polkadot_runtime_parachains/
util.rs

1// Copyright (C) Parity Technologies (UK) Ltd.
2// This file is part of Polkadot.
3
4// Polkadot is free software: you can redistribute it and/or modify
5// it under the terms of the GNU General Public License as published by
6// the Free Software Foundation, either version 3 of the License, or
7// (at your option) any later version.
8
9// Polkadot is distributed in the hope that it will be useful,
10// but WITHOUT ANY WARRANTY; without even the implied warranty of
11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12// GNU General Public License for more details.
13
14// You should have received a copy of the GNU General Public License
15// along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.
16
17//! Utilities that don't belong to any particular module but may draw
18//! on all modules.
19
20use alloc::{collections::btree_set::BTreeSet, vec::Vec};
21use frame_system::pallet_prelude::BlockNumberFor;
22use polkadot_primitives::{HeadData, Id as ParaId, PersistedValidationData, ValidatorIndex};
23
24use crate::{configuration, hrmp, paras};
25
26/// Make the persisted validation data for a particular parachain, a specified relay-parent and it's
27/// storage root.
28///
29/// This ties together the storage of several modules.
30pub fn make_persisted_validation_data<T: paras::Config + hrmp::Config>(
31	para_id: ParaId,
32	relay_parent_number: BlockNumberFor<T>,
33	relay_parent_storage_root: T::Hash,
34) -> Option<PersistedValidationData<T::Hash, BlockNumberFor<T>>> {
35	let config = configuration::ActiveConfig::<T>::get();
36
37	Some(PersistedValidationData {
38		parent_head: paras::Heads::<T>::get(&para_id)?,
39		relay_parent_number,
40		relay_parent_storage_root,
41		max_pov_size: config.max_pov_size,
42	})
43}
44
45/// Make the persisted validation data for a particular parachain, a specified relay-parent, its
46/// storage root and parent head data.
47pub fn make_persisted_validation_data_with_parent<T: configuration::Config>(
48	relay_parent_number: BlockNumberFor<T>,
49	relay_parent_storage_root: T::Hash,
50	parent_head: HeadData,
51) -> PersistedValidationData<T::Hash, BlockNumberFor<T>> {
52	let config = configuration::ActiveConfig::<T>::get();
53
54	PersistedValidationData {
55		parent_head,
56		relay_parent_number,
57		relay_parent_storage_root,
58		max_pov_size: config.max_pov_size,
59	}
60}
61
62/// Take an active subset of a set containing all validators.
63///
64/// First item in pair will be all items in set have indices found in the `active` indices set (in
65/// the order of the `active` vec, the second item will contain the rest, in the original order.
66///
67/// ```ignore
68/// 		split_active_subset(active, all).0 == take_active_subset(active, all)
69/// ```
70pub fn split_active_subset<T: Clone>(active: &[ValidatorIndex], all: &[T]) -> (Vec<T>, Vec<T>) {
71	let active_set: BTreeSet<_> = active.iter().cloned().collect();
72	// active result has ordering of active set.
73	let active_result = take_active_subset(active, all);
74	// inactive result preserves original ordering of `all`.
75	let inactive_result = all
76		.iter()
77		.enumerate()
78		.filter(|(i, _)| !active_set.contains(&ValidatorIndex(*i as _)))
79		.map(|(_, v)| v)
80		.cloned()
81		.collect();
82
83	if active_result.len() != active.len() {
84		log::warn!(
85			target: "runtime::parachains",
86			"Took active validators from set with wrong size.",
87		);
88	}
89
90	(active_result, inactive_result)
91}
92
93/// Uses `split_active_subset` and concatenates the inactive to the active vec.
94///
95/// ```ignore
96/// 		split_active_subset(active, all)[0..active.len()]) == take_active_subset(active, all)
97/// ```
98pub fn take_active_subset_and_inactive<T: Clone>(active: &[ValidatorIndex], all: &[T]) -> Vec<T> {
99	let (mut a, mut i) = split_active_subset(active, all);
100	a.append(&mut i);
101	a
102}
103
104/// Take the active subset of a set containing all validators.
105pub fn take_active_subset<T: Clone>(active: &[ValidatorIndex], set: &[T]) -> Vec<T> {
106	let subset: Vec<_> = active.iter().filter_map(|i| set.get(i.0 as usize)).cloned().collect();
107
108	if subset.len() != active.len() {
109		log::warn!(
110			target: "runtime::parachains",
111			"Took active validators from set with wrong size",
112		);
113	}
114
115	subset
116}
117
118#[cfg(test)]
119mod tests {
120
121	use alloc::vec::Vec;
122
123	use crate::util::{split_active_subset, take_active_subset};
124	use polkadot_primitives::ValidatorIndex;
125
126	#[test]
127	fn take_active_subset_is_compatible_with_split_active_subset() {
128		let active: Vec<_> = vec![ValidatorIndex(1), ValidatorIndex(7), ValidatorIndex(3)];
129		let validators = vec![9, 1, 6, 7, 4, 5, 2, 3, 0, 8];
130		let (selected, unselected) = split_active_subset(&active, &validators);
131		let selected2 = take_active_subset(&active, &validators);
132		assert_eq!(selected, selected2);
133		assert_eq!(unselected, vec![9, 6, 4, 5, 2, 0, 8]);
134		assert_eq!(selected, vec![1, 3, 7]);
135	}
136}
polkadot_runtime_parachains/util.rs

polkadot_runtime_parachains/
util.rs
