traefik/pkg/tracing/opentelemetry/opentelemetry.go
2024-01-08 09:10:06 +01:00

184 lines
6 KiB
Go

package opentelemetry
import (
"context"
"fmt"
"io"
"net"
"net/url"
"time"
"github.com/rs/zerolog/log"
"github.com/traefik/traefik/v3/pkg/types"
"github.com/traefik/traefik/v3/pkg/version"
"go.opentelemetry.io/otel"
"go.opentelemetry.io/otel/attribute"
"go.opentelemetry.io/otel/exporters/otlp/otlptrace"
"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc"
"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
"go.opentelemetry.io/otel/propagation"
"go.opentelemetry.io/otel/sdk/resource"
sdktrace "go.opentelemetry.io/otel/sdk/trace"
semconv "go.opentelemetry.io/otel/semconv/v1.21.0"
"go.opentelemetry.io/otel/trace"
"google.golang.org/grpc/credentials"
"google.golang.org/grpc/encoding/gzip"
)
// Config provides configuration settings for the open-telemetry tracer.
type Config struct {
GRPC *GRPC `description:"gRPC configuration for the OpenTelemetry collector." json:"grpc,omitempty" toml:"grpc,omitempty" yaml:"grpc,omitempty" export:"true"`
HTTP *HTTP `description:"HTTP configuration for the OpenTelemetry collector." json:"http,omitempty" toml:"http,omitempty" yaml:"http,omitempty" export:"true"`
}
// GRPC provides configuration settings for the gRPC open-telemetry tracer.
type GRPC struct {
Endpoint string `description:"Sets the gRPC endpoint (host:port) of the collector." json:"endpoint,omitempty" toml:"endpoint,omitempty" yaml:"endpoint,omitempty"`
Insecure bool `description:"Disables client transport security for the exporter." json:"insecure,omitempty" toml:"insecure,omitempty" yaml:"insecure,omitempty" export:"true"`
TLS *types.ClientTLS `description:"Defines client transport security parameters." json:"tls,omitempty" toml:"tls,omitempty" yaml:"tls,omitempty" export:"true"`
}
// SetDefaults sets the default values.
func (c *GRPC) SetDefaults() {
c.Endpoint = "localhost:4317"
}
// HTTP provides configuration settings for the HTTP open-telemetry tracer.
type HTTP struct {
Endpoint string `description:"Sets the HTTP endpoint (scheme://host:port/v1/traces) of the collector." json:"endpoint,omitempty" toml:"endpoint,omitempty" yaml:"endpoint,omitempty"`
TLS *types.ClientTLS `description:"Defines client transport security parameters." json:"tls,omitempty" toml:"tls,omitempty" yaml:"tls,omitempty" export:"true"`
}
// SetDefaults sets the default values.
func (c *HTTP) SetDefaults() {
c.Endpoint = "localhost:4318"
}
// Setup sets up the tracer.
func (c *Config) Setup(serviceName string, sampleRate float64, globalAttributes map[string]string, headers map[string]string) (trace.Tracer, io.Closer, error) {
var (
err error
exporter *otlptrace.Exporter
)
if c.GRPC != nil {
exporter, err = c.setupGRPCExporter(headers)
} else {
exporter, err = c.setupHTTPExporter(headers)
}
if err != nil {
return nil, nil, fmt.Errorf("setting up exporter: %w", err)
}
attr := []attribute.KeyValue{
semconv.ServiceNameKey.String(serviceName),
semconv.ServiceVersionKey.String(version.Version),
}
for k, v := range globalAttributes {
attr = append(attr, attribute.String(k, v))
}
res, err := resource.New(context.Background(),
resource.WithAttributes(attr...),
resource.WithFromEnv(),
resource.WithTelemetrySDK(),
resource.WithOSType(),
resource.WithProcessCommandArgs(),
)
if err != nil {
return nil, nil, fmt.Errorf("building resource: %w", err)
}
// Register the trace exporter with a TracerProvider, using a batch
// span processor to aggregate spans before export.
bsp := sdktrace.NewBatchSpanProcessor(exporter)
tracerProvider := sdktrace.NewTracerProvider(
sdktrace.WithSampler(sdktrace.TraceIDRatioBased(sampleRate)),
sdktrace.WithResource(res),
sdktrace.WithSpanProcessor(bsp),
)
otel.SetTracerProvider(tracerProvider)
otel.SetTextMapPropagator(propagation.TraceContext{})
log.Debug().Msg("OpenTelemetry tracer configured")
return tracerProvider.Tracer("github.com/traefik/traefik"), &tpCloser{provider: tracerProvider}, err
}
func (c *Config) setupHTTPExporter(headers map[string]string) (*otlptrace.Exporter, error) {
endpoint, err := url.Parse(c.HTTP.Endpoint)
if err != nil {
return nil, fmt.Errorf("invalid collector endpoint %q: %w", c.HTTP.Endpoint, err)
}
opts := []otlptracehttp.Option{
otlptracehttp.WithEndpoint(endpoint.Host),
otlptracehttp.WithHeaders(headers),
otlptracehttp.WithCompression(otlptracehttp.GzipCompression),
}
if endpoint.Scheme == "http" {
opts = append(opts, otlptracehttp.WithInsecure())
}
if endpoint.Path != "" {
opts = append(opts, otlptracehttp.WithURLPath(endpoint.Path))
}
if c.HTTP.TLS != nil {
tlsConfig, err := c.HTTP.TLS.CreateTLSConfig(context.Background())
if err != nil {
return nil, fmt.Errorf("creating TLS client config: %w", err)
}
opts = append(opts, otlptracehttp.WithTLSClientConfig(tlsConfig))
}
return otlptrace.New(context.Background(), otlptracehttp.NewClient(opts...))
}
func (c *Config) setupGRPCExporter(headers map[string]string) (*otlptrace.Exporter, error) {
host, port, err := net.SplitHostPort(c.GRPC.Endpoint)
if err != nil {
return nil, fmt.Errorf("invalid collector address %q: %w", c.GRPC.Endpoint, err)
}
opts := []otlptracegrpc.Option{
otlptracegrpc.WithEndpoint(fmt.Sprintf("%s:%s", host, port)),
otlptracegrpc.WithHeaders(headers),
otlptracegrpc.WithCompressor(gzip.Name),
}
if c.GRPC.Insecure {
opts = append(opts, otlptracegrpc.WithInsecure())
}
if c.GRPC.TLS != nil {
tlsConfig, err := c.GRPC.TLS.CreateTLSConfig(context.Background())
if err != nil {
return nil, fmt.Errorf("creating TLS client config: %w", err)
}
opts = append(opts, otlptracegrpc.WithTLSCredentials(credentials.NewTLS(tlsConfig)))
}
return otlptrace.New(context.Background(), otlptracegrpc.NewClient(opts...))
}
// tpCloser converts a TraceProvider into an io.Closer.
type tpCloser struct {
provider *sdktrace.TracerProvider
}
func (t *tpCloser) Close() error {
if t == nil {
return nil
}
ctx, cancel := context.WithDeadline(context.Background(), time.Now().Add(5*time.Second))
defer cancel()
return t.provider.Shutdown(ctx)
}