-
Notifications
You must be signed in to change notification settings - Fork 174
/
datadog.go
660 lines (586 loc) · 20.3 KB
/
datadog.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
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
package datadog
import (
"container/ring"
"context"
"errors"
"fmt"
"net/http"
"strings"
"sync"
"time"
"github.com/sirupsen/logrus"
"github.com/stripe/veneur/v14"
vhttp "github.com/stripe/veneur/v14/http"
"github.com/stripe/veneur/v14/protocol"
"github.com/stripe/veneur/v14/protocol/dogstatsd"
"github.com/stripe/veneur/v14/samplers"
"github.com/stripe/veneur/v14/sinks"
"github.com/stripe/veneur/v14/ssf"
"github.com/stripe/veneur/v14/trace"
"github.com/stripe/veneur/v14/trace/metrics"
"github.com/stripe/veneur/v14/util"
)
const datadogNameKey = "name"
const datadogResourceKey = "resource"
// At present Veneur has no way to differentiate between types. This could likely
// be changed to a tag conversion (e.g. tag type is removed and used for this value)
const datadogSpanType = "web"
// datadogSpanBufferSize is the default maximum number of spans that
// we can flush per flush-interval
const datadogSpanBufferSize = 1 << 14
type DatadogMetricSinkConfig struct {
APIKey string `yaml:"api_key"`
APIHostname string `yaml:"api_hostname"`
FlushMaxPerBody int `yaml:"flush_max_per_body"`
MetricNamePrefixDrops []string `yaml:"metric_name_prefix_drops"`
ExcludeTagsPrefixByPrefixMetric []struct {
MetricPrefix string `yaml:"metric_prefix"`
Tags []string `yaml:"tags"`
} `yaml:"exclude_tags_prefix_by_prefix_metric"`
}
type DatadogMetricSink struct {
HTTPClient *http.Client
APIKey string
DDHostname string
hostname string
flushMaxPerBody int
interval float64
traceClient *trace.Client
log *logrus.Entry
name string
metricNamePrefixDrops []string
excludedTags []string
excludeTagsPrefixByPrefixMetric map[string][]string
}
// ParseMetricConfig decodes the map config for a Datadog metric sink into a
// DatadogMetricSinkConfig struct.
func ParseMetricConfig(name string, config interface{}) (veneur.MetricSinkConfig, error) {
datadogConfig := DatadogMetricSinkConfig{}
err := util.DecodeConfig(name, config, &datadogConfig)
if err != nil {
return nil, err
}
return datadogConfig, nil
}
// CreateMetricSink creates a new Datadog sink for metrics. This function
// should match the signature of a value in veneur.MetricSinkTypes, and is
// intended to be passed into veneur.NewFromConfig to be called based on the
// provided configuration.
func CreateMetricSink(
server *veneur.Server, name string, logger *logrus.Entry,
config veneur.Config, sinkConfig veneur.MetricSinkConfig,
) (sinks.MetricSink, error) {
datadogConfig, ok := sinkConfig.(DatadogMetricSinkConfig)
if !ok {
return nil, errors.New("invalid sink config type")
}
excludeTagsPrefixByPrefixMetric := map[string][]string{}
for _, m := range datadogConfig.ExcludeTagsPrefixByPrefixMetric {
excludeTagsPrefixByPrefixMetric[m.MetricPrefix] = m.Tags
}
return &DatadogMetricSink{
HTTPClient: server.HTTPClient,
APIKey: datadogConfig.APIKey,
DDHostname: datadogConfig.APIHostname,
interval: server.Interval.Seconds(),
flushMaxPerBody: datadogConfig.FlushMaxPerBody,
hostname: config.Hostname,
name: name,
metricNamePrefixDrops: datadogConfig.MetricNamePrefixDrops,
excludeTagsPrefixByPrefixMetric: excludeTagsPrefixByPrefixMetric,
log: logger,
}, nil
}
// DDEvent represents the structure of datadog's undocumented /intake endpoint
type DDEvent struct {
Title string `json:"msg_title"`
Text string `json:"msg_text"`
Timestamp int64 `json:"timestamp,omitempty"` // represented as a unix epoch
Hostname string `json:"host,omitempty"`
Aggregation string `json:"aggregation_key,omitempty"`
Priority string `json:"priority,omitempty"`
Source string `json:"source_type_name,omitempty"`
AlertType string `json:"alert_type,omitempty"`
Tags []string `json:"tags,omitempty"`
}
// DDMetric is a data structure that represents the JSON that Datadog
// wants when posting to the API
type DDMetric struct {
Name string `json:"metric"`
Value [1][2]float64 `json:"points"`
Tags []string `json:"tags,omitempty"`
MetricType string `json:"type"`
Hostname string `json:"host,omitempty"`
DeviceName string `json:"device_name,omitempty"`
Interval int32 `json:"interval,omitempty"`
}
// DDServiceCheck is a representation of the service check.
type DDServiceCheck struct {
Name string `json:"check"`
Status int `json:"status"`
Hostname string `json:"host_name"`
Timestamp int64 `json:"timestamp,omitempty"` // represented as a unix epoch
Tags []string `json:"tags,omitempty"`
Message string `json:"message,omitempty"`
}
// Name returns the name of this sink.
func (dd *DatadogMetricSink) Name() string {
return dd.name
}
// Kind returns the kind of this sink
func (dd *DatadogMetricSink) Kind() string {
return "datadog"
}
// Start sets the sink up.
func (dd *DatadogMetricSink) Start(cl *trace.Client) error {
dd.traceClient = cl
return nil
}
// Flush sends metrics to Datadog
func (dd *DatadogMetricSink) Flush(ctx context.Context, interMetrics []samplers.InterMetric) (sinks.MetricFlushResult, error) {
span, _ := trace.StartSpanFromContext(ctx, "")
defer span.ClientFinish(dd.traceClient)
ddmetrics, checks := dd.finalizeMetrics(interMetrics)
if len(checks) != 0 {
// this endpoint is not documented to take an array... but it does
// another curious constraint of this endpoint is that it does not
// support "Content-Encoding: deflate"
err := vhttp.PostHelper(
context.TODO(), dd.HTTPClient, dd.traceClient, http.MethodPost,
fmt.Sprintf("%s/api/v1/check_run?api_key=%s", dd.DDHostname, dd.APIKey),
checks, "flush_checks", false, map[string]string{"sink": "datadog"},
dd.log)
if err == nil {
dd.log.WithField("checks", len(checks)).Info("Completed flushing service checks to Datadog")
} else {
dd.log.WithFields(logrus.Fields{
"checks": len(checks),
logrus.ErrorKey: err}).Warn("Error flushing checks to Datadog")
}
}
// break the metrics into chunks of approximately equal size, such that
// each chunk is less than the limit
// we compute the chunks using rounding-up integer division
workers := ((len(ddmetrics) - 1) / dd.flushMaxPerBody) + 1
chunkSize := ((len(ddmetrics) - 1) / workers) + 1
dd.log.WithField("workers", workers).Debug("Worker count chosen")
dd.log.WithField("chunkSize", chunkSize).Debug("Chunk size chosen")
var wg sync.WaitGroup
for i := 0; i < workers; i++ {
chunk := ddmetrics[i*chunkSize:]
if i < workers-1 {
// trim to chunk size unless this is the last one
chunk = chunk[:chunkSize]
}
wg.Add(1)
go dd.flushPart(span.Attach(ctx), chunk, &wg)
}
wg.Wait()
tags := map[string]string{"sink": dd.Name()}
span.Add(
ssf.Count(sinks.MetricKeyTotalMetricsFlushed, float32(len(ddmetrics)), tags),
)
dd.log.WithField("metrics", len(ddmetrics)).Info("flushed")
return sinks.MetricFlushResult{}, nil
}
// FlushOtherSamples serializes Events or Service Checks directly to datadog.
// May make 2 external calls to the datadog client.
func (dd *DatadogMetricSink) FlushOtherSamples(ctx context.Context, samples []ssf.SSFSample) {
events := []DDEvent{}
span, _ := trace.StartSpanFromContext(ctx, "")
defer span.ClientFinish(dd.traceClient)
// fill in the default hostname for packets that didn't set it
for _, sample := range samples {
if _, ok := sample.Tags[dogstatsd.EventIdentifierKey]; ok {
// This is an event!
ret := DDEvent{
Title: sample.Name,
Text: sample.Message,
Timestamp: sample.Timestamp,
Priority: "normal",
AlertType: "info",
}
// Defensively copy the tags that came in
tags := map[string]string{}
for k, v := range sample.Tags {
tags[k] = v
}
// Remove the tag that flagged this as an event
delete(tags, dogstatsd.EventIdentifierKey)
// The parser uses special tags to encode the fields for us from DogStatsD
// that don't fit into a normal SSF Sample. We'll hunt for each one and
// delete the tag if we find it.
if v, ok := tags[dogstatsd.EventAggregationKeyTagKey]; ok {
ret.Aggregation = v
delete(tags, dogstatsd.EventAggregationKeyTagKey)
}
if v, ok := tags[dogstatsd.EventPriorityTagKey]; ok {
ret.Priority = v
delete(tags, dogstatsd.EventPriorityTagKey)
}
if v, ok := tags[dogstatsd.EventSourceTypeTagKey]; ok {
ret.Source = v
delete(tags, dogstatsd.EventSourceTypeTagKey)
}
if v, ok := tags[dogstatsd.EventAlertTypeTagKey]; ok {
ret.AlertType = v
delete(tags, dogstatsd.EventAlertTypeTagKey)
}
if v, ok := tags[dogstatsd.EventHostnameTagKey]; ok {
ret.Hostname = v
delete(tags, dogstatsd.EventHostnameTagKey)
} else {
// Default hostname since there isn't one
ret.Hostname = dd.hostname
}
// Do our last bit of tag housekeeping
finalTags := []string{}
for k, v := range tags {
finalTags = append(finalTags, fmt.Sprintf("%s:%s", k, v))
}
ret.Tags = finalTags
events = append(events, ret)
} else {
dd.log.Warn("Received an SSF Sample that wasn't an event or service check, ack!")
}
}
if len(events) != 0 {
// this endpoint is not documented at all, its existence is only known from
// the official dd-agent
// we don't actually pass all the body keys that dd-agent passes here... but
// it still works
err := vhttp.PostHelper(
context.Background(), dd.HTTPClient, dd.traceClient, http.MethodPost,
fmt.Sprintf("%s/intake?api_key=%s", dd.DDHostname, dd.APIKey),
map[string]map[string][]DDEvent{
"events": {
"api": events,
},
}, "flush_events", true, map[string]string{"sink": "datadog"}, dd.log)
if err == nil {
dd.log.WithField("events", len(events)).Info("Completed flushing events to Datadog")
} else {
dd.log.WithFields(logrus.Fields{
"events": len(events),
logrus.ErrorKey: err}).Warn("Error flushing events to Datadog")
}
}
}
// SetExcludedTags sets the excluded tag names. Any tags with the
// provided key (name) will be excluded.
func (dd *DatadogMetricSink) SetExcludedTags(excludes []string) {
dd.excludedTags = excludes
}
func (dd *DatadogMetricSink) finalizeMetrics(metrics []samplers.InterMetric) ([]DDMetric, []DDServiceCheck) {
ddMetrics := make([]DDMetric, 0, len(metrics))
checks := []DDServiceCheck{}
METRICLOOP:
for _, m := range metrics {
for _, dropMetricPrefix := range dd.metricNamePrefixDrops {
if strings.HasPrefix(m.Name, dropMetricPrefix) {
continue METRICLOOP
}
}
// Defensively copy tags since we're gonna mutate it
tags := []string{}
// Prepare exclude tags by specific prefix metric
var excludeTagsPrefixByPrefixMetric []string
if len(dd.excludeTagsPrefixByPrefixMetric) > 0 {
for prefixMetric, tags := range dd.excludeTagsPrefixByPrefixMetric {
if strings.HasPrefix(m.Name, prefixMetric) {
excludeTagsPrefixByPrefixMetric = tags
break
}
}
}
var hostname, devicename string
// Let's look for "magic tags" that override metric fields host and device.
for _, tag := range m.Tags {
// This overrides hostname
if strings.HasPrefix(tag, "host:") {
// Override the hostname with the tag, trimming off the prefix.
hostname = tag[5:]
} else if strings.HasPrefix(tag, "device:") {
// Same as above, but device this time
devicename = tag[7:]
} else {
exclude := false
for i := range dd.excludedTags {
// access excluded tags by index to avoid a string copy
if strings.HasPrefix(tag, dd.excludedTags[i]) {
exclude = true
break
}
}
for i := range excludeTagsPrefixByPrefixMetric {
if strings.HasPrefix(tag, excludeTagsPrefixByPrefixMetric[i]) {
exclude = true
break
}
}
if !exclude {
tags = append(tags, tag)
}
}
}
if hostname == "" {
// No magic tag, set the hostname
hostname = dd.hostname
}
if m.Type == samplers.StatusMetric {
// This is a service check!
ret := DDServiceCheck{
Name: m.Name,
Message: m.Message,
Timestamp: m.Timestamp,
Tags: tags,
Status: int(m.Value),
Hostname: hostname,
}
// Do our last bit of tag housekeeping
checks = append(checks, ret)
continue
}
metricType := ""
value := m.Value
switch m.Type {
case samplers.CounterMetric:
// We convert counters into rates for Datadog
metricType = "rate"
value = m.Value / dd.interval
case samplers.GaugeMetric:
metricType = "gauge"
default:
dd.log.WithField("metric_type", m.Type).Warn("Encountered an unknown metric type")
continue
}
ddMetric := DDMetric{
Name: m.Name,
Value: [1][2]float64{
[2]float64{
float64(m.Timestamp), value,
},
},
Tags: tags,
MetricType: metricType,
Interval: int32(dd.interval),
Hostname: hostname,
DeviceName: devicename,
}
ddMetrics = append(ddMetrics, ddMetric)
}
return ddMetrics, checks
}
func (dd *DatadogMetricSink) flushPart(ctx context.Context, metricSlice []DDMetric, wg *sync.WaitGroup) {
defer wg.Done()
vhttp.PostHelper(ctx, dd.HTTPClient, dd.traceClient, http.MethodPost,
fmt.Sprintf("%s/api/v1/series?api_key=%s", dd.DDHostname, dd.APIKey),
map[string][]DDMetric{
"series": metricSlice,
}, "flush", true, map[string]string{"sink": "datadog"}, dd.log)
}
// DatadogTraceSpan represents a trace span as JSON for the
// Datadog tracing API.
type DatadogTraceSpan struct {
Duration int64 `json:"duration"`
Error int64 `json:"error"`
Meta map[string]string `json:"meta"`
Metrics map[string]float64 `json:"metrics"`
Name string `json:"name"`
ParentID int64 `json:"parent_id,omitempty"`
Resource string `json:"resource,omitempty"`
Service string `json:"service"`
SpanID int64 `json:"span_id"`
Start int64 `json:"start"`
TraceID int64 `json:"trace_id"`
Type string `json:"type"`
}
type DatadogSpanSinkConfig struct {
SpanBufferSize int `yaml:"datadog_span_buffer_size"`
TraceAPIAddress string `yaml:"datadog_trace_api_address"`
}
// DatadogSpanSink is a sink for sending spans to a Datadog trace agent.
type DatadogSpanSink struct {
HTTPClient *http.Client
buffer *ring.Ring
bufferSize int
mutex *sync.Mutex
traceAddress string
traceClient *trace.Client
log *logrus.Entry
name string
}
// ParseSpanConfig decodes the map config for a Datadog span sink into a
// DatadogSpanSinkConfig struct.
func ParseSpanConfig(name string, config interface{}) (veneur.SpanSinkConfig, error) {
datadogConfig := DatadogSpanSinkConfig{}
err := util.DecodeConfig(name, config, &datadogConfig)
if err != nil {
return nil, err
}
return datadogConfig, nil
}
// CreateSpanSink creates a new Datadog sink for spans. This function
// should match the signature of a value in veneur.SpanSinkTypes, and is
// intended to be passed into veneur.NewFromConfig to be called based on the
// provided configuration.
func CreateSpanSink(
server *veneur.Server, name string, logger *logrus.Entry,
config veneur.Config, sinkConfig veneur.SpanSinkConfig,
) (sinks.SpanSink, error) {
datadogConfig, ok := sinkConfig.(DatadogSpanSinkConfig)
if !ok {
return nil, errors.New("invalid sink config type")
}
bufferSize := datadogConfig.SpanBufferSize
if bufferSize == 0 {
bufferSize = datadogSpanBufferSize
}
return &DatadogSpanSink{
HTTPClient: server.HTTPClient,
bufferSize: bufferSize,
buffer: ring.New(bufferSize),
mutex: &sync.Mutex{},
traceAddress: datadogConfig.TraceAPIAddress,
log: logger,
name: name,
}, nil
}
// Name returns the name of this sink.
func (dd *DatadogSpanSink) Name() string {
return dd.name
}
// Start performs final adjustments on the sink.
func (dd *DatadogSpanSink) Start(cl *trace.Client) error {
dd.traceClient = cl
return nil
}
// Ingest takes the span and adds it to the ringbuffer.
func (dd *DatadogSpanSink) Ingest(span *ssf.SSFSpan) error {
if err := protocol.ValidateTrace(span); err != nil {
return err
}
dd.mutex.Lock()
defer dd.mutex.Unlock()
dd.buffer.Value = span
dd.buffer = dd.buffer.Next()
return nil
}
// Flush signals the sink to send it's spans to their destination. For this
// sync it means we'll be making an HTTP request to send them along. We assume
// it's beneficial to performance to defer these until the normal 10s flush.
func (dd *DatadogSpanSink) Flush() {
samples := &ssf.Samples{}
defer metrics.Report(dd.traceClient, samples)
dd.mutex.Lock()
flushStart := time.Now()
ssfSpans := make([]*ssf.SSFSpan, 0, dd.buffer.Len())
dd.buffer.Do(func(t interface{}) {
const tooEarly = 1497
const tooLate = 1497629343000000
if t != nil {
ssfSpan, ok := t.(*ssf.SSFSpan)
if !ok {
dd.log.Error("Got an unknown object in tracing ring!")
dd.mutex.Unlock()
// We'll just skip this one so we don't poison pill or anything.
return
}
var timeErr string
tags := map[string]string{} // TODO: tag as dd?
if ssfSpan.StartTimestamp < tooEarly {
tags["type"] = "tooEarly"
}
if ssfSpan.StartTimestamp > tooLate {
tags["type"] = "tooLate"
}
if timeErr != "" {
samples.Add(ssf.Count("worker.trace.sink.timestamp_error", 1, tags))
}
ssfSpans = append(ssfSpans, ssfSpan)
}
})
// Reset the ring.
dd.buffer = ring.New(dd.bufferSize)
// We're done manipulating stuff, let Ingest loose again.
dd.mutex.Unlock()
serviceCount := make(map[string]int64)
// Datadog wants the spans for each trace in an array, so make a map.
traceMap := map[int64][]*DatadogTraceSpan{}
// Convert the SSFSpans into Datadog Spans
for _, span := range ssfSpans {
// -1 is a canonical way of passing in invalid info in Go
// so we should support that too
parentID := span.ParentId
// check if this is the root span
if parentID <= 0 {
// we need parentId to be zero for json:omitempty to work
parentID = 0
}
tags := map[string]string{}
// Get the span's existing tags
for k, v := range span.Tags {
tags[k] = v
}
resource := span.Tags[datadogResourceKey]
if resource == "" {
resource = "unknown"
}
delete(tags, datadogResourceKey)
name := span.Name
if name == "" {
name = "unknown"
}
var errorCode int64
if span.Error {
errorCode = 2
}
ddspan := &DatadogTraceSpan{
TraceID: span.TraceId,
SpanID: span.Id,
ParentID: parentID,
Service: span.Service,
Name: name,
Resource: resource,
Start: span.StartTimestamp,
Duration: span.EndTimestamp - span.StartTimestamp,
Type: datadogSpanType,
Error: errorCode,
Meta: tags,
}
serviceCount[span.Service]++
if _, ok := traceMap[span.TraceId]; !ok {
traceMap[span.TraceId] = []*DatadogTraceSpan{}
}
traceMap[span.TraceId] = append(traceMap[span.TraceId], ddspan)
}
// Smush the spans into a two-dimensional array now that they are grouped by trace id.
finalTraces := make([][]*DatadogTraceSpan, len(traceMap))
idx := 0
for _, val := range traceMap {
finalTraces[idx] = val
idx++
}
if len(finalTraces) != 0 {
// this endpoint is not documented to take an array... but it does
// another curious constraint of this endpoint is that it does not
// support "Content-Encoding: deflate"
err := vhttp.PostHelper(
context.TODO(), dd.HTTPClient, dd.traceClient, http.MethodPut,
fmt.Sprintf("%s/v0.3/traces", dd.traceAddress), finalTraces,
"flush_traces", false, map[string]string{"sink": "datadog"}, dd.log)
if err == nil {
dd.log.WithField("traces", len(finalTraces)).Info("Completed flushing traces to Datadog")
} else {
dd.log.WithFields(logrus.Fields{
"traces": len(finalTraces),
logrus.ErrorKey: err}).Warn("Error flushing traces to Datadog")
}
for service, count := range serviceCount {
samples.Add(ssf.Count(sinks.MetricKeyTotalSpansFlushed, float32(count), map[string]string{"sink": dd.Name(), "service": service}))
}
samples.Add(ssf.Timing(sinks.MetricKeySpanFlushDuration, time.Since(flushStart), time.Nanosecond, map[string]string{"sink": dd.Name()}))
} else {
dd.log.Info("No traces to flush to Datadog, skipping.")
}
}