Create an internal package

This is for types we don't want to export but which are used in
different packages within client_golang.

Currently, that's only NormalizeMetricFamilies (used in the prometheus
package and in the testutil package). More to be added as needed.

Signed-off-by: beorn7 <beorn@soundcloud.com>
This commit is contained in:
beorn7 2018-09-02 23:36:34 +02:00
parent 5ba0993f6f
commit 7be86f93c1
3 changed files with 92 additions and 131 deletions

View File

@ -0,0 +1,85 @@
// Copyright 2018 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.
package internal
import (
"sort"
dto "github.com/prometheus/client_model/go"
)
// metricSorter is a sortable slice of *dto.Metric.
type metricSorter []*dto.Metric
func (s metricSorter) Len() int {
return len(s)
}
func (s metricSorter) Swap(i, j int) {
s[i], s[j] = s[j], s[i]
}
func (s metricSorter) Less(i, j int) bool {
if len(s[i].Label) != len(s[j].Label) {
// This should not happen. The metrics are
// inconsistent. However, we have to deal with the fact, as
// people might use custom collectors or metric family injection
// to create inconsistent metrics. So let's simply compare the
// number of labels in this case. That will still yield
// reproducible sorting.
return len(s[i].Label) < len(s[j].Label)
}
for n, lp := range s[i].Label {
vi := lp.GetValue()
vj := s[j].Label[n].GetValue()
if vi != vj {
return vi < vj
}
}
// We should never arrive here. Multiple metrics with the same
// label set in the same scrape will lead to undefined ingestion
// behavior. However, as above, we have to provide stable sorting
// here, even for inconsistent metrics. So sort equal metrics
// by their timestamp, with missing timestamps (implying "now")
// coming last.
if s[i].TimestampMs == nil {
return false
}
if s[j].TimestampMs == nil {
return true
}
return s[i].GetTimestampMs() < s[j].GetTimestampMs()
}
// NormalizeMetricFamilies returns a MetricFamily slice with empty
// MetricFamilies pruned and the remaining MetricFamilies sorted by name within
// the slice, with the contained Metrics sorted within each MetricFamily.
func NormalizeMetricFamilies(metricFamiliesByName map[string]*dto.MetricFamily) []*dto.MetricFamily {
for _, mf := range metricFamiliesByName {
sort.Sort(metricSorter(mf.Metric))
}
names := make([]string, 0, len(metricFamiliesByName))
for name, mf := range metricFamiliesByName {
if len(mf.Metric) > 0 {
names = append(names, name)
}
}
sort.Strings(names)
result := make([]*dto.MetricFamily, 0, len(names))
for _, name := range names {
result = append(result, metricFamiliesByName[name])
}
return result
}

View File

@ -26,6 +26,8 @@ import (
"github.com/golang/protobuf/proto" "github.com/golang/protobuf/proto"
dto "github.com/prometheus/client_model/go" dto "github.com/prometheus/client_model/go"
"github.com/prometheus/client_golang/prometheus/internal"
) )
const ( const (
@ -527,7 +529,7 @@ func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
break break
} }
} }
return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap() return internal.NormalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
} }
// processMetric is an internal helper method only used by the Gather method. // processMetric is an internal helper method only used by the Gather method.
@ -707,72 +709,7 @@ func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) {
} }
} }
} }
return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap() return internal.NormalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
}
// metricSorter is a sortable slice of *dto.Metric.
type metricSorter []*dto.Metric
func (s metricSorter) Len() int {
return len(s)
}
func (s metricSorter) Swap(i, j int) {
s[i], s[j] = s[j], s[i]
}
func (s metricSorter) Less(i, j int) bool {
if len(s[i].Label) != len(s[j].Label) {
// This should not happen. The metrics are
// inconsistent. However, we have to deal with the fact, as
// people might use custom collectors or metric family injection
// to create inconsistent metrics. So let's simply compare the
// number of labels in this case. That will still yield
// reproducible sorting.
return len(s[i].Label) < len(s[j].Label)
}
for n, lp := range s[i].Label {
vi := lp.GetValue()
vj := s[j].Label[n].GetValue()
if vi != vj {
return vi < vj
}
}
// We should never arrive here. Multiple metrics with the same
// label set in the same scrape will lead to undefined ingestion
// behavior. However, as above, we have to provide stable sorting
// here, even for inconsistent metrics. So sort equal metrics
// by their timestamp, with missing timestamps (implying "now")
// coming last.
if s[i].TimestampMs == nil {
return false
}
if s[j].TimestampMs == nil {
return true
}
return s[i].GetTimestampMs() < s[j].GetTimestampMs()
}
// normalizeMetricFamilies returns a MetricFamily slice with empty
// MetricFamilies pruned and the remaining MetricFamilies sorted by name within
// the slice, with the contained Metrics sorted within each MetricFamily.
func normalizeMetricFamilies(metricFamiliesByName map[string]*dto.MetricFamily) []*dto.MetricFamily {
for _, mf := range metricFamiliesByName {
sort.Sort(metricSorter(mf.Metric))
}
names := make([]string, 0, len(metricFamiliesByName))
for name, mf := range metricFamiliesByName {
if len(mf.Metric) > 0 {
names = append(names, name)
}
}
sort.Strings(names)
result := make([]*dto.MetricFamily, 0, len(names))
for _, name := range names {
result = append(result, metricFamiliesByName[name])
}
return result
} }
// checkSuffixCollisions checks for collisions with the “magic” suffixes the // checkSuffixCollisions checks for collisions with the “magic” suffixes the

View File

@ -18,13 +18,13 @@ import (
"fmt" "fmt"
"io" "io"
"reflect" "reflect"
"sort"
"github.com/prometheus/common/expfmt" "github.com/prometheus/common/expfmt"
dto "github.com/prometheus/client_model/go" dto "github.com/prometheus/client_model/go"
"github.com/prometheus/client_golang/prometheus" "github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/internal"
) )
// CollectAndCompare registers the provided Collector with a newly created // CollectAndCompare registers the provided Collector with a newly created
@ -56,7 +56,7 @@ func GatherAndCompare(g prometheus.Gatherer, expected io.Reader, metricNames ...
return fmt.Errorf("parsing expected metrics failed: %s", err) return fmt.Errorf("parsing expected metrics failed: %s", err)
} }
if !reflect.DeepEqual(metrics, normalizeMetricFamilies(expectedMetrics)) { if !reflect.DeepEqual(metrics, internal.NormalizeMetricFamilies(expectedMetrics)) {
// Encode the gathered output to the readable text format for comparison. // Encode the gathered output to the readable text format for comparison.
var buf1 bytes.Buffer var buf1 bytes.Buffer
enc := expfmt.NewEncoder(&buf1, expfmt.FmtText) enc := expfmt.NewEncoder(&buf1, expfmt.FmtText)
@ -69,7 +69,7 @@ func GatherAndCompare(g prometheus.Gatherer, expected io.Reader, metricNames ...
// the registry does to spot differences more easily. // the registry does to spot differences more easily.
var buf2 bytes.Buffer var buf2 bytes.Buffer
enc = expfmt.NewEncoder(&buf2, expfmt.FmtText) enc = expfmt.NewEncoder(&buf2, expfmt.FmtText)
for _, mf := range normalizeMetricFamilies(expectedMetrics) { for _, mf := range internal.NormalizeMetricFamilies(expectedMetrics) {
if err := enc.Encode(mf); err != nil { if err := enc.Encode(mf); err != nil {
return fmt.Errorf("encoding result failed: %s", err) return fmt.Errorf("encoding result failed: %s", err)
} }
@ -100,64 +100,3 @@ func filterMetrics(metrics []*dto.MetricFamily, names []string) []*dto.MetricFam
} }
return filtered return filtered
} }
// The below sorting code is copied form the Prometheus client library modulo the added
// label pair sorting.
// https://github.com/prometheus/client_golang/blob/ea6e1db4cb8127eeb0b6954f7320363e5451820f/prometheus/registry.go#L642-L684
// metricSorter is a sortable slice of *dto.Metric.
type metricSorter []*dto.Metric
func (s metricSorter) Len() int {
return len(s)
}
func (s metricSorter) Swap(i, j int) {
s[i], s[j] = s[j], s[i]
}
func (s metricSorter) Less(i, j int) bool {
sort.Sort(prometheus.LabelPairSorter(s[i].Label))
sort.Sort(prometheus.LabelPairSorter(s[j].Label))
if len(s[i].Label) != len(s[j].Label) {
return len(s[i].Label) < len(s[j].Label)
}
for n, lp := range s[i].Label {
vi := lp.GetValue()
vj := s[j].Label[n].GetValue()
if vi != vj {
return vi < vj
}
}
if s[i].TimestampMs == nil {
return false
}
if s[j].TimestampMs == nil {
return true
}
return s[i].GetTimestampMs() < s[j].GetTimestampMs()
}
// normalizeMetricFamilies returns a MetricFamily slice with empty
// MetricFamilies pruned and the remaining MetricFamilies sorted by name within
// the slice, with the contained Metrics sorted within each MetricFamily.
func normalizeMetricFamilies(metricFamiliesByName map[string]*dto.MetricFamily) []*dto.MetricFamily {
for _, mf := range metricFamiliesByName {
sort.Sort(metricSorter(mf.Metric))
}
names := make([]string, 0, len(metricFamiliesByName))
for name, mf := range metricFamiliesByName {
if len(mf.Metric) > 0 {
names = append(names, name)
}
}
sort.Strings(names)
result := make([]*dto.MetricFamily, 0, len(names))
for _, name := range names {
result = append(result, metricFamiliesByName[name])
}
return result
}