Added flatbuffers support to the PluginBase::Error

This changes BREAKS osrm.

CMakeLists.txt

@@ -440,6 +440,8 @@ set(VTZERO_INCLUDE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/third_party/vtzero/include")
 include_directories(SYSTEM ${VTZERO_INCLUDE_DIR})
 
 set(FLATBUFFERS_SRC_DIR "${CMAKE_CURRENT_SOURCE_DIR}/third_party/flatbuffers")
+set(FLATBUFFERS_INCLUDE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/third_party/flatbuffers/include")
+include_directories(${FLATBUFFERS_INCLUDE_DIR})
 add_subdirectory(${FLATBUFFERS_SRC_DIR}
         ${CMAKE_CURRENT_BINARY_DIR}/flatbuffers-build
         EXCLUDE_FROM_ALL)

include/engine/api/base_result.hpp

@@ -1,6 +1,7 @@
 #ifndef ENGINE_API_BASE_RESULT_HPP
 #define ENGINE_API_BASE_RESULT_HPP
 
+#include <flatbuffers/flatbuffers.h>
 #include <mapbox/variant.hpp>
 
 #include <string>
@@ -13,7 +14,7 @@ namespace engine
 {
 namespace api
 {
-    using ResultT = mapbox::util::variant<util::json::Object, std::string>;
+    using ResultT = mapbox::util::variant<util::json::Object, std::string, flatbuffers::FlatBufferBuilder>;
 } // ns api
 } // ns engine
 } // ns osrm

include/engine/plugins/plugin_base.hpp

@@ -3,6 +3,7 @@
 
 #include "engine/api/base_parameters.hpp"
 #include "engine/api/base_result.hpp"
+#include "engine/api/flatbuffers/fbresult_generated.h"
 #include "engine/datafacade/datafacade_base.hpp"
 #include "engine/phantom_node.hpp"
 #include "engine/routing_algorithms.hpp"
@@ -63,14 +64,32 @@ class BasePlugin
         return false;
     }
 
+    struct ErrorRenderer {
+        std::string code;
+        std::string message;
+
+        ErrorRenderer(std::string code, std::string message) : code(std::move(code)), message(std::move(message)) {};
+
+        void operator()(util::json::Object& json_result) {
+            json_result.values["code"] = code;
+            json_result.values["message"] = message;
+        };
+        void operator()(flatbuffers::FlatBufferBuilder& fb_result) {
+            osrm::engine::api::fbresult::FBResultBuilder error(fb_result);
+            error.add_code(fb_result.CreateString(code));
+            error.add_message(fb_result.CreateString(message));
+            fb_result.Finish(error.Finish());
+        };
+        void operator()(std::string& str_result) {
+            str_result = str(boost::format("code=%1% message=%2%") % code % message);
+        };
+    };
+
     Status Error(const std::string &code,
                  const std::string &message,
                  osrm::engine::api::ResultT &result) const
     {
-        result = util::json::Object();
+        mapbox::util::apply_visitor(ErrorRenderer(code, message), result);
-        auto& json_result = result.get<util::json::Object>();
-        json_result.values["code"] = code;
-        json_result.values["message"] = message;
         return Status::Error;
     }
 

src/engine/plugins/table.cpp

@@ -33,7 +33,6 @@ Status TablePlugin::HandleRequest(const RoutingAlgorithmsInterface &algorithms,
                                   const api::TableParameters &params,
                                   osrm::engine::api::ResultT &result) const
 {
-    auto& json_result = result.get<util::json::Object>();
     if (!algorithms.HasManyToManySearch())
     {
         return Error("NotImplemented",
@@ -155,6 +154,7 @@ Status TablePlugin::HandleRequest(const RoutingAlgorithmsInterface &algorithms,
     }
 
     api::TableAPI table_api{facade, params};
+    auto& json_result = result.get<util::json::Object>();
     table_api.MakeResponse(result_tables_pair, snapped_phantoms, estimated_pairs, json_result);
 
     return Status::Ok;

src/server/service/table_service.cpp

@@ -97,6 +97,12 @@ TableService::RunQuery(std::size_t prefix_length, std::string &query, osrm::engi
     }
     BOOST_ASSERT(parameters->IsValid());
 
+    if (parameters->format)
+    {
+        if (parameters->format == engine::api::BaseParameters::OutputFormatType::FLATBUFFERS) {
+            result = flatbuffers::FlatBufferBuilder();
+        }
+    }
     return BaseService::routing_machine.Table(*parameters, result);
 }
 }