prometheus/storage/metric/matcher.go
Julius Volz 01f652cb4c Separate storage implementation from interfaces.
This was initially motivated by wanting to distribute the rule checker
tool under `tools/rule_checker`. However, this was not possible without
also distributing the LevelDB dynamic libraries because the tool
transitively depended on Levigo:

rule checker -> query layer -> tiered storage layer -> leveldb

This change separates external storage interfaces from the
implementation (tiered storage, leveldb storage, memory storage) by
putting them into separate packages:

- storage/metric: public, implementation-agnostic interfaces
- storage/metric/tiered: tiered storage implementation, including memory
                         and LevelDB storage.

I initially also considered splitting up the implementation into
separate packages for tiered storage, memory storage, and LevelDB
storage, but these are currently so intertwined that it would be another
major project in itself.

The query layers and most other parts of Prometheus now have notion of
the storage implementation anymore and just use whatever implementation
they get passed in via interfaces.

The rule_checker is now a static binary :)

Change-Id: I793bbf631a8648ca31790e7e772ecf9c2b92f7a0
2014-04-16 13:30:19 +02:00

101 lines
2.4 KiB
Go

// Copyright 2014 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 (
"regexp"
clientmodel "github.com/prometheus/client_golang/model"
)
// MatchType is an enum for label matching types.
type MatchType int
// Possible MatchTypes.
const (
Equal MatchType = iota
NotEqual
RegexMatch
RegexNoMatch
)
func (m MatchType) String() string {
typeToStr := map[MatchType]string{
Equal: "=",
NotEqual: "!=",
RegexMatch: "=~",
RegexNoMatch: "!~",
}
if str, ok := typeToStr[m]; ok {
return str
}
panic("unknown match type")
}
// LabelMatchers is a slice of LabelMatcher objects.
type LabelMatchers []*LabelMatcher
// LabelMatcher models the matching of a label.
type LabelMatcher struct {
Type MatchType
Name clientmodel.LabelName
Value clientmodel.LabelValue
re *regexp.Regexp
}
// NewLabelMatcher returns a LabelMatcher object ready to use.
func NewLabelMatcher(matchType MatchType, name clientmodel.LabelName, value clientmodel.LabelValue) (*LabelMatcher, error) {
m := &LabelMatcher{
Type: matchType,
Name: name,
Value: value,
}
if matchType == RegexMatch || matchType == RegexNoMatch {
re, err := regexp.Compile(string(value))
if err != nil {
return nil, err
}
m.re = re
}
return m, nil
}
// Match returns true if the label matcher matches the supplied label value.
func (m *LabelMatcher) Match(v clientmodel.LabelValue) bool {
switch m.Type {
case Equal:
return m.Value == v
case NotEqual:
return m.Value != v
case RegexMatch:
return m.re.MatchString(string(v))
case RegexNoMatch:
return !m.re.MatchString(string(v))
default:
panic("invalid match type")
}
}
// Filter takes a list of label values and returns all label values which match
// the label matcher.
func (m *LabelMatcher) Filter(in clientmodel.LabelValues) clientmodel.LabelValues {
out := clientmodel.LabelValues{}
for _, v := range in {
if m.Match(v) {
out = append(out, v)
}
}
return out
}