RPC框架之Thrift简单使用

前言

Thrift是一个可以跨平台，跨语言的RPC(远程过程调用)框架，通过IDL(接口描述语言)来定义数据类型和接口，相当于Protobuf和gRPC的结合体。Thrift最开始由Facebook开源，后来贡献给了Apache。

下载编译器

官网，这里我们下载windows版本的编译器thrift-0.16.0.exe。

定义thrift文件

namespace java com.imooc.sourcecode.java.google.thrift.test1

typedef i16 short
typedef i32 int
typedef i64 long
typedef bool boolean
typedef string String

struct Person {
  1: optional String username
  2: optional int age
  3: optional boolean married
}

exception DataException {
  1: optional String message
  2: optional String callStack
  3: optional String date
}

service PersonService {
  Person getPersonByUsername(1: required String username) throws (1: DataException dataException),
  void savePerson(1: required Person person) throws (1: DataException dataException),
}

namespace 定义包名，类似ProtoBuf的java_package。
typedef 定义类型的别名。
optional 表示当前字段可选，非必填。
1: optional String message 每个字段需要有一个唯一的号码，必须大于0。
exception 定义异常，可以看做Java中的异常。
service 定义服务，可以看做Java中的接口。
struct 可以看做一个Java类，类似ProtoBuf的message。

Java处理

添加maven依赖

<dependency>
  <groupId>org.apache.thrift</groupId>
  <artifactId>libthrift</artifactId>
  <version>0.16.0</version>
</dependency>

根据thrift文件创建Java数据类型和接口代码

thrift -out $DST_DIR --gen java $SRC_DIR/data.proto

-out表示生成代码的路径，java表示生成Java语言的代码，实际命令为

.\thrift-0.16.0.exe -out D:\java\code_resp\github_resp\source_code\src\main\java --gen java D:\java\code_resp\github_resp\source_code\src\main\java\com\imooc\sourcecode\java\google\thrift\test1\data.thrift

-out值不要包含具体的包路径，thrift文件中已经配置了。

序列化和反序列化

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import org.apache.thrift.TDeserializer;
import org.apache.thrift.TSerializer;
import org.apache.thrift.protocol.TCompactProtocol.Factory;

public class TestSerialize {

  public static void main(String[] args) throws Exception {
    testSerialize();
    testDeserialize();
  }

  private static void testSerialize() throws Exception {
    Person person = new Person();
    person.setUsername("李四");
    person.setAge(23);
    person.setMarried(true);
    TSerializer serializer = new TSerializer(new Factory());
    byte[] bytes = serializer.serialize(person);
    new ByteArrayInputStream(bytes)
        .transferTo(new FileOutputStream("D:/testjar/thrift_java_serialize_person"));
  }

  private static void testDeserialize() throws Exception {
    TDeserializer deserializer = new TDeserializer(new Factory());
    Person person = new Person();
    ByteArrayOutputStream output = new ByteArrayOutputStream();
    new FileInputStream("D:/testjar/thrift_java_serialize_person").transferTo(output);
    deserializer.deserialize(person, output.toByteArray());
    System.out.println(person);
  }
}

序列化和反序列化要使用相同的TProtocolFactory类型。

服务器端代码

import com.imooc.sourcecode.java.google.thrift.test1.PersonService.Processor;
import org.apache.thrift.TException;
import org.apache.thrift.TProcessorFactory;
import org.apache.thrift.protocol.TCompactProtocol;
import org.apache.thrift.server.THsHaServer;
import org.apache.thrift.server.THsHaServer.Args;
import org.apache.thrift.transport.TNonblockingServerSocket;
import org.apache.thrift.transport.TTransportException;
import org.apache.thrift.transport.layered.TFramedTransport;

public class MyServer {

  public static void main(String[] args) throws TTransportException {
    TNonblockingServerSocket serverSocket = new TNonblockingServerSocket(8883);
    THsHaServer.Args serverArgs = new Args(serverSocket).minWorkerThreads(2).maxWorkerThreads(4);
    Processor<PersonServiceImpl> processor = new Processor<>(new PersonServiceImpl());
    serverArgs.protocolFactory(new TCompactProtocol.Factory());
    serverArgs.transportFactory(new TFramedTransport.Factory());
    serverArgs.processorFactory(new TProcessorFactory(processor));
    System.out.println("Server start");
    THsHaServer server = new THsHaServer(serverArgs);
    server.serve();
  }

  public static class PersonServiceImpl implements PersonService.Iface {

    @Override
    public Person getPersonByUsername(String username) throws DataException, TException {
      System.out.println("param: " + username);
      Person person = new Person();
      person.setUsername(username);
      person.setAge(23);
      person.setMarried(true);
      return person;
    }

    @Override
    public void savePerson(Person person) throws DataException, TException {
      System.out.println("param: " + person);
      System.out.println(person);
    }
  }

}

定义PersonServiceImpl实现类，来处理客户端请求。

客户端代码

import com.imooc.sourcecode.java.google.thrift.test1.PersonService.Client;
import org.apache.thrift.TException;
import org.apache.thrift.protocol.TCompactProtocol;
import org.apache.thrift.transport.TSocket;
import org.apache.thrift.transport.layered.TFramedTransport;

public class MyClient {

  public static void main(String[] args) throws TException {
    TFramedTransport transport = new TFramedTransport(new TSocket("localhost", 8883));

    TCompactProtocol protocol = new TCompactProtocol(transport);
    Client client = new Client(protocol);
    transport.open();
    Person queryPerson = client.getPersonByUsername("张三");
    System.out.println(queryPerson);
    Person savePerson = new Person();
    savePerson.setUsername("李四");
    savePerson.setAge(21);
    savePerson.setMarried(false);
    client.savePerson(savePerson);
    transport.close();
  }

}

可以看到，客户端调用服务器端接口就像调用本地方法一样简单。

Python处理

安装依赖

pip install thrift

PyCharm中可以这样安装

根据thrift文件创建Python数据类型和接口代码

thrift -out $DST_DIR --gen py $SRC_DIR/data.proto

-out表示生成代码的路径，py表示生成Python语言的代码，实际命令为

.\thrift-0.16.0.exe -out D:\java\code_resp\PycharmProjects\test_protobuf\testthrift --gen py D:\java\code_resp\PycharmProjects\test_protobuf\testthrift\data.thrift

代码结构如下，data目录为生成的目录，包含数据类型和服务接口。

序列化和反序列化

from data import ttypes
from thrift import TSerialization
from thrift.protocol import TCompactProtocol

def test_serialize():
    p = ttypes.Person()
    p.username = "小明"
    p.age = 27
    p.married = False
    bytes = TSerialization.serialize(p,TCompactProtocol.TCompactProtocolFactory())
    with open("D:/testjar/thrift_python_serialize_person", "wb") as f:
        f.write(bytes)
    return

def test_deserialize():
    with open("D:/testjar/thrift_python_serialize_person", "rb") as rf:
        bytes_read = rf.read()
        p = ttypes.Person()
        TSerialization.deserialize(p, bytes_read, TCompactProtocol.TCompactProtocolFactory())
        print(p)
    return


if __name__ == '__main__':
    test_deserialize()
    pass

服务器端代码

from PersonServiceImpl import PersonServiceImpl
from data import PersonService
from thrift.protocol import TCompactProtocol
from thrift.server import TServer
from thrift.transport import TSocket
from thrift.transport import TTransport


def test():
    # Make socket
    personServiceImpl = PersonServiceImpl()
    processor = PersonService.Processor(personServiceImpl)
    serverSocket = TSocket.TServerSocket(port=8883)
    transportFactory = TTransport.TFramedTransportFactory()
    protocolFactory = TCompactProtocol.TCompactProtocolFactory()
    server = TServer.TThreadPoolServer(processor, serverSocket, transportFactory, protocolFactory)
    server.serve()
    pass


if __name__ == '__main__':
    test()
    pass

客户端代码

from thrift.transport import TSocket
from thrift.transport import TTransport
from thrift.protocol import TCompactProtocol
from data import PersonService


def test():
    # Make socket
    transport = TSocket.TSocket('localhost', 8883)
    # Buffering is critical. Raw sockets are very slow
    transport = TTransport.TFramedTransport(transport)
    # Wrap in a protocol
    protocol = TCompactProtocol.TCompactProtocol(transport)
    # Create a client to use the protocol encoder
    client = PersonService.Client(protocol)
    # Connect!
    transport.open()
    p = client.getPersonByUsername("李四")
    print(p)
    pass

if __name__ == '__main__':
    test()
    pass

总结

更多Thrift相关用法，请查看官方文档。

参考

Apache Thrift
如何给老婆解释什么是RPC
Thrift 简易入门与实战
【Thrift】Thrift的那些服务模型
Thrift（一）：快速入门