C++ Tutorial


Introduction

All Apache Thrift tutorials require that you have:

  1. Built and installed the Apache Thrift Compiler and Libraries, see Building from source for more details.
  2. Generated the tutorial.thrift and shared.thrift files as discussed here.

    thrift -r --gen cpp tutorial.thrift
    
  3. Followed all prerequisites listed below.

Prerequisites

Client

#include <iostream>

#include <thrift/protocol/TBinaryProtocol.h>
#include <thrift/transport/TSocket.h>
#include <thrift/transport/TTransportUtils.h>

#include "../gen-cpp/Calculator.h"

using namespace std;
using namespace apache::thrift;
using namespace apache::thrift::protocol;
using namespace apache::thrift::transport;

using namespace tutorial;
using namespace shared;

int main() {
  boost::shared_ptr<TTransport> socket(new TSocket("localhost", 9090));
  boost::shared_ptr<TTransport> transport(new TBufferedTransport(socket));
  boost::shared_ptr<TProtocol> protocol(new TBinaryProtocol(transport));
  CalculatorClient client(protocol);

  try {
    transport->open();

    client.ping();
    cout << "ping()" << endl;

    cout << "1 + 1 = " << client.add(1, 1) << endl;

    Work work;
    work.op = Operation::DIVIDE;
    work.num1 = 1;
    work.num2 = 0;

    try {
      client.calculate(1, work);
      cout << "Whoa? We can divide by zero!" << endl;
    } catch (InvalidOperation& io) {
      cout << "InvalidOperation: " << io.why << endl;
      // or using generated operator<<: cout << io << endl;
      // or by using std::exception native method what(): cout << io.what() << endl;
    }

    work.op = Operation::SUBTRACT;
    work.num1 = 15;
    work.num2 = 10;
    int32_t diff = client.calculate(1, work);
    cout << "15 - 10 = " << diff << endl;

    // Note that C++ uses return by reference for complex types to avoid
    // costly copy construction
    SharedStruct ss;
    client.getStruct(ss, 1);
    cout << "Received log: " << ss << endl;

    transport->close();
  } catch (TException& tx) {
    cout << "ERROR: " << tx.what() << endl;
  }
}

Server

#include <thrift/concurrency/ThreadManager.h>
#include <thrift/concurrency/PlatformThreadFactory.h>
#include <thrift/protocol/TBinaryProtocol.h>
#include <thrift/server/TSimpleServer.h>
#include <thrift/server/TThreadPoolServer.h>
#include <thrift/server/TThreadedServer.h>
#include <thrift/transport/TServerSocket.h>
#include <thrift/transport/TSocket.h>
#include <thrift/transport/TTransportUtils.h>
#include <thrift/TToString.h>

#include <boost/make_shared.hpp>

#include <iostream>
#include <stdexcept>
#include <sstream>

#include "../gen-cpp/Calculator.h"

using namespace std;
using namespace apache::thrift;
using namespace apache::thrift::concurrency;
using namespace apache::thrift::protocol;
using namespace apache::thrift::transport;
using namespace apache::thrift::server;

using namespace tutorial;
using namespace shared;

class CalculatorHandler : public CalculatorIf {
public:
  CalculatorHandler() {}

  void ping() { cout << "ping()" << endl; }

  int32_t add(const int32_t n1, const int32_t n2) {
    cout << "add(" << n1 << ", " << n2 << ")" << endl;
    return n1 + n2;
  }

  int32_t calculate(const int32_t logid, const Work& work) {
    cout << "calculate(" << logid << ", " << work << ")" << endl;
    int32_t val;

    switch (work.op) {
    case Operation::ADD:
      val = work.num1 + work.num2;
      break;
    case Operation::SUBTRACT:
      val = work.num1 - work.num2;
      break;
    case Operation::MULTIPLY:
      val = work.num1 * work.num2;
      break;
    case Operation::DIVIDE:
      if (work.num2 == 0) {
        InvalidOperation io;
        io.whatOp = work.op;
        io.why = "Cannot divide by 0";
        throw io;
      }
      val = work.num1 / work.num2;
      break;
    default:
      InvalidOperation io;
      io.whatOp = work.op;
      io.why = "Invalid Operation";
      throw io;
    }

    SharedStruct ss;
    ss.key = logid;
    ss.value = to_string(val);

    log[logid] = ss;

    return val;
  }

  void getStruct(SharedStruct& ret, const int32_t logid) {
    cout << "getStruct(" << logid << ")" << endl;
    ret = log[logid];
  }

  void zip() { cout << "zip()" << endl; }

protected:
  map<int32_t, SharedStruct> log;
};

/*
  CalculatorIfFactory is code generated.
  CalculatorCloneFactory is useful for getting access to the server side of the
  transport.  It is also useful for making per-connection state.  Without this
  CloneFactory, all connections will end up sharing the same handler instance.
*/
class CalculatorCloneFactory : virtual public CalculatorIfFactory {
 public:
  virtual ~CalculatorCloneFactory() {}
  virtual CalculatorIf* getHandler(const ::apache::thrift::TConnectionInfo& connInfo)
  {
    boost::shared_ptr<TSocket> sock = boost::dynamic_pointer_cast<TSocket>(connInfo.transport);
    cout << "Incoming connection\n";
    cout << "\tSocketInfo: "  << sock->getSocketInfo() << "\n";
    cout << "\tPeerHost: "    << sock->getPeerHost() << "\n";
    cout << "\tPeerAddress: " << sock->getPeerAddress() << "\n";
    cout << "\tPeerPort: "    << sock->getPeerPort() << "\n";
    return new CalculatorHandler;
  }
  virtual void releaseHandler( ::shared::SharedServiceIf* handler) {
    delete handler;
  }
};

int main() {
  TThreadedServer server(
    boost::make_shared<CalculatorProcessorFactory>(boost::make_shared<CalculatorCloneFactory>()),
    boost::make_shared<TServerSocket>(9090), //port
    boost::make_shared<TBufferedTransportFactory>(),
    boost::make_shared<TBinaryProtocolFactory>());

  /*
  // if you don't need per-connection state, do the following instead
  TThreadedServer server(
    boost::make_shared<CalculatorProcessor>(boost::make_shared<CalculatorHandler>()),
    boost::make_shared<TServerSocket>(9090), //port
    boost::make_shared<TBufferedTransportFactory>(),
    boost::make_shared<TBinaryProtocolFactory>());
  */

  /**
   * Here are some alternate server types...

Additional Information

Example ThreadPool Server

  virtual CalculatorIf* getHandler(const ::apache::thrift::TConnectionInfo& connInfo)
  {
    boost::shared_ptr<TSocket> sock = boost::dynamic_pointer_cast<TSocket>(connInfo.transport);
    cout << "Incoming connection\n";
    cout << "\tSocketInfo: "  << sock->getSocketInfo() << "\n";
    cout << "\tPeerHost: "    << sock->getPeerHost() << "\n";
    cout << "\tPeerAddress: " << sock->getPeerAddress() << "\n";
    cout << "\tPeerPort: "    << sock->getPeerPort() << "\n";
    return new CalculatorHandler;
  }
  virtual void releaseHandler( ::shared::SharedServiceIf* handler) {
    delete handler;
  }