Move escapeMetricName to mapper

Signed-off-by: bakins <brian@akins.org>
This commit is contained in:
bakins 2020-01-16 08:48:17 -05:00
parent 5aae305b35
commit e60f77df30
4 changed files with 133 additions and 98 deletions

View file

@ -54,61 +54,6 @@ type Exporter struct {
logger log.Logger logger log.Logger
} }
// Replace invalid characters in the metric name with "_"
// Valid characters are a-z, A-Z, 0-9, and _
func escapeMetricName(metricName string) string {
metricLen := len(metricName)
if metricLen == 0 {
return ""
}
escaped := false
var sb strings.Builder
// If a metric starts with a digit, allocate the memory and prepend an
// underscore.
if metricName[0] >= '0' && metricName[0] <= '9' {
escaped = true
sb.Grow(metricLen + 1)
sb.WriteByte('_')
}
// This is an character replacement method optimized for this limited
// use case. It is much faster than using a regex.
offset := 0
for i, c := range metricName {
// Seek forward, skipping valid characters until we find one that needs
// to be replaced, then add all the characters we've seen so far to the
// string.Builder.
if (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') ||
(c >= '0' && c <= '9') || (c == '_') {
// Character is valid, so skip over it without doing anything.
} else {
if !escaped {
// Up until now we've been lazy and avoided actually allocating
// memory. Unfortunately we've now determined this string needs
// escaping, so allocate the buffer for the whole string.
escaped = true
sb.Grow(metricLen)
}
sb.WriteString(metricName[offset:i])
offset = i + utf8.RuneLen(c)
sb.WriteByte('_')
}
}
if !escaped {
// This is the happy path where nothing had to be escaped, so we can
// avoid doing anything.
return metricName
}
if offset < metricLen {
sb.WriteString(metricName[offset:])
}
return sb.String()
}
// Listen handles all events sent to the given channel sequentially. It // Listen handles all events sent to the given channel sequentially. It
// terminates when the channel is closed. // terminates when the channel is closed.
func (b *Exporter) Listen(e <-chan Events) { func (b *Exporter) Listen(e <-chan Events) {
@ -159,14 +104,14 @@ func (b *Exporter) handleEvent(event Event) {
errorEventStats.WithLabelValues("empty_metric_name").Inc() errorEventStats.WithLabelValues("empty_metric_name").Inc()
return return
} }
metricName = escapeMetricName(mapping.Name) metricName = mapper.EscapeMetricName(mapping.Name)
for label, value := range labels { for label, value := range labels {
prometheusLabels[label] = value prometheusLabels[label] = value
} }
eventsActions.WithLabelValues(string(mapping.Action)).Inc() eventsActions.WithLabelValues(string(mapping.Action)).Inc()
} else { } else {
eventsUnmapped.Inc() eventsUnmapped.Inc()
metricName = escapeMetricName(event.MetricName()) metricName = mapper.EscapeMetricName(event.MetricName())
} }
switch ev := event.(type) { switch ev := event.(type) {
@ -298,7 +243,7 @@ func parseTag(component, tag string, separator rune, labels map[string]string, l
tagErrors.Inc() tagErrors.Inc()
level.Debug(logger).Log("msg", "Malformed name tag", "k", k, "v", v, "component", component) level.Debug(logger).Log("msg", "Malformed name tag", "k", k, "v", v, "component", component)
} else { } else {
labels[escapeMetricName(k)] = v labels[mapper.EscapeMetricName(k)] = v
} }
return return
} }

View file

@ -682,25 +682,6 @@ func (ml *mockStatsDTCPListener) handlePacket(packet []byte) {
ml.handleConn(sc) ml.handleConn(sc)
} }
func TestEscapeMetricName(t *testing.T) {
scenarios := map[string]string{
"clean": "clean",
"0starts_with_digit": "_0starts_with_digit",
"with_underscore": "with_underscore",
"with.dot": "with_dot",
"with😱emoji": "with_emoji",
"with.*.multiple": "with___multiple",
"test.web-server.foo.bar": "test_web_server_foo_bar",
"": "",
}
for in, want := range scenarios {
if got := escapeMetricName(in); want != got {
t.Errorf("expected `%s` to be escaped to `%s`, got `%s`", in, want, got)
}
}
}
// TestTtlExpiration validates expiration of time series. // TestTtlExpiration validates expiration of time series.
// foobar metric without mapping should expire with default ttl of 1s // foobar metric without mapping should expire with default ttl of 1s
// bazqux metric should expire with ttl of 2s // bazqux metric should expire with ttl of 2s
@ -922,27 +903,6 @@ func getTelemetryCounterValue(counter prometheus.Counter) float64 {
return metric.Counter.GetValue() return metric.Counter.GetValue()
} }
func BenchmarkEscapeMetricName(b *testing.B) {
scenarios := []string{
"clean",
"0starts_with_digit",
"with_underscore",
"with.dot",
"with😱emoji",
"with.*.multiple",
"test.web-server.foo.bar",
"",
}
for _, s := range scenarios {
b.Run(s, func(b *testing.B) {
for n := 0; n < b.N; n++ {
escapeMetricName(s)
}
})
}
}
func BenchmarkParseDogStatsDTags(b *testing.B) { func BenchmarkParseDogStatsDTags(b *testing.B) {
scenarios := map[string]string{ scenarios := map[string]string{
"1 tag w/hash": "#test:tag", "1 tag w/hash": "#test:tag",

74
pkg/mapper/escape.go Normal file
View file

@ -0,0 +1,74 @@
// 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.
package mapper
import (
"strings"
"unicode/utf8"
)
// EscapeMetricName replaces invalid characters in the metric name with "_"
// Valid characters are a-z, A-Z, 0-9, and _
func EscapeMetricName(metricName string) string {
metricLen := len(metricName)
if metricLen == 0 {
return ""
}
escaped := false
var sb strings.Builder
// If a metric starts with a digit, allocate the memory and prepend an
// underscore.
if metricName[0] >= '0' && metricName[0] <= '9' {
escaped = true
sb.Grow(metricLen + 1)
sb.WriteByte('_')
}
// This is an character replacement method optimized for this limited
// use case. It is much faster than using a regex.
offset := 0
for i, c := range metricName {
// Seek forward, skipping valid characters until we find one that needs
// to be replaced, then add all the characters we've seen so far to the
// string.Builder.
if (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') ||
(c >= '0' && c <= '9') || (c == '_') {
// Character is valid, so skip over it without doing anything.
} else {
if !escaped {
// Up until now we've been lazy and avoided actually allocating
// memory. Unfortunately we've now determined this string needs
// escaping, so allocate the buffer for the whole string.
escaped = true
sb.Grow(metricLen)
}
sb.WriteString(metricName[offset:i])
offset = i + utf8.RuneLen(c)
sb.WriteByte('_')
}
}
if !escaped {
// This is the happy path where nothing had to be escaped, so we can
// avoid doing anything.
return metricName
}
if offset < metricLen {
sb.WriteString(metricName[offset:])
}
return sb.String()
}

56
pkg/mapper/escape_test.go Normal file
View file

@ -0,0 +1,56 @@
// 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.
package mapper
import "testing"
func TestEscapeMetricName(t *testing.T) {
scenarios := map[string]string{
"clean": "clean",
"0starts_with_digit": "_0starts_with_digit",
"with_underscore": "with_underscore",
"with.dot": "with_dot",
"with😱emoji": "with_emoji",
"with.*.multiple": "with___multiple",
"test.web-server.foo.bar": "test_web_server_foo_bar",
"": "",
}
for in, want := range scenarios {
if got := EscapeMetricName(in); want != got {
t.Errorf("expected `%s` to be escaped to `%s`, got `%s`", in, want, got)
}
}
}
func BenchmarkEscapeMetricName(b *testing.B) {
scenarios := []string{
"clean",
"0starts_with_digit",
"with_underscore",
"with.dot",
"with😱emoji",
"with.*.multiple",
"test.web-server.foo.bar",
"",
}
for _, s := range scenarios {
b.Run(s, func(b *testing.B) {
for n := 0; n < b.N; n++ {
EscapeMetricName(s)
}
})
}
}