forked from prometheus/alertmanager
-
Notifications
You must be signed in to change notification settings - Fork 0
/
match.go
172 lines (150 loc) · 4.01 KB
/
match.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
// Copyright 2015 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 types
import (
"fmt"
"regexp"
"sort"
"bytes"
"github.com/prometheus/common/model"
)
// Matcher defines a matching rule for the value of a given label.
type Matcher struct {
Name string `json:"name"`
Value string `json:"value"`
IsRegex bool `json:"isRegex"`
regex *regexp.Regexp
}
// Init internals of the Matcher. Must be called before using Match.
func (m *Matcher) Init() error {
if !m.IsRegex {
return nil
}
re, err := regexp.Compile("^(?:" + m.Value + ")$")
if err == nil {
m.regex = re
}
return err
}
func (m *Matcher) String() string {
if m.IsRegex {
return fmt.Sprintf("%s=~%q", m.Name, m.Value)
}
return fmt.Sprintf("%s=%q", m.Name, m.Value)
}
// Validate returns true iff all fields of the matcher have valid values.
func (m *Matcher) Validate() error {
if !model.LabelName(m.Name).IsValid() {
return fmt.Errorf("invalid name %q", m.Name)
}
if m.IsRegex {
if _, err := regexp.Compile(m.Value); err != nil {
return fmt.Errorf("invalid regular expression %q", m.Value)
}
} else if !model.LabelValue(m.Value).IsValid() || len(m.Value) == 0 {
return fmt.Errorf("invalid value %q", m.Value)
}
return nil
}
// Match checks whether the label of the matcher has the specified
// matching value.
func (m *Matcher) Match(lset model.LabelSet) bool {
// Unset labels are treated as unset labels globally. Thus, if a
// label is not set we retrieve the empty label which is correct
// for the comparison below.
v := lset[model.LabelName(m.Name)]
if m.IsRegex {
return m.regex.MatchString(string(v))
}
return string(v) == m.Value
}
// NewMatcher returns a new matcher that compares against equality of
// the given value.
func NewMatcher(name model.LabelName, value string) *Matcher {
return &Matcher{
Name: string(name),
Value: value,
IsRegex: false,
}
}
// NewRegexMatcher returns a new matcher that compares values against
// a regular expression. The matcher is already initialized.
//
// TODO(fabxc): refactor usage.
func NewRegexMatcher(name model.LabelName, re *regexp.Regexp) *Matcher {
return &Matcher{
Name: string(name),
Value: re.String(),
IsRegex: true,
regex: re,
}
}
// Matchers provides the Match and Fingerprint methods for a slice of Matchers.
// Matchers must always be sorted.
type Matchers []*Matcher
// NewMatchers returns the given Matchers sorted.
func NewMatchers(ms ...*Matcher) Matchers {
m := Matchers(ms)
sort.Sort(m)
return m
}
func (ms Matchers) Len() int { return len(ms) }
func (ms Matchers) Swap(i, j int) { ms[i], ms[j] = ms[j], ms[i] }
func (ms Matchers) Less(i, j int) bool {
if ms[i].Name > ms[j].Name {
return false
}
if ms[i].Name < ms[j].Name {
return true
}
if ms[i].Value > ms[j].Value {
return false
}
if ms[i].Value < ms[j].Value {
return true
}
return !ms[i].IsRegex && ms[j].IsRegex
}
// Equal returns whether both Matchers are equal.
func (ms Matchers) Equal(o Matchers) bool {
if len(ms) != len(o) {
return false
}
for i, a := range ms {
if *a != *o[i] {
return false
}
}
return true
}
// Match checks whether all matchers are fulfilled against the given label set.
func (ms Matchers) Match(lset model.LabelSet) bool {
for _, m := range ms {
if !m.Match(lset) {
return false
}
}
return true
}
func (ms Matchers) String() string {
var buf bytes.Buffer
buf.WriteByte('{')
for i, m := range ms {
if i > 0 {
buf.WriteByte(',')
}
buf.WriteString(m.String())
}
buf.WriteByte('}')
return buf.String()
}