feat: rebuild pet app and backend around core care flows

pets-be/internal/database/database.go

@@ -4,7 +4,7 @@ import (
 	"fmt"
 	"time"
 
-	"gorm.io/driver/mysql"
+	"gorm.io/driver/postgres"
 	"gorm.io/gorm"
 	"gorm.io/gorm/logger"
 	"gorm.io/gorm/schema"
@@ -13,40 +13,31 @@ import (
 	"github.com/sundynix/pets-be/internal/model"
 )
 
-// New 建立 GORM 连接，所有表名统一加 sundynix_ 前缀
-func New(cfg *config.Config) (*gorm.DB, error) {
+func Open(cfg config.PostgresConfig, release bool) (*gorm.DB, error) {
 	logLevel := logger.Info
-	if cfg.Server.Mode == "release" {
+	if release {
 		logLevel = logger.Warn
 	}
-
-	db, err := gorm.Open(mysql.Open(cfg.MySQL.DSN()), &gorm.Config{
-		NamingStrategy: schema.NamingStrategy{
-			TablePrefix:   "sundynix_",
-			SingularTable: false,
-		},
-		// 关联在 Go 层管，不靠库级外键。迁移期建外键时 MySQL 会为外键列自动
-		// 补一个索引，和字段上的 `index` tag 撞成同名索引，父子表同迁时第二次
-		// 建索引报 1061 duplicate。关掉外键约束创建，索引就只由 index tag 建一次
-		DisableForeignKeyConstraintWhenMigrating: true,
-		Logger: logger.Default.LogMode(logLevel),
+	db, err := gorm.Open(postgres.Open(cfg.DSN()), &gorm.Config{
+		NamingStrategy: schema.NamingStrategy{TablePrefix: "sundynix_", SingularTable: true},
+		Logger:         logger.Default.LogMode(logLevel),
 	})
 	if err != nil {
-		return nil, fmt.Errorf("gorm open: %w", err)
+		return nil, fmt.Errorf("open postgres: %w", err)
 	}
-
 	sqlDB, err := db.DB()
 	if err != nil {
 		return nil, err
 	}
-	sqlDB.SetMaxOpenConns(50)
+	sqlDB.SetMaxOpenConns(25)
 	sqlDB.SetMaxIdleConns(10)
 	sqlDB.SetConnMaxLifetime(time.Hour)
-
 	return db, nil
 }
 
-// Migrate 自动建表
 func Migrate(db *gorm.DB) error {
-	return db.AutoMigrate(model.AllModels()...)
+	if err := db.AutoMigrate(model.All()...); err != nil {
+		return err
+	}
+	return db.Exec("CREATE UNIQUE INDEX IF NOT EXISTS idx_sundynix_walk_one_active_per_user ON sundynix_walk (user_id) WHERE status IN ('active', 'paused')").Error
 }