go-ethereum/rpc/client_test.go
Lewis Marshall 9feec51e2d p2p: add network simulation framework (#14982)
This commit introduces a network simulation framework which
can be used to run simulated networks of devp2p nodes. The
intention is to use this for testing protocols, performing
benchmarks and visualising emergent network behaviour.
2017-09-25 10:08:07 +02:00

568 lines
15 KiB
Go

// Copyright 2016 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 rpc
import (
"context"
"fmt"
"math/rand"
"net"
"net/http"
"net/http/httptest"
"os"
"reflect"
"runtime"
"sync"
"testing"
"time"
"github.com/davecgh/go-spew/spew"
"github.com/ethereum/go-ethereum/log"
)
func TestClientRequest(t *testing.T) {
server := newTestServer("service", new(Service))
defer server.Stop()
client := DialInProc(server)
defer client.Close()
var resp Result
if err := client.Call(&resp, "service_echo", "hello", 10, &Args{"world"}); err != nil {
t.Fatal(err)
}
if !reflect.DeepEqual(resp, Result{"hello", 10, &Args{"world"}}) {
t.Errorf("incorrect result %#v", resp)
}
}
func TestClientBatchRequest(t *testing.T) {
server := newTestServer("service", new(Service))
defer server.Stop()
client := DialInProc(server)
defer client.Close()
batch := []BatchElem{
{
Method: "service_echo",
Args: []interface{}{"hello", 10, &Args{"world"}},
Result: new(Result),
},
{
Method: "service_echo",
Args: []interface{}{"hello2", 11, &Args{"world"}},
Result: new(Result),
},
{
Method: "no_such_method",
Args: []interface{}{1, 2, 3},
Result: new(int),
},
}
if err := client.BatchCall(batch); err != nil {
t.Fatal(err)
}
wantResult := []BatchElem{
{
Method: "service_echo",
Args: []interface{}{"hello", 10, &Args{"world"}},
Result: &Result{"hello", 10, &Args{"world"}},
},
{
Method: "service_echo",
Args: []interface{}{"hello2", 11, &Args{"world"}},
Result: &Result{"hello2", 11, &Args{"world"}},
},
{
Method: "no_such_method",
Args: []interface{}{1, 2, 3},
Result: new(int),
Error: &jsonError{Code: -32601, Message: "The method no_such_method_ does not exist/is not available"},
},
}
if !reflect.DeepEqual(batch, wantResult) {
t.Errorf("batch results mismatch:\ngot %swant %s", spew.Sdump(batch), spew.Sdump(wantResult))
}
}
// func TestClientCancelInproc(t *testing.T) { testClientCancel("inproc", t) }
func TestClientCancelWebsocket(t *testing.T) { testClientCancel("ws", t) }
func TestClientCancelHTTP(t *testing.T) { testClientCancel("http", t) }
func TestClientCancelIPC(t *testing.T) { testClientCancel("ipc", t) }
// This test checks that requests made through CallContext can be canceled by canceling
// the context.
func testClientCancel(transport string, t *testing.T) {
server := newTestServer("service", new(Service))
defer server.Stop()
// What we want to achieve is that the context gets canceled
// at various stages of request processing. The interesting cases
// are:
// - cancel during dial
// - cancel while performing a HTTP request
// - cancel while waiting for a response
//
// To trigger those, the times are chosen such that connections
// are killed within the deadline for every other call (maxKillTimeout
// is 2x maxCancelTimeout).
//
// Once a connection is dead, there is a fair chance it won't connect
// successfully because the accept is delayed by 1s.
maxContextCancelTimeout := 300 * time.Millisecond
fl := &flakeyListener{
maxAcceptDelay: 1 * time.Second,
maxKillTimeout: 600 * time.Millisecond,
}
var client *Client
switch transport {
case "ws", "http":
c, hs := httpTestClient(server, transport, fl)
defer hs.Close()
client = c
case "ipc":
c, l := ipcTestClient(server, fl)
defer l.Close()
client = c
default:
panic("unknown transport: " + transport)
}
// These tests take a lot of time, run them all at once.
// You probably want to run with -parallel 1 or comment out
// the call to t.Parallel if you enable the logging.
t.Parallel()
// The actual test starts here.
var (
wg sync.WaitGroup
nreqs = 10
ncallers = 6
)
caller := func(index int) {
defer wg.Done()
for i := 0; i < nreqs; i++ {
var (
ctx context.Context
cancel func()
timeout = time.Duration(rand.Int63n(int64(maxContextCancelTimeout)))
)
if index < ncallers/2 {
// For half of the callers, create a context without deadline
// and cancel it later.
ctx, cancel = context.WithCancel(context.Background())
time.AfterFunc(timeout, cancel)
} else {
// For the other half, create a context with a deadline instead. This is
// different because the context deadline is used to set the socket write
// deadline.
ctx, cancel = context.WithTimeout(context.Background(), timeout)
}
// Now perform a call with the context.
// The key thing here is that no call will ever complete successfully.
err := client.CallContext(ctx, nil, "service_sleep", 2*maxContextCancelTimeout)
if err != nil {
log.Debug(fmt.Sprint("got expected error:", err))
} else {
t.Errorf("no error for call with %v wait time", timeout)
}
cancel()
}
}
wg.Add(ncallers)
for i := 0; i < ncallers; i++ {
go caller(i)
}
wg.Wait()
}
func TestClientSubscribeInvalidArg(t *testing.T) {
server := newTestServer("service", new(Service))
defer server.Stop()
client := DialInProc(server)
defer client.Close()
check := func(shouldPanic bool, arg interface{}) {
defer func() {
err := recover()
if shouldPanic && err == nil {
t.Errorf("EthSubscribe should've panicked for %#v", arg)
}
if !shouldPanic && err != nil {
t.Errorf("EthSubscribe shouldn't have panicked for %#v", arg)
buf := make([]byte, 1024*1024)
buf = buf[:runtime.Stack(buf, false)]
t.Error(err)
t.Error(string(buf))
}
}()
client.EthSubscribe(context.Background(), arg, "foo_bar")
}
check(true, nil)
check(true, 1)
check(true, (chan int)(nil))
check(true, make(<-chan int))
check(false, make(chan int))
check(false, make(chan<- int))
}
func TestClientSubscribe(t *testing.T) {
server := newTestServer("eth", new(NotificationTestService))
defer server.Stop()
client := DialInProc(server)
defer client.Close()
nc := make(chan int)
count := 10
sub, err := client.EthSubscribe(context.Background(), nc, "someSubscription", count, 0)
if err != nil {
t.Fatal("can't subscribe:", err)
}
for i := 0; i < count; i++ {
if val := <-nc; val != i {
t.Fatalf("value mismatch: got %d, want %d", val, i)
}
}
sub.Unsubscribe()
select {
case v := <-nc:
t.Fatal("received value after unsubscribe:", v)
case err := <-sub.Err():
if err != nil {
t.Fatalf("Err returned a non-nil error after explicit unsubscribe: %q", err)
}
case <-time.After(1 * time.Second):
t.Fatalf("subscription not closed within 1s after unsubscribe")
}
}
func TestClientSubscribeCustomNamespace(t *testing.T) {
namespace := "custom"
server := newTestServer(namespace, new(NotificationTestService))
defer server.Stop()
client := DialInProc(server)
defer client.Close()
nc := make(chan int)
count := 10
sub, err := client.Subscribe(context.Background(), namespace, nc, "someSubscription", count, 0)
if err != nil {
t.Fatal("can't subscribe:", err)
}
for i := 0; i < count; i++ {
if val := <-nc; val != i {
t.Fatalf("value mismatch: got %d, want %d", val, i)
}
}
sub.Unsubscribe()
select {
case v := <-nc:
t.Fatal("received value after unsubscribe:", v)
case err := <-sub.Err():
if err != nil {
t.Fatalf("Err returned a non-nil error after explicit unsubscribe: %q", err)
}
case <-time.After(1 * time.Second):
t.Fatalf("subscription not closed within 1s after unsubscribe")
}
}
// In this test, the connection drops while EthSubscribe is
// waiting for a response.
func TestClientSubscribeClose(t *testing.T) {
service := &NotificationTestService{
gotHangSubscriptionReq: make(chan struct{}),
unblockHangSubscription: make(chan struct{}),
}
server := newTestServer("eth", service)
defer server.Stop()
client := DialInProc(server)
defer client.Close()
var (
nc = make(chan int)
errc = make(chan error)
sub *ClientSubscription
err error
)
go func() {
sub, err = client.EthSubscribe(context.Background(), nc, "hangSubscription", 999)
errc <- err
}()
<-service.gotHangSubscriptionReq
client.Close()
service.unblockHangSubscription <- struct{}{}
select {
case err := <-errc:
if err == nil {
t.Errorf("EthSubscribe returned nil error after Close")
}
if sub != nil {
t.Error("EthSubscribe returned non-nil subscription after Close")
}
case <-time.After(1 * time.Second):
t.Fatalf("EthSubscribe did not return within 1s after Close")
}
}
// This test checks that Client doesn't lock up when a single subscriber
// doesn't read subscription events.
func TestClientNotificationStorm(t *testing.T) {
server := newTestServer("eth", new(NotificationTestService))
defer server.Stop()
doTest := func(count int, wantError bool) {
client := DialInProc(server)
defer client.Close()
ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
defer cancel()
// Subscribe on the server. It will start sending many notifications
// very quickly.
nc := make(chan int)
sub, err := client.EthSubscribe(ctx, nc, "someSubscription", count, 0)
if err != nil {
t.Fatal("can't subscribe:", err)
}
defer sub.Unsubscribe()
// Process each notification, try to run a call in between each of them.
for i := 0; i < count; i++ {
select {
case val := <-nc:
if val != i {
t.Fatalf("(%d/%d) unexpected value %d", i, count, val)
}
case err := <-sub.Err():
if wantError && err != ErrSubscriptionQueueOverflow {
t.Fatalf("(%d/%d) got error %q, want %q", i, count, err, ErrSubscriptionQueueOverflow)
} else if !wantError {
t.Fatalf("(%d/%d) got unexpected error %q", i, count, err)
}
return
}
var r int
err := client.CallContext(ctx, &r, "eth_echo", i)
if err != nil {
if !wantError {
t.Fatalf("(%d/%d) call error: %v", i, count, err)
}
return
}
}
}
doTest(8000, false)
doTest(10000, true)
}
func TestClientHTTP(t *testing.T) {
server := newTestServer("service", new(Service))
defer server.Stop()
client, hs := httpTestClient(server, "http", nil)
defer hs.Close()
defer client.Close()
// Launch concurrent requests.
var (
results = make([]Result, 100)
errc = make(chan error)
wantResult = Result{"a", 1, new(Args)}
)
defer client.Close()
for i := range results {
i := i
go func() {
errc <- client.Call(&results[i], "service_echo",
wantResult.String, wantResult.Int, wantResult.Args)
}()
}
// Wait for all of them to complete.
timeout := time.NewTimer(5 * time.Second)
defer timeout.Stop()
for i := range results {
select {
case err := <-errc:
if err != nil {
t.Fatal(err)
}
case <-timeout.C:
t.Fatalf("timeout (got %d/%d) results)", i+1, len(results))
}
}
// Check results.
for i := range results {
if !reflect.DeepEqual(results[i], wantResult) {
t.Errorf("result %d mismatch: got %#v, want %#v", i, results[i], wantResult)
}
}
}
func TestClientReconnect(t *testing.T) {
startServer := func(addr string) (*Server, net.Listener) {
srv := newTestServer("service", new(Service))
l, err := net.Listen("tcp", addr)
if err != nil {
t.Fatal(err)
}
go http.Serve(l, srv.WebsocketHandler([]string{"*"}))
return srv, l
}
ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
defer cancel()
// Start a server and corresponding client.
s1, l1 := startServer("127.0.0.1:0")
client, err := DialContext(ctx, "ws://"+l1.Addr().String())
if err != nil {
t.Fatal("can't dial", err)
}
// Perform a call. This should work because the server is up.
var resp Result
if err := client.CallContext(ctx, &resp, "service_echo", "", 1, nil); err != nil {
t.Fatal(err)
}
// Shut down the server and try calling again. It shouldn't work.
l1.Close()
s1.Stop()
if err := client.CallContext(ctx, &resp, "service_echo", "", 2, nil); err == nil {
t.Error("successful call while the server is down")
t.Logf("resp: %#v", resp)
}
// Allow for some cool down time so we can listen on the same address again.
time.Sleep(2 * time.Second)
// Start it up again and call again. The connection should be reestablished.
// We spawn multiple calls here to check whether this hangs somehow.
s2, l2 := startServer(l1.Addr().String())
defer l2.Close()
defer s2.Stop()
start := make(chan struct{})
errors := make(chan error, 20)
for i := 0; i < cap(errors); i++ {
go func() {
<-start
var resp Result
errors <- client.CallContext(ctx, &resp, "service_echo", "", 3, nil)
}()
}
close(start)
errcount := 0
for i := 0; i < cap(errors); i++ {
if err = <-errors; err != nil {
errcount++
}
}
t.Log("err:", err)
if errcount > 1 {
t.Errorf("expected one error after disconnect, got %d", errcount)
}
}
func newTestServer(serviceName string, service interface{}) *Server {
server := NewServer()
if err := server.RegisterName(serviceName, service); err != nil {
panic(err)
}
return server
}
func httpTestClient(srv *Server, transport string, fl *flakeyListener) (*Client, *httptest.Server) {
// Create the HTTP server.
var hs *httptest.Server
switch transport {
case "ws":
hs = httptest.NewUnstartedServer(srv.WebsocketHandler([]string{"*"}))
case "http":
hs = httptest.NewUnstartedServer(srv)
default:
panic("unknown HTTP transport: " + transport)
}
// Wrap the listener if required.
if fl != nil {
fl.Listener = hs.Listener
hs.Listener = fl
}
// Connect the client.
hs.Start()
client, err := Dial(transport + "://" + hs.Listener.Addr().String())
if err != nil {
panic(err)
}
return client, hs
}
func ipcTestClient(srv *Server, fl *flakeyListener) (*Client, net.Listener) {
// Listen on a random endpoint.
endpoint := fmt.Sprintf("go-ethereum-test-ipc-%d-%d", os.Getpid(), rand.Int63())
if runtime.GOOS == "windows" {
endpoint = `\\.\pipe\` + endpoint
} else {
endpoint = os.TempDir() + "/" + endpoint
}
l, err := ipcListen(endpoint)
if err != nil {
panic(err)
}
// Connect the listener to the server.
if fl != nil {
fl.Listener = l
l = fl
}
go srv.ServeListener(l)
// Connect the client.
client, err := Dial(endpoint)
if err != nil {
panic(err)
}
return client, l
}
// flakeyListener kills accepted connections after a random timeout.
type flakeyListener struct {
net.Listener
maxKillTimeout time.Duration
maxAcceptDelay time.Duration
}
func (l *flakeyListener) Accept() (net.Conn, error) {
delay := time.Duration(rand.Int63n(int64(l.maxAcceptDelay)))
time.Sleep(delay)
c, err := l.Listener.Accept()
if err == nil {
timeout := time.Duration(rand.Int63n(int64(l.maxKillTimeout)))
time.AfterFunc(timeout, func() {
log.Debug(fmt.Sprintf("killing conn %v after %v", c.LocalAddr(), timeout))
c.Close()
})
}
return c, err
}