whisper: unit test for libp2p Stream's Write + bugfix

whisper/whisperv6/libp2p_glue.go

@@ -74,9 +74,11 @@ func (stream *LibP2PStream) WriteMsg(msg p2p.Msg) error {
 	binary.LittleEndian.PutUint64(data[0:codeLength], msg.Code)
 	binary.LittleEndian.PutUint32(data[codeLength:codeLength+payloadSizeLength], msg.Size)
 
-	nbytes, err := msg.Payload.Read(data[8:])
+	nbytes, err := msg.Payload.Read(data[codeLength+payloadSizeLength:])
 	if (nbytes&0xFFFFFFFF) != nbytes || uint32(nbytes) != msg.Size {
 		return fmt.Errorf("Invalid size read in libp2p stream: read %d bytes, was expecting %d bytes", nbytes, msg.Size)
+	} else if err != nil {
+		return err
 	}
 
 	nbytes, err = stream.stream.Write(data)

whisper/whisperv6/libp2p_glue_test.go

@@ -0,0 +1,129 @@
+// Copyright 2018 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package whisperv6
+
+import (
+	"encoding/binary"
+	"context"
+	"bytes"
+	"testing"
+	"math/rand"
+
+	"github.com/ethereum/go-ethereum/p2p"
+	// libp2p "github.com/libp2p/go-libp2p"
+	host "github.com/libp2p/go-libp2p-host"
+	// crypto "github.com/libp2p/go-libp2p-crypto"
+	mocknet "github.com/libp2p/go-libp2p/p2p/net/mock"
+	testutil "github.com/libp2p/go-testutil"
+	inet "github.com/libp2p/go-libp2p-net"
+)
+
+const (
+	testProtocolId = "/whispertesting/6.1"
+)
+
+func createTestNetwork(t *testing.T, ctx context.Context, n int) []host.Host {
+	net := make([]host.Host, n)
+	mn := mocknet.New(ctx)
+
+	for i := 0; i < n; i++ {
+		a := testutil.RandLocalTCPAddress()
+		sk, _, err := testutil.RandTestKeyPair(512)
+		if err != nil {
+			t.Fatal(err)
+		}
+		h, err := mn.AddPeer(sk, a)
+		if err != nil {
+			t.Fatal(err)
+		}
+		n := h.Network()
+
+		net[i] = h
+
+		// Link to all previous hosts
+		for j := 0; j < i; j++ {
+			_, err = mn.LinkPeers(net[j].ID(), h.ID())
+			if err != nil {
+				t.Fatal(err)
+			}
+			if _, err := n.DialPeer(ctx, net[j].ID()); err != nil {
+				t.Error(err)
+			}
+		}
+	}
+
+	return net
+}
+
+func TestSimpleCode(t *testing.T) {
+	ctx := context.Background()
+	hosts := createTestNetwork(t, ctx, 2)
+
+	code := rand.Uint64()
+	size := rand.Uint32() % 512
+	payload := make([]byte, size)
+	n, err := rand.Read(payload)
+	if err != nil || uint32(n) != size {
+		t.Fatalf("Read %d random bytes instead of the expected %d, err: %v", n, size, err)
+	}
+
+	hosts[0].SetStreamHandler(testProtocolId, func (s inet.Stream) {
+		defer s.Close()
+
+		raw := make([]byte, size + codeLength + payloadSizeLength)
+		n, err = s.Read(raw)
+
+		if len(raw) != n || err != nil {
+			t.Fatalf("Error reading output of encoding (%d/%d bytes) %s", n, len(raw), err)
+		}
+		
+		c := binary.LittleEndian.Uint64(raw[:8])
+		if c != code {
+			t.Fatalf("Invalid code retreived %d, expected %d", c, code)
+		}
+		decodedSize := binary.LittleEndian.Uint32(raw[8:12])
+		if decodedSize != size {
+			t.Fatalf("Invalid size retreived %d, expected %d", decodedSize, size)
+		}
+
+		if !bytes.Equal(payload, raw[codeLength+payloadSizeLength:]) {
+			t.Fatalf("Encoded payload differ from source")
+		}
+	})
+	stream, err := hosts[1].NewStream(ctx, hosts[0].ID(), testProtocolId)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	msg := p2p.Msg{
+		Code:    code,
+		Size:    size,
+		Payload: bytes.NewReader(payload),
+	}
+
+	lps := LibP2PStream{
+		stream: stream,
+	}
+
+	err = lps.WriteMsg(msg)
+
+	if err != nil {
+		t.Fatalf("Error encoding a message to the stream: %s", err)
+	}
+
+	stream.Close()
+}