add database file and file locking

CMakeLists.txt

@@ -23,8 +23,10 @@ include(GNUInstallDirs)
 # dtranslatebot Source files
 set(DTRANSLATEBOT_HEADERS
     src/database_core.h
+    src/database_file.h
     src/message_queue.h
     src/settings.h
+    src/settings_types.h
     src/slashcommands.h
     src/submit_queue.h
     src/translator_core.h
@@ -33,6 +35,7 @@ set(DTRANSLATEBOT_HEADERS
 )
 set(DTRANSLATEBOT_SOURCES
     src/database_core.cpp
+    src/database_file.cpp
     src/main.cpp
     src/message_queue.cpp
     src/settings.cpp
@@ -55,7 +58,7 @@ find_package(Threads REQUIRED)
 
 # dtranslatebot Target + Installs
 add_executable(dtranslatebot ${DTRANSLATEBOT_HEADERS} ${DTRANSLATEBOT_SOURCES})
-target_link_libraries(dtranslatebot Threads::Threads ${DPP_LIBRARIES})
+target_link_libraries(dtranslatebot PRIVATE Threads::Threads ${DPP_LIBRARIES})
 target_include_directories(dtranslatebot PRIVATE ${DPP_INCLUDE_DIR})
 set_target_properties(dtranslatebot PROPERTIES
     CXX_STANDARD 17

src/database_core.h

@@ -19,8 +19,7 @@
 #ifndef DATABASE_CORE_H
 #define DATABASE_CORE_H
 
-#include <vector>
-#include "settings.h"
+#include "settings_types.h"
 
 namespace bot {
     namespace database {

src/database_file.cpp

@@ -0,0 +1,118 @@
+/*****************************************************************************
+* dtranslatebot Discord Translate Bot
+* Copyright (C) 2024 Syping
+*
+* Redistribution and use in source and binary forms, with or without modification,
+* are permitted provided that the following conditions are met:
+*
+* 1. Redistributions of source code must retain the above copyright notice,
+* this list of conditions and the following disclaimer.
+*
+* 2. Redistributions in binary form must reproduce the above copyright notice,
+* this list of conditions and the following disclaimer in the documentation
+* and/or other materials provided with the distribution.
+*
+* This software is provided as-is, no warranties are given to you, we are not
+* responsible for anything with use of the software, you are self responsible.
+*****************************************************************************/
+
+#ifdef __unix__
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#endif
+#include <iostream>
+#include "database_file.h"
+using namespace bot::database;
+
+file::file(const std::filesystem::path &storage_path) : m_storagePath(storage_path)
+{
+    std::cout << "[Launch] Checking working directory..." << std::endl;
+    if (!std::filesystem::exists(storage_path)) {
+        std::cerr << "[Error] Storage directory " << storage_path << " can not be found" << std::endl;
+        throw std::runtime_error("Storage directory can not be found");
+    }
+
+#ifdef __unix__
+    struct flock lock;
+    lock.l_start = 0;
+    lock.l_len = 0;
+    lock.l_pid = getpid();
+    lock.l_type = F_WRLCK;
+    lock.l_whence = SEEK_SET;
+
+    const std::string lock_file = storage_path / ".lock";
+    fd = open(lock_file.c_str(), O_CREAT | O_WRONLY | O_TRUNC, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
+    if (fd == -1) {
+        std::cerr << "[Error] Storage directory " << storage_path << " can not be locked" << std::endl;
+        throw std::system_error(errno, std::system_category());
+    }
+    if (fcntl(fd, F_SETLK, &lock) == -1) {
+        std::cerr << "[Error] Storage directory " << storage_path << " can not be locked" << std::endl;
+        throw std::system_error(errno, std::system_category());
+    }
+#endif
+}
+
+file::~file()
+{
+#ifdef __unix__
+    close(fd);
+#endif
+}
+
+bool file::add_channel_target(dpp::snowflake guild_id, dpp::snowflake channel_id, const bot::settings::target &target)
+{
+#ifndef NDEBUG
+    std::cerr << "[Debug] database::add_channel_target(dpp::snowflake, dpp::snowflake, const bot::settings::target&) have being called." << std::endl;
+#endif
+    return false;
+}
+
+std::variant<std::monostate,bot::settings::target> file::find_channel_target(dpp::snowflake guild_id, dpp::snowflake channel_id, const std::string &target)
+{
+#ifndef NDEBUG
+    std::cerr << "[Debug] database::find_channel_target(dpp::snowflake, dpp::snowflake, const std::string&) have being called." << std::endl;
+#endif
+    return {};
+}
+
+std::vector<dpp::snowflake> file::get_channels(dpp::snowflake guild_id)
+{
+#ifndef NDEBUG
+    std::cerr << "[Debug] database::get_channels(dpp::snowflake) have being called." << std::endl;
+#endif
+    return {};
+}
+
+std::string file::get_channel_source(dpp::snowflake guild_id, dpp::snowflake channel_id)
+{
+#ifndef NDEBUG
+    std::cerr << "[Debug] database::get_channel_source(dpp::snowflake, dpp::snowflake) have being called." << std::endl;
+#endif
+    return {};
+}
+
+std::vector<bot::settings::target> file::get_channel_targets(dpp::snowflake guild_id, dpp::snowflake channel_id)
+{
+#ifndef NDEBUG
+    std::cerr << "[Debug] database::get_channel_targets(dpp::snowflake, dpp::snowflake) have being called." << std::endl;
+#endif
+    return {};
+}
+
+std::vector<dpp::snowflake> file::get_guilds()
+{
+#ifndef NDEBUG
+    std::cerr << "[Debug] database::get_guilds() have being called." << std::endl;
+#endif
+    return {};
+}
+
+bool file::set_channel_source(dpp::snowflake guild_id, dpp::snowflake channel_id, const std::string &source)
+{
+#ifndef NDEBUG
+    std::cerr << "[Debug] database::set_channel_source(dpp::snowflake, dpp::snowflake, const std::string&) have being called." << std::endl;
+#endif
+    return false;
+}

src/database_file.h

@@ -0,0 +1,50 @@
+/*****************************************************************************
+* dtranslatebot Discord Translate Bot
+* Copyright (C) 2024 Syping
+*
+* Redistribution and use in source and binary forms, with or without modification,
+* are permitted provided that the following conditions are met:
+*
+* 1. Redistributions of source code must retain the above copyright notice,
+* this list of conditions and the following disclaimer.
+*
+* 2. Redistributions in binary form must reproduce the above copyright notice,
+* this list of conditions and the following disclaimer in the documentation
+* and/or other materials provided with the distribution.
+*
+* This software is provided as-is, no warranties are given to you, we are not
+* responsible for anything with use of the software, you are self responsible.
+*****************************************************************************/
+
+#ifndef DATABASE_FILE_H
+#define DATABASE_FILE_H
+
+#include <mutex>
+#include <filesystem>
+#include "database_core.h"
+
+namespace bot {
+    namespace database {
+        class file : public database {
+        public:
+            explicit file(const std::filesystem::path &storage_path);
+            ~file();
+            bool add_channel_target(dpp::snowflake guild_id, dpp::snowflake channel_id, const bot::settings::target &target) override;
+            std::variant<std::monostate,bot::settings::target> find_channel_target(dpp::snowflake guild_id, dpp::snowflake channel_id, const std::string &target) override;
+            std::vector<dpp::snowflake> get_channels(dpp::snowflake guild_id) override;
+            std::string get_channel_source(dpp::snowflake guild_id, dpp::snowflake channel_id) override;
+            std::vector<bot::settings::target> get_channel_targets(dpp::snowflake guild_id, dpp::snowflake channel_id) override;
+            std::vector<dpp::snowflake> get_guilds() override;
+            bool set_channel_source(dpp::snowflake guild_id, dpp::snowflake channel_id, const std::string &source) override;
+
+        private:
+#ifdef __unix__
+            int fd;
+#endif
+            std::mutex m_mutex;
+            std::filesystem::path m_storagePath;
+        };
+    }
+}
+
+#endif // DATABASE_FILE_H

src/main.cpp

@@ -42,12 +42,6 @@ int main(int argc, char* argv[]) {
         return 2;
     }
 
-    std::cout << "[Launch] Checking working directory..." << std::endl;
-    if (!std::filesystem::exists(settings.storage_path())) {
-        std::cerr << "[Error] Storage directory " << settings.storage_path() << " can not be found" << std::endl;
-        return 2;
-    }
-
     dpp::cluster bot(settings.token(), dpp::i_default_intents | dpp::i_message_content);
     bot.on_log([&bot](const dpp::log_t &event) {
         std::cerr << "[Log] " << event.message << std::endl;

src/settings.cpp

@@ -17,10 +17,9 @@
 *****************************************************************************/
 
 #include <dpp/json.h>
-#include <mutex>
-#include <filesystem>
 #include <fstream>
 #include <iostream>
+#include "database_file.h"
 #include "settings.h"
 #include "translator_libretranslate.h"
 using namespace bot::settings;
@@ -260,18 +259,15 @@ const std::vector<std::string> settings::preferred_languages() const
     return m_prefLangs;
 }
 
-const std::filesystem::path settings::storage_path() const
+std::shared_ptr<bot::database::database> settings::get_database() const
 {
-    const std::lock_guard<std::recursive_mutex> guard(m_mutex);
-    return m_storagePath;
+    return m_database;
 }
 
 std::unique_ptr<bot::translator::translator> settings::get_translator() const
 {
     const std::lock_guard<std::recursive_mutex> guard(m_mutex);
-    std::unique_ptr<bot::translator::libretranslate> libretranslate(
-                new bot::translator::libretranslate(m_translator.hostname, m_translator.port, m_translator.url, m_translator.tls, m_translator.apiKey));
-    return libretranslate;
+    return std::make_unique<bot::translator::libretranslate>(m_translator.hostname, m_translator.port, m_translator.url, m_translator.tls, m_translator.apiKey);
 }
 
 const std::string settings::token() const
@@ -318,14 +314,18 @@ bool settings::parse(const std::string &data)
         const std::lock_guard<std::recursive_mutex> guard(m_mutex);
         m_token = *json_token;
 
+        // Support more Database systems in the future
+        std::filesystem::path storage_path;
         auto json_storage = json.find("storage");
         if (json_storage != json.end())
-            m_storagePath = std::string(*json_storage);
+            storage_path = std::string(*json_storage);
         else if (char *storagepath = getenv("DTRANSLATEBOT_STORAGE"))
-            m_storagePath = storagepath;
+            storage_path  = storagepath;
 
-        if (m_storagePath.empty())
-            m_storagePath = std::filesystem::current_path();
+        if (storage_path.empty())
+            storage_path = std::filesystem::current_path();
+
+        m_database = std::make_shared<bot::database::file>(storage_path);
 
         auto json_translator = json.find("translator");
         if (json_translator == json.end()) {

src/settings.h

@@ -18,38 +18,13 @@
 
 #ifndef SETTINGS_H
 #define SETTINGS_H
-#include <cstdint>
-#include <dpp/snowflake.h>
-#include <dpp/webhook.h>
-#include <filesystem>
 #include <mutex>
-#include <string>
-#include <vector>
+#include "database_core.h"
+#include "settings_types.h"
 #include "translator_core.h"
 
 namespace bot {
     namespace settings {
-        struct target {
-            std::string target;
-            dpp::webhook webhook;
-        };
-        struct channel {
-            dpp::snowflake id;
-            std::string source;
-            std::vector<bot::settings::target> targets;
-        };
-        struct guild {
-            dpp::snowflake id;
-            std::vector<bot::settings::channel> channel;
-        };
-        struct translator {
-            std::string hostname;
-            uint16_t port;
-            std::string url;
-            bool tls;
-            std::string apiKey;
-        };
-
         class settings {
         public:
             /* add functions */
@@ -63,7 +38,7 @@ namespace bot {
             const channel* get_channel(dpp::snowflake guild_id, dpp::snowflake channel_id) const;
             const guild* get_guild(dpp::snowflake guild_id) const;
             const std::vector<std::string> preferred_languages() const;
-            const std::filesystem::path storage_path() const;
+            std::shared_ptr<bot::database::database> get_database() const;
             std::unique_ptr<bot::translator::translator> get_translator() const;
             const std::string token() const;
 
@@ -82,9 +57,9 @@ namespace bot {
             mutable std::recursive_mutex m_mutex;
             size_t m_externallyLockedCount;
             uint16_t m_avatarSize;
+            std::shared_ptr<bot::database::database> m_database;
             std::vector<guild> m_guilds;
             std::vector<std::string> m_prefLangs;
-            std::filesystem::path m_storagePath;
             bot::settings::translator m_translator;
             std::string m_token;
             std::vector<dpp::snowflake> m_webhookIds;

src/settings_types.h

@@ -0,0 +1,53 @@
+/*****************************************************************************
+* dtranslatebot Discord Translate Bot
+* Copyright (C) 2023-2024 Syping
+*
+* Redistribution and use in source and binary forms, with or without modification,
+* are permitted provided that the following conditions are met:
+*
+* 1. Redistributions of source code must retain the above copyright notice,
+* this list of conditions and the following disclaimer.
+*
+* 2. Redistributions in binary form must reproduce the above copyright notice,
+* this list of conditions and the following disclaimer in the documentation
+* and/or other materials provided with the distribution.
+*
+* This software is provided as-is, no warranties are given to you, we are not
+* responsible for anything with use of the software, you are self responsible.
+*****************************************************************************/
+
+#ifndef SETTINGS_TYPES_H
+#define SETTINGS_TYPES_H
+
+#include <cstdint>
+#include <dpp/snowflake.h>
+#include <dpp/webhook.h>
+#include <string>
+#include <vector>
+
+namespace bot {
+    namespace settings {
+        struct target {
+            std::string target;
+            dpp::webhook webhook;
+        };
+        struct channel {
+            dpp::snowflake id;
+            std::string source;
+            std::vector<bot::settings::target> targets;
+        };
+        struct guild {
+            dpp::snowflake id;
+            std::vector<bot::settings::channel> channel;
+        };
+        struct translator {
+            std::string hostname;
+            uint16_t port;
+            std::string url;
+            bool tls;
+            std::string apiKey;
+        };
+    }
+}
+
+#endif // SETTINGS_TYPES_H