pallet_grandpa/
migrations.rs

1// This file is part of Substrate.
2
3// Copyright (C) Parity Technologies (UK) Ltd.
4// SPDX-License-Identifier: Apache-2.0
5
6// Licensed under the Apache License, Version 2.0 (the "License");
7// you may not use this file except in compliance with the License.
8// You may obtain a copy of the License at
9//
10// 	http://www.apache.org/licenses/LICENSE-2.0
11//
12// Unless required by applicable law or agreed to in writing, software
13// distributed under the License is distributed on an "AS IS" BASIS,
14// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15// See the License for the specific language governing permissions and
16// limitations under the License.
17
18use frame_support::{
19	traits::{Get, OnRuntimeUpgrade},
20	weights::Weight,
21};
22
23use crate::{Config, CurrentSetId, SetIdSession, LOG_TARGET};
24
25pub use v5::MigrateV4ToV5;
26
27/// Version 4.
28pub mod v4;
29mod v5;
30
31/// This migration will clean up all stale set id -> session entries from the
32/// `SetIdSession` storage map, only the latest `max_set_id_session_entries`
33/// will be kept.
34///
35/// This migration should be added with a runtime upgrade that introduces the
36/// `MaxSetIdSessionEntries` constant to the pallet (although it could also be
37/// done later on).
38pub struct CleanupSetIdSessionMap<T>(core::marker::PhantomData<T>);
39impl<T: Config> OnRuntimeUpgrade for CleanupSetIdSessionMap<T> {
40	fn on_runtime_upgrade() -> Weight {
41		// NOTE: since this migration will loop over all stale entries in the
42		// map we need to set some cutoff value, otherwise the migration might
43		// take too long to run. for scenarios where there are that many entries
44		// to cleanup a multiblock migration will be needed instead.
45		if CurrentSetId::<T>::get() > 25_000 {
46			log::warn!(
47				target: LOG_TARGET,
48				"CleanupSetIdSessionMap migration was aborted since there are too many entries to cleanup."
49			);
50
51			return T::DbWeight::get().reads(1)
52		}
53
54		cleanup_set_id_sesion_map::<T>()
55	}
56}
57
58fn cleanup_set_id_sesion_map<T: Config>() -> Weight {
59	let until_set_id = CurrentSetId::<T>::get().saturating_sub(T::MaxSetIdSessionEntries::get());
60
61	for set_id in 0..=until_set_id {
62		SetIdSession::<T>::remove(set_id);
63	}
64
65	T::DbWeight::get()
66		.reads(1)
67		.saturating_add(T::DbWeight::get().writes(until_set_id + 1))
68}
pallet_grandpa/migrations.rs

pallet_grandpa/
migrations.rs
