Implement setup_proxy_connection method for SSLClient and refactor proxy handling in open_stream

httplib.h

@@ -2191,6 +2191,10 @@ protected:
 
   virtual bool create_and_connect_socket(Socket &socket, Error &error);
   virtual bool ensure_socket_connection(Socket &socket, Error &error);
+  virtual bool setup_proxy_connection(
+      Socket &socket,
+      std::chrono::time_point<std::chrono::steady_clock> start_time,
+      Response &res, bool &success, Error &error);
 
   // All of:
   //   shutdown_ssl
@@ -2717,6 +2721,10 @@ private:
                  std::function<bool(Stream &strm)> callback) override;
   bool is_ssl() const override;
 
+  bool setup_proxy_connection(
+      Socket &socket,
+      std::chrono::time_point<std::chrono::steady_clock> start_time,
+      Response &res, bool &success, Error &error) override;
   bool connect_with_proxy(
       Socket &sock,
       std::chrono::time_point<std::chrono::steady_clock> start_time,
@@ -12140,6 +12148,13 @@ inline bool ClientImpl::ensure_socket_connection(Socket &socket, Error &error) {
   return create_and_connect_socket(socket, error);
 }
 
+inline bool ClientImpl::setup_proxy_connection(
+    Socket & /*socket*/,
+    std::chrono::time_point<std::chrono::steady_clock> /*start_time*/,
+    Response & /*res*/, bool & /*success*/, Error & /*error*/) {
+  return true;
+}
+
 inline void ClientImpl::shutdown_ssl(Socket & /*socket*/,
                                      bool /*shutdown_gracefully*/) {
   // If there are any requests in flight from threads other than us, then it's
@@ -12261,27 +12276,14 @@ inline bool ClientImpl::send_(Request &req, Response &res, Error &error) {
         return false;
       }
 
-#ifdef CPPHTTPLIB_SSL_ENABLED
-      // TODO: refactoring
-      if (is_ssl()) {
-        auto &scli = static_cast<SSLClient &>(*this);
-        if (!proxy_host_.empty() && proxy_port_ != -1) {
-          auto success = false;
-          if (!scli.connect_with_proxy(socket_, req.start_time_, res, success,
-                                       error)) {
-            if (!success) { output_error_log(error, &req); }
-            return success;
-          }
-        }
-
-        if (!proxy_host_.empty() && proxy_port_ != -1) {
-          if (!scli.initialize_ssl(socket_, error)) {
-            output_error_log(error, &req);
-            return false;
-          }
+      {
+        auto success = true;
+        if (!setup_proxy_connection(socket_, req.start_time_, res, success,
+                                    error)) {
+          if (!success) { output_error_log(error, &req); }
+          return success;
         }
       }
-#endif
     }
 
     // Mark the current socket as being in use so that it cannot be closed by
@@ -12413,7 +12415,6 @@ ClientImpl::open_stream(const std::string &method, const std::string &path,
   handle.response = detail::make_unique<Response>();
   handle.error = Error::Success;
 
-  auto start_time = std::chrono::steady_clock::now();
   auto query_path = params.empty() ? path : append_query_params(path, params);
   handle.connection_ = detail::make_unique<ClientConnection>();
 
@@ -12443,24 +12444,15 @@ ClientImpl::open_stream(const std::string &method, const std::string &path,
         return handle;
       }
 
-#ifdef CPPHTTPLIB_SSL_ENABLED
-      if (is_ssl()) {
-        auto &scli = static_cast<SSLClient &>(*this);
-        if (!proxy_host_.empty() && proxy_port_ != -1) {
-          auto success = false;
-          if (!scli.connect_with_proxy(socket_, start_time, *handle.response,
-                                       success, handle.error)) {
-            if (!success) { handle.response.reset(); }
-            return handle;
-          }
-
-          if (!scli.initialize_ssl(socket_, handle.error)) {
-            handle.response.reset();
-            return handle;
-          }
+      {
+        auto success = true;
+        auto start_time = std::chrono::steady_clock::now();
+        if (!setup_proxy_connection(socket_, start_time, *handle.response,
+                                    success, handle.error)) {
+          if (!success) { handle.response.reset(); }
+          return handle;
         }
       }
-#endif
     }
 
     transfer_socket_ownership_to_handle(handle);
@@ -15437,6 +15429,24 @@ inline bool SSLClient::create_and_connect_socket(Socket &socket, Error &error) {
   return ClientImpl::create_and_connect_socket(socket, error);
 }
 
+inline bool SSLClient::setup_proxy_connection(
+    Socket &socket,
+    std::chrono::time_point<std::chrono::steady_clock> start_time,
+    Response &res, bool &success, Error &error) {
+  if (proxy_host_.empty() || proxy_port_ == -1) { return true; }
+
+  if (!connect_with_proxy(socket, start_time, res, success, error)) {
+    return false;
+  }
+
+  if (!initialize_ssl(socket, error)) {
+    success = false;
+    return false;
+  }
+
+  return true;
+}
+
 // Assumes that socket_mutex_ is locked and that there are no requests in
 // flight
 inline bool SSLClient::connect_with_proxy(