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Revision 34 as of 2012-08-13 18:37:38
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Editor: ChrisLansman
Comment: the .o compilation needed these -D or else we received compilation errors for ‘ntohl' was not declared in this scope.
Revision 35 as of 2012-08-13 18:38:13
Size: 7777
Editor: ChrisLansman
Comment: the .o compilation needed these -D or else we received compilation errors for ‘ntohl' was not declared in this scope.
Deletions are marked like this. Additions are marked like this.
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 g++ -Wall -DHAVE_INTTYPES_H -DHAVE_NETINET_IN_H $(INC) -c $< -o $@  $(CXX) -Wall -DHAVE_INTTYPES_H -DHAVE_NETINET_IN_H $(INC) -c $< -o $@

Getting started

The first thing you need to know is that the C++ code generated by Thrift compiles only on Unix based systems, although some success has been reported using Cygwin on Win32 in ThriftInstallationWin32.

Requirements

Make sure that your system meets the requirements as noted in ThriftRequirements

  • Thrift library files
  • Thrift header files.

Installing the Thrift library

Installing the Thrift library is trivial to link with the generated code.

  1. Download a snapshot of Thrift and extract if you haven't done so already - Direct Link

  2. Navigate to lib/cpp using the terminal of your choice

  3. Run  make to compile

  4. Run  make install to install the library. Your user needs root permissions.

Generating the server code

In this example we use an imaginary file called your_thrift_file.thrift:

#!/usr/local/bin/thrift --gen cpp

namespace cpp Test

service Something {
  i32 ping()
}

Now run:

thrift --gen cpp your_thrift_file.thrift

Exploring the generated code - The Server

The generated code should be under the gen-cpp directory. You will see a number of generated C++ and header files along with an automatically generated server skeleton code (in bold).

  • Something.cpp
  • Something.h
  • Something_server.skeleton.cpp

  • your_thrift_file_constants.cpp
  • your_thrift_file_constants.h
  • your_thrift_file_types.cpp
  • your_thrift_file_types.h

Implementing the Server

Copy the generated server skeleton to a file named Something_server.cpp and keep the original:

cp Something_server.skeleton.cpp Something_server.cpp

When this server is run in console it prints "ping" on the console window each time the function is called from a client.

Here's the autogenerated skeleton file to illustrate how to write a server: Something_server.cpp

   1 #include "Something.h"
   2 #include <protocol/TBinaryProtocol.h>
   3 #include <server/TSimpleServer.h>
   4 #include <transport/TServerSocket.h>
   5 #include <transport/TTransportUtils.h>
   6 
   7 using namespace apache::thrift;
   8 using namespace apache::thrift::protocol;
   9 using namespace apache::thrift::transport;
  10 using namespace apache::thrift::server;
  11 
  12 using boost::shared_ptr;
  13 
  14 using namespace Test;
  15 
  16 class SomethingHandler : virtual public SomethingIf {
  17  public:
  18   SomethingHandler() {
  19    // Your initialization goes here
  20   }
  21 
  22   int32_t ping() {
  23    // Your implementation goes here
  24     printf("ping\n");
  25   }
  26 
  27 };
  28 
  29 int main(int argc, char **argv) {
  30   int port = 9090;
  31   shared_ptr<SomethingHandler> handler(new SomethingHandler());
  32   shared_ptr<TProcessor> processor(new SomethingProcessor(handler));
  33   shared_ptr<TServerTransport> serverTransport(new TServerSocket(port));
  34   shared_ptr<TTransportFactory> transportFactory(new TBufferedTransportFactory());
  35   shared_ptr<TProtocolFactory> protocolFactory(new TBinaryProtocolFactory());
  36 
  37   TSimpleServer server(processor, serverTransport, transportFactory, protocolFactory);
  38   server.serve();
  39   return 0;
  40 }

Compiling/Building the server

To quickly build a binary using a single command use:

g++ -DHAVE_INTTYPES_H -DHAVE_NETINET_IN_H -Wall -I/usr/local/include/thrift *.cpp -L/usr/local/lib -lthrift -o something

Compiling

You need to point your compiler to the thrift include path (CXX flag:  -I/usr/local/include/thrift)

g++ -Wall -I/usr/local/include/thrift -c Something.cpp -o something.o
g++ -Wall -I/usr/local/include/thrift -c Something_server.cpp -o server.o
g++ -Wall -I/usr/local/include/thrift -c your_thrift_file_constants.cpp -o constants.o
g++ -Wall -I/usr/local/include/thrift -c your_thrift_file_types.cpp -o types.o

Linking

You need to point your linker to the thrift library. (Linker flag:  -lthrift  or  -l/usr/local/lib/libthrift.so )

g++ -L/usr/local/lib *.o -o Something_server -lthrift

Writing the client code

thrift does not auto generate a client interface, so you have to create the file.

   1 #include "Something.h"  // As an example
   2 
   3 #include <transport/TSocket.h>
   4 #include <transport/TBufferTransports.h>
   5 #include <protocol/TBinaryProtocol.h>
   6 
   7 using namespace apache::thrift;
   8 using namespace apache::thrift::protocol;
   9 using namespace apache::thrift::transport;
  10 
  11 using namespace Test;
  12 
  13 int main(int argc, char **argv) {
  14   boost::shared_ptr<TSocket> socket(new TSocket("localhost", 9090));
  15   boost::shared_ptr<TTransport> transport(new TBufferedTransport(socket));
  16   boost::shared_ptr<TProtocol> protocol(new TBinaryProtocol(transport));
  17 
  18   SomethingClient client(protocol);
  19   transport->open();
  20   client.ping();
  21   transport->close();
  22 
  23   return 0;
  24 }

Compiling

g++ -Wall -I/usr/local/include/thrift -c Something_client.cpp -o client.o

Linking

g++ -L/usr/local/lib client.o Something.o constants.o types.o -o Something_client -lthrift

Compiling/Building everything with Makefile

GEN_SRC := Something.cpp your_thrift_file_constants.cpp your_thrift_file_types.cpp
GEN_OBJ := $(patsubst %.cpp,%.o, $(GEN_SRC))

THRIFT_DIR := /usr/local/include/thrift
BOOST_DIR := /usr/local/include

INC := -I$(THRIFT_DIR) -I$(BOOST_DIR)

.PHONY: all clean

all: something_server something_client

%.o: %.cpp
        $(CXX) -Wall -DHAVE_INTTYPES_H -DHAVE_NETINET_IN_H $(INC) -c $< -o $@

something_server: Something_server.o $(GEN_OBJ)
        $(CXX) $^ -o $@ -L/usr/local/lib -lthrift 

something_client: Something_client.o $(GEN_OBJ)
        $(CXX) $^ -o $@ -L/usr/local/lib -lthrift 

clean:
        $(RM) *.o something_server something_client

Appendix: About TNonblockingServer

If you are writing an application that will serve a lot of connection (like php front end calling thrift service), you'd better use TNonblockingServer. TNonblockingServer can accept a lot of connections while throttling the processor threads using a pool.

* TNonblockingServer with a thread pool is the c++ alternative of the JAVA THsHaServer; * TNonblockingServer withOUT a thread pool is the c++ alternative of the JAVA TNonblockingServer;

Server code with thread pool:

    shared_ptr<TProcessor> processor(new SomethingProcessor(handler));
    shared_ptr<TProtocolFactory> protocolFactory(new TBinaryProtocolFactory());

    // using thread pool with maximum 15 threads to handle incoming requests
    shared_ptr<ThreadManager> threadManager = ThreadManager::newSimpleThreadManager(15);
    shared_ptr<PosixThreadFactory> threadFactory = shared_ptr<PosixThreadFactory>(new PosixThreadFactory());
    threadManager->threadFactory(threadFactory);
    threadManager->start();
    TNonblockingServer server(processor, protocolFactory, 8888, threadManager);
    server.serve();

    // ...

C++ client code (you have to use TFramedTransport here):

    boost::shared_ptr<TSocket> socket(new TSocket("localhost", 8888));
    boost::shared_ptr<TTransport> transport(new TFramedTransport(socket));
    boost::shared_ptr<TProtocol> protocol(new TBinaryProtocol(transport));

    SomethingClient client(protocol);
    transport->open();
    // do something here...
    transport->close();

PHP client code (you have to use TFramedTransport here):

    $transport = new TFramedTransport(new TSocket("localhost", 8888));
    $transport->open();
    $protocol = new TBinaryProtocol($transport);
    $client= new SomethingClient($protocol, $protocol);
    // do something here...
    transport->close();

ThriftUsageC++ (last edited 2012-08-13 18:38:13 by ChrisLansman)