Restore foreign keys and add constraints (#1562)

* fix #1482, restore foregin keys, add constraints

* #1562, fix tests, fix formatting

* #1562: fix tests

* #1562: fix local run of test_integration

hscontrol/types/node.go

@@ -108,20 +108,20 @@ type Node struct {
 	// parts of headscale.
 	GivenName string `gorm:"type:varchar(63);unique_index"`
 	UserID    uint
-	User      User `gorm:"foreignKey:UserID"`
+	User      User `gorm:"constraint:OnDelete:CASCADE;"`
 
 	RegisterMethod string
 
 	ForcedTags StringList
 
 	// TODO(kradalby): This seems like irrelevant information?
-	AuthKeyID uint
-	AuthKey   *PreAuthKey
+	AuthKeyID *uint       `sql:"DEFAULT:NULL"`
+	AuthKey   *PreAuthKey `gorm:"constraint:OnDelete:SET NULL;"`
 
 	LastSeen *time.Time
 	Expiry   *time.Time
 
-	Routes []Route
+	Routes []Route `gorm:"constraint:OnDelete:CASCADE;"`
 
 	CreatedAt time.Time
 	UpdatedAt time.Time

hscontrol/types/preauth_key.go

@@ -14,11 +14,11 @@ type PreAuthKey struct {
 	ID        uint64 `gorm:"primary_key"`
 	Key       string
 	UserID    uint
-	User      User
+	User      User `gorm:"constraint:OnDelete:CASCADE;"`
 	Reusable  bool
-	Ephemeral bool `gorm:"default:false"`
-	Used      bool `gorm:"default:false"`
-	ACLTags   []PreAuthKeyACLTag
+	Ephemeral bool               `gorm:"default:false"`
+	Used      bool               `gorm:"default:false"`
+	ACLTags   []PreAuthKeyACLTag `gorm:"constraint:OnDelete:CASCADE;"`
 
 	CreatedAt  *time.Time
 	Expiration *time.Time