Trait pallet_session::SessionManager
source · pub trait SessionManager<ValidatorId> {
fn new_session(new_index: SessionIndex) -> Option<Vec<ValidatorId>>;
fn end_session(end_index: SessionIndex);
fn start_session(start_index: SessionIndex);
fn new_session_genesis(new_index: SessionIndex) -> Option<Vec<ValidatorId>> { ... }
}
Expand description
A trait for managing creation of new validator set.
Required Methods§
sourcefn new_session(new_index: SessionIndex) -> Option<Vec<ValidatorId>>
fn new_session(new_index: SessionIndex) -> Option<Vec<ValidatorId>>
Plan a new session, and optionally provide the new validator set.
Even if the validator-set is the same as before, if any underlying economic conditions have
changed (i.e. stake-weights), the new validator set must be returned. This is necessary for
consensus engines making use of the session pallet to issue a validator-set change so
misbehavior can be provably associated with the new economic conditions as opposed to the
old. The returned validator set, if any, will not be applied until new_index
. new_index
is strictly greater than from previous call.
The first session start at index 0.
new_session(session)
is guaranteed to be called before end_session(session-1)
. In other
words, a new session must always be planned before an ongoing one can be finished.
sourcefn end_session(end_index: SessionIndex)
fn end_session(end_index: SessionIndex)
End the session.
Because the session pallet can queue validator set the ending session can be lower than the last new session index.
sourcefn start_session(start_index: SessionIndex)
fn start_session(start_index: SessionIndex)
Start an already planned session.
The session start to be used for validation.
Provided Methods§
sourcefn new_session_genesis(new_index: SessionIndex) -> Option<Vec<ValidatorId>>
fn new_session_genesis(new_index: SessionIndex) -> Option<Vec<ValidatorId>>
Same as new_session
, but it this should only be called at genesis.
The session manager might decide to treat this in a different way. Default impl is simply
using new_session
.