// This example demonstrates the basic process for initializing and creating an
// outbound peer. Peers negotiate by exchanging version and verack messages.
// For demonstration, a simple handler for version message is attached to the
// peer.
func Example_newOutboundPeer() {
// Ordinarily this will not be needed since the outbound peer will be
// connecting to a remote peer, however, since this example is executed
// and tested, a mock remote peer is needed to listen for the outbound
// peer.
if err := mockRemotePeer(); err != nil {
fmt.Printf("mockRemotePeer: unexpected error %v\n", err)
return
}
// Create an outbound peer that is configured to act as a simnet node
// that offers no services and has listeners for the version and verack
// messages. The verack listener is used here to signal the code below
// when the handshake has been finished by signalling a channel.
verack := make(chan struct{})
peerCfg := &peer.Config{
UserAgentName: "peer", // User agent name to advertise.
UserAgentVersion: "1.0.0", // User agent version to advertise.
ChainParams: &chaincfg.SimNetParams,
Services: 0,
Listeners: peer.MessageListeners{
OnVersion: func(p *peer.Peer, msg *wire.MsgVersion) {
fmt.Println("outbound: received version")
},
OnVerAck: func(p *peer.Peer, msg *wire.MsgVerAck) {
verack <- struct{}{}
},
},
}
p, err := peer.NewOutboundPeer(peerCfg, "127.0.0.1:18555")
if err != nil {
fmt.Printf("NewOutboundPeer: error %v\n", err)
return
}
// Establish the connection to the peer address and mark it connected.
conn, err := net.Dial("tcp", p.Addr())
if err != nil {
fmt.Printf("net.Dial: error %v\n", err)
return
}
if err := p.Connect(conn); err != nil {
fmt.Printf("Connect: error %v\n", err)
return
}
// Wait for the verack message or timeout in case of failure.
select {
case <-verack:
case <-time.After(time.Second * 1):
fmt.Printf("Example_peerConnection: verack timeout")
}
// Shutdown the peer.
p.Shutdown()
// Output:
// outbound: received version
}
// TestPeerListeners tests that the peer listeners are called as expected.
func TestPeerListeners(t *testing.T) {
verack := make(chan struct{}, 1)
ok := make(chan wire.Message, 20)
peerCfg := &peer.Config{
Listeners: peer.MessageListeners{
OnGetAddr: func(p *peer.Peer, msg *wire.MsgGetAddr) {
ok <- msg
},
OnAddr: func(p *peer.Peer, msg *wire.MsgAddr) {
ok <- msg
},
OnPing: func(p *peer.Peer, msg *wire.MsgPing) {
ok <- msg
},
OnPong: func(p *peer.Peer, msg *wire.MsgPong) {
ok <- msg
},
OnAlert: func(p *peer.Peer, msg *wire.MsgAlert) {
ok <- msg
},
OnMemPool: func(p *peer.Peer, msg *wire.MsgMemPool) {
ok <- msg
},
OnTx: func(p *peer.Peer, msg *wire.MsgTx) {
ok <- msg
},
OnBlock: func(p *peer.Peer, msg *wire.MsgBlock, buf []byte) {
ok <- msg
},
OnInv: func(p *peer.Peer, msg *wire.MsgInv) {
ok <- msg
},
OnHeaders: func(p *peer.Peer, msg *wire.MsgHeaders) {
ok <- msg
},
OnNotFound: func(p *peer.Peer, msg *wire.MsgNotFound) {
ok <- msg
},
OnGetData: func(p *peer.Peer, msg *wire.MsgGetData) {
ok <- msg
},
OnGetBlocks: func(p *peer.Peer, msg *wire.MsgGetBlocks) {
ok <- msg
},
OnGetHeaders: func(p *peer.Peer, msg *wire.MsgGetHeaders) {
ok <- msg
},
OnFilterAdd: func(p *peer.Peer, msg *wire.MsgFilterAdd) {
ok <- msg
},
OnFilterClear: func(p *peer.Peer, msg *wire.MsgFilterClear) {
ok <- msg
},
OnFilterLoad: func(p *peer.Peer, msg *wire.MsgFilterLoad) {
ok <- msg
},
OnMerkleBlock: func(p *peer.Peer, msg *wire.MsgMerkleBlock) {
ok <- msg
},
OnVersion: func(p *peer.Peer, msg *wire.MsgVersion) {
ok <- msg
},
OnVerAck: func(p *peer.Peer, msg *wire.MsgVerAck) {
verack <- struct{}{}
},
OnReject: func(p *peer.Peer, msg *wire.MsgReject) {
ok <- msg
},
OnSendHeaders: func(p *peer.Peer, msg *wire.MsgSendHeaders) {
ok <- msg
},
},
UserAgentName: "peer",
UserAgentVersion: "1.0",
ChainParams: &chaincfg.MainNetParams,
Services: wire.SFNodeBloom,
}
inConn, outConn := pipe(
&conn{raddr: "10.0.0.1:8333"},
&conn{raddr: "10.0.0.2:8333"},
)
inPeer := peer.NewInboundPeer(peerCfg)
inPeer.Connect(inConn)
peerCfg.Listeners = peer.MessageListeners{
OnVerAck: func(p *peer.Peer, msg *wire.MsgVerAck) {
verack <- struct{}{}
},
}
outPeer, err := peer.NewOutboundPeer(peerCfg, "10.0.0.1:8333")
if err != nil {
t.Errorf("NewOutboundPeer: unexpected err %v\n", err)
return
}
outPeer.Connect(outConn)
for i := 0; i < 2; i++ {
select {
case <-verack:
case <-time.After(time.Second * 1):
t.Errorf("TestPeerListeners: verack timeout\n")
return
}
}
tests := []struct {
listener string
msg wire.Message
}{
{
"OnGetAddr",
wire.NewMsgGetAddr(),
},
{
"OnAddr",
wire.NewMsgAddr(),
},
{
"OnPing",
wire.NewMsgPing(42),
},
{
"OnPong",
wire.NewMsgPong(42),
},
{
"OnAlert",
wire.NewMsgAlert([]byte("payload"), []byte("signature")),
},
{
"OnMemPool",
wire.NewMsgMemPool(),
},
{
"OnTx",
wire.NewMsgTx(),
},
{
"OnBlock",
wire.NewMsgBlock(wire.NewBlockHeader(0, &chainhash.Hash{},
&chainhash.Hash{}, &chainhash.Hash{}, 1, [6]byte{},
1, 1, 1, 1, 1, 1, 1, 1, 1, [32]byte{},
binary.LittleEndian.Uint32([]byte{0xb0, 0x1d, 0xfa, 0xce}))),
},
{
"OnInv",
wire.NewMsgInv(),
},
{
"OnHeaders",
wire.NewMsgHeaders(),
},
{
"OnNotFound",
wire.NewMsgNotFound(),
},
{
"OnGetData",
wire.NewMsgGetData(),
},
{
"OnGetBlocks",
wire.NewMsgGetBlocks(&chainhash.Hash{}),
},
{
"OnGetHeaders",
wire.NewMsgGetHeaders(),
},
{
"OnFilterAdd",
wire.NewMsgFilterAdd([]byte{0x01}),
},
{
"OnFilterClear",
wire.NewMsgFilterClear(),
},
{
"OnFilterLoad",
wire.NewMsgFilterLoad([]byte{0x01}, 10, 0, wire.BloomUpdateNone),
},
{
"OnMerkleBlock",
wire.NewMsgMerkleBlock(wire.NewBlockHeader(0,
&chainhash.Hash{}, &chainhash.Hash{},
&chainhash.Hash{}, 1, [6]byte{},
1, 1, 1, 1, 1, 1, 1, 1, 1, [32]byte{},
binary.LittleEndian.Uint32([]byte{0xb0, 0x1d, 0xfa, 0xce}))),
},
// only one version message is allowed
// only one verack message is allowed
{
"OnReject",
wire.NewMsgReject("block", wire.RejectDuplicate, "dupe block"),
},
{
"OnSendHeaders",
wire.NewMsgSendHeaders(),
},
}
t.Logf("Running %d tests", len(tests))
for _, test := range tests {
// Queue the test message
outPeer.QueueMessage(test.msg, nil)
select {
case <-ok:
case <-time.After(time.Second * 1):
t.Errorf("TestPeerListeners: %s timeout", test.listener)
return
}
}
inPeer.Disconnect()
outPeer.Disconnect()
}
// TestOutboundPeer tests that the outbound peer works as expected.
func TestOutboundPeer(t *testing.T) {
peerCfg := &peer.Config{
NewestBlock: func() (*chainhash.Hash, int64, error) {
return nil, 0, errors.New("newest block not found")
},
UserAgentName: "peer",
UserAgentVersion: "1.0",
ChainParams: &chaincfg.MainNetParams,
Services: 0,
}
r, w := io.Pipe()
c := &conn{raddr: "10.0.0.1:8333", Writer: w, Reader: r}
p, err := peer.NewOutboundPeer(peerCfg, "10.0.0.1:8333")
if err != nil {
t.Errorf("NewOutboundPeer: unexpected err - %v\n", err)
return
}
// Test trying to connect twice.
p.Connect(c)
p.Connect(c)
disconnected := make(chan struct{})
go func() {
p.WaitForDisconnect()
disconnected <- struct{}{}
}()
select {
case <-disconnected:
close(disconnected)
case <-time.After(time.Second):
t.Fatal("Peer did not automatically disconnect.")
}
if p.Connected() {
t.Fatalf("Should not be connected as NewestBlock produces error.")
}
// Test Queue Inv
fakeBlockHash := &chainhash.Hash{0: 0x00, 1: 0x01}
fakeInv := wire.NewInvVect(wire.InvTypeBlock, fakeBlockHash)
// Should be noops as the peer could not connect.
p.QueueInventory(fakeInv)
p.AddKnownInventory(fakeInv)
p.QueueInventory(fakeInv)
fakeMsg := wire.NewMsgVerAck()
p.QueueMessage(fakeMsg, nil)
done := make(chan struct{})
p.QueueMessage(fakeMsg, done)
<-done
p.Disconnect()
// Test NewestBlock
var newestBlock = func() (*chainhash.Hash, int64, error) {
hashStr := "14a0810ac680a3eb3f82edc878cea25ec41d6b790744e5daeef"
hash, err := chainhash.NewHashFromStr(hashStr)
if err != nil {
return nil, 0, err
}
return hash, 234439, nil
}
peerCfg.NewestBlock = newestBlock
r1, w1 := io.Pipe()
c1 := &conn{raddr: "10.0.0.1:8333", Writer: w1, Reader: r1}
p1, err := peer.NewOutboundPeer(peerCfg, "10.0.0.1:8333")
if err != nil {
t.Errorf("NewOutboundPeer: unexpected err - %v\n", err)
return
}
p1.Connect(c1)
// Test update latest block
latestBlockSha, err := chainhash.NewHashFromStr("1a63f9cdff1752e6375c8c76e543a71d239e1a2e5c6db1aa679")
if err != nil {
t.Errorf("NewShaHashFromStr: unexpected err %v\n", err)
return
}
p1.UpdateLastAnnouncedBlock(latestBlockSha)
p1.UpdateLastBlockHeight(234440)
if p1.LastAnnouncedBlock() != latestBlockSha {
t.Errorf("LastAnnouncedBlock: wrong block - got %v, want %v",
p1.LastAnnouncedBlock(), latestBlockSha)
return
}
// Test Queue Inv after connection
p1.QueueInventory(fakeInv)
p1.Disconnect()
// Test testnet
peerCfg.ChainParams = &chaincfg.TestNetParams
peerCfg.Services = wire.SFNodeBloom
r2, w2 := io.Pipe()
c2 := &conn{raddr: "10.0.0.1:8333", Writer: w2, Reader: r2}
p2, err := peer.NewOutboundPeer(peerCfg, "10.0.0.1:8333")
if err != nil {
t.Errorf("NewOutboundPeer: unexpected err - %v\n", err)
return
}
p2.Connect(c2)
// Test PushXXX
var addrs []*wire.NetAddress
for i := 0; i < 5; i++ {
na := wire.NetAddress{}
addrs = append(addrs, &na)
}
if _, err := p2.PushAddrMsg(addrs); err != nil {
t.Errorf("PushAddrMsg: unexpected err %v\n", err)
return
}
if err := p2.PushGetBlocksMsg(nil, &chainhash.Hash{}); err != nil {
t.Errorf("PushGetBlocksMsg: unexpected err %v\n", err)
return
}
if err := p2.PushGetHeadersMsg(nil, &chainhash.Hash{}); err != nil {
t.Errorf("PushGetHeadersMsg: unexpected err %v\n", err)
return
}
p2.PushRejectMsg("block", wire.RejectMalformed, "malformed", nil, false)
p2.PushRejectMsg("block", wire.RejectInvalid, "invalid", nil, false)
// Test Queue Messages
p2.QueueMessage(wire.NewMsgGetAddr(), nil)
p2.QueueMessage(wire.NewMsgPing(1), nil)
p2.QueueMessage(wire.NewMsgMemPool(), nil)
p2.QueueMessage(wire.NewMsgGetData(), nil)
p2.QueueMessage(wire.NewMsgGetHeaders(), nil)
p2.Disconnect()
}
// TestPeerConnection tests connection between inbound and outbound peers.
func TestPeerConnection(t *testing.T) {
verack := make(chan struct{})
peerCfg := &peer.Config{
Listeners: peer.MessageListeners{
OnVerAck: func(p *peer.Peer, msg *wire.MsgVerAck) {
verack <- struct{}{}
},
OnWrite: func(p *peer.Peer, bytesWritten int, msg wire.Message,
err error) {
if _, ok := msg.(*wire.MsgVerAck); ok {
verack <- struct{}{}
}
},
},
UserAgentName: "peer",
UserAgentVersion: "1.0",
ChainParams: &chaincfg.MainNetParams,
Services: 0,
}
wantStats := peerStats{
wantUserAgent: wire.DefaultUserAgent + "peer:1.0/",
wantServices: 0,
wantProtocolVersion: peer.MaxProtocolVersion,
wantConnected: true,
wantVersionKnown: true,
wantVerAckReceived: true,
wantLastPingTime: time.Time{},
wantLastPingNonce: uint64(0),
wantLastPingMicros: int64(0),
wantTimeOffset: int64(0),
wantBytesSent: 158, // 134 version + 24 verack
wantBytesReceived: 158,
}
tests := []struct {
name string
setup func() (*peer.Peer, *peer.Peer, error)
}{
{
"basic handshake",
func() (*peer.Peer, *peer.Peer, error) {
inConn, outConn := pipe(
&conn{raddr: "10.0.0.1:8333"},
&conn{raddr: "10.0.0.2:8333"},
)
inPeer := peer.NewInboundPeer(peerCfg)
inPeer.Connect(inConn)
outPeer, err := peer.NewOutboundPeer(peerCfg, "10.0.0.2:8333")
if err != nil {
return nil, nil, err
}
outPeer.Connect(outConn)
for i := 0; i < 4; i++ {
select {
case <-verack:
case <-time.After(time.Second):
return nil, nil, errors.New("verack timeout")
}
}
return inPeer, outPeer, nil
},
},
{
"socks proxy",
func() (*peer.Peer, *peer.Peer, error) {
inConn, outConn := pipe(
&conn{raddr: "10.0.0.1:8333", proxy: true},
&conn{raddr: "10.0.0.2:8333"},
)
inPeer := peer.NewInboundPeer(peerCfg)
inPeer.Connect(inConn)
outPeer, err := peer.NewOutboundPeer(peerCfg, "10.0.0.2:8333")
if err != nil {
return nil, nil, err
}
outPeer.Connect(outConn)
for i := 0; i < 4; i++ {
select {
case <-verack:
case <-time.After(time.Second):
return nil, nil, errors.New("verack timeout")
}
}
return inPeer, outPeer, nil
},
},
}
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
inPeer, outPeer, err := test.setup()
if err != nil {
t.Errorf("TestPeerConnection setup #%d: unexpected err %v", i, err)
return
}
testPeer(t, inPeer, wantStats)
testPeer(t, outPeer, wantStats)
inPeer.Disconnect()
outPeer.Disconnect()
inPeer.WaitForDisconnect()
outPeer.WaitForDisconnect()
}
}