Implement a migration runner

dDatabase/Database.cpp

@@ -8,6 +8,8 @@ using namespace std;
 
 sql::Driver * Database::driver;
 sql::Connection * Database::con;
+sql::Properties Database::props;
+std::string Database::database;
 
 void Database::Connect(const string& host, const string& database, const string& username, const string& password) {
 
@@ -25,14 +27,26 @@ void Database::Connect(const string& host, const string& database, const string&
 	properties["user"] = szUsername;
 	properties["password"] = szPassword;
 	properties["autoReconnect"] = "true";
-	con = driver->connect(properties);
-	con->setSchema(szDatabase);
-} //Connect
 
-void Database::Destroy(std::string source) {
+	Database::props = properties;
+	Database::database = database;
+
+	Database::Connect();
+}
+
+void Database::Connect() {
+	con = driver->connect(Database::props);
+	con->setSchema(Database::database);
+}
+
+void Database::Destroy(std::string source, bool log) {
 	if (!con) return;
-	if (source != "") Game::logger->Log("Database", "Destroying MySQL connection from %s!\n", source.c_str());
-	else Game::logger->Log("Database", "Destroying MySQL connection!\n");
+	
+	if (log) {
+		if (source != "") Game::logger->Log("Database", "Destroying MySQL connection from %s!\n", source.c_str());
+		else Game::logger->Log("Database", "Destroying MySQL connection!\n");
+	}
+
 	con->close();
 	delete con;
 } //Destroy
@@ -48,13 +62,7 @@ sql::PreparedStatement* Database::CreatePreppedStmt(const std::string& query) {
 	sql::SQLString str(test, size);
 
 	if (!con) {
-		//Connect to the MySQL Database
-		std::string mysql_host = Game::config->GetValue("mysql_host");
-		std::string mysql_database = Game::config->GetValue("mysql_database");
-		std::string mysql_username = Game::config->GetValue("mysql_username");
-		std::string mysql_password = Game::config->GetValue("mysql_password");
-
-		Connect(mysql_host, mysql_database, mysql_username, mysql_password);
+		Connect();
 		Game::logger->Log("Database", "Trying to reconnect to MySQL\n");
 	}
 
@@ -64,13 +72,7 @@ sql::PreparedStatement* Database::CreatePreppedStmt(const std::string& query) {
 
 		con = nullptr;
 
-		//Connect to the MySQL Database
-		std::string mysql_host = Game::config->GetValue("mysql_host");
-		std::string mysql_database = Game::config->GetValue("mysql_database");
-		std::string mysql_username = Game::config->GetValue("mysql_username");
-		std::string mysql_password = Game::config->GetValue("mysql_password");
-
-		Connect(mysql_host, mysql_database, mysql_username, mysql_password);
+		Connect();
 		Game::logger->Log("Database", "Trying to reconnect to MySQL from invalid or closed connection\n");
 	}
 	
@@ -79,3 +81,6 @@ sql::PreparedStatement* Database::CreatePreppedStmt(const std::string& query) {
 	return stmt;
 } //CreatePreppedStmt
 
+void Database::Commit() {
+	Database::con->commit();
+}

dDatabase/Database.h

@@ -13,10 +13,17 @@ class Database {
 private:
 	static sql::Driver *driver;
 	static sql::Connection *con;
-
+	static sql::Properties props;
+	static std::string database;
 public:
 	static void Connect(const std::string& host, const std::string& database, const std::string& username, const std::string& password);
-	static void Destroy(std::string source="");
+	static void Connect();
+	static void Destroy(std::string source = "", bool log = true);
+
 	static sql::Statement* CreateStmt();
 	static sql::PreparedStatement* CreatePreppedStmt(const std::string& query);
+	static void Commit();
+
+	static std::string GetDatabase() { return database; }
+	static sql::Properties GetProperties() { return props; }
 };

dDatabase/MigrationRunner.cpp

@@ -0,0 +1,78 @@
+#include "MigrationRunner.h"
+
+#include "GeneralUtils.h"
+
+#include <fstream>
+#include <algorithm>
+#include <thread>
+
+void MigrationRunner::RunMigrations() {
+	auto stmt = Database::CreatePreppedStmt("CREATE TABLE IF NOT EXISTS migration_history (name TEXT NOT NULL, date TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP());");
+	stmt->executeQuery();
+    delete stmt;
+
+    sql::SQLString finalSQL = "";
+    Migration checkMigration{};
+
+    for (const auto& entry : GeneralUtils::GetFileNamesFromFolder("./migrations/")) {
+        auto migration = LoadMigration(entry);
+
+        if (migration.data.empty()) {
+            continue;
+        }
+
+        checkMigration = migration;
+
+        stmt = Database::CreatePreppedStmt("SELECT name FROM migration_history WHERE name = ?;");
+        stmt->setString(1, migration.name);
+        auto res = stmt->executeQuery();
+        bool doExit = res->next();
+        delete res;
+        delete stmt;
+        if (doExit) continue;
+
+        Game::logger->Log("MigrationRunner", "Running migration: " + migration.name + "\n");
+
+        finalSQL.append(migration.data);
+        finalSQL.append('\n');
+
+        stmt = Database::CreatePreppedStmt("INSERT INTO migration_history (name) VALUES (?);");
+        stmt->setString(1, entry);
+        stmt->execute();
+        delete stmt;
+    }
+
+    if (!finalSQL.empty()) {
+        try {
+            auto simpleStatement = Database::CreateStmt();
+            simpleStatement->execute(finalSQL);
+            delete simpleStatement;
+        }
+        catch (sql::SQLException e) {
+            Game::logger->Log("MigrationRunner", std::string("Encountered error running migration: ") + e.what() + "\n");
+        }
+    }
+}
+
+Migration MigrationRunner::LoadMigration(std::string path) {
+    Migration migration{};
+    std::ifstream file("./migrations/" + path);
+
+    if (file.is_open()) {
+        std::hash<std::string> hash;
+        
+        std::string line;
+        std::string total = "";
+
+        while (std::getline(file, line)) {
+            total += line;
+        }
+
+        file.close();
+
+        migration.name = path;
+        migration.data = total;
+    }
+    
+    return migration;
+}

dDatabase/MigrationRunner.h

@@ -0,0 +1,19 @@
+#pragma once
+
+#include "Database.h"
+
+#include "dCommonVars.h"
+#include "Game.h"
+#include "dCommonVars.h"
+#include "dLogger.h"
+
+struct Migration {
+	std::string data;
+	std::string name;
+};
+
+class MigrationRunner {
+public:
+	static void RunMigrations();
+	static Migration LoadMigration(std::string path);
+};