Improve cmd/tracker-announce output

cmd/tracker-announce/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"fmt"
 	"log"
 	"net/url"
 	"os"
@@ -8,8 +9,6 @@ import (
 	"sync"
 	"sync/atomic"
 
-	"github.com/davecgh/go-spew/spew"
-
 	"github.com/anacrolix/tagflag"
 
 	"github.com/anacrolix/torrent"
@@ -76,7 +75,7 @@ func doTracker(tURI string, ar tracker.AnnounceRequest) (hadError bool) {
 			log.Printf("error announcing to %q: %s", tURI, err)
 			continue
 		}
-		spew.Dump(resp)
+		fmt.Printf("response from %q: %+v\n", tURI, resp)
 	}
 	return
 }

tracker/peer.go

@@ -1,6 +1,7 @@
 package tracker
 
 import (
+	"fmt"
 	"net"
 
 	"github.com/anacrolix/dht/v2/krpc"
@@ -12,6 +13,15 @@ type Peer struct {
 	ID   []byte
 }
 
+func (p Peer) String() string {
+	loc := net.JoinHostPort(p.IP.String(), fmt.Sprintf("%d", p.Port))
+	if len(p.ID) != 0 {
+		return fmt.Sprintf("%x at %s", p.ID, loc)
+	} else {
+		return loc
+	}
+}
+
 // Set from the non-compact form in BEP 3.
 func (p *Peer) FromDictInterface(d map[string]interface{}) {
 	p.IP = net.ParseIP(d["ip"].(string))