Merge pull request #445 from prometheus/beorn7/testing

Add testutil package
This commit is contained in:
Björn Rabenstein 2018-09-03 00:31:34 +02:00 committed by GitHub
commit a10423e9da
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
4 changed files with 306 additions and 67 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

@ -0,0 +1,102 @@
// 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 testutil
import (
"bytes"
"fmt"
"io"
"reflect"
"github.com/prometheus/common/expfmt"
dto "github.com/prometheus/client_model/go"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/internal"
)
// CollectAndCompare registers the provided Collector with a newly created
// pedantic Registry. It then does the same as GatherAndCompare, gathering the
// metrics from the pedantic Registry.
func CollectAndCompare(c prometheus.Collector, expected io.Reader, metricNames ...string) error {
reg := prometheus.NewPedanticRegistry()
if err := reg.Register(c); err != nil {
return fmt.Errorf("registering collector failed: %s", err)
}
return GatherAndCompare(reg, expected, metricNames...)
}
// GatherAndCompare gathers all metrics from the provided Gatherer and compares
// it to an expected output read from the provided Reader in the Prometheus text
// exposition format. If any metricNames are provided, only metrics with those
// names are compared.
func GatherAndCompare(g prometheus.Gatherer, expected io.Reader, metricNames ...string) error {
metrics, err := g.Gather()
if err != nil {
return fmt.Errorf("gathering metrics failed: %s", err)
}
if metricNames != nil {
metrics = filterMetrics(metrics, metricNames)
}
var tp expfmt.TextParser
expectedMetrics, err := tp.TextToMetricFamilies(expected)
if err != nil {
return fmt.Errorf("parsing expected metrics failed: %s", err)
}
if !reflect.DeepEqual(metrics, internal.NormalizeMetricFamilies(expectedMetrics)) {
// Encode the gathered output to the readable text format for comparison.
var buf1 bytes.Buffer
enc := expfmt.NewEncoder(&buf1, expfmt.FmtText)
for _, mf := range metrics {
if err := enc.Encode(mf); err != nil {
return fmt.Errorf("encoding result failed: %s", err)
}
}
// Encode normalized expected metrics again to generate them in the same ordering
// the registry does to spot differences more easily.
var buf2 bytes.Buffer
enc = expfmt.NewEncoder(&buf2, expfmt.FmtText)
for _, mf := range internal.NormalizeMetricFamilies(expectedMetrics) {
if err := enc.Encode(mf); err != nil {
return fmt.Errorf("encoding result failed: %s", err)
}
}
return fmt.Errorf(`
metric output does not match expectation; want:
%s
got:
%s
`, buf2.String(), buf1.String())
}
return nil
}
func filterMetrics(metrics []*dto.MetricFamily, names []string) []*dto.MetricFamily {
var filtered []*dto.MetricFamily
for _, m := range metrics {
for _, name := range names {
if m.GetName() == name {
filtered = append(filtered, m)
break
}
}
}
return filtered
}

View File

@ -0,0 +1,115 @@
// 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 testutil
import (
"strings"
"testing"
"github.com/prometheus/client_golang/prometheus"
)
func TestCollectAndCompare(t *testing.T) {
const metadata = `
# HELP some_total A value that represents a counter.
# TYPE some_total counter
`
c := prometheus.NewCounter(prometheus.CounterOpts{
Name: "some_total",
Help: "A value that represents a counter.",
ConstLabels: prometheus.Labels{
"label1": "value1",
},
})
c.Inc()
expected := `
some_total{ label1 = "value1" } 1
`
if err := CollectAndCompare(c, strings.NewReader(metadata+expected), "some_total"); err != nil {
t.Errorf("unexpected collecting result:\n%s", err)
}
}
func TestNoMetricFilter(t *testing.T) {
const metadata = `
# HELP some_total A value that represents a counter.
# TYPE some_total counter
`
c := prometheus.NewCounter(prometheus.CounterOpts{
Name: "some_total",
Help: "A value that represents a counter.",
ConstLabels: prometheus.Labels{
"label1": "value1",
},
})
c.Inc()
expected := `
some_total{label1="value1"} 1
`
if err := CollectAndCompare(c, strings.NewReader(metadata+expected)); err != nil {
t.Errorf("unexpected collecting result:\n%s", err)
}
}
func TestMetricNotFound(t *testing.T) {
const metadata = `
# HELP some_other_metric A value that represents a counter.
# TYPE some_other_metric counter
`
c := prometheus.NewCounter(prometheus.CounterOpts{
Name: "some_total",
Help: "A value that represents a counter.",
ConstLabels: prometheus.Labels{
"label1": "value1",
},
})
c.Inc()
expected := `
some_other_metric{label1="value1"} 1
`
expectedError := `
metric output does not match expectation; want:
# HELP some_other_metric A value that represents a counter.
# TYPE some_other_metric counter
some_other_metric{label1="value1"} 1
got:
# HELP some_total A value that represents a counter.
# TYPE some_total counter
some_total{label1="value1"} 1
`
err := CollectAndCompare(c, strings.NewReader(metadata+expected))
if err == nil {
t.Error("Expected error, got no error.")
}
if err.Error() != expectedError {
t.Errorf("Expected\n%#+v\nGot:\n%#+v\n", expectedError, err.Error())
}
}