||||
}
|
||||
|
||||
// FromMap returns new sorted Labels from the given map.
|
||||
func FromMap(m map[string]string) Labels {
|
||||
l := make([]Label, 0, len(m))
|
||||
for k, v := range m {
|
||||
l = append(l, Label{Name: k, Value: v})
|
||||
}
|
||||
return New(l...)
|
||||
}
|
||||
|
||||
// FromStrings creates new labels from pairs of strings.
|
||||
func FromStrings(ss ...string) Labels {
|
||||
if len(ss)%2 != 0 {
|
||||
|
|
@ -547,124 +439,6 @@ func (ls Labels) ReleaseStrings(release func(string)) {
|
|||
release(ls.data)
|
||||
}
|
||||
|
||||
// Builder allows modifying Labels.
|
||||
type Builder struct {
|
||||
base Labels
|
||||
del []string
|
||||
add []Label
|
||||
}
|
||||
|
||||
// NewBuilder returns a new LabelsBuilder.
|
||||
func NewBuilder(base Labels) *Builder {
|
||||
b := &Builder{
|
||||
del: make([]string, 0, 5),
|
||||
add: make([]Label, 0, 5),
|
||||
}
|
||||
b.Reset(base)
|
||||
return b
|
||||
}
|
||||
|
||||
// Reset clears all current state for the builder.
|
||||
func (b *Builder) Reset(base Labels) {
|
||||
b.base = base
|
||||
b.del = b.del[:0]
|
||||
b.add = b.add[:0]
|
||||
for i := 0; i < len(base.data); {
|
||||
var lName, lValue string
|
||||
lName, i = decodeString(base.data, i)
|
||||
lValue, i = decodeString(base.data, i)
|
||||
if lValue == "" {
|
||||
b.del = append(b.del, lName)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Del deletes the label of the given name.
|
||||
func (b *Builder) Del(ns ...string) *Builder {
|
||||
for _, n := range ns {
|
||||
for i, a := range b.add {
|
||||
if a.Name == n {
|
||||
b.add = append(b.add[:i], b.add[i+1:]...)
|
||||
}
|
||||
}
|
||||
b.del = append(b.del, n)
|
||||
}
|
||||
return b
|
||||
}
|
||||
|
||||
// Keep removes all labels from the base except those with the given names.
|
||||
func (b *Builder) Keep(ns ...string) *Builder {
|
||||
Outer:
|
||||
for i := 0; i < len(b.base.data); {
|
||||
var lName string
|
||||
lName, i = decodeString(b.base.data, i)
|
||||
_, i = decodeString(b.base.data, i)
|
||||
for _, n := range ns {
|
||||
if lName == n {
|
||||
continue Outer
|
||||
}
|
||||
}
|
||||
b.del = append(b.del, lName)
|
||||
}
|
||||
return b
|
||||
}
|
||||
|
||||
// Set the name/value pair as a label. A value of "" means delete that label.
|
||||
func (b *Builder) Set(n, v string) *Builder {
|
||||
if v == "" {
|
||||
// Empty labels are the same as missing labels.
|
||||
return b.Del(n)
|
||||
}
|
||||
for i, a := range b.add {
|
||||
if a.Name == n {
|
||||
b.add[i].Value = v
|
||||
return b
|
||||
}
|
||||
}
|
||||
b.add = append(b.add, Label{Name: n, Value: v})
|
||||
|
||||
return b
|
||||
}
|
||||
|
||||
func (b *Builder) Get(n string) string {
|
||||
// Del() removes entries from .add but Set() does not remove from .del, so check .add first.
|
||||
for _, a := range b.add {
|
||||
if a.Name == n {
|
||||
return a.Value
|
||||
}
|
||||
}
|
||||
if slices.Contains(b.del, n) {
|
||||
return ""
|
||||
}
|
||||
return b.base.Get(n)
|
||||
}
|
||||
|
||||
// Range calls f on each label in the Builder.
|
||||
func (b *Builder) Range(f func(l Label)) {
|
||||
// Stack-based arrays to avoid heap allocation in most cases.
|
||||
var addStack [128]Label
|
||||
var delStack [128]string
|
||||
// Take a copy of add and del, so they are unaffected by calls to Set() or Del().
|
||||
origAdd, origDel := append(addStack[:0], b.add...), append(delStack[:0], b.del...)
|
||||
b.base.Range(func(l Label) {
|
||||
if !slices.Contains(origDel, l.Name) && !contains(origAdd, l.Name) {
|
||||
f(l)
|
||||
}
|
||||
})
|
||||
for _, a := range origAdd {
|
||||
f(a)
|
||||
}
|
||||
}
|
||||
|
||||
func contains(s []Label, n string) bool {
|
||||
for _, a := range s {
|
||||
if a.Name == n {
|
||||
return true
|
||||
}
|
||||
}
|
||||
return false
|
||||
}
|
||||
|
||||
// Labels returns the labels from the builder.
|
||||
// If no modifications were made, the original labels are returned.
|
||||
func (b *Builder) Labels() Labels {
|
||||
|
|
|
|||
Loading…
Reference in New Issue