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	Move github.com/openzipkin/zipkin-go-opentracing => github.com/openzipkin-contrib/zipkin-go-opentracing and run `go mod tidy` Fixes 3069 Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
		
			
				
	
	
		
			115 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			115 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| // Package trace implements OpenTracing-based tracing
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| package trace
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| 
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| import (
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| 	"context"
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| 	"fmt"
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| 	"sync"
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| 	"sync/atomic"
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| 
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| 	"github.com/coredns/coredns/plugin"
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| 	"github.com/coredns/coredns/plugin/metrics"
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| 	"github.com/coredns/coredns/plugin/pkg/dnstest"
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| 	"github.com/coredns/coredns/plugin/pkg/rcode"
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| 	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/opentracer"
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| 	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
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| 
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| 	// Plugin the trace package.
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| 	_ "github.com/coredns/coredns/plugin/pkg/trace"
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| 	"github.com/coredns/coredns/request"
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| 
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| 	"github.com/miekg/dns"
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| 	ot "github.com/opentracing/opentracing-go"
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| 	zipkin "github.com/openzipkin-contrib/zipkin-go-opentracing"
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| )
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| 
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| const (
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| 	tagName  = "coredns.io/name"
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| 	tagType  = "coredns.io/type"
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| 	tagRcode = "coredns.io/rcode"
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| )
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| 
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| type trace struct {
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| 	Next            plugin.Handler
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| 	Endpoint        string
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| 	EndpointType    string
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| 	tracer          ot.Tracer
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| 	serviceEndpoint string
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| 	serviceName     string
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| 	clientServer    bool
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| 	every           uint64
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| 	count           uint64
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| 	Once            sync.Once
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| }
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| 
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| func (t *trace) Tracer() ot.Tracer {
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| 	return t.tracer
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| }
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| 
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| // OnStartup sets up the tracer
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| func (t *trace) OnStartup() error {
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| 	var err error
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| 	t.Once.Do(func() {
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| 		switch t.EndpointType {
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| 		case "zipkin":
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| 			err = t.setupZipkin()
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| 		case "datadog":
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| 			tracer := opentracer.New(tracer.WithAgentAddr(t.Endpoint), tracer.WithServiceName(t.serviceName), tracer.WithDebugMode(true))
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| 			t.tracer = tracer
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| 		default:
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| 			err = fmt.Errorf("unknown endpoint type: %s", t.EndpointType)
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| 		}
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| 	})
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| 	return err
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| }
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| 
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| func (t *trace) setupZipkin() error {
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| 
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| 	collector, err := zipkin.NewHTTPCollector(t.Endpoint)
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| 	if err != nil {
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| 		return err
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| 	}
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| 
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| 	recorder := zipkin.NewRecorder(collector, false, t.serviceEndpoint, t.serviceName)
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| 	t.tracer, err = zipkin.NewTracer(recorder, zipkin.ClientServerSameSpan(t.clientServer))
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| 
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| 	return err
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| }
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| 
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| // Name implements the Handler interface.
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| func (t *trace) Name() string { return "trace" }
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| 
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| // ServeDNS implements the plugin.Handle interface.
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| func (t *trace) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
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| 	trace := false
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| 	if t.every > 0 {
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| 		queryNr := atomic.AddUint64(&t.count, 1)
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| 
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| 		if queryNr%t.every == 0 {
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| 			trace = true
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| 		}
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| 	}
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| 	span := ot.SpanFromContext(ctx)
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| 	if !trace || span != nil {
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| 		return plugin.NextOrFailure(t.Name(), t.Next, ctx, w, r)
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| 	}
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| 
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| 	req := request.Request{W: w, Req: r}
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| 	span = t.Tracer().StartSpan(spanName(ctx, req))
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| 	defer span.Finish()
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| 
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| 	rw := dnstest.NewRecorder(w)
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| 	ctx = ot.ContextWithSpan(ctx, span)
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| 	status, err := plugin.NextOrFailure(t.Name(), t.Next, ctx, rw, r)
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| 
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| 	span.SetTag(tagName, req.Name())
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| 	span.SetTag(tagType, req.Type())
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| 	span.SetTag(tagRcode, rcode.ToString(rw.Rcode))
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| 
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| 	return status, err
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| }
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| 
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| func spanName(ctx context.Context, req request.Request) string {
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| 	return "servedns:" + metrics.WithServer(ctx) + " " + req.Name()
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| }
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