thrift之Hello

Thrift是一个开发跨语言服务的软件框架。编写thrift文件，通过自带的代码生成引擎即可生成各种语言(C++，Java，Python，PHP，Ruby，Erlang，C#等)的对应代码，下面以最经典的hello为例讲述，如何通过thrift编写跨语言的RPC程序：
1编写thrift文件，保存为hello.thrift：

service Hello
{
    void Hello()
}

2生成cpp和py框架文件
在hello.thrift文件所在目录执行：
thrift -r –gen cpp hello.thrift
thrift -r –gen py hello.thrift
会在当前目录下面产生两个文件夹，分别为gen-cpp和gen-py，
3编写cpp服务器端代码，拷贝gen-cpp目录中的Hello_server.skeleton.cpp到当前目录，重命名为CppServer.cpp，修改如下：

#include “Hello.h”

#include <protocol/TBinaryProtocol.h>

#include <server/TSimpleServer.h>

#include <transport/TServerSocket.h>

#include <transport/TBufferTransports.h>

using namespace ::apache::thrift;
using namespace ::apache::thrift::protocol;
using namespace ::apache::thrift::transport;
using namespace ::apache::thrift::server;
using boost::shared_ptr;
class HelloHandler : virtual public HelloIf
{
public:
HelloHandler()
{
// Your initialization goes here
}
void Hello()
{
// Your implementation goes here
printf(“Hello,Thrift/n”);
}
};
int main(int argc, char **argv)
{
int port = 9090;
shared_ptr handler(new HelloHandler());
shared_ptr processor(new HelloProcessor(handler));
shared_ptr serverTransport(new TServerSocket(port));
shared_ptr transportFactory(new TBufferedTransportFactory());
shared_ptr protocolFactory(new TBinaryProtocolFactory());
TSimpleServer server(processor, serverTransport, transportFactory, protocolFactory);

server.serve();

return 0;

}
4编写python客户端代码，PythonClient.py如下：

#!/usr/bin/env python
import sys
sys.path.append(‘./gen-py’)
from hello import Hello
from hello.ttypes import *
from thrift import Thrift
from thrift.transport import TSocket
from thrift.transport import TTransport
from thrift.protocol import TBinaryProtocol

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 = Hello.Client(protocol)

Connect!

transport.open()

Call Server services

client.Hello()
5编写cpp端Makefile如下：

BOOST_DIR = /usr/local/include/boost/
THRIFT_DIR = /usr/local/include/thrift
LIB_DIR = /usr/local/lib
GEN_SRC = ./gen-cpp/hello_types.cpp ./gen-cpp/Hello.cpp
default: server
server: CppServer.cpp
g++ -o CppServer -I${THRIFT_DIR} -I${BOOST_DIR} -I./gen-cpp -L${LIB_DIR} -lthrift CppServer.cpp ${GEN_SRC}
clean:
$(RM) -r CppServer

6编译cpp端，直接make即可生成相应的可执行文件，python端可以直接运行。

至此一个最简单的跨语言PRC程序即完成了，很简单吧。