Merge pull request #14 from libp2p/feat/p2paddr

Add func to construct /ipfs addrs from PeerInfo

peerinfo.go

@@ -31,12 +31,13 @@ func InfoFromP2pAddr(m ma.Multiaddr) (*PeerInfo, error) {
 		return nil, ErrInvalidAddr
 	}
 
-	ipfspart := parts[len(parts)-1] // last part
+	// TODO(lgierth): we shouldn't assume /ipfs is the last part
+	ipfspart := parts[len(parts)-1]
 	if ipfspart.Protocols()[0].Code != ma.P_IPFS {
 		return nil, ErrInvalidAddr
 	}
 
-	// make sure 'ipfs id' parses as a peer.ID
+	// make sure the /ipfs value parses as a peer.ID
 	peerIdParts := strings.Split(ipfspart.String(), "/")
 	peerIdStr := peerIdParts[len(peerIdParts)-1]
 	id, err := peer.IDB58Decode(peerIdStr)
@@ -44,12 +45,31 @@ func InfoFromP2pAddr(m ma.Multiaddr) (*PeerInfo, error) {
 		return nil, err
 	}
 
+	// we might have received just an /ipfs part, which means there's no addr.
+	var addrs []ma.Multiaddr
+	if len(parts) > 1 {
+		addrs = append(addrs, ma.Join(parts[:len(parts)-1]...))
+	}
+
 	return &PeerInfo{
 		ID:    id,
-		Addrs: []ma.Multiaddr{ma.Join(parts[:len(parts)-1]...)},
+		Addrs: addrs,
 	}, nil
 }
 
+func InfoToP2pAddrs(pi *PeerInfo) ([]ma.Multiaddr, error) {
+	addrs := []ma.Multiaddr{}
+	tpl := "/" + ma.ProtocolWithCode(ma.P_IPFS).Name + "/"
+	for _, addr := range pi.Addrs {
+		p2paddr, err := ma.NewMultiaddr(tpl + peer.IDB58Encode(pi.ID))
+		if err != nil {
+			return nil, err
+		}
+		addrs = append(addrs, addr.Encapsulate(p2paddr))
+	}
+	return addrs, nil
+}
+
 func (pi *PeerInfo) Loggable() map[string]interface{} {
 	return map[string]interface{}{
 		"peerID": pi.ID.Pretty(),

peerinfo_test.go

@@ -58,28 +58,92 @@ func TestPeerInfoMarshal(t *testing.T) {
 }
 
 func TestP2pAddrParsing(t *testing.T) {
-	a := mustAddr(t, "/ip4/1.2.3.4/tcp/4536")
 	id, err := peer.IDB58Decode("QmaCpDMGvV2BGHeYERUEnRQAwe3N8SzbUtfsmvsqQLuvuJ")
 	if err != nil {
-		t.Fatal(err)
+		t.Error(err)
 	}
+	addr := ma.StringCast("/ip4/1.2.3.4/tcp/4536")
+	p2paddr := ma.Join(addr, ma.StringCast("/ipfs/"+peer.IDB58Encode(id)))
 
-	p2pa := a.String() + "/ipfs/" + id.Pretty()
+	pinfo, err := InfoFromP2pAddr(p2paddr)
-	p2pma, err := ma.NewMultiaddr(p2pa)
 	if err != nil {
-		t.Fatal(err)
+		t.Error(err)
-	}
-
-	pinfo, err := InfoFromP2pAddr(p2pma)
-	if err != nil {
-		t.Fatal(err)
 	}
 
 	if pinfo.ID != id {
-		t.Fatal("didnt get expected peerID")
+		t.Fatalf("expected PeerID [%s], got [%s]", id, pinfo.ID)
 	}
 
-	if !a.Equal(pinfo.Addrs[0]) {
+	if len(pinfo.Addrs) != 1 {
-		t.Fatal("didnt get expected address")
+		t.Fatalf("expected 1 addr, got %d", len(pinfo.Addrs))
+	}
+
+	if !addr.Equal(pinfo.Addrs[0]) {
+		t.Fatalf("expected addr [%s], got [%s]", addr, pinfo.Addrs[0])
+	}
+
+	addr = ma.StringCast("/ipfs/" + peer.IDB58Encode(id))
+	pinfo, err = InfoFromP2pAddr(addr)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if pinfo.ID != id {
+		t.Fatalf("expected PeerID [%s], got [%s]", id, pinfo.ID)
+	}
+
+	if len(pinfo.Addrs) > 0 {
+		t.Fatalf("expected 0 addrs, got %d", len(pinfo.Addrs))
+	}
+
+	addr = ma.StringCast("/ip4/1.2.3.4/tcp/4536")
+	pinfo, err = InfoFromP2pAddr(addr)
+	if err == nil {
+		t.Fatalf("expected error, got none")
+	}
+
+	addr = ma.StringCast("/ip4/1.2.3.4/tcp/4536/http")
+	pinfo, err = InfoFromP2pAddr(addr)
+	if err == nil {
+		t.Fatalf("expected error, got none")
+	}
+}
+
+func TestP2pAddrConstruction(t *testing.T) {
+	id, err := peer.IDB58Decode("QmaCpDMGvV2BGHeYERUEnRQAwe3N8SzbUtfsmvsqQLuvuJ")
+	if err != nil {
+		t.Error(err)
+	}
+	addr := ma.StringCast("/ip4/1.2.3.4/tcp/4536")
+	p2paddr := ma.Join(addr, ma.StringCast("/ipfs/"+peer.IDB58Encode(id)))
+
+	pi := &PeerInfo{ID: id, Addrs: []ma.Multiaddr{addr}}
+	p2paddrs, err := InfoToP2pAddrs(pi)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if len(p2paddrs) != 1 {
+		t.Fatalf("expected 1 addr, got %d", len(p2paddrs))
+	}
+
+	if !p2paddr.Equal(p2paddrs[0]) {
+		t.Fatalf("expected [%s], got [%s]", p2paddr, p2paddrs[0])
+	}
+
+	pi = &PeerInfo{ID: id}
+	p2paddrs, err = InfoToP2pAddrs(pi)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if len(p2paddrs) > 0 {
+		t.Fatalf("expected 0 addrs, got %d", len(p2paddrs))
+	}
+
+	pi = &PeerInfo{Addrs: []ma.Multiaddr{ma.StringCast("/ip4/1.2.3.4/tcp/4536")}}
+	_, err = InfoToP2pAddrs(pi)
+	if err == nil {
+		t.Fatalf("expected error, got none")
 	}
 }