log(bitswap) add bitswap loggable

exchange/bitswap/bitswap.go

@@ -409,6 +409,7 @@ func (bs *bitswap) ReceiveError(err error) {
 // send strives to ensure that accounting is always performed when a message is
 // sent
 func (bs *bitswap) send(ctx context.Context, p peer.ID, m bsmsg.BitSwapMessage) error {
+	defer log.EventBegin(ctx, "sendMessage", p, m).Done()
 	if err := bs.network.SendMessage(ctx, p, m); err != nil {
 		return errors.Wrap(err)
 	}

exchange/bitswap/message/message.go

@@ -39,6 +39,8 @@ type BitSwapMessage interface {
 
 	AddBlock(*blocks.Block)
 	Exportable
+
+	Loggable() map[string]interface{}
 }
 
 type Exportable interface {
@@ -170,3 +172,9 @@ func (m *impl) ToNet(w io.Writer) error {
 	}
 	return nil
 }
+
+func (m *impl) Loggable() map[string]interface{} {
+	return map[string]interface{}{
+		"wantlist": m.wantlist,
+	}
+}