Trait polkadot_runtime_common::traits::Leaser[−][src]

pub trait Leaser<BlockNumber> {
    type AccountId;
    type LeasePeriod;
    type Currency: ReservableCurrency<Self::AccountId>;
    fn lease_out(
        para: ParaId, 
        leaser: &Self::AccountId, 
        amount: <Self::Currency as Currency<Self::AccountId>>::Balance, 
        period_begin: Self::LeasePeriod, 
        period_count: Self::LeasePeriod
    ) -> Result<(), LeaseError>;

    fn deposit_held(
        para: ParaId, 
        leaser: &Self::AccountId
    ) -> <Self::Currency as Currency<Self::AccountId>>::Balance;

    fn lease_period_length() -> (BlockNumber, BlockNumber);

    fn lease_period_index(
        block: BlockNumber
    ) -> Option<(Self::LeasePeriod, bool)>;

    fn already_leased(
        para_id: ParaId, 
        first_period: Self::LeasePeriod, 
        last_period: Self::LeasePeriod
    ) -> bool;
}
Expand description

Lease manager. Used by the auction module to handle parachain slot leases.

Associated Types

An account identifier for a leaser.

The measurement type for counting lease periods (generally just a BlockNumber).

The currency type in which the lease is taken.

Required methods

Lease a new parachain slot for para.

leaser shall have a total of amount balance reserved by the implementer of this trait.

Note: The implementer of the trait (the leasing system) is expected to do all reserve/unreserve calls. The caller of this trait SHOULD NOT pre-reserve the deposit (though should ensure that it is reservable).

The lease will last from period_begin for period_count lease periods. It is undefined if the para already has a slot leased during those periods.

Returns Err in the case of an error, and in which case nothing is changed.

Return the amount of balance currently held in reserve on leaser’s account for leasing para. This won’t go down outside a lease period.

The length of a lease period, and any offset which may be introduced. This is only used in benchmarking to automate certain calls.

Returns the lease period at block, and if this is the first block of a new lease period.

Will return None if the first lease period has not started yet, for example when an offset is placed.

Returns true if the parachain already has a lease in any of lease periods in the inclusive range [first_period, last_period], intersected with the unbounded range [current_lease_period..] .

Implementors