main.go

package main

import (
	"context"
	"flag"
	"fmt"
	"log"
	"net/http"
	"os"
	"strconv"

	"go.opentelemetry.io/otel"
	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace"
	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"

	otel_trace "go.opentelemetry.io/otel/trace"
	ddotel "gopkg.in/DataDog/dd-trace-go.v1/ddtrace/opentelemetry"
)

type apmClientServer struct {
	spans        map[uint64]tracer.Span
	spanContexts map[uint64]ddtrace.SpanContext
	otelSpans    map[uint64]spanContext
	tp           *ddotel.TracerProvider
	tracer       otel_trace.Tracer
}

type spanContext struct {
	span otel_trace.Span
	ctx  context.Context
}

func newServer() *apmClientServer {
	s := &apmClientServer{
		spans:        make(map[uint64]tracer.Span),
		spanContexts: make(map[uint64]ddtrace.SpanContext),
		otelSpans:    make(map[uint64]spanContext),
	}
	s.tp = ddotel.NewTracerProvider()
	otel.SetTracerProvider(s.tp)
	return s
}

func main() {
	flag.Parse()
	defer func() {
		if err := recover(); err != nil {
			log.Print("encountered unexpected panic", err)
		}
	}()
	port, err := strconv.Atoi(os.Getenv("APM_TEST_CLIENT_SERVER_PORT"))
	if err != nil {
		log.Fatalf("failed to convert port to integer: %v", err)
	}
	s := newServer()

	// dd-trace endpoints
	http.HandleFunc("/trace/span/start", s.startSpanHandler)
	http.HandleFunc("/trace/span/flush", s.flushSpansHandler)
	http.HandleFunc("/trace/stats/flush", s.flushStatsHandler)
	http.HandleFunc("/trace/span/set_meta", s.spanSetMetaHandler)
	http.HandleFunc("/trace/span/finish", s.finishSpanHandler)
	http.HandleFunc("/trace/span/set_metric", s.spanSetMetricHandler)
	http.HandleFunc("/trace/span/inject_headers", s.injectHeadersHandler)
	http.HandleFunc("/trace/span/extract_headers", s.extractHeadersHandler)
	http.HandleFunc("/trace/span/error", s.spanSetErrorHandler)
	http.HandleFunc("/trace/config", s.getTraceConfigHandler)

	// otel-api endpoints:
	http.HandleFunc("/trace/otel/start_span", s.otelStartSpanHandler)
	http.HandleFunc("/trace/otel/end_span", s.otelEndSpanHandler)
	http.HandleFunc("/trace/otel/set_attributes", s.otelSetAttributesHandler)
	http.HandleFunc("/trace/otel/set_name", s.otelSetNameHandler)
	http.HandleFunc("/trace/otel/flush", s.otelFlushSpansHandler)
	http.HandleFunc("/trace/otel/is_recording", s.otelIsRecordingHandler)
	http.HandleFunc("/trace/otel/span_context", s.otelSpanContextHandler)
	http.HandleFunc("/trace/otel/add_event", s.otelAddEventHandler)
	http.HandleFunc("/trace/otel/set_status", s.otelSetStatusHandler)

	err = http.ListenAndServe(fmt.Sprintf(":%d", port), nil)
	if err != nil {
		log.Fatalf("failed to listen: %v", err)
	}
	log.Printf("server listening at %v", fmt.Sprintf("0.0.0.0:%d", port))
}