db: simplify API (exec/query/transaction), add env-based config and full HTTP showcase

Author: GaspardKirira

examples/.env.example

@@ -0,0 +1,37 @@
+# =========================================================
+# Vix HTTP + DB showcase
+# Copy this file to ".env"
+# =========================================================
+
+# Database engine:
+#   - sqlite
+#   - mysql
+DATABASE_ENGINE=sqlite
+
+# SQLite configuration
+DATABASE_SQLITE_PATH=vix.db
+
+# MySQL configuration
+# Used only if DATABASE_ENGINE=mysql
+DATABASE_DEFAULT_HOST=127.0.0.1
+DATABASE_DEFAULT_PORT=3306
+DATABASE_DEFAULT_USER=root
+DATABASE_DEFAULT_PASSWORD=
+DATABASE_DEFAULT_NAME=vix
+
+# Server configuration
+SERVER_PORT=8080
+SERVER_REQUEST_TIMEOUT=2000
+SERVER_IO_THREADS=0
+SERVER_SESSION_TIMEOUT_SEC=20
+SERVER_BENCH_MODE=false
+
+# Logging configuration
+LOGGING_ASYNC=true
+LOGGING_QUEUE_MAX=20000
+LOGGING_DROP_ON_OVERFLOW=true
+
+# WAF configuration
+WAF_MODE=basic
+WAF_MAX_TARGET_LEN=4096
+WAF_MAX_BODY_BYTES=1048576

examples/basic_connect.cpp

@@ -7,12 +7,7 @@ int main()
   {
     auto db = vix::db::Database::sqlite("vix.db");
 
-    auto conn = db.pool().acquire();
-    if (!conn->ping())
-    {
-      std::cerr << "DB ping failed\n";
-      return 1;
-    }
+    db.exec("CREATE TABLE IF NOT EXISTS healthcheck (id INTEGER PRIMARY KEY)");
 
     std::cout << "DB connected successfully\n";
     return 0;

examples/config/.env.example

@@ -0,0 +1,10 @@
+DATABASE_ENGINE=sqlite
+DATABASE_SQLITE_PATH=vix.db
+
+# MySQL alternative
+# DATABASE_ENGINE=mysql
+# DATABASE_DEFAULT_HOST=127.0.0.1
+# DATABASE_DEFAULT_PORT=3306
+# DATABASE_DEFAULT_USER=root
+# DATABASE_DEFAULT_PASSWORD=
+# DATABASE_DEFAULT_NAME=vixdb

examples/config/database_from_env.cpp

@@ -0,0 +1,50 @@
+#include <iostream>
+#include <vix/config/Config.hpp>
+#include <vix/db/Database.hpp>
+
+int main()
+{
+  try
+  {
+    auto &cfg = vix::config::Config::getInstance(".env");
+
+    std::cout << "database.engine = "
+              << cfg.getString("database.engine", "sqlite") << "\n";
+
+    std::cout << "database.default.host = "
+              << cfg.getString("database.default.host", "127.0.0.1") << "\n";
+
+    std::cout << "database.default.port = "
+              << cfg.getInt("database.default.port", 3306) << "\n";
+
+    std::cout << "database.default.user = "
+              << cfg.getString("database.default.user", "root") << "\n";
+
+    std::cout << "database.default.name = "
+              << cfg.getString("database.default.name", "") << "\n";
+
+    auto db = vix::db::Database::from_env(".env");
+
+    db.exec(
+        "CREATE TABLE IF NOT EXISTS users ("
+        "id INTEGER PRIMARY KEY AUTOINCREMENT, "
+        "name TEXT NOT NULL)");
+
+    db.exec("INSERT INTO users (name) VALUES (?)", "Gaspard");
+
+    auto rows = db.query("SELECT id, name FROM users");
+
+    while (rows->next())
+    {
+      const auto &row = rows->row();
+      std::cout << row.getInt64(0) << " - " << row.getString(1) << "\n";
+    }
+
+    return 0;
+  }
+  catch (const std::exception &e)
+  {
+    std::cerr << "Config/DB error: " << e.what() << "\n";
+    return 1;
+  }
+}