Adding cli wrapper to expose APIs to the CLI

include/fc/rpc/cli.hpp

@@ -0,0 +1,75 @@
+#pragma once
+#include <fc/io/stdio.hpp>
+#include <fc/io/json.hpp>
+#include <fc/io/buffered_iostream.hpp>
+#include <fc/io/sstream.hpp>
+#include <fc/thread/thread.hpp>
+
+namespace fc { namespace rpc {
+
+   /**
+    *  Provides a simple wrapper for RPC calls to a given interface.
+    */
+   class cli : public api_connection
+   {
+      public:
+         virtual variant send_call( api_id_type api_id, string method_name, variants args = variants() ) 
+         {
+            FC_ASSERT(false);
+         }
+         virtual variant send_callback( uint64_t callback_id, variants args = variants() ) 
+         {
+            FC_ASSERT(false);
+         }
+         virtual void    send_notice( uint64_t callback_id, variants args = variants() ) 
+         {
+            FC_ASSERT(false);
+         }
+
+         void start()
+         {
+            _run_complete = fc::async( [&](){ run(); } );
+         }
+         void stop()
+         {
+            _run_complete.cancel();
+            _run_complete.wait();
+         }
+         void format_result( const string& method, std::function<string(variant,const variants&)> formatter)
+         {
+            _result_formatters[method] = formatter;
+         }
+      private:
+         void run()
+         {
+            while( !_run_complete.canceled() )
+            {
+               std::cout << ">>> ";
+               std::string line;
+               fc::getline( fc::cin, line );
+               auto line_stream = std::make_shared<fc::stringstream>( line );
+               buffered_istream bstream(line_stream);
+               fc::variant  method;
+               fc::variants args;
+
+               method = fc::json::from_stream( bstream );
+               while( true )
+               {
+                  try {
+                     args.push_back( fc::json::from_stream( bstream ) );
+                  } catch ( const fc::eof_exception& eof ){}
+               }
+               auto result = receive_call( 0, method.get_string(), args );
+               auto itr = _result_formatters.find( method.get_string() );
+               if( itr == _result_formatters.end() )
+               {
+                  std::cout << fc::json::to_pretty_string( result ) << "\n";
+               }
+               else
+                  std::cout << itr->second( result, args ) << "\n";
+            }
+         }
+         std::map<string,std::function<string(variant,const variants&)> > _result_formatters;
+         fc::future<void> _run_complete;
+   };
+} }