licensed, a bit better file handling, a bit better migration handling

database/mysql/mysql.cpp

@@ -1,6 +1,10 @@
+//  SPDX-FileCopyrightText: 2023 Yury Gubich <blue@macaw.me>
+//  SPDX-License-Identifier: GPL-3.0-or-later
+
 #include "mysql.h"
 
 #include <fstream>
+#include <iostream>
 
 #include "mysqld_error.h"
 
@@ -8,6 +12,8 @@
 
 constexpr const char* updateQuery = "UPDATE system SET `value` = ? WHERE `key` = 'version'";
 
+static const std::filesystem::path buildSQLPath = "database";
+
 struct ResDeleter {
     void operator () (MYSQL_RES* res) {
         mysql_free_result(res);
@@ -98,8 +104,15 @@ void MySQL::disconnect() {
     mysql_init(con);            //this is ridiculous!
 }
 
-void MySQL::executeFile(const std::string& path) {
+void MySQL::executeFile(const std::filesystem::path& relativePath) {
     MYSQL* con = &connection;
+    std::filesystem::path path = sharedPath() / relativePath;
+    if (!std::filesystem::exists(path))
+        throw std::runtime_error("Error executing file "
+            + std::filesystem::absolute(path).string()
+            + ": file doesn't exist");
+
+    std::cout << "Executing file " << path << std::endl;
     std::ifstream inputFile(path);
     std::string query;
     while (std::getline(inputFile, query, ';')) {
@@ -109,7 +122,7 @@ void MySQL::executeFile(const std::string& path) {
             if (errcode == ER_EMPTY_QUERY)
                 continue;
 
-            throw std::runtime_error("Error executing file " + path + ": " + mysql_error(con));
+            throw std::runtime_error("Error executing file " + path.string() + ": " + mysql_error(con));
         }
 
     }
@@ -144,3 +157,20 @@ void MySQL::setVersion(uint8_t version) {
     statement.bind(strVersion.data(), MYSQL_TYPE_VAR_STRING);
     statement.execute();
 }
+
+void MySQL::migrate(uint8_t targetVersion) {
+    uint8_t currentVersion = getVersion();
+
+    while (currentVersion < targetVersion) {
+        std::string fileName = "migrations/m" + std::to_string(currentVersion) + ".sql";
+        std::cout << "Performing migration "
+            << std::to_string(currentVersion)
+            << " -> "
+            << std::to_string(++currentVersion)
+        << std::endl;
+        executeFile(fileName);
+        setVersion(currentVersion);
+    }
+
+    std::cout << "Database is now on actual version " << std::to_string(targetVersion) << std::endl;
+}

database/mysql/mysql.h

@@ -1,10 +1,15 @@
+//  SPDX-FileCopyrightText: 2023 Yury Gubich <blue@macaw.me>
+//  SPDX-License-Identifier: GPL-3.0-or-later
+
 #pragma once
 
 #include <stdexcept>
+#include <filesystem>
 
 #include <mysql.h>
 
 #include "database/dbinterface.h"
+#include "utils/helpers.h"
 
 class MySQL : public DBInterface {
     class Statement;
@@ -17,10 +22,13 @@ public:
     void setCredentials(const std::string& login, const std::string& password) override;
     void setDatabase(const std::string& database) override;
 
-    void executeFile(const std::string& path) override;
+    void migrate(uint8_t targetVersion) override;
     uint8_t getVersion() override;
     void setVersion(uint8_t version) override;
 
+private:
+    void executeFile(const std::filesystem::path& relativePath);
+
 protected:
     MYSQL connection;
     std::string login;

database/mysql/statement.cpp

@@ -1,3 +1,6 @@
+//  SPDX-FileCopyrightText: 2023 Yury Gubich <blue@macaw.me>
+//  SPDX-License-Identifier: GPL-3.0-or-later
+
 #include "statement.h"
 
 #include <cstring>

database/mysql/statement.h

@@ -1,3 +1,6 @@
+//  SPDX-FileCopyrightText: 2023 Yury Gubich <blue@macaw.me>
+//  SPDX-License-Identifier: GPL-3.0-or-later
+
 #pragma once
 
 #include <vector>