feat: 完善平台总后台模块

backend/api/internal/models/dev_device_binding.go

@@ -0,0 +1,18 @@
+package models
+
+import (
+	"git.apinb.com/bsm-sdk/core/database"
+	"time"
+)
+
+// DevDeviceBinding 对应 dev_device_binding，保存设备授权绑定。
+type DevDeviceBinding struct {
+	Entity
+	SmartCylinderValveID uint64     `gorm:"column:smart_cylinder_valve_id;not null;index" json:"smart_cylinder_valve_id"`
+	UserAccountID        uint64     `gorm:"column:user_account_id;not null;index" json:"user_account_id"`
+	EffectiveAt          time.Time  `gorm:"column:effective_at;type:timestamptz;not null" json:"effective_at"`
+	ExpiredAt            *time.Time `gorm:"column:expired_at;type:timestamptz" json:"expired_at"`
+}
+
+func init()                                       { database.AppendMigrate(&DevDeviceBinding{}) }
+func (table *DevDeviceBinding) TableName() string { return "dev_device_binding" }