/
otel.go
174 lines (150 loc) · 5.19 KB
/
otel.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
package main
import (
"context"
"errors"
"fmt"
"go.opentelemetry.io/contrib/propagators/b3"
"go.opentelemetry.io/contrib/propagators/jaeger"
"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp"
"go.opentelemetry.io/otel/exporters/otlp/otlptrace"
"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
"os"
"strings"
"time"
"go.opentelemetry.io/otel"
"go.opentelemetry.io/otel/propagation"
"go.opentelemetry.io/otel/sdk/metric"
"go.opentelemetry.io/otel/sdk/resource"
"go.opentelemetry.io/otel/sdk/trace"
sdktrace "go.opentelemetry.io/otel/sdk/trace"
semconv "go.opentelemetry.io/otel/semconv/v1.21.0"
)
const OtelExporterOTLPEndpoints = "OTEL_EXPORTER_OTLP_ENDPOINT"
const OtelPropagators = "OTEL_PROPAGATORS"
// setupOTelSDK bootstraps the OpenTelemetry pipeline.
// If it does not return an error, make sure to call shutdown for proper cleanup.
func setupOTelSDK(ctx context.Context, serviceName, serviceVersion string) (shutdown func(context.Context) error, err error) {
var shutdownFuncs []func(context.Context) error
if os.Getenv(OtelExporterOTLPEndpoints) == "" {
fmt.Println("OTEL_EXPORTER_OTLP_ENDPOINT not provided, skip!!!")
return
}
// shutdown calls cleanup functions registered via shutdownFuncs.
// The errors from the calls are joined.
// Each registered cleanup will be invoked once.
shutdown = func(ctx context.Context) error {
var err error
for _, fn := range shutdownFuncs {
err = errors.Join(err, fn(ctx))
}
shutdownFuncs = nil
return err
}
// handleErr calls shutdown for cleanup and makes sure that all errors are returned.
handleErr := func(inErr error) {
err = errors.Join(inErr, shutdown(ctx))
}
// Set up resource.
res, err := newResource(serviceName, serviceVersion)
if err != nil {
handleErr(err)
return
}
// Set up propagator.
prop := newPropagator()
otel.SetTextMapPropagator(prop)
// Set up trace provider.
tracerProvider, err := newTraceProvider(res)
if err != nil {
handleErr(err)
return
}
shutdownFuncs = append(shutdownFuncs, tracerProvider.Shutdown)
otel.SetTracerProvider(tracerProvider)
// Set up meter provider.
meterProvider, err := newMeterProvider(res)
if err != nil {
handleErr(err)
return
}
shutdownFuncs = append(shutdownFuncs, meterProvider.Shutdown)
otel.SetMeterProvider(meterProvider)
return
}
func newResource(serviceName, serviceVersion string) (*resource.Resource, error) {
return resource.Merge(resource.Default(),
resource.NewWithAttributes(semconv.SchemaURL,
semconv.ServiceName(serviceName),
semconv.ServiceVersion(serviceVersion),
))
}
func newPropagator() propagation.TextMapPropagator {
propagatorString := os.Getenv(OtelPropagators)
var propagators []propagation.TextMapPropagator
if propagatorString != "" {
for _, p := range strings.Split(propagatorString, ",") {
switch p {
case "tracecontext":
propagators = append(propagators, propagation.TraceContext{})
case "b3":
propagators = append(propagators, b3.New(b3.WithInjectEncoding(b3.B3SingleHeader)))
case "b3multi":
propagators = append(propagators, b3.New(b3.WithInjectEncoding(b3.B3MultipleHeader)))
case "baggage":
propagators = append(propagators, propagation.Baggage{})
case "jaeger":
propagators = append(propagators, jaeger.Jaeger{})
}
}
}
if len(propagators) == 0 {
propagators = append(propagators, b3.New(b3.WithInjectEncoding(b3.B3SingleHeader)))
}
return propagation.NewCompositeTextMapPropagator(propagators...)
}
func newTraceProvider(res *resource.Resource) (*trace.TracerProvider, error) {
traceExporter, err := newTraceExporter()
if err != nil {
return nil, fmt.Errorf("failed to create trace provider: %w", err)
}
bsp := sdktrace.NewBatchSpanProcessor(traceExporter)
tracerProvider := sdktrace.NewTracerProvider(
sdktrace.WithSampler(sdktrace.AlwaysSample()),
sdktrace.WithResource(res),
sdktrace.WithSpanProcessor(bsp),
)
return tracerProvider, nil
}
func newTraceExporter() (*otlptrace.Exporter, error) {
ctx := context.Background()
ctx, cancel := context.WithTimeout(ctx, 5*time.Second)
defer cancel()
traceExporter, err := otlptracehttp.New(ctx, otlptracehttp.WithEndpoint(os.Getenv(OtelExporterOTLPEndpoints)), otlptracehttp.WithInsecure())
if err != nil {
return nil, fmt.Errorf("failed to create trace exporter: %w", err)
}
return traceExporter, nil
}
func newMeterProvider(res *resource.Resource) (*metric.MeterProvider, error) {
metricExporter, err := newMetricExporter()
if err != nil {
return nil, fmt.Errorf("failed to create meter provider: %w", err)
}
meterProvider := metric.NewMeterProvider(
metric.WithResource(res),
metric.WithReader(metric.NewPeriodicReader(metricExporter,
// Default is 1m. Set to 5s for demonstrative purposes.
metric.WithInterval(5*time.Second))),
)
return meterProvider, nil
}
func newMetricExporter() (*otlpmetrichttp.Exporter, error) {
ctx := context.Background()
ctx, cancel := context.WithTimeout(ctx, 5*time.Second)
defer cancel()
metricExporter, err := otlpmetrichttp.New(ctx, otlpmetrichttp.WithEndpoint(os.Getenv(OtelExporterOTLPEndpoints)), otlpmetrichttp.WithInsecure())
if err != nil {
return nil, fmt.Errorf("failed to create metrics exporter: %w", err)
}
return metricExporter, nil
}