plugeth/p2p/peer_test.go
Felix Lange f1d710af00 p2p: fix Peer shutdown deadlocks
There were multiple synchronization issues in the disconnect handling,
all caused by the odd special-casing of Peer.readLoop errors. Remove the
special handling of read errors and make readLoop part of the Peer
WaitGroup.

Thanks to @Gustav-Simonsson for pointing at arrows in a diagram
and playing rubber-duck.
2015-04-10 13:26:27 +02:00

252 lines
6.0 KiB
Go

package p2p
import (
"bytes"
"errors"
"fmt"
"math/rand"
"net"
"reflect"
"testing"
"time"
)
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) (func(), *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() }()
closer := func() {
p1.Close()
fd1.Close()
}
return closer, &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()
Send(rw, baseProtocolLength+2, []uint{1})
Send(rw, baseProtocolLength+3, []uint{2})
Send(rw, baseProtocolLength+4, []uint{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 := SendItems(rw, 2); err == nil {
t.Error("expected error for out-of-range msg code, got nil")
}
if err := SendItems(rw, 1, "foo", "bar"); err != nil {
t.Errorf("write error: %v", err)
}
return nil
},
}
closer, rw, _, _ := testPeer([]Protocol{proto})
defer closer()
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()
emptymsg := func(code uint64) Msg {
return Msg{Code: code, Size: 0, Payload: bytes.NewReader(nil)}
}
// test write errors
if err := peer.writeProtoMsg("b", emptymsg(3)); err == nil {
t.Errorf("expected error for unknown protocol, got nil")
}
if err := peer.writeProtoMsg("discard", emptymsg(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", emptymsg(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()
if err := SendItems(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()
if err := SendItems(rw, discMsg, DiscQuitting); err != nil {
t.Fatal(err)
}
if err := ExpectMsg(rw, discMsg, []interface{}{DiscRequested}); err != nil {
t.Error(err)
}
closer()
if reason := <-disc; reason != DiscRequested {
t.Errorf("run returned wrong reason: got %v, want %v", reason, DiscRequested)
}
}
// This test is supposed to verify that Peer can reliably handle
// multiple causes of disconnection occurring at the same time.
func TestPeerDisconnectRace(t *testing.T) {
defer testlog(t).detach()
maybe := func() bool { return rand.Intn(1) == 1 }
for i := 0; i < 1000; i++ {
protoclose := make(chan error)
protodisc := make(chan DiscReason)
closer, rw, p, disc := testPeer([]Protocol{
{
Name: "closereq",
Run: func(p *Peer, rw MsgReadWriter) error { return <-protoclose },
Length: 1,
},
{
Name: "disconnect",
Run: func(p *Peer, rw MsgReadWriter) error { p.Disconnect(<-protodisc); return nil },
Length: 1,
},
})
// Simulate incoming messages.
go SendItems(rw, baseProtocolLength+1)
go SendItems(rw, baseProtocolLength+2)
// Close the network connection.
go closer()
// Make protocol "closereq" return.
protoclose <- errors.New("protocol closed")
// Make protocol "disconnect" call peer.Disconnect
protodisc <- DiscAlreadyConnected
// In some cases, simulate something else calling peer.Disconnect.
if maybe() {
go p.Disconnect(DiscInvalidIdentity)
}
// In some cases, simulate remote requesting a disconnect.
if maybe() {
go SendItems(rw, discMsg, DiscQuitting)
}
select {
case <-disc:
case <-time.After(2 * time.Second):
// Peer.run should return quickly. If it doesn't the Peer
// goroutines are probably deadlocked. Call panic in order to
// show the stacks.
panic("Peer.run took to long to return.")
}
}
}
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
}