feat(db): add Database facade and simplify examples

Author: GaspardKirira

examples/CMakeLists.txt

@@ -14,4 +14,10 @@ if (VIX_DB_BUILD_EXAMPLES)
   vix_db_example(prepared_query)
   vix_db_example(transaction)
   vix_db_example(migrations)
+  vix_db_example(sqlite_basic)
+  vix_db_example(pool_usage)
+
+  if (VIX_DB_HAS_MYSQL)
+    vix_db_example(mysql_basic)
+  endif()
 endif()

examples/basic_connect.cpp

@@ -1,26 +1,25 @@
-#include <vix/db/db.hpp>
 #include <iostream>
-
-using namespace vix::db;
+#include <vix/db/db.hpp>
 
 int main()
 {
-  DbConfig cfg;
-  cfg.engine = Engine::MySQL;
-  cfg.mysql.host = "tcp://127.0.0.1:3306";
-  cfg.mysql.user = "root";
-  cfg.mysql.password = "";
-  cfg.mysql.database = "vixdb";
+  try
+  {
+    auto db = vix::db::Database::sqlite("vix.db");
 
-  Database db(cfg);
+    auto conn = db.pool().acquire();
+    if (!conn->ping())
+    {
+      std::cerr << "DB ping failed\n";
+      return 1;
+    }
 
-  auto conn = db.pool().acquire();
-  if (!conn->ping())
+    std::cout << "DB connected successfully\n";
+    return 0;
+  }
+  catch (const std::exception &e)
   {
-    std::cerr << "DB ping failed\n";
+    std::cerr << "DB error: " << e.what() << "\n";
     return 1;
   }
-
-  std::cout << "DB connected successfully\n";
-  return 0;
 }

examples/migrations.cpp

@@ -1,76 +1,60 @@
-#include <vix/db/db.hpp>
-
-#include <iostream>
 #include <filesystem>
+#include <iostream>
 #include <string>
 
-using namespace vix::db;
-
-static DbConfig make_mysql_cfg()
-{
-  DbConfig cfg;
-  cfg.engine = Engine::MySQL;
-  cfg.mysql.host = "tcp://127.0.0.1:3306";
-  cfg.mysql.user = "root";
-  cfg.mysql.password = "";
-  cfg.mysql.database = "vixdb";
-  cfg.mysql.pool.min = 1;
-  cfg.mysql.pool.max = 4;
-  return cfg;
-}
+#include <vix/db/db.hpp>
 
-// ------------------------------
-// 1) Code-based migration example
-// ------------------------------
-class CreateUsersTable final : public Migration
+class CreateUsersTable final : public vix::db::Migration
 {
 public:
-  std::string id() const override { return "2026-01-22-create-users"; }
+  std::string id() const override
+  {
+    return "2026-01-22-create-users";
+  }
 
-  void up(Connection &c) override
+  void up(vix::db::Connection &c) override
   {
     auto st = c.prepare(
         "CREATE TABLE IF NOT EXISTS users ("
-        "  id BIGINT PRIMARY KEY AUTO_INCREMENT,"
-        "  name VARCHAR(255) NOT NULL,"
-        "  age INT NOT NULL"
+        "id INTEGER PRIMARY KEY AUTOINCREMENT, "
+        "name TEXT NOT NULL, "
+        "age INTEGER NOT NULL"
         ");");
     st->exec();
   }
 
-  void down(Connection &c) override
+  void down(vix::db::Connection &c) override
   {
     auto st = c.prepare("DROP TABLE IF EXISTS users;");
     st->exec();
   }
 };
 
-static void run_code_migrations(Database &db)
+static void runCodeMigrations(vix::db::Database &db)
 {
   std::cout << "[migrations] running code migrations...\n";
 
-  Transaction tx(db.pool());
+  vix::db::Transaction tx(db.pool());
 
-  CreateUsersTable m1;
-  MigrationsRunner runner(tx.conn());
-  runner.add(&m1);
+  CreateUsersTable migration;
+  vix::db::MigrationsRunner runner(tx.conn());
+  runner.add(&migration);
   runner.runAll();
 
   tx.commit();
   std::cout << "[migrations] done (code)\n";
 }
 
-// ------------------------------
-// 2) File-based migration example
-// ------------------------------
-static void run_file_migrations(Database &db, std::filesystem::path dir)
+static void runFileMigrations(vix::db::Database &db,
+                              std::filesystem::path dir)
 {
-  std::cout << "[migrations] running file migrations from: " << dir.string() << "\n";
+  std::cout << "[migrations] running file migrations from: "
+            << dir.string() << "\n";
 
-  Transaction tx(db.pool());
+  vix::db::Transaction tx(db.pool());
 
-  FileMigrationsRunner runner(tx.conn(), std::move(dir));
-  runner.setTable("schema_migrations"); // optional (default already)
+  vix::db::FileMigrationsRunner runner(tx.conn(), std::move(dir));
+  runner.setTable("schema_migrations");
   runner.applyAll();
 
   tx.commit();
@@ -81,13 +65,10 @@ int main()
 {
   try
   {
-    Database db(make_mysql_cfg());
-
-    // 1) Code migrations
-    run_code_migrations(db);
+    auto db = vix::db::Database::sqlite("vix.db");
 
-    // 2) File migrations (expects ./migrations/*.up.sql and *.down.sql)
-    run_file_migrations(db, std::filesystem::path{"migrations"});
+    runCodeMigrations(db);
+    runFileMigrations(db, std::filesystem::path{"migrations"});
 
     std::cout << "OK\n";
     return 0;

examples/mysql_basic.cpp

@@ -0,0 +1,39 @@
+#include <iostream>
+#include <vix/db/Database.hpp>
+
+int main()
+{
+  try
+  {
+    auto db = vix::db::Database::mysql(
+        "tcp://127.0.0.1:3306",
+        "root",
+        "",
+        "vixdb");
+
+    auto &pool = db.pool();
+
+    {
+      vix::db::PooledConn conn(pool);
+
+      conn->prepare(
+              "CREATE TABLE IF NOT EXISTS users ("
+              "id BIGINT AUTO_INCREMENT PRIMARY KEY, "
+              "name TEXT)")
+          ->exec();
+
+      conn->prepare(
+              "INSERT INTO users (name) VALUES (?)")
+          ->bind(1, std::string("Gaspard"));
+
+      std::cout << "[OK] inserted user\n";
+    }
+
+    return 0;
+  }
+  catch (const std::exception &e)
+  {
+    std::cerr << "[ERR] " << e.what() << "\n";
+    return 1;
+  }
+}

examples/pool_usage.cpp

@@ -0,0 +1,56 @@
+#include <iostream>
+#include <thread>
+#include <vector>
+
+#include <vix/db/Database.hpp>
+
+void worker(vix::db::ConnectionPool &pool, int id)
+{
+  vix::db::PooledConn conn(pool);
+
+  conn->prepare(
+          "INSERT INTO users (name) VALUES (?)")
+      ->bind(1, std::string("worker_" + std::to_string(id)));
+
+  std::cout << "[thread] inserted " << id << "\n";
+}
+
+int main()
+{
+  try
+  {
+    auto db = vix::db::Database::sqlite("vix.db");
+
+    auto &pool = db.pool();
+
+    {
+      vix::db::PooledConn conn(pool);
+      conn->prepare(
+              "CREATE TABLE IF NOT EXISTS users ("
+              "id INTEGER PRIMARY KEY AUTOINCREMENT, "
+              "name TEXT)")
+          ->exec();
+    }
+
+    std::vector<std::thread> threads;
+
+    for (int i = 0; i < 4; ++i)
+    {
+      threads.emplace_back(worker, std::ref(pool), i);
+    }
+
+    for (auto &t : threads)
+    {
+      t.join();
+    }
+
+    std::cout << "[OK] done\n";
+
+    return 0;
+  }
+  catch (const std::exception &e)
+  {
+    std::cerr << "[ERR] " << e.what() << "\n";
+    return 1;
+  }
+}

examples/prepared_query.cpp

@@ -1,32 +1,50 @@
-#include <vix/db/db.hpp>
+#include <cstdint>
 #include <iostream>
-
-using namespace vix::db;
+#include <vix/db/db.hpp>
 
 int main()
 {
-  DbConfig cfg;
-  cfg.engine = Engine::MySQL;
-  cfg.mysql.host = "tcp://127.0.0.1:3306";
-  cfg.mysql.user = "root";
-  cfg.mysql.password = "";
-  cfg.mysql.database = "vixdb";
-  cfg.mysql.pool.min = 1;
-  cfg.mysql.pool.max = 8;
-
-  Database db(cfg);
-
-  auto conn = db.pool().acquire();
-  auto st = conn->prepare("SELECT id, name FROM users WHERE age > ?");
-
-  st->bind(1, 18);
-  // or: st->bind(1, std::int64_t{18});
-  // or: st->bind(1, i64(18));
-
-  auto rs = st->query();
-  while (rs->next())
+  try
+  {
+    auto db = vix::db::Database::sqlite("vix.db");
+
+    {
+      auto conn = db.pool().acquire();
+
+      conn->prepare(
+              "CREATE TABLE IF NOT EXISTS users ("
+              "id INTEGER PRIMARY KEY AUTOINCREMENT, "
+              "name TEXT NOT NULL, "
+              "age INTEGER NOT NULL)")
+          ->exec();
+
+      auto insert = conn->prepare(
+          "INSERT INTO users (name, age) VALUES (?, ?)");
+
+      insert->bind(1, std::string("Alice"));
+      insert->bind(2, static_cast<std::int64_t>(20));
+      insert->exec();
+    }
+
+    {
+      auto conn = db.pool().acquire();
+      auto st = conn->prepare("SELECT id, name FROM users WHERE age > ?");
+
+      st->bind(1, static_cast<std::int64_t>(18));
+
+      auto rs = st->query();
+      while (rs->next())
+      {
+        const auto &row = rs->row();
+        std::cout << row.getInt64(0) << " " << row.getString(1) << "\n";
+      }
+    }
+
+    return 0;
+  }
+  catch (const std::exception &e)
   {
-    const auto &row = rs->row();
-    std::cout << row.getInt64(0) << " " << row.getString(1) << "\n";
+    std::cerr << "DB error: " << e.what() << "\n";
+    return 1;
   }
 }

examples/sqlite_basic.cpp

@@ -0,0 +1,55 @@
+#include <iostream>
+#include <vix/db/Database.hpp>
+
+int main()
+{
+  try
+  {
+    // Ultra simple
+    auto db = vix::db::Database::sqlite("vix.db");
+
+    auto &pool = db.pool();
+
+    {
+      vix::db::PooledConn conn(pool);
+
+      conn->prepare(
+              "CREATE TABLE IF NOT EXISTS users ("
+              "id INTEGER PRIMARY KEY AUTOINCREMENT, "
+              "name TEXT)")
+          ->exec();
+
+      conn->prepare(
+              "INSERT INTO users (name) VALUES (?)")
+          ->bind(1, std::string("Gaspard"));
+
+      conn->prepare(
+              "INSERT INTO users (name) VALUES (?)")
+          ->bind(1, std::string("Adastra"));
+
+      std::cout << "[OK] inserted users\n";
+    }
+
+    {
+      vix::db::PooledConn conn(pool);
+
+      auto stmt = conn->prepare("SELECT id, name FROM users");
+      auto rs = stmt->query();
+
+      while (rs->next())
+      {
+        const auto &row = rs->row();
+        std::cout << "User: "
+                  << row.getInt64(0) << " "
+                  << row.getString(1) << "\n";
+      }
+    }
+
+    return 0;
+  }
+  catch (const std::exception &e)
+  {
+    std::cerr << "[ERR] " << e.what() << "\n";
+    return 1;
+  }
+}