Add the fast db client enablation option

config.example.json

@@ -133,6 +133,8 @@
     ],
     //idle_connection_timeout: Defaults to 60 seconds, the lifetime 
     //of the connection without read or write
-    "idle_connection_timeout": 60
+    "idle_connection_timeout": 60,
+    //enable_fast_db_client: Defaults to false
+    "enable_fast_db_client": false
   }
 }

drogon_ctl/templates/config.csp

@@ -133,6 +133,8 @@
     ],
     //idle_connection_timeout: Defaults to 60 seconds, the lifetime 
     //of the connection without read or write
-    "idle_connection_timeout": 60
+    "idle_connection_timeout": 60,
+    //enable_fast_db_client: Defaults to false
+    "enable_fast_db_client": false
   }
 }

lib/inc/drogon/HttpAppFramework.h

@@ -17,7 +17,7 @@
 #include <drogon/config.h>
 #if USE_ORM
 #include <drogon/orm/DbClient.h>
-#define USE_FAST_CLIENT 0
+#define USE_FAST_CLIENT 1
 #endif
 #include <drogon/utils/Utilities.h>
 #include <drogon/HttpBinder.h>
@@ -187,6 +187,7 @@ class HttpAppFramework : public trantor::NonCopyable
 #if USE_ORM
     virtual orm::DbClientPtr getDbClient(const std::string &name = "default") = 0;
 #if USE_FAST_CLIENT
+    virtual void enableFastDbClient() = 0;
     virtual orm::DbClientPtr getFastDbClient(const std::string &name = "default") = 0;
 #endif
     virtual void createDbClient(const std::string &dbType,

lib/src/ConfigLoader.cc

@@ -228,12 +228,20 @@ static void loadApp(const Json::Value &app)
     //Kick off idle connections
     auto kickOffTimeout = app.get("idle_connection_timeout", 60).asUInt64();
     drogon::app().setIdleConnectionTimeout(kickOffTimeout);
+#if USE_ORM
+#if USE_FAST_CLIENT
+    //Fast db client
+    auto fastDbClient = app.get("enable_fast_db_client", false).asBool();
+    if (fastDbClient)
+        drogon::app().enableFastDbClient();
+#endif
+#endif
 }
 static void loadDbClients(const Json::Value &dbClients)
 {
     if (!dbClients)
         return;
-#if USE_ORM   
+#if USE_ORM
     for (auto const &client : dbClients)
     {
         auto type = client.get("rdbms", "postgresql").asString();

lib/src/HttpAppFrameworkImpl.cc

@@ -283,15 +283,17 @@ void HttpAppFrameworkImpl::run()
     std::vector<std::shared_ptr<EventLoopThread>> loopThreads;
 
     std::vector<trantor::EventLoop *> ioLoops;
-    for (auto const &listener : _listeners)
+
+#ifdef __linux__
+    for (size_t i = 0; i < _threadNum; i++)
     {
         LOG_TRACE << "thread num=" << _threadNum;
-#ifdef __linux__
-        for (size_t i = 0; i < _threadNum; i++)
+        auto loopThreadPtr = std::make_shared<EventLoopThread>("DrogonIoLoop");
+        loopThreadPtr->run();
+        loopThreads.push_back(loopThreadPtr);
+        ioLoops.push_back(loopThreadPtr->getLoop());
+        for (auto const &listener : _listeners)
         {
-            auto loopThreadPtr = std::make_shared<EventLoopThread>("DrogonIoLoop");
-            loopThreadPtr->run();
-            loopThreads.push_back(loopThreadPtr);
             auto serverPtr = std::make_shared<HttpServer>(loopThreadPtr->getLoop(),
                                                           InetAddress(std::get<0>(listener), std::get<1>(listener)), "drogon");
             if (std::get<2>(listener))
@@ -317,9 +319,12 @@ void HttpAppFrameworkImpl::run()
             serverPtr->kickoffIdleConnections(_idleConnectionTimeout);
             serverPtr->start();
             servers.push_back(serverPtr);
-            ioLoops.push_back(serverPtr->getLoop());
         }
+    }
 #else
+    for (auto const &listener : _listeners)
+    {
+        LOG_TRACE << "thread num=" << _threadNum;
         auto loopThreadPtr = std::make_shared<EventLoopThread>("DrogonListeningLoop");
         loopThreadPtr->run();
         loopThreads.push_back(loopThreadPtr);
@@ -364,12 +369,14 @@ void HttpAppFrameworkImpl::run()
             ioLoops.push_back(serverIoLoop);
         }
         servers.push_back(serverPtr);
-#endif
     }
+#endif
+
 #if USE_ORM
 #if USE_FAST_CLIENT
     // Create fast db clients for every io loop
-    createFastDbClient(ioLoops);
+    if (_enableFastDbClient)
+        createFastDbClient(ioLoops);
 #endif
 #endif
     _httpCtrlsRouter.init(ioLoops);

lib/src/HttpAppFrameworkImpl.h

@@ -109,6 +109,10 @@ class HttpAppFrameworkImpl : public HttpAppFramework
 #if USE_ORM
     virtual orm::DbClientPtr getDbClient(const std::string &name = "default") override;
 #if USE_FAST_CLIENT
+    virtual void enableFastDbClient() override
+    {
+        _enableFastDbClient = true;
+    }
     virtual orm::DbClientPtr getFastDbClient(const std::string &name = "default") override;
 #endif
     virtual void createDbClient(const std::string &dbType,
@@ -190,6 +194,7 @@ class HttpAppFrameworkImpl : public HttpAppFramework
     size_t _logfileSize = 100000000;
     bool _useSendfile = true;
     bool _useGzip = true;
+    bool _enableFastDbClient = false;
     int _staticFilesCacheTime = 5;
     std::unordered_map<std::string, std::weak_ptr<HttpResponse>> _staticFilesCache;
     std::mutex _staticFilesCacheMutex;