Module migrations 

Implements storage migrations of pallet-session-validator-management.

Important: It is crucial to run the migrations when upgrading runtime to a version containing this pallet’s storage version. Failing to do so WILL break the chain and require a wipe or a rollback.

To schedule a migration, add it to the Executive definition for your runtime like this:

pub type Migrations = (
	pallet_session_validator_management::migrations::v1::LegacyToV1Migration<Runtime>,
    // ...
);
/// Executive: handles dispatch to the various modules.
pub type Executive = frame_executive::Executive<
	Runtime,
	Block,
	ChainContext,
	Runtime,
	AllPalletsWithSystem,
	Migrations,
>;

Each migration will be run only once, for the storage version for which it is defined, and will update the storage version number.

V1 (v1.6.0+)

Changes

This version changes the type used to store committee member information from a tuple (T::AuthorityId, T::AuthorityKeys) to a generic type T::CommitteeMember. This type can be arbitrary within normal constraints of Substrate runtime types and must implement the CommitteeMember trait. If your runtime uses authority-selection-inherents to select its committee, use the CommitteeMember type provided by this crate. A CommitteeMember implementation for the legacy (T::AuthorityId, T::AuthorityKeys) type is also provided and can be used.

Migration from Legacy

Migration logic is provided by the migrations::v1::LegacyToV1Migration migration. It assumes that the types T::AuthorityId and T::AuthorityKeys do not change as part of the same runtime upgrade. The only requirement for the new type T::CommitteeMember is to implement the trait From<(T::AuthorityId, T::AuthorityKeys)>.

Modules

authority_keys

Implements a re-usable migration for the authority keys type

v0

Legacy storage types used by version 0 of the pallet.

v1

Implements storage migration of the session-validator-management pallet from v0 to v1.