API Subsonic: first working version, still WIP (missing commands, no authentication)

src/api/subsonic/SubsonicResponse.hpp

@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2019 Emeric Poupon
+ *
+ * This file is part of LMS.
+ *
+ * LMS is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * LMS is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with LMS.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <map>
+#include <string>
+#include <vector>
+
+namespace API::Subsonic
+{
+
+enum class ResponseFormat
+{
+	xml,
+	json,
+};
+
+std::string ResponseFormatToMimeType(ResponseFormat format);
+
+class Error
+{
+	public:
+		enum class Code
+		{
+			Generic = 0,
+			RequiredParameterMissing = 10,
+			ClientMustUpgrade = 20,
+			ServerMustUpgrade = 30,
+			WrongUsernameOrPassword = 40,
+			UserNotAuthorized = 50,
+			RequestedDataNotFound = 70,
+		};
+
+		Error(Code code);
+		Error(const std::string& message);
+
+		Code getCode() const { return _code; }
+		const std::string& getMessage() const { return _message; }
+
+	private:
+		Code _code;
+		std::string _message;
+};
+
+class Response
+{
+	public:
+		struct Node
+		{
+			std::map<std::string, std::string> attributes;
+			std::map<std::string, std::vector<Node>> children;
+			std::map<std::string, std::vector<Node>> childrenArrays;
+
+			// Helpers
+			void setAttribute(const std::string& key, const std::string& value);
+
+			Node& createChild(const std::string& key);
+			Node& createArrayChild(const std::string& key);
+
+			void addChild(const std::string& key, Node node);
+			void addArrayChild(const std::string& key, Node node);
+		};
+
+		static Response createOkResponse();
+		static Response createFailedResponse(const Error& error);
+
+		virtual ~Response() {}
+		Response(const Response&) = delete;
+		Response& operator=(const Response&) = delete;
+		Response(Response&&) = default;
+		Response& operator=(Response&&) = default;
+
+		Node& createNode(const std::string& key);
+
+	private:
+		friend void responseToStream(const Response& response, ResponseFormat format, std::ostream& os);
+
+		Response() = default;
+		Node _root;
+};
+
+} // namespace
+