prometheus/storage/generic.go

139 lines
3.6 KiB
Go

// Copyright 2020 The Prometheus Authors
// 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.
// This file holds boilerplate adapters for generic MergeSeriesSet and MergeQuerier functions, so we can have one optimized
// solution that works for both ChunkSeriesSet as well as SeriesSet.
package storage
import "github.com/prometheus/prometheus/pkg/labels"
type genericQuerier interface {
LabelQuerier
Select(bool, *SelectHints, ...*labels.Matcher) genericSeriesSet
}
type genericSeriesSet interface {
Next() bool
At() Labels
Err() error
Warnings() Warnings
}
type genericSeriesMergeFunc func(...Labels) Labels
type genericSeriesSetAdapter struct {
SeriesSet
}
func (a *genericSeriesSetAdapter) At() Labels {
return a.SeriesSet.At()
}
type genericChunkSeriesSetAdapter struct {
ChunkSeriesSet
}
func (a *genericChunkSeriesSetAdapter) At() Labels {
return a.ChunkSeriesSet.At()
}
type genericQuerierAdapter struct {
LabelQuerier
// One-of. If both are set, Querier will be used.
q Querier
cq ChunkQuerier
}
func (q *genericQuerierAdapter) Select(sortSeries bool, hints *SelectHints, matchers ...*labels.Matcher) genericSeriesSet {
if q.q != nil {
return &genericSeriesSetAdapter{q.q.Select(sortSeries, hints, matchers...)}
}
return &genericChunkSeriesSetAdapter{q.cq.Select(sortSeries, hints, matchers...)}
}
func newGenericQuerierFrom(q Querier) genericQuerier {
return &genericQuerierAdapter{LabelQuerier: q, q: q}
}
func newGenericQuerierFromChunk(cq ChunkQuerier) genericQuerier {
return &genericQuerierAdapter{LabelQuerier: cq, cq: cq}
}
type querierAdapter struct {
genericQuerier
}
type seriesSetAdapter struct {
genericSeriesSet
}
func (a *seriesSetAdapter) At() Series {
return a.genericSeriesSet.At().(Series)
}
func (q *querierAdapter) Select(sortSeries bool, hints *SelectHints, matchers ...*labels.Matcher) SeriesSet {
return &seriesSetAdapter{q.genericQuerier.Select(sortSeries, hints, matchers...)}
}
type chunkQuerierAdapter struct {
genericQuerier
}
type chunkSeriesSetAdapter struct {
genericSeriesSet
}
func (a *chunkSeriesSetAdapter) At() ChunkSeries {
return a.genericSeriesSet.At().(ChunkSeries)
}
func (q *chunkQuerierAdapter) Select(sortSeries bool, hints *SelectHints, matchers ...*labels.Matcher) ChunkSeriesSet {
return &chunkSeriesSetAdapter{q.genericQuerier.Select(sortSeries, hints, matchers...)}
}
type seriesMergerAdapter struct {
VerticalSeriesMergeFunc
}
func (a *seriesMergerAdapter) Merge(s ...Labels) Labels {
buf := make([]Series, 0, len(s))
for _, ser := range s {
buf = append(buf, ser.(Series))
}
return a.VerticalSeriesMergeFunc(buf...)
}
type chunkSeriesMergerAdapter struct {
VerticalChunkSeriesMergeFunc
}
func (a *chunkSeriesMergerAdapter) Merge(s ...Labels) Labels {
buf := make([]ChunkSeries, 0, len(s))
for _, ser := range s {
buf = append(buf, ser.(ChunkSeries))
}
return a.VerticalChunkSeriesMergeFunc(buf...)
}
type noopGenericSeriesSet struct{}
func (noopGenericSeriesSet) Next() bool { return false }
func (noopGenericSeriesSet) At() Labels { return nil }
func (noopGenericSeriesSet) Err() error { return nil }
func (noopGenericSeriesSet) Warnings() Warnings { return nil }