build of rpc fails test

[Hans]

Hi,

I've been trying to play with the rpc package without any luck, and
then noticed that the rpc package is not really passing its tests when
it gets built.

I see the following when I build Go:

gopack grc _test/rpc.a _gotest_.6
make[2]: Leaving directory `/home/hans/GoRoot/src/pkg/rpc'
2009/11/15 00:56:28 Test RPC server listening on [::]:38326
2009/11/15 00:56:28 Test HTTP RPC server listening on [::]:37240
2009/11/15 00:56:28 rpc: client protocol error: gob: type mismatch: no
fields matched compiling decoder for Reply
2009/11/15 00:56:28 rpc: client protocol error: gob: type mismatch: no
fields matched compiling decoder for Reply
2009/11/15 00:56:28 rpc: tearing down Arith connection: gob: type
mismatch: no fields matched compiling decoder for Args
PASS
make[1]: Leaving directory `/home/hans/GoRoot/src/pkg/rpc'

[Russ Cox]

> I see the following when I build Go:
>
> gopack grc _test/rpc.a _gotest_.6
> make[2]: Leaving directory `/home/hans/GoRoot/src/pkg/rpc'
> 2009/11/15 00:56:28 Test RPC server listening on  [::]:38326
> 2009/11/15 00:56:28 Test HTTP RPC server listening on  [::]:37240
> 2009/11/15 00:56:28 rpc: client protocol error: gob: type mismatch: no
> fields matched compiling decoder for Reply
> 2009/11/15 00:56:28 rpc: client protocol error: gob: type mismatch: no
> fields matched compiling decoder for Reply
> 2009/11/15 00:56:28 rpc: tearing down Arith connection: gob: type
> mismatch: no fields matched compiling decoder for Args
> PASS
> make[1]: Leaving directory `/home/hans/GoRoot/src/pkg/rpc'

Those error messages are printed because the test
is exercising error cases in the implementation.
I believe the test is passing.

Can you give more detail about what's not working for
you in the rpc package?

Russ

[Hans]

Yes, I made a small program that is almost identical to the example
given in the rpc package documentation.

When I run the client I get this:
2009/11/15 01:26:02 rpc: client protocol error: gob: internal error:
field numbers out of bounds
2009/11/15 01:26:02 error: gob: internal error: field numbers out of
bounds



type Args struct
{
Cmd, Arg int;
}

type Result struct
{
StdOut int;
}

//client
func main()
{
client, err := rpc.DialHTTP("tcp", "127.0.0.1:2000");
if err != nil
{
log.Exit("dialing:", err);
}
// Synchronous call
args := &commands.Args{1,2};
reply := new(commands.Result);

fmt.Println("calling");
err = client.Call("Server.Execute", args, reply);
if err != nil
{
log.Exit("error: ", err);
}
fmt.Println(reply.StdOut);
}

//server

func main()
{
cmdsvr := new(commands.Server);
rpc.Register(cmdsvr);
rpc.HandleHTTP();
l, e := net.Listen("tcp", ":2000");
if e != nil
{
log.Exit("listen error: ", e);
}
http.Serve(l, nil);
}

[Rob 'Commander' Pike]

The error looks like a bug but there's not enough code here to reproduce it. Can you please send me the complete files or, better yet, include them in a new bug report at golang.org? Thanks.

-rob

[Hans]

I can send it later- I'm away from my computer right now. The only
thing I left out was the function that would get called in the server.
It never gets that far.


On Nov 15, 2009, at 9:01 AM, "Rob 'Commander' Pike" <r...@google.com>
wrote:

[Hans]

Ok, here are all my source files.

I want to get a simple rpc example running, so I mostly copied the
example in the rpc package documentation. When I run the server and
then the client on the same machine, I get the following error on the
terminal running the client:

2009/11/15 14:20:29 rpc: client protocol error: gob: internal error:

field numbers out of bounds

2009/11/15 14:20:29 error: gob: internal error: field numbers out of
bounds

I get the following message on the terminal running the server:
2009/11/15 14:20:29 rpc: EOF

//---------------------------------------------------------------
// commands.go
package commands

import "fmt"
import "os"

type Args struct
{
Cmd, Arg int;
}

type Result struct
{

Out int;
}

type Server int

func (t *Server) Execute(args *Args, res *Result) os.Error
{
fmt.Println("params = ", args.Cmd, " ", args.Arg );
res.Out = 2;
return nil
}

//---------------------------------------------------------------
// client.go
package main

import "log"
import "rpc"
import "fmt"
import "./commands"

func main()
{
client, err := rpc.DialHTTP("tcp", "127.0.0.1:2000");
if err != nil
{
log.Exit("dialing:", err);
}

// Synchronous call
args := &commands.Args{1,2};
reply := new(commands.Result);

fmt.Println("calling");
err = client.Call("Server.Execute", args, reply);
if err != nil
{
log.Exit("error: ", err);
}

fmt.Println(reply.Out);
}


//---------------------------------------------------------------
// server.go
package main

import "log"
import "http"
import "net"
import "rpc"
import "./commands"

func main()
{
cmdsvr := new(commands.Server);
rpc.Register(cmdsvr);
rpc.HandleHTTP();
l, e := net.Listen("tcp", ":2000");
if e != nil
{
log.Exit("listen error: ", e);
}
http.Serve(l, nil);
}

I build with these commands:
6g commands.go

6g server.go
6l -o server server.6

6g client.go
6l -o client client.6