subsoil 0.2.0

Soil primitives foundation crate
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51

// This file is part of Soil.

// Copyright (C) Soil contributors.
// Copyright (C) Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: Apache-2.0 OR GPL-3.0-or-later WITH Classpath-exception-2.0

//! Aura (Authority-Round) digests
//!
//! This implements the digests for AuRa, to allow the private
//! `CompatibleDigestItem` trait to appear in public interfaces.

use super::AURA_ENGINE_ID;
use crate::consensus::slots::Slot;
use crate::runtime::generic::DigestItem;
use codec::{Codec, Encode};

/// A digest item which is usable with aura consensus.
pub trait CompatibleDigestItem<Signature>: Sized {
	/// Construct a digest item which contains a signature on the hash.
	fn aura_seal(signature: Signature) -> Self;

	/// If this item is an Aura seal, return the signature.
	fn as_aura_seal(&self) -> Option<Signature>;

	/// Construct a digest item which contains the slot number
	fn aura_pre_digest(slot: Slot) -> Self;

	/// If this item is an AuRa pre-digest, return the slot number
	fn as_aura_pre_digest(&self) -> Option<Slot>;
}

impl<Signature> CompatibleDigestItem<Signature> for DigestItem
where
	Signature: Codec,
{
	fn aura_seal(signature: Signature) -> Self {
		DigestItem::Seal(AURA_ENGINE_ID, signature.encode())
	}

	fn as_aura_seal(&self) -> Option<Signature> {
		self.seal_try_to(&AURA_ENGINE_ID)
	}

	fn aura_pre_digest(slot: Slot) -> Self {
		DigestItem::PreRuntime(AURA_ENGINE_ID, slot.encode())
	}

	fn as_aura_pre_digest(&self) -> Option<Slot> {
		self.pre_runtime_try_to(&AURA_ENGINE_ID)
	}
}