[zz]Apache Thrift学习小记

参考：

http://incubator.apache.org/thrift/

http://wiki.apache.org/thrift/FrontPage

 

http://jnb.ociweb.com/jnb/jnbJun2009.html非常好的入门教程

http://developers.facebook.com/thrift/thrift-20070401.pdfthrift开发者写的论文

http://wiki.apache.org/thrift/ThriftUsageC%2B%2B  官方的c++文档

 

 

Thrift是个啥东东？

来自wiki.apache.org/thrift/FrontPage的定义

 

Thrift is a software framework for scalable cross-language services development. 

Thrift是为了实现跨语言服务访问的一个框架

 

Thrift allows you to define data types and service interfaces in a simple definition file.

Thrift定义了数据和服务的描述方式，是一种IDL

 

Taking that file as input, the compiler generates code to be used to easily build RPC clients and servers that communicate seamlessly across programming languages.

写一个定义文件，就可以使用thrift来生成某种语言RPC客户端和服务端程序框架。你只需要考虑如何实现你的服务就可以了。并且它支持很多种语言。

 

这有点像web service, 定义好一个web service服务描述文件后，可以使用如axis等工具生成服务器端或客户端的框架程序。

 

为什么还需要Thrift

thrift-20070401.pdf中有解释。

1、多语言开发的需要

比如其中提到的搜索服务，LAMP本身没有这个功能，开发者可能使用C++开发，php如何访问这个服务呢？于是需要有一种高效的跨语言访问的方法。

2、性能问题

web service也可以实现多语言互访问的功能，但xml文件太大，性能不行。Thrift可以使用二进值的格式。

 

开始测试

实现一个简单的服务，就是根据loginName得到User, user中有userId,loginName, name, password

 

第一步，写Thrift IDL文件 ，user.thrift，

 

namespace java mytest.thrift.gen
namespace py mytest.thrift
struct User {
  1: i32    userId,
  2: string loginName,
  3: string password,
  4: string name
}
exception UserNotFound {
  1: string message
}
service UserService {
  User getUser(1:string loginName) throws (1:UserNotFound unf),
  list<User> getUsers()
}

 

 

第二步，生成java和python代码

thrift --gen java user.thrift

thrift --gen py user.thrift

 

第三步，实现java服务端

参见：http://wiki.apache.org/thrift/ThriftUsageJava

 

服务实现 UserServiceHandler.java

 

 

package myserver;
import java.util.ArrayList;
import java.util.List;
import mytest.thrift.gen.User;
import mytest.thrift.gen.UserNotFound;
import mytest.thrift.gen.UserService;
import org.apache.thrift.TException;
public class UserServiceHandler implements UserService.Iface {
    @Override
    public User getUser(String loginName) throws UserNotFound, TException {
        if (!"login1".equals(loginName)) {
            UserNotFound e = new UserNotFound("User not Found!");
            throw e;
        }
        User user = new User();
        user.setUserId(100);
        user.setLoginName("login1");
        user.setPassword("pwd1");
        user.setName("user1");
        return user;
    }
    @Override
    public List<User> getUsers() throws TException {
        List<User> list = new ArrayList<User>();
        User user = new User();
        user.setUserId(100);
        user.setLoginName("login1");
        user.setPassword("pwd1");
        user.setName("user1");
        list.add(user);
        User user2 = new User();
        user2.setUserId(200);
        user2.setLoginName("login2");
        user2.setPassword("pwd2");
        user2.setName("user2");
        list.add(user2);
        return list;
    }
}

 

 

主程序 Server.java

 

 

package myserver;
import mytest.thrift.gen.UserService;
import org.apache.thrift.server.TServer;
import org.apache.thrift.server.TSimpleServer;
import org.apache.thrift.transport.TServerSocket;
import org.apache.thrift.transport.TServerTransport;
public class Server {
    public static void main(String[] args) {
        try {
            UserServiceHandler handler = new UserServiceHandler();
            UserService.Processor processor = new UserService.Processor(handler);
            TServerTransport serverTransport = new TServerSocket(9090);
            TServer server = new TSimpleServer(processor, serverTransport);
            // Use this for a multithreaded server
            // server = new TThreadPoolServer(processor, serverTransport);
            System.out.println("Starting the server...");
            server.serve();
        } catch (Exception x) {
            x.printStackTrace();
        }
        System.out.println("done.");
    }
}

 

 

第四步，实现java客户端

 

package myclient;
import java.util.Iterator;
import java.util.List;
import mytest.thrift.gen.User;
import mytest.thrift.gen.UserNotFound;
import mytest.thrift.gen.UserService;
import org.apache.thrift.TException;
import org.apache.thrift.protocol.TBinaryProtocol;
import org.apache.thrift.protocol.TProtocol;
import org.apache.thrift.transport.TSocket;
import org.apache.thrift.transport.TTransport;
public class Client {
    public static void main(String[] args) {
        try {
            TTransport transport = new TSocket("localhost", 9090);
            TProtocol protocol = new TBinaryProtocol(transport);
            UserService.Client client = new UserService.Client(protocol);
            transport.open();
            System.out.println("test1");
            try {
                User user1 = client.getUser("login1");
                System.out.println("name=" + user1.getName());
            } catch (UserNotFound e) {
                System.out.println(e.getMessage());
            }

            System.out.println("test2");
            try {
                User user2 = client.getUser("login10");
                System.out.println("name=" + user2.getName());
            } catch (UserNotFound e) {
                System.out.println(e.getMessage());
            }

            System.out.println("test3");
            List<User> list = client.getUsers();
            Iterator<User> it = list.iterator();
            while(it.hasNext()){
                User u = it.next();
                System.out.println("name=" + u.getName());
            }
            transport.close();
        } catch (TException x) {
            x.printStackTrace();
        }
    }
}

 

第五步，实现python客户端

from mytest.thrift import UserService
from mytest.thrift.ttypes import UserNotFound
from thrift import Thrift
from thrift.transport import TSocket
from thrift.transport import TTransport
from thrift.protocol import TBinaryProtocol
try:
    # Make socket
    transport = TSocket.TSocket('localhost', 9090)
    # Buffering is critical. Raw sockets are very slow
    transport = TTransport.TBufferedTransport(transport)
    # Wrap in a protocol
    protocol = TBinaryProtocol.TBinaryProtocol(transport)
    # Create a client to use the protocol encoder
    client = UserService.Client(protocol)
    # Connect!
    transport.open()
    try:
        user1 = client.getUser("login1")
        print user1.name
    except UserNotFound, io:
        print '%r' % io
    # Close!
    transport.close()
except Thrift.TException, tx:
    print '%s' % (tx.message)