is it appropriate to use a Dbadapter per-request?

[pdonovan-merit]

is it appropriate to use a Dbadapter per-request?

[casbin-bot]

@tangyang9464 @JalinWang @imp2002

[JalinWang]

Every time an Enforcer is created with the adapter, it will load all the policies from the database. So if you have too many policies, initialization of the enforcer for each request is not recommended. However, initialization of the adapter and then calling e.SetAdapter() takes no cost other than authing connection with DB (note: if the content in DB is changed, you need to call e.LoadPolicy() manually 😣).
Transaction is only used in UpdateFilteredPolicies() and UpdatePolicies() by the `gorm-adapter. You can use functions other than these two.
BTW, I find the Gorm seems to have the support for nested transactions https://gorm.io/docs/transactions.html#Nested-Transactions . Perhaps you can write the following way(NOT tested, just a proof-of-concept):

func handler(……)
{
	tx = db.Begin()

	// tx.Create(...) some operations

	// begin nested transaction
	a, _ := adapter.NewAdapterByDB(tx)
	e.SetAdapter(a)

	e.UpdatePolicies(....) // do some operations

	a, _ = adapter.NewAdapterByDB(db)
	e.SetAdapter(a)

	// tx.Create(...)  // the left operations

	tx.Commit()
}

Hoping this will help you. @pdonovan-merit

[hsluoyz]

Closed as stale.