feat: 实现数据库连接和健康检查端点

internal/database/database.go

@@ -1,10 +1,31 @@
 package database
 
-import "gorm.io/gorm"
+import (
+	"fmt"
 
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+)
+
+// DatabaseConfig
 type DatabaseConfig struct {
+	Host     string
+	Port     int
+	Username string
+	Password string
+	DBName   string
+	SSLMode  string
 }
 
 func Connect(cfg DatabaseConfig) (*gorm.DB, error) {
-	return nil, nil
+	dsn := fmt.Sprintf("host=%s port=%d user=%s password=%s dbname=%s sslmode=%s",
+		cfg.Host, cfg.Port, cfg.Username, cfg.Password, cfg.DBName, cfg.SSLMode,
+	)
+
+	db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{})
+	if err != nil {
+		return nil, fmt.Errorf("connect database: %w", err)
+	}
+
+	return db, nil
 }