TeV

Thin wrapper of boost.asio for creating applications based on asynchronous TCP sockets.

• Based on asio library and therefore gained the same cross-platform ability
• C++ 11 compatible
• Deliberately avoid using std::function<> to reduce overhead of callbacks
• Presents extremely simple interfaces supporting two styles of session definition:

Session Defined with Class

Session Defined with Functions

class Server: public Session{ public: virtual void onConnect (TCPsession& session)override{ doRead(session); } virtual void onDisconnect (TCPsession& session)override{ std::cout << session.getRemoteIP() << ':' << session.getRemotePort() << " disconnected" << std::endl; } virtual void onError(TCPsession& session, const std::string& err, ErrorType)override{ std::cout << err << std::endl; } virtual ~TimeoutServer(){} private: void doRead(TCPsession& session){ session.asyncRead('\0', [](TCPsession& session_){ std::cout << session_.getMessage() << std::endl; doRead(session_); }); } }; int main(){ asio::io_context io_context; unsigned short port = 1701; Service<> srv(port); srv.start([]{return std::make_shared();}); Worker::run(); }

void doRead(TCPsession& session){ session.asyncRead('\0', [](TCPsession& session_){ std::cout << session_.getMessage() << std::endl; doRead(session_); }); } int main(){ asio::io_context io_context; auto session = SessionBuilder<>().onConnect([](TCPsession& session){ doRead(session); }).onDisconnect([](TCPsession& session){ std::cout << session.getRemoteIP() << ':' << session.getRemotePort() << " disconnected" << std::endl; }).onError([](TCPsession& session, const std::string& err, ErrorType){ std::cout << err << std::endl; }).buildFactory(); unsigned short port = 1701; Service<> srv(port); srv.start(session); Worker::run(); }

Examples

• Echo client and server, messages terminated with '\0': echoNulTer
• Echo client and server, messages with header indicating the length: echoHeader
• Echo client and server, session defined by chain of callbacks: builder
• Timeout server: timeout

Integration

As a cmake subproject

As a header-only library

References

TcpSession

TCPsession encapsulated operations to be applied on the socket, including read, write, close, stat etc. This class should not be instantiated, but is passed to user-defined callbacks by reference.

Member functions:

• void asyncRead(std::size_t length, CB&& callback)

  Read length bytes of data from socket, and invoke callback upon finish. The signature of CB should be void (TCPsession&)

• void asyncRead(char token, CB&& callback)

  Read data from socket until token is met, then invoke callback. The signature of CB should be void (TCPsession&)

• void asyncRead(const char* token, CB&& callback)

  Read data from socket until token is met, then invoke callback. The signature of CB should be void (TCPsession&)

• void asyncRead(CF&& completionCondition, CB&& callback)

  Read data from socket until completionCondition returns 0, then invoke callback. The signature of CB should be void (TCPsession&)

• void asyncWrite(const std::string& message, CB&& callback)

  Write message to socket, and invoke callback upon finish. The signature of CB should be void (TCPsession&). message won't be copied, so this reference must stay valid until callback is called.

• void asyncWrite(SharedBuffer bufs, CB&& callback)

  Write content in bufs to socket, and invoke callback upon finish. The signature of CB should be void (TCPsession&). SharedBuffer will manage underlying memory, so no special care need to be paid on lifetime.

• Timer defer(const duration<Rep, Period>& timeout, CB&& callback)

  Invoke callback after timeout. The signature of CB should be void (const std::error_code&).

• Timer expire(const duration<Rep, Period>& timeout)

  Close session after timeout

• Timer expire(const duration<Rep, Period>& timeout, CB&& callback)

  Invoke callback and close session after timeout

• void close()

  Close the session gracefully

• std::string getMessage()

  Get the received message after asyncRead()

• std::string getMessage(std::size_t length)

  Read length bytes of the received message after asyncRead()

• std::string getRemoteIP()

  Get the IP address of the remote host

• unsigned short getRemotePort()

  Get the port of the remote host

TcpService