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// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package rpc
import (
"fmt"
"http/httptest"
"io"
"log"
"net"
"os"
"runtime"
"strings"
"sync"
"sync/atomic"
"testing"
"time"
)
var (
newServer *Server
serverAddr, newServerAddr string
httpServerAddr string
once, newOnce, httpOnce sync.Once
)
const (
second = 1e9
newHttpPath = "/foo"
)
type Args struct {
A, B int
}
type Reply struct {
C int
}
type Arith int
// Some of Arith's methods have value args, some have pointer args. That's deliberate.
func (t *Arith) Add(args Args, reply *Reply) os.Error {
reply.C = args.A + args.B
return nil
}
func (t *Arith) Mul(args *Args, reply *Reply) os.Error {
reply.C = args.A * args.B
return nil
}
func (t *Arith) Div(args Args, reply *Reply) os.Error {
if args.B == 0 {
return os.NewError("divide by zero")
}
reply.C = args.A / args.B
return nil
}
func (t *Arith) String(args *Args, reply *string) os.Error {
*reply = fmt.Sprintf("%d+%d=%d", args.A, args.B, args.A+args.B)
return nil
}
func (t *Arith) Scan(args string, reply *Reply) (err os.Error) {
_, err = fmt.Sscan(args, &reply.C)
return
}
func (t *Arith) Error(args *Args, reply *Reply) os.Error {
panic("ERROR")
}
func listenTCP() (net.Listener, string) {
l, e := net.Listen("tcp", "127.0.0.1:0") // any available address
if e != nil {
log.Fatalf("net.Listen tcp :0: %v", e)
}
return l, l.Addr().String()
}
func startServer() {
Register(new(Arith))
var l net.Listener
l, serverAddr = listenTCP()
log.Println("Test RPC server listening on", serverAddr)
go Accept(l)
HandleHTTP()
httpOnce.Do(startHttpServer)
}
func startNewServer() {
newServer = NewServer()
newServer.Register(new(Arith))
var l net.Listener
l, newServerAddr = listenTCP()
log.Println("NewServer test RPC server listening on", newServerAddr)
go Accept(l)
newServer.HandleHTTP(newHttpPath, "/bar")
httpOnce.Do(startHttpServer)
}
func startHttpServer() {
server := httptest.NewServer(nil)
httpServerAddr = server.Listener.Addr().String()
log.Println("Test HTTP RPC server listening on", httpServerAddr)
}
func TestRPC(t *testing.T) {
once.Do(startServer)
testRPC(t, serverAddr)
newOnce.Do(startNewServer)
testRPC(t, newServerAddr)
}
func testRPC(t *testing.T, addr string) {
client, err := Dial("tcp", addr)
if err != nil {
t.Fatal("dialing", err)
}
// Synchronous calls
args := &Args{7, 8}
reply := new(Reply)
err = client.Call("Arith.Add", args, reply)
if err != nil {
t.Errorf("Add: expected no error but got string %q", err.String())
}
if reply.C != args.A+args.B {
t.Errorf("Add: expected %d got %d", reply.C, args.A+args.B)
}
// Nonexistent method
args = &Args{7, 0}
reply = new(Reply)
err = client.Call("Arith.BadOperation", args, reply)
// expect an error
if err == nil {
t.Error("BadOperation: expected error")
} else if !strings.HasPrefix(err.String(), "rpc: can't find method ") {
t.Errorf("BadOperation: expected can't find method error; got %q", err)
}
// Unknown service
args = &Args{7, 8}
reply = new(Reply)
err = client.Call("Arith.Unknown", args, reply)
if err == nil {
t.Error("expected error calling unknown service")
} else if strings.Index(err.String(), "method") < 0 {
t.Error("expected error about method; got", err)
}
// Out of order.
args = &Args{7, 8}
mulReply := new(Reply)
mulCall := client.Go("Arith.Mul", args, mulReply, nil)
addReply := new(Reply)
addCall := client.Go("Arith.Add", args, addReply, nil)
addCall = <-addCall.Done
if addCall.Error != nil {
t.Errorf("Add: expected no error but got string %q", addCall.Error.String())
}
if addReply.C != args.A+args.B {
t.Errorf("Add: expected %d got %d", addReply.C, args.A+args.B)
}
mulCall = <-mulCall.Done
if mulCall.Error != nil {
t.Errorf("Mul: expected no error but got string %q", mulCall.Error.String())
}
if mulReply.C != args.A*args.B {
t.Errorf("Mul: expected %d got %d", mulReply.C, args.A*args.B)
}
// Error test
args = &Args{7, 0}
reply = new(Reply)
err = client.Call("Arith.Div", args, reply)
// expect an error: zero divide
if err == nil {
t.Error("Div: expected error")
} else if err.String() != "divide by zero" {
t.Error("Div: expected divide by zero error; got", err)
}
// Bad type.
reply = new(Reply)
err = client.Call("Arith.Add", reply, reply) // args, reply would be the correct thing to use
if err == nil {
t.Error("expected error calling Arith.Add with wrong arg type")
} else if strings.Index(err.String(), "type") < 0 {
t.Error("expected error about type; got", err)
}
// Non-struct argument
const Val = 12345
str := fmt.Sprint(Val)
reply = new(Reply)
err = client.Call("Arith.Scan", &str, reply)
if err != nil {
t.Errorf("Scan: expected no error but got string %q", err.String())
} else if reply.C != Val {
t.Errorf("Scan: expected %d got %d", Val, reply.C)
}
// Non-struct reply
args = &Args{27, 35}
str = ""
err = client.Call("Arith.String", args, &str)
if err != nil {
t.Errorf("String: expected no error but got string %q", err.String())
}
expect := fmt.Sprintf("%d+%d=%d", args.A, args.B, args.A+args.B)
if str != expect {
t.Errorf("String: expected %s got %s", expect, str)
}
args = &Args{7, 8}
reply = new(Reply)
err = client.Call("Arith.Mul", args, reply)
if err != nil {
t.Errorf("Mul: expected no error but got string %q", err.String())
}
if reply.C != args.A*args.B {
t.Errorf("Mul: expected %d got %d", reply.C, args.A*args.B)
}
}
func TestHTTP(t *testing.T) {
once.Do(startServer)
testHTTPRPC(t, "")
newOnce.Do(startNewServer)
testHTTPRPC(t, newHttpPath)
}
func testHTTPRPC(t *testing.T, path string) {
var client *Client
var err os.Error
if path == "" {
client, err = DialHTTP("tcp", httpServerAddr)
} else {
client, err = DialHTTPPath("tcp", httpServerAddr, path)
}
if err != nil {
t.Fatal("dialing", err)
}
// Synchronous calls
args := &Args{7, 8}
reply := new(Reply)
err = client.Call("Arith.Add", args, reply)
if err != nil {
t.Errorf("Add: expected no error but got string %q", err.String())
}
if reply.C != args.A+args.B {
t.Errorf("Add: expected %d got %d", reply.C, args.A+args.B)
}
}
// CodecEmulator provides a client-like api and a ServerCodec interface.
// Can be used to test ServeRequest.
type CodecEmulator struct {
server *Server
serviceMethod string
args *Args
reply *Reply
err os.Error
}
func (codec *CodecEmulator) Call(serviceMethod string, args *Args, reply *Reply) os.Error {
codec.serviceMethod = serviceMethod
codec.args = args
codec.reply = reply
codec.err = nil
var serverError os.Error
if codec.server == nil {
serverError = ServeRequest(codec)
} else {
serverError = codec.server.ServeRequest(codec)
}
if codec.err == nil && serverError != nil {
codec.err = serverError
}
return codec.err
}
func (codec *CodecEmulator) ReadRequestHeader(req *Request) os.Error {
req.ServiceMethod = codec.serviceMethod
req.Seq = 0
return nil
}
func (codec *CodecEmulator) ReadRequestBody(argv interface{}) os.Error {
if codec.args == nil {
return io.ErrUnexpectedEOF
}
*(argv.(*Args)) = *codec.args
return nil
}
func (codec *CodecEmulator) WriteResponse(resp *Response, reply interface{}) os.Error {
if resp.Error != "" {
codec.err = os.NewError(resp.Error)
} else {
*codec.reply = *(reply.(*Reply))
}
return nil
}
func (codec *CodecEmulator) Close() os.Error {
return nil
}
func TestServeRequest(t *testing.T) {
once.Do(startServer)
testServeRequest(t, nil)
newOnce.Do(startNewServer)
testServeRequest(t, newServer)
}
func testServeRequest(t *testing.T, server *Server) {
client := CodecEmulator{server: server}
args := &Args{7, 8}
reply := new(Reply)
err := client.Call("Arith.Add", args, reply)
if err != nil {
t.Errorf("Add: expected no error but got string %q", err.String())
}
if reply.C != args.A+args.B {
t.Errorf("Add: expected %d got %d", reply.C, args.A+args.B)
}
err = client.Call("Arith.Add", nil, reply)
if err == nil {
t.Errorf("expected error calling Arith.Add with nil arg")
}
}
type ReplyNotPointer int
type ArgNotPublic int
type ReplyNotPublic int
type local struct{}
func (t *ReplyNotPointer) ReplyNotPointer(args *Args, reply Reply) os.Error {
return nil
}
func (t *ArgNotPublic) ArgNotPublic(args *local, reply *Reply) os.Error {
return nil
}
func (t *ReplyNotPublic) ReplyNotPublic(args *Args, reply *local) os.Error {
return nil
}
// Check that registration handles lots of bad methods and a type with no suitable methods.
func TestRegistrationError(t *testing.T) {
err := Register(new(ReplyNotPointer))
if err == nil {
t.Errorf("expected error registering ReplyNotPointer")
}
err = Register(new(ArgNotPublic))
if err == nil {
t.Errorf("expected error registering ArgNotPublic")
}
err = Register(new(ReplyNotPublic))
if err == nil {
t.Errorf("expected error registering ReplyNotPublic")
}
}
type WriteFailCodec int
func (WriteFailCodec) WriteRequest(*Request, interface{}) os.Error {
// the panic caused by this error used to not unlock a lock.
return os.NewError("fail")
}
func (WriteFailCodec) ReadResponseHeader(*Response) os.Error {
time.Sleep(120e9)
panic("unreachable")
}
func (WriteFailCodec) ReadResponseBody(interface{}) os.Error {
time.Sleep(120e9)
panic("unreachable")
}
func (WriteFailCodec) Close() os.Error {
return nil
}
func TestSendDeadlock(t *testing.T) {
client := NewClientWithCodec(WriteFailCodec(0))
done := make(chan bool)
go func() {
testSendDeadlock(client)
testSendDeadlock(client)
done <- true
}()
select {
case <-done:
return
case <-time.After(5e9):
t.Fatal("deadlock")
}
}
func testSendDeadlock(client *Client) {
defer func() {
recover()
}()
args := &Args{7, 8}
reply := new(Reply)
client.Call("Arith.Add", args, reply)
}
func dialDirect() (*Client, os.Error) {
return Dial("tcp", serverAddr)
}
func dialHTTP() (*Client, os.Error) {
return DialHTTP("tcp", httpServerAddr)
}
func countMallocs(dial func() (*Client, os.Error), t *testing.T) uint64 {
once.Do(startServer)
client, err := dial()
if err != nil {
t.Fatal("error dialing", err)
}
args := &Args{7, 8}
reply := new(Reply)
runtime.UpdateMemStats()
mallocs := 0 - runtime.MemStats.Mallocs
const count = 100
for i := 0; i < count; i++ {
err := client.Call("Arith.Add", args, reply)
if err != nil {
t.Errorf("Add: expected no error but got string %q", err.String())
}
if reply.C != args.A+args.B {
t.Errorf("Add: expected %d got %d", reply.C, args.A+args.B)
}
}
runtime.UpdateMemStats()
mallocs += runtime.MemStats.Mallocs
return mallocs / count
}
func TestCountMallocs(t *testing.T) {
fmt.Printf("mallocs per rpc round trip: %d\n", countMallocs(dialDirect, t))
}
func TestCountMallocsOverHTTP(t *testing.T) {
fmt.Printf("mallocs per HTTP rpc round trip: %d\n", countMallocs(dialHTTP, t))
}
type writeCrasher struct{}
func (writeCrasher) Close() os.Error {
return nil
}
func (writeCrasher) Read(p []byte) (int, os.Error) {
return 0, os.EOF
}
func (writeCrasher) Write(p []byte) (int, os.Error) {
return 0, os.NewError("fake write failure")
}
func TestClientWriteError(t *testing.T) {
c := NewClient(writeCrasher{})
res := false
err := c.Call("foo", 1, &res)
if err == nil {
t.Fatal("expected error")
}
if err.String() != "fake write failure" {
t.Error("unexpected value of error:", err)
}
}
func benchmarkEndToEnd(dial func() (*Client, os.Error), b *testing.B) {
b.StopTimer()
once.Do(startServer)
client, err := dial()
if err != nil {
fmt.Println("error dialing", err)
return
}
// Synchronous calls
args := &Args{7, 8}
procs := runtime.GOMAXPROCS(-1)
N := int32(b.N)
var wg sync.WaitGroup
wg.Add(procs)
b.StartTimer()
for p := 0; p < procs; p++ {
go func() {
reply := new(Reply)
for atomic.AddInt32(&N, -1) >= 0 {
err = client.Call("Arith.Add", args, reply)
if err != nil {
fmt.Printf("Add: expected no error but got string %q", err.String())
panic("rpc error")
}
if reply.C != args.A+args.B {
fmt.Printf("Add: expected %d got %d", reply.C, args.A+args.B)
panic("rpc error")
}
}
wg.Done()
}()
}
wg.Wait()
}
func benchmarkEndToEndAsync(dial func() (*Client, os.Error), b *testing.B) {
const MaxConcurrentCalls = 100
b.StopTimer()
once.Do(startServer)
client, err := dial()
if err != nil {
fmt.Println("error dialing", err)
return
}
// Asynchronous calls
args := &Args{7, 8}
procs := 4 * runtime.GOMAXPROCS(-1)
send := int32(b.N)
recv := int32(b.N)
var wg sync.WaitGroup
wg.Add(procs)
gate := make(chan bool, MaxConcurrentCalls)
res := make(chan *Call, MaxConcurrentCalls)
b.StartTimer()
for p := 0; p < procs; p++ {
go func() {
for atomic.AddInt32(&send, -1) >= 0 {
gate <- true
reply := new(Reply)
client.Go("Arith.Add", args, reply, res)
}
}()
go func() {
for call := range res {
a := call.Args.(*Args).A
b := call.Args.(*Args).B
c := call.Reply.(*Reply).C
if a+b != c {
fmt.Printf("Add: expected %d got %d", a+b, c)
panic("incorrect reply")
}
<-gate
if atomic.AddInt32(&recv, -1) == 0 {
close(res)
}
}
wg.Done()
}()
}
wg.Wait()
}
func BenchmarkEndToEnd(b *testing.B) {
benchmarkEndToEnd(dialDirect, b)
}
func BenchmarkEndToEndHTTP(b *testing.B) {
benchmarkEndToEnd(dialHTTP, b)
}
func BenchmarkEndToEndAsync(b *testing.B) {
benchmarkEndToEndAsync(dialDirect, b)
}
func BenchmarkEndToEndAsyncHTTP(b *testing.B) {
benchmarkEndToEndAsync(dialHTTP, b)
}
|