forked from prometheus/statsd_exporter
/
bridge.go
364 lines (320 loc) · 9.11 KB
/
bridge.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
// Copyright 2013 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 main
import (
"bytes"
"encoding/binary"
"fmt"
"hash/fnv"
"net"
"regexp"
"strconv"
"strings"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/common/model"
"github.com/prometheus/log"
)
const (
defaultHelp = "Metric autogenerated by statsd_bridge."
regErrF = "A change of configuration created inconsistent metrics for " +
"%q. You have to restart the statsd_bridge, and you should " +
"consider the effects on your monitoring setup. Error: %s"
)
var (
illegalCharsRE = regexp.MustCompile(`[^a-zA-Z0-9_]`)
hash = fnv.New64a()
strBuf bytes.Buffer // Used for hashing.
intBuf = make([]byte, 8)
)
// hashNameAndLabels returns a hash value of the provided name string and all
// the label names and values in the provided labels map.
//
// Not safe for concurrent use! (Uses a shared buffer and hasher to save on
// allocations.)
func hashNameAndLabels(name string, labels prometheus.Labels) uint64 {
hash.Reset()
strBuf.Reset()
strBuf.WriteString(name)
hash.Write(strBuf.Bytes())
binary.BigEndian.PutUint64(intBuf, model.LabelsToSignature(labels))
hash.Write(intBuf)
return hash.Sum64()
}
type CounterContainer struct {
Elements map[uint64]prometheus.Counter
}
func NewCounterContainer() *CounterContainer {
return &CounterContainer{
Elements: make(map[uint64]prometheus.Counter),
}
}
func (c *CounterContainer) Get(metricName string, labels prometheus.Labels) prometheus.Counter {
hash := hashNameAndLabels(metricName, labels)
counter, ok := c.Elements[hash]
if !ok {
counter = prometheus.NewCounter(prometheus.CounterOpts{
Name: metricName,
Help: defaultHelp,
ConstLabels: labels,
})
c.Elements[hash] = counter
if err := prometheus.Register(counter); err != nil {
log.Fatalf(regErrF, metricName, err)
}
}
return counter
}
type GaugeContainer struct {
Elements map[uint64]prometheus.Gauge
}
func NewGaugeContainer() *GaugeContainer {
return &GaugeContainer{
Elements: make(map[uint64]prometheus.Gauge),
}
}
func (c *GaugeContainer) Get(metricName string, labels prometheus.Labels) prometheus.Gauge {
hash := hashNameAndLabels(metricName, labels)
gauge, ok := c.Elements[hash]
if !ok {
gauge = prometheus.NewGauge(prometheus.GaugeOpts{
Name: metricName,
Help: defaultHelp,
ConstLabels: labels,
})
c.Elements[hash] = gauge
if err := prometheus.Register(gauge); err != nil {
log.Fatalf(regErrF, metricName, err)
}
}
return gauge
}
type SummaryContainer struct {
Elements map[uint64]prometheus.Summary
}
func NewSummaryContainer() *SummaryContainer {
return &SummaryContainer{
Elements: make(map[uint64]prometheus.Summary),
}
}
func (c *SummaryContainer) Get(metricName string, labels prometheus.Labels) prometheus.Summary {
hash := hashNameAndLabels(metricName, labels)
summary, ok := c.Elements[hash]
if !ok {
summary = prometheus.NewSummary(
prometheus.SummaryOpts{
Name: metricName,
Help: defaultHelp,
ConstLabels: labels,
})
c.Elements[hash] = summary
if err := prometheus.Register(summary); err != nil {
log.Fatalf(regErrF, metricName, err)
}
}
return summary
}
type Event interface {
MetricName() string
Value() float64
}
type CounterEvent struct {
metricName string
value float64
}
func (c *CounterEvent) MetricName() string { return c.metricName }
func (c *CounterEvent) Value() float64 { return c.value }
type GaugeEvent struct {
metricName string
value float64
}
func (g *GaugeEvent) MetricName() string { return g.metricName }
func (g *GaugeEvent) Value() float64 { return g.value }
type TimerEvent struct {
metricName string
value float64
}
func (t *TimerEvent) MetricName() string { return t.metricName }
func (t *TimerEvent) Value() float64 { return t.value }
type Events []Event
type Bridge struct {
Counters *CounterContainer
Gauges *GaugeContainer
Summaries *SummaryContainer
mapper *metricMapper
}
func escapeMetricName(metricName string) string {
// If a metric starts with a digit, prepend an underscore.
if metricName[0] >= '0' && metricName[0] <= '9' {
metricName = "_" + metricName
}
// Replace all illegal metric chars with underscores.
metricName = illegalCharsRE.ReplaceAllString(metricName, "_")
return metricName
}
func (b *Bridge) Listen(e <-chan Events) {
for {
events := <-e
for _, event := range events {
metricName := ""
prometheusLabels := prometheus.Labels{}
labels, present := b.mapper.getMapping(event.MetricName())
if present {
metricName = labels["name"]
for label, value := range labels {
if label != "name" {
prometheusLabels[label] = value
}
}
} else {
metricName = escapeMetricName(event.MetricName())
}
switch event.(type) {
case *CounterEvent:
counter := b.Counters.Get(
metricName+"_counter",
prometheusLabels,
)
counter.Add(event.Value())
eventStats.WithLabelValues("counter").Inc()
case *GaugeEvent:
gauge := b.Gauges.Get(
metricName+"_gauge",
prometheusLabels,
)
gauge.Set(event.Value())
eventStats.WithLabelValues("gauge").Inc()
case *TimerEvent:
summary := b.Summaries.Get(
metricName+"_timer",
prometheusLabels,
)
summary.Observe(event.Value())
eventStats.WithLabelValues("timer").Inc()
default:
log.Println("Unsupported event type")
eventStats.WithLabelValues("illegal").Inc()
}
}
}
}
func NewBridge(mapper *metricMapper) *Bridge {
return &Bridge{
Counters: NewCounterContainer(),
Gauges: NewGaugeContainer(),
Summaries: NewSummaryContainer(),
mapper: mapper,
}
}
type StatsDListener struct {
conn *net.UDPConn
}
func buildEvent(statType, metric string, value float64) (Event, error) {
switch statType {
case "c":
return &CounterEvent{
metricName: metric,
value: float64(value),
}, nil
case "g":
return &GaugeEvent{
metricName: metric,
value: float64(value),
}, nil
case "ms":
return &TimerEvent{
metricName: metric,
value: float64(value),
}, nil
case "s":
return nil, fmt.Errorf("No support for StatsD sets")
default:
return nil, fmt.Errorf("Bad stat type %s", statType)
}
}
func (l *StatsDListener) Listen(e chan<- Events) {
// TODO: evaluate proper size according to MTU
var buf [512]byte
for {
n, _, err := l.conn.ReadFromUDP(buf[0:])
if err != nil {
log.Fatal(err)
}
l.handlePacket(buf[0:n], e)
}
}
func (l *StatsDListener) handlePacket(packet []byte, e chan<- Events) {
lines := strings.Split(string(packet), "\n")
events := Events{}
for _, line := range lines {
if line == "" {
continue
}
elements := strings.Split(line, ":")
if len(elements) < 2 {
networkStats.WithLabelValues("malformed_line").Inc()
log.Println("Bad line from StatsD:", line)
continue
}
metric := elements[0]
samples := elements[1:]
for _, sample := range samples {
components := strings.Split(sample, "|")
samplingFactor := 1.0
if len(components) < 2 || len(components) > 3 {
networkStats.WithLabelValues("malformed_component").Inc()
log.Println("Bad component on line:", line)
continue
}
valueStr, statType := components[0], components[1]
value, err := strconv.ParseFloat(valueStr, 64)
if err != nil {
log.Printf("Bad value %s on line: %s", valueStr, line)
networkStats.WithLabelValues("malformed_value").Inc()
continue
}
if len(components) == 3 {
if statType != "c" {
log.Println("Illegal sampling factor for non-counter metric on line", line)
networkStats.WithLabelValues("illegal_sample_factor").Inc()
}
samplingStr := components[2]
if samplingStr[0] != '@' {
log.Printf("Invalid sampling factor %s on line %s", samplingStr, line)
networkStats.WithLabelValues("invalid_sample_factor").Inc()
continue
}
samplingFactor, err = strconv.ParseFloat(samplingStr[1:], 64)
if err != nil {
log.Printf("Invalid sampling factor %s on line %s", samplingStr, line)
networkStats.WithLabelValues("invalid_sample_factor").Inc()
continue
}
if samplingFactor == 0 {
// This should never happen, but avoid division by zero if it does.
log.Printf("Invalid zero sampling factor %s on line %s, setting to 1", samplingStr, line)
samplingFactor = 1
}
value /= samplingFactor
}
event, err := buildEvent(statType, metric, value)
if err != nil {
log.Printf("Error building event on line %s: %s", line, err)
networkStats.WithLabelValues("illegal_event").Inc()
continue
}
events = append(events, event)
networkStats.WithLabelValues("legal").Inc()
}
}
e <- events
}