path: root/p2p/peer_test.go

package p2p

import (
    "bytes"
    "fmt"
    "io"
    "io/ioutil"
    "net"
    "reflect"
    "testing"
    "time"

    "github.com/ethereum/go-ethereum/rlp"
)

var discard = Protocol{
    Name:   "discard",
    Length: 1,
    Run: func(p *Peer, rw MsgReadWriter) error {
        for {
            msg, err := rw.ReadMsg()
            if err != nil {
                return err
            }
            fmt.Printf("discarding %d\n", msg.Code)
            if err = msg.Discard(); err != nil {
                return err
            }
        }
    },
}

func testPeer(protos []Protocol) (io.Closer, *conn, *Peer, <-chan DiscReason) {
    fd1, _ := net.Pipe()
    hs1 := &protoHandshake{ID: randomID(), Version: baseProtocolVersion}
    hs2 := &protoHandshake{ID: randomID(), Version: baseProtocolVersion}
    for _, p := range protos {
        hs1.Caps = append(hs1.Caps, p.cap())
        hs2.Caps = append(hs2.Caps, p.cap())
    }

    p1, p2 := MsgPipe()
    peer := newPeer(fd1, &conn{p1, hs1}, protos)
    errc := make(chan DiscReason, 1)
    go func() { errc <- peer.run() }()

    return p1, &conn{p2, hs2}, peer, errc
}

func TestPeerProtoReadMsg(t *testing.T) {
    defer testlog(t).detach()

    done := make(chan struct{})
    proto := Protocol{
        Name:   "a",
        Length: 5,
        Run: func(peer *Peer, rw MsgReadWriter) error {
            if err := expectMsg(rw, 2, []uint{1}); err != nil {
                t.Error(err)
            }
            if err := expectMsg(rw, 3, []uint{2}); err != nil {
                t.Error(err)
            }
            if err := expectMsg(rw, 4, []uint{3}); err != nil {
                t.Error(err)
            }
            close(done)
            return nil
        },
    }

    closer, rw, _, errc := testPeer([]Protocol{proto})
    defer closer.Close()

    EncodeMsg(rw, baseProtocolLength+2, 1)
    EncodeMsg(rw, baseProtocolLength+3, 2)
    EncodeMsg(rw, baseProtocolLength+4, 3)

    select {
    case <-done:
    case err := <-errc:
        t.Errorf("peer returned: %v", err)
    case <-time.After(2 * time.Second):
        t.Errorf("receive timeout")
    }
}

func TestPeerProtoEncodeMsg(t *testing.T) {
    defer testlog(t).detach()

    proto := Protocol{
        Name:   "a",
        Length: 2,
        Run: func(peer *Peer, rw MsgReadWriter) error {
            if err := EncodeMsg(rw, 2); err == nil {
                t.Error("expected error for out-of-range msg code, got nil")
            }
            if err := EncodeMsg(rw, 1, "foo", "bar"); err != nil {
                t.Errorf("write error: %v", err)
            }
            return nil
        },
    }
    closer, rw, _, _ := testPeer([]Protocol{proto})
    defer closer.Close()

    if err := expectMsg(rw, 17, []string{"foo", "bar"}); err != nil {
        t.Error(err)
    }
}

func TestPeerWriteForBroadcast(t *testing.T) {
    defer testlog(t).detach()

    closer, rw, peer, peerErr := testPeer([]Protocol{discard})
    defer closer.Close()

    // test write errors
    if err := peer.writeProtoMsg("b", NewMsg(3)); err == nil {
        t.Errorf("expected error for unknown protocol, got nil")
    }
    if err := peer.writeProtoMsg("discard", NewMsg(8)); err == nil {
        t.Errorf("expected error for out-of-range msg code, got nil")
    } else if perr, ok := err.(*peerError); !ok || perr.Code != errInvalidMsgCode {
        t.Errorf("wrong error for out-of-range msg code, got %#v", err)
    }

    // setup for reading the message on the other end
    read := make(chan struct{})
    go func() {
        if err := expectMsg(rw, 16, nil); err != nil {
            t.Error(err)
        }
        close(read)
    }()

    // test successful write
    if err := peer.writeProtoMsg("discard", NewMsg(0)); err != nil {
        t.Errorf("expect no error for known protocol: %v", err)
    }
    select {
    case <-read:
    case err := <-peerErr:
        t.Fatalf("peer stopped: %v", err)
    }
}

func TestPeerPing(t *testing.T) {
    defer testlog(t).detach()

    closer, rw, _, _ := testPeer(nil)
    defer closer.Close()
    if err := EncodeMsg(rw, pingMsg); err != nil {
        t.Fatal(err)
    }
    if err := expectMsg(rw, pongMsg, nil); err != nil {
        t.Error(err)
    }
}

func TestPeerDisconnect(t *testing.T) {
    defer testlog(t).detach()

    closer, rw, _, disc := testPeer(nil)
    defer closer.Close()
    if err := EncodeMsg(rw, discMsg, DiscQuitting); err != nil {
        t.Fatal(err)
    }
    if err := expectMsg(rw, discMsg, []interface{}{DiscRequested}); err != nil {
        t.Error(err)
    }
    closer.Close() // make test end faster
    if reason := <-disc; reason != DiscRequested {
        t.Errorf("run returned wrong reason: got %v, want %v", reason, DiscRequested)
    }
}

func TestNewPeer(t *testing.T) {
    name := "nodename"
    caps := []Cap{{"foo", 2}, {"bar", 3}}
    id := randomID()
    p := NewPeer(id, name, caps)
    if p.ID() != id {
        t.Errorf("ID mismatch: got %v, expected %v", p.ID(), id)
    }
    if p.Name() != name {
        t.Errorf("Name mismatch: got %v, expected %v", p.Name(), name)
    }
    if !reflect.DeepEqual(p.Caps(), caps) {
        t.Errorf("Caps mismatch: got %v, expected %v", p.Caps(), caps)
    }

    p.Disconnect(DiscAlreadyConnected) // Should not hang
}

// expectMsg reads a message from r and verifies that its
// code and encoded RLP content match the provided values.
// If content is nil, the payload is discarded and not verified.
func expectMsg(r MsgReader, code uint64, content interface{}) error {
    msg, err := r.ReadMsg()
    if err != nil {
        return err
    }
    if msg.Code != code {
        return fmt.Errorf("message code mismatch: got %d, expected %d", msg.Code, code)
    }
    if content == nil {
        return msg.Discard()
    } else {
        contentEnc, err := rlp.EncodeToBytes(content)
        if err != nil {
            panic("content encode error: " + err.Error())
        }
        if int(msg.Size) != len(contentEnc) {
            return fmt.Errorf("message size mismatch: got %d, want %d", msg.Size, len(contentEnc))
        }
        actualContent, err := ioutil.ReadAll(msg.Payload)
        if err != nil {
            return err
        }
        if !bytes.Equal(actualContent, contentEnc) {
            return fmt.Errorf("message payload mismatch:\ngot:  %x\nwant: %x", actualContent, contentEnc)
        }
    }
    return nil
}