peerplays-fc/include/fc/json_rpc_connection.hpp
2012-10-26 01:03:01 -04:00

86 lines
2.6 KiB
C++

#pragma once
#include <fc/json.hpp>
#include <fc/iostream.hpp>
#include <fc/future.hpp>
#include <fc/function.hpp>
namespace fc { namespace json {
namespace detail {
struct pending_result : virtual public promise_base {
typedef shared_ptr<pending_result> ptr;
virtual void handle_result( const fc::value& ) = 0;
void handle_error( const fc::string& );
int64_t id;
pending_result::ptr next;
protected:
~pending_result(){}
};
template<typename T>
struct pending_result_impl : virtual public promise<T>, virtual public pending_result {
virtual void handle_result( const fc::value& s ) {
this->set_value( value_cast<T>(s) );
}
protected:
~pending_result_impl(){}
};
template<>
struct pending_result_impl<void> : virtual public promise<void>, virtual public pending_result {
virtual void handle_result( const fc::value& ) {
set_value();
}
protected:
~pending_result_impl(){}
};
}
/**
* This class can be used to communicate via json-rpc over a pair of
* streams.
*
* @note rpc_connection has reference semantics and all 'copies' will
* refer to the same underlying stream.
*/
class rpc_connection {
public:
rpc_connection();
/** note the life of i and o must be longer than rpc_connection's life */
rpc_connection( istream& i, ostream& o );
rpc_connection( rpc_connection&& c );
rpc_connection( const rpc_connection& c );
~rpc_connection();
rpc_connection& operator=(rpc_connection&& m);
rpc_connection& operator=(const rpc_connection& m);
/** note the life of i and o must be longer than rpc_connection's life */
void init( istream& i, ostream& o );
/*
template<typename R >
future<R> invoke( const fc::string& method ) {
auto r = new detail::pending_result_impl<R>();
invoke( detail::pending_result::ptr(r), method, value(make_tuple()) );
return promise<R>::ptr( r, true );
} */
template<typename R, typename Args >
future<R> invoke( const fc::string& method, Args&& a = nullptr )const {
auto r = new detail::pending_result_impl<R>();
slog( "%p", r );
typename promise<R>::ptr rtn( r, true );
invoke( detail::pending_result::ptr(r), method, value(fc::forward<Args>(a)) );
return rtn;
}
private:
void invoke( detail::pending_result::ptr&& p, const fc::string& m, const value& param )const;
class impl;
fc::shared_ptr<class impl> my;
};
} } // fc::json