Allow network broadcast API to forward tx when running a read-only no…

…de. #587

libraries/app/api.cpp

@@ -193,34 +193,68 @@ namespace steemit { namespace app {
     void network_broadcast_api::broadcast_transaction(const signed_transaction& trx)
     {
        trx.validate();
-       FC_ASSERT( !check_max_block_age( _max_block_age ) );
-       _app.chain_database()->push_transaction(trx);
-       _app.p2p_node()->broadcast_transaction(trx);
+
+       if( _app._read_only )
+       {
+          FC_ASSERT( _app._remote_net_api, "Write node RPC not configured properly or non connected." );
+          (*_app._remote_net_api)->broadcast_transaction( trx );
+       }
+       else
+       {
+          FC_ASSERT( !check_max_block_age( _max_block_age ) );
+          _app.chain_database()->push_transaction(trx);
+          _app.p2p_node()->broadcast_transaction(trx);
+       }
     }
+
     fc::variant network_broadcast_api::broadcast_transaction_synchronous(const signed_transaction& trx)
     {
-       promise<fc::variant>::ptr prom( new fc::promise<fc::variant>() );
-       broadcast_transaction_with_callback( [=]( const fc::variant& v ){
-          prom->set_value(v);
-       }, trx );
-       return future<fc::variant>(prom).wait();
+       if( _app._read_only )
+       {
+          FC_ASSERT( _app._remote_net_api, "Write node RPC not configured properly or non connected." );
+          return (*_app._remote_net_api)->broadcast_transaction_synchronous( trx );
+       }
+       else
+       {
+          promise<fc::variant>::ptr prom( new fc::promise<fc::variant>() );
+          broadcast_transaction_with_callback( [=]( const fc::variant& v ){
+             prom->set_value(v);
+          }, trx );
+          return future<fc::variant>(prom).wait();
+       }
     }
 
     void network_broadcast_api::broadcast_block( const signed_block& b )
     {
-       _app.chain_database()->push_block(b);
-       _app.p2p_node()->broadcast( graphene::net::block_message( b ));
+       if( _app._read_only )
+       {
+          FC_ASSERT( _app._remote_net_api, "Write node RPC not configured properly or non connected." );
+          (*_app._remote_net_api)->broadcast_block( b );
+       }
+       else
+       {
+          _app.chain_database()->push_block(b);
+          _app.p2p_node()->broadcast( graphene::net::block_message( b ));
+       }
     }
 
     void network_broadcast_api::broadcast_transaction_with_callback(confirmation_callback cb, const signed_transaction& trx)
     {
-       FC_ASSERT( !check_max_block_age( _max_block_age ) );
-       trx.validate();
-       _callbacks[trx.id()] = cb;
-       _callbacks_expirations[trx.expiration].push_back(trx.id());
+       if( _app._read_only )
+       {
+          FC_ASSERT( _app._remote_net_api, "Write node RPC not configured properly or non connected." );
+          (*_app._remote_net_api)->broadcast_transaction_with_callback( cb, trx );
+       }
+       else
+       {
+          FC_ASSERT( !check_max_block_age( _max_block_age ) );
+          trx.validate();
+          _callbacks[trx.id()] = cb;
+          _callbacks_expirations[trx.expiration].push_back(trx.id());
 
-       _app.chain_database()->push_transaction(trx);
-       _app.p2p_node()->broadcast_transaction(trx);
+          _app.chain_database()->push_transaction(trx);
+          _app.p2p_node()->broadcast_transaction(trx);
+       }
     }
 
     network_node_api::network_node_api( const api_context& a ) : _app( a.app )

libraries/app/application.cpp

@@ -246,6 +246,7 @@ namespace detail {
 
          if( !read_only )
          {
+            _self->_read_only = false;
             ilog( "Starting Steem node in write mode." );
             _max_block_age =_options->at("max-block-age").as<int32_t>();
 
@@ -305,6 +306,22 @@ namespace detail {
          {
             ilog( "Starting Steem node in read mode." );
             _chain_db->open( _data_dir / "blockchain", 0, _shared_file_size, chainbase::database::read_only );
+
+            if( _options->count( "read-forward-rpc" ) )
+            {
+               try
+               {
+                  auto ws_ptr = _self->_client.connect( _options->at( "read-forward-rpc" ).as< string >() );
+                  auto apic = std::make_shared< fc::rpc::websocket_api_connection >( *ws_ptr );
+                  auto login = apic->get_remote_api< login_api >( 1 );
+                  FC_ASSERT( login->login( "", "" ) );
+                  _self->_remote_net_api = login->get_api_by_name( "network_broadcast_api" )->as< network_broadcast_api >();
+               }
+               catch( fc::exception& e )
+               {
+                  wlog( "Error conencting to remote RPC, network api forwarding disabled.", ("e", e.to_detail_string()) );
+               }
+            }
          }
 
          if( _options->count("api-user") )
@@ -886,6 +903,7 @@ void application::set_program_options(boost::program_options::options_descriptio
          ("shared-file-size", bpo::value<string>()->default_value("32G"), "Size of the shared memory file. Default: 32G")
          ("rpc-endpoint", bpo::value<string>()->implicit_value("127.0.0.1:8090"), "Endpoint for websocket RPC to listen on")
          ("rpc-tls-endpoint", bpo::value<string>()->implicit_value("127.0.0.1:8089"), "Endpoint for TLS websocket RPC to listen on")
+         ("read-forward-rpc", bpo::value<string>(), "Endpoint to forward write API calls to for a read node" )
          ("server-pem,p", bpo::value<string>()->implicit_value("server.pem"), "The TLS certificate file for this server")
          ("server-pem-password,P", bpo::value<string>()->implicit_value(""), "Password for this certificate")
          ("api-user", bpo::value< vector<string> >()->composing(), "API user specification, may be specified multiple times")

libraries/app/include/steemit/app/application.hpp

@@ -31,6 +31,7 @@
 
 #include <fc/api.hpp>
 #include <fc/rpc/api_connection.hpp>
+#include <fc/rpc/websocket_api.hpp>
 
 #include <boost/program_options.hpp>
 
@@ -42,6 +43,9 @@ namespace steemit { namespace app {
    class plugin;
    class application;
 
+   class network_broadcast_api;
+   class login_api;
+
    class application
    {
       public:
@@ -117,6 +121,13 @@ namespace steemit { namespace app {
 
          void get_max_block_age( int32_t& result );
 
+         bool _read_only = true;
+         fc::optional< fc::api< network_broadcast_api > > _remote_net_api;
+         fc::optional< fc::api< login_api > > _remote_login;
+         fc::http::websocket_connection_ptr _ws_ptr;
+         std::shared_ptr< fc::rpc::websocket_api_connection > _ws_apic;
+         fc::http::websocket_client _client;
+
       private:
          std::shared_ptr<detail::application_impl> my;