feat: 新增项目公共工具包，包含日志、错误、数据库、缓存、公共proto

backend/shared/postgres/postgres.go

@@ -0,0 +1,32 @@
+package postgres
+
+import (
+	"fmt"
+	"shared/logger"
+
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+)
+
+type Config struct {
+	Host     string
+	Port     string
+	User     string
+	Password string
+	DBName   string
+	SSLMode  string
+}
+
+func NewPostgresDB(cfg Config) (*gorm.DB, error) {
+	dsn := fmt.Sprintf("host=%s port=%s user=%s password=%s dbname=%s sslmode=%s",
+		cfg.Host, cfg.Port, cfg.User, cfg.Password, cfg.DBName, cfg.SSLMode)
+
+	db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{})
+	if err != nil {
+		logger.Error().Err(err).Msg("Failed to connect to PostgreSQL database")
+		return nil, err
+	}
+
+	logger.Info().Msg("Connected to PostgreSQL database successfully")
+	return db, nil
+}