Erlang与ActionScript3采用JSON格式进行Socket通讯

前提：
需要下载[url=http://code.google.com/p/as3corelib/]as3corelib[/url]来为ActionScript3处理JSON codec

server.erl
[code]
-module(server).
-export([start/0,start/1,process/1]).
-define(defPort, 8888).

start() -> start(?defPort).

start(Port) ->
case gen_tcp:listen(Port, [binary, {packet, 0}, {active, false}]) of
{ok, LSock} -> server_loop(LSock);
{error, Reason} -> exit({Port,Reason})
end.

%% main server loop - wait for next connection, spawn child to process it
server_loop(LSock) ->
case gen_tcp:accept(LSock) of
{ok, Sock} ->
spawn(?MODULE,process,[Sock]),
server_loop(LSock);
{error, Reason} ->
exit({accept,Reason})
end.

%% process current connection
process(Sock) ->
Req = do_recv(Sock),
io:format("~p~n", [Req]),
{ok, D, []} = rfc4627:decode(Req),
{obj, [{"name", _Name}, {"age", Age}]} = D,
Name = binary_to_list(_Name),
io:format("Name: ~p, Age: ~p~n", [Name, Age]),
Resp = rfc4627:encode({obj, [{"name", 'Hideto2'}, {"age", 24}]}),
do_send(Sock,Resp),
gen_tcp:close(Sock).

%% send a line of text to the socket
do_send(Sock,Msg) ->
case gen_tcp:send(Sock, Msg) of
ok -> ok;
{error, Reason} -> exit(Reason)
end.

%% receive data from the socket
do_recv(Sock) ->
case gen_tcp:recv(Sock, 0) of
{ok, Bin} -> binary_to_list(Bin);
{error, closed} -> exit(closed);
{error, Reason} -> exit(Reason)
end.
[/code]

Person.as
[code]
package
{
public class Person
{
public var name:String;
public var age:int;
public function Person()
{
}
}
}
[/code]

Client.as
[code]
package {
import com.adobe.serialization.json.JSON;

import flash.display.Sprite;
import flash.events.*;
import flash.net.Socket;
import flash.text.*;

public class Client extends Sprite
{
private var socket:Socket;
private var myField:TextField;
private var send_data:Person;
public function Client()
{
socket = new Socket();
myField = new TextField();
send_data = new Person();
send_data.name = "Hideto";
send_data.age = 23;
socket.addEventListener(ProgressEvent.SOCKET_DATA, onSocketData);
socket.connect("localhost", 8888);
socket.writeUTFBytes(JSON.encode(send_data));
socket.flush();
myField.x = 20;
myField.y = 30;
myField.text = "test";
myField.autoSize = TextFieldAutoSize.LEFT;
addChild(myField);
}
private function onSocketData(event:ProgressEvent):void {
while(socket.bytesAvailable) {
var recv_data:* = JSON.decode(socket.readUTFBytes(socket.bytesAvailable));
myField.text = "Name: " + recv_data.name + ", age: " + recv_data.age.toString();
}
}
}
}
[/code]

运行Erlang服务器端：
[code]
Eshell> c(server).
Eshell> server:start().
"{\"name\":\"Hideto\",\"age\":23}"
Name: "Hideto", Age: 23
[/code]
这里打印出了Erlang Socket Server接收到的AS3 Client发过来的JSON decode过的一个person对象

运行AS3客户端：
client.html上首先显示“test”，然后异步处理完Socket消息发送和接受后，decode Erlang Server端发过来的person对象，将页面上的TextField替换为“Name: Hideto2, age: 24”