move tracer implementation to its own file

trace.go

@@ -1,10 +1,6 @@
 package pubsub
 
 import (
-	"encoding/json"
-	"io"
-	"os"
-	"sync"
 	"time"
 
 	"github.com/libp2p/go-libp2p-core/peer"
@@ -18,74 +14,6 @@ type EventTracer interface {
 	Trace(evt interface{})
 }
 
-// JSONTracer is a tracer that writes events to a file, encoded in json.
-type JSONTracer struct {
-	w   io.WriteCloser
-	ch  chan struct{}
-	mx  sync.Mutex
-	buf []interface{}
-}
-
-// NewJsonTracer creates a new JSON tracer writing to file.
-func NewJSONTracer(file string) (*JSONTracer, error) {
-	return OpenJSONTracer(file, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0644)
-}
-
-// OpenJsonTracer creates a new JSON tracer, with explicit control of OpenFile flags and permissions.
-func OpenJSONTracer(file string, flags int, perm os.FileMode) (*JSONTracer, error) {
-	f, err := os.OpenFile(file, flags, perm)
-	if err != nil {
-		return nil, err
-	}
-
-	tr := &JSONTracer{w: f, ch: make(chan struct{}, 1)}
-	go tr.doWrite()
-
-	return tr, nil
-}
-
-func (t *JSONTracer) Trace(evt interface{}) {
-	t.mx.Lock()
-	t.buf = append(t.buf, evt)
-	t.mx.Unlock()
-
-	select {
-	case t.ch <- struct{}{}:
-	default:
-	}
-}
-
-func (t *JSONTracer) Close() {
-	close(t.ch)
-}
-
-func (t *JSONTracer) doWrite() {
-	var buf []interface{}
-	enc := json.NewEncoder(t.w)
-	for {
-		_, ok := <-t.ch
-
-		t.mx.Lock()
-		tmp := t.buf
-		t.buf = buf[:0]
-		buf = tmp
-		t.mx.Unlock()
-
-		for i, evt := range buf {
-			err := enc.Encode(evt)
-			if err != nil {
-				log.Errorf("error writing event trace: %s", err.Error())
-			}
-			buf[i] = nil
-		}
-
-		if !ok {
-			t.w.Close()
-			return
-		}
-	}
-}
-
 // pubsub tracer details
 type pubsubTracer struct {
 	tracer EventTracer

tracer.go

@@ -0,0 +1,76 @@
+package pubsub
+
+import (
+	"encoding/json"
+	"io"
+	"os"
+	"sync"
+)
+
+// JSONTracer is a tracer that writes events to a file, encoded in json.
+type JSONTracer struct {
+	w   io.WriteCloser
+	ch  chan struct{}
+	mx  sync.Mutex
+	buf []interface{}
+}
+
+// NewJsonTracer creates a new JSON tracer writing to file.
+func NewJSONTracer(file string) (*JSONTracer, error) {
+	return OpenJSONTracer(file, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0644)
+}
+
+// OpenJsonTracer creates a new JSON tracer, with explicit control of OpenFile flags and permissions.
+func OpenJSONTracer(file string, flags int, perm os.FileMode) (*JSONTracer, error) {
+	f, err := os.OpenFile(file, flags, perm)
+	if err != nil {
+		return nil, err
+	}
+
+	tr := &JSONTracer{w: f, ch: make(chan struct{}, 1)}
+	go tr.doWrite()
+
+	return tr, nil
+}
+
+func (t *JSONTracer) Trace(evt interface{}) {
+	t.mx.Lock()
+	t.buf = append(t.buf, evt)
+	t.mx.Unlock()
+
+	select {
+	case t.ch <- struct{}{}:
+	default:
+	}
+}
+
+func (t *JSONTracer) Close() {
+	close(t.ch)
+}
+
+func (t *JSONTracer) doWrite() {
+	var buf []interface{}
+	enc := json.NewEncoder(t.w)
+	for {
+		_, ok := <-t.ch
+
+		t.mx.Lock()
+		tmp := t.buf
+		t.buf = buf[:0]
+		buf = tmp
+		t.mx.Unlock()
+
+		for i, evt := range buf {
+			err := enc.Encode(evt)
+			if err != nil {
+				log.Errorf("error writing event trace: %s", err.Error())
+			}
+			buf[i] = nil
+		}
+
+		if !ok {
+			t.w.Close()
+			return
+		}
+	}
+}