bittorrent: implement nicer String methods for various types

bittorrent/bittorrent.go

@@ -4,6 +4,7 @@
 package bittorrent
 
 import (
+	"fmt"
 	"net"
 	"time"
 
@@ -26,7 +27,13 @@ func PeerIDFromBytes(b []byte) PeerID {
 	return PeerID(buf)
 }
 
+// String implements fmt.Stringer, returning the base16 encoded PeerID.
 func (p PeerID) String() string {
+	return fmt.Sprintf("%x", p[:])
+}
+
+// RawString returns a 20-byte string of the raw bytes of the ID.
+func (p PeerID) RawString() string {
 	return string(p[:])
 }
 
@@ -72,7 +79,13 @@ func InfoHashFromString(s string) InfoHash {
 	return InfoHash(buf)
 }
 
+// String implements fmt.Stringer, returning the base16 encoded InfoHash.
 func (i InfoHash) String() string {
+	return fmt.Sprintf("%x", i[:])
+}
+
+// RawString returns a 20-byte string of the raw bytes of the InfoHash.
+func (i InfoHash) RawString() string {
 	return string(i[:])
 }
 
@@ -212,6 +225,22 @@ type Peer struct {
 	Port uint16
 }
 
+// String implements fmt.Stringer to return a human-readable representation.
+// The string will have the format <PeerID>@[<IP>]:<port>, for example
+// "0102030405060708090a0b0c0d0e0f1011121314@[10.11.12.13]:1234"
+func (p Peer) String() string {
+	return fmt.Sprintf("%s@[%s]:%d", p.ID.String(), p.IP.String(), p.Port)
+}
+
+// LogFields renders the current peer as a set of Logrus fields.
+func (p Peer) LogFields() log.Fields {
+	return log.Fields{
+		"ID":   p.ID,
+		"IP":   p.IP,
+		"port": p.Port,
+	}
+}
+
 // Equal reports whether p and x are the same.
 func (p Peer) Equal(x Peer) bool { return p.EqualEndpoint(x) && p.ID == x.ID }
 

bittorrent/bittorrent_test.go

@@ -0,0 +1,59 @@
+package bittorrent
+
+import (
+	"fmt"
+	"net"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+var (
+	b        = []byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20}
+	expected = "0102030405060708090a0b0c0d0e0f1011121314"
+)
+
+var peerStringTestCases = []struct {
+	input    Peer
+	expected string
+}{
+	{
+		input: Peer{
+			ID: PeerIDFromBytes(b),
+			IP: IP{
+				IP:            net.IPv4(10, 11, 12, 1),
+				AddressFamily: IPv4,
+			},
+			Port: 1234,
+		},
+		expected: fmt.Sprintf("%s@[10.11.12.1]:1234", expected),
+	},
+	{
+		input: Peer{
+			ID: PeerIDFromBytes(b),
+			IP: IP{
+				IP:            net.ParseIP("2001:db8::ff00:42:8329"),
+				AddressFamily: IPv6,
+			},
+			Port: 1234,
+		},
+		expected: fmt.Sprintf("%s@[2001:db8::ff00:42:8329]:1234", expected),
+	},
+}
+
+func TestPeerID_String(t *testing.T) {
+	s := PeerIDFromBytes(b).String()
+	require.Equal(t, expected, s)
+}
+
+func TestInfoHash_String(t *testing.T) {
+	s := InfoHashFromBytes(b).String()
+	require.Equal(t, expected, s)
+}
+
+func TestPeer_String(t *testing.T) {
+	for _, c := range peerStringTestCases {
+		got := c.input.String()
+		require.Equal(t, c.expected, got)
+	}
+}