otel-proto.go

package main

import (
	"bytes"
	"fmt"
	"io"
	"net/http"
	"time"

	collectorpb "go.opentelemetry.io/proto/otlp/collector/trace/v1"
	commonpb "go.opentelemetry.io/proto/otlp/common/v1"
	resourcepb "go.opentelemetry.io/proto/otlp/resource/v1"
	tracepb "go.opentelemetry.io/proto/otlp/trace/v1"
	"google.golang.org/protobuf/encoding/protojson"
)

func main() {
	span := tracepb.Span{
		TraceId:           []byte("9890e50e34146fb0c3f371322fa98681"),
		SpanId:            []byte("53fc540cb095d5e2"),
		ParentSpanId:      []byte(""),
		Name:              "my-span",
		Kind:              *tracepb.Span_SPAN_KIND_CLIENT.Enum(),
		StartTimeUnixNano: uint64(time.Now().Add(-2 * time.Second).UnixNano()),
		EndTimeUnixNano:   uint64(time.Now().UnixNano()),
		Attributes: []*commonpb.KeyValue{
			{
				Key:   "span.kind",
				Value: &commonpb.AnyValue{Value: &commonpb.AnyValue_StringValue{StringValue: "client"}},
			},
		},
		Status: &tracepb.Status{
			Code:    0,
			Message: "OK",
		},
	}

	td := collectorpb.ExportTraceServiceRequest{
		ResourceSpans: []*tracepb.ResourceSpans{
			{
				Resource: &resourcepb.Resource{
					Attributes: []*commonpb.KeyValue{
						{
							Key:   "service.name",
							Value: &commonpb.AnyValue{Value: &commonpb.AnyValue_StringValue{StringValue: "my-service"}},
						},
					},
				},
				ScopeSpans: []*tracepb.ScopeSpans{
					{
						Scope: &commonpb.InstrumentationScope{
							Name: "my-scope",
						},
						Spans: []*tracepb.Span{
							&span,
						},
					},
				},
			},
		},
	}

	payload, err := protojson.Marshal(&td)
	if err != nil {
		panic(err)
	}

	req, err := http.NewRequest("POST", "http://localhost:4318/v1/traces", bytes.NewBuffer(payload))
	if err != nil {
		panic(err)
	}
	req.Header.Set("Content-Type", "application/json")

	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		panic(err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		panic(err)
	}
	fmt.Println(string(body))
	fmt.Println(resp.StatusCode)
}