Progress #14: Restructure API

The beginnings of the chain API is now much closer to the design
described in #14

plugins/chain_api_plugin/chain_api_plugin.cpp

@@ -12,20 +12,6 @@ public:
    chain_api_plugin_impl(database& db)
       : db(db) {}
 
-   void get_info(url_response_callback& cb) {
-      fc::mutable_variant_object response;
-
-      response["head_block_num"] = db.head_block_num();
-      response["head_block_id"] = db.head_block_id();
-      response["head_block_time"] = db.head_block_time();
-      response["head_block_producer"] = db.head_block_producer();
-      response["recent_slots"] = std::bitset<64>(db.get_dynamic_global_properties().recent_slots_filled).to_string();
-      response["participation_rate"] =
-            __builtin_popcountll(db.get_dynamic_global_properties().recent_slots_filled) / 64.0;
-
-      cb(200, fc::json::to_string(response));
-   }
-
    database& db;
 };
 
@@ -37,9 +23,23 @@ chain_api_plugin::~chain_api_plugin(){}
 void chain_api_plugin::set_program_options(options_description&, options_description&) {}
 void chain_api_plugin::plugin_initialize(const variables_map&) {}
 
+#define CALL(api_name, api_handle, api_namespace, call_name) \
+{std::string("/v1/" #api_name "/" #call_name), [this, api_handle](string, string body, url_response_callback cb) { \
+          try { \
+             if (body.empty()) body = "{}"; \
+             auto result = api_handle.call_name(fc::json::from_string(body).as<api_namespace::call_name ## _params>()); \
+             cb(200, fc::json::to_string(result)); \
+          } catch (fc::exception& e) { \
+             cb(500, e.what()); \
+             elog("Exception encountered while processing ${call}: ${e}", ("call", #api_name "." #call_name)("e", e)); \
+          } \
+       }}
+
 void chain_api_plugin::plugin_startup() {
+   auto ro_api = app().get_plugin<chain_plugin>().get_read_only_api();
+
    app().get_plugin<http_plugin>().add_api({
-      {std::string("/v1/chain/get_info"), [this](string, string, url_response_callback cb) {my->get_info(cb);}}
+      CALL(chain, ro_api, chain_apis::read_only, get_info)
    });
 }
 

plugins/chain_plugin/chain_plugin.cpp

@@ -30,6 +30,7 @@ chain_plugin::chain_plugin()
 chain_plugin::~chain_plugin(){}
 
 database& chain_plugin::db() { return my->db; }
+const chain::database& chain_plugin::db() const { return my->db; }
 
 void chain_plugin::set_program_options(options_description& cli, options_description& cfg)
 {
@@ -145,4 +146,18 @@ bool chain_plugin::block_is_on_preferred_chain(const chain::block_id_type& block
    return db().get_block_id_for_num(chain::block_header::num_from_id(block_id)) == block_id;
 }
 
+namespace chain_apis {
+
+read_only::get_info_results read_only::get_info(const read_only::get_info_params&) const {
+   return {
+      db.head_block_num(),
+      db.head_block_id(),
+      db.head_block_time(),
+      db.head_block_producer(),
+      std::bitset<64>(db.get_dynamic_global_properties().recent_slots_filled).to_string(),
+      __builtin_popcountll(db.get_dynamic_global_properties().recent_slots_filled) / 64.0
+   };
 }
+
+} // namespace chain_apis
+} // namespace eos

plugins/chain_plugin/include/eos/chain_plugin/chain_plugin.hpp

@@ -7,29 +7,61 @@ namespace eos {
    using std::unique_ptr;
    using namespace appbase;
 
-   class chain_plugin : public plugin<chain_plugin>
-   {
-      public:
-        APPBASE_PLUGIN_REQUIRES()
+namespace chain_apis {
+struct empty{};
 
-        chain_plugin();
-        virtual ~chain_plugin();
+class read_only {
+   const database& db;
 
-        virtual void set_program_options(options_description& cli, options_description& cfg) override;
+public:
+   read_only(const database& db)
+      : db(db) {}
 
-        void plugin_initialize(const variables_map& options);
-        void plugin_startup();
-        void plugin_shutdown();
+   using get_info_params = empty;
+   struct get_info_results {
+      uint32_t head_block_num;
+      chain::block_id_type head_block_id;
+      fc::time_point_sec head_block_time;
+      chain::producer_id_type head_block_producer;
+      string recent_slots;
+      double participation_rate;
+   };
+   get_info_results get_info(const get_info_params&) const;
+};
+} // namespace chain_apis
 
-        bool accept_block(const chain::signed_block& block, bool currently_syncing);
-        void accept_transaction(const chain::signed_transaction& trx);
+class chain_plugin : public plugin<chain_plugin> {
+public:
+   APPBASE_PLUGIN_REQUIRES()
 
-        bool block_is_on_preferred_chain(const chain::block_id_type& block_id);
+   chain_plugin();
+   virtual ~chain_plugin();
 
-        database& db();
+   virtual void set_program_options(options_description& cli, options_description& cfg) override;
 
-      private:
-        unique_ptr<class chain_plugin_impl> my;
-   };
+   void plugin_initialize(const variables_map& options);
+   void plugin_startup();
+   void plugin_shutdown();
+
+   chain_apis::read_only get_read_only_api() const {
+      return chain_apis::read_only(db());
+   }
+
+   bool accept_block(const chain::signed_block& block, bool currently_syncing);
+   void accept_transaction(const chain::signed_transaction& trx);
+
+   bool block_is_on_preferred_chain(const chain::block_id_type& block_id);
+
+   database& db();
+   const database& db() const;
+
+private:
+   unique_ptr<class chain_plugin_impl> my;
+};
 
 }
+
+FC_REFLECT(eos::chain_apis::empty, )
+FC_REFLECT(eos::chain_apis::read_only::get_info_results,
+           (head_block_num)(head_block_id)(head_block_time)(head_block_producer)
+           (recent_slots)(participation_rate))

plugins/p2p_plugin/CMakeLists.txt

@@ -2,6 +2,7 @@ file(GLOB HEADERS "include/eos/p2p_plugin/*.hpp")
 
 add_library( p2p_plugin
              p2p_plugin.cpp
+             ${HEADERS}
            )
 
 target_link_libraries( p2p_plugin chain_plugin appbase eos_chain eos_utilities eos_net )