referrerpolicy=no-referrer-when-downgrade
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
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162

// Copyright (C) Parity Technologies (UK) Ltd.
// This file is part of Polkadot.

// Polkadot is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// Polkadot is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.

//! Primitives for tracking collations-related data.

use std::collections::{HashSet, VecDeque};

use futures::{future::BoxFuture, stream::FuturesUnordered};

use polkadot_node_network_protocol::{
	request_response::{
		incoming::OutgoingResponse, v1 as protocol_v1, v2 as protocol_v2, IncomingRequest,
	},
	PeerId,
};
use polkadot_node_primitives::PoV;
use polkadot_node_subsystem::messages::ParentHeadData;
use polkadot_primitives::{
	vstaging::CandidateReceiptV2 as CandidateReceipt, CandidateHash, Hash, Id as ParaId,
};

/// The status of a collation as seen from the collator.
pub enum CollationStatus {
	/// The collation was created, but we did not advertise it to any validator.
	Created,
	/// The collation was advertised to at least one validator.
	Advertised,
	/// The collation was requested by at least one validator.
	Requested,
}

impl CollationStatus {
	/// Advance to the [`Self::Advertised`] status.
	///
	/// This ensures that `self` isn't already [`Self::Requested`].
	pub fn advance_to_advertised(&mut self) {
		if !matches!(self, Self::Requested) {
			*self = Self::Advertised;
		}
	}

	/// Advance to the [`Self::Requested`] status.
	pub fn advance_to_requested(&mut self) {
		*self = Self::Requested;
	}
}

/// A collation built by the collator.
pub struct Collation {
	/// Candidate receipt.
	pub receipt: CandidateReceipt,
	/// Proof to verify the state transition of the parachain.
	pub pov: PoV,
	/// Parent head-data (or just hash).
	pub parent_head_data: ParentHeadData,
	/// Collation status.
	pub status: CollationStatus,
}

/// Stores the state for waiting collation fetches per relay parent.
#[derive(Default)]
pub struct WaitingCollationFetches {
	/// A flag indicating that we have an ongoing request.
	/// This limits the number of collations being sent at any moment
	/// of time to 1 for each relay parent.
	///
	/// If set to `true`, any new request will be queued.
	pub collation_fetch_active: bool,
	/// The collation fetches waiting to be fulfilled.
	pub req_queue: VecDeque<VersionedCollationRequest>,
	/// All peers that are waiting or actively uploading.
	///
	/// We will not accept multiple requests from the same peer, otherwise our DoS protection of
	/// moving on to the next peer after `MAX_UNSHARED_UPLOAD_TIME` would be pointless.
	pub waiting_peers: HashSet<(PeerId, CandidateHash)>,
}

/// Backwards-compatible wrapper for incoming collations requests.
pub enum VersionedCollationRequest {
	V1(IncomingRequest<protocol_v1::CollationFetchingRequest>),
	V2(IncomingRequest<protocol_v2::CollationFetchingRequest>),
}

impl From<IncomingRequest<protocol_v1::CollationFetchingRequest>> for VersionedCollationRequest {
	fn from(req: IncomingRequest<protocol_v1::CollationFetchingRequest>) -> Self {
		Self::V1(req)
	}
}

impl From<IncomingRequest<protocol_v2::CollationFetchingRequest>> for VersionedCollationRequest {
	fn from(req: IncomingRequest<protocol_v2::CollationFetchingRequest>) -> Self {
		Self::V2(req)
	}
}

impl VersionedCollationRequest {
	/// Returns parachain id from the request payload.
	pub fn para_id(&self) -> ParaId {
		match self {
			VersionedCollationRequest::V1(req) => req.payload.para_id,
			VersionedCollationRequest::V2(req) => req.payload.para_id,
		}
	}

	/// Returns relay parent from the request payload.
	pub fn relay_parent(&self) -> Hash {
		match self {
			VersionedCollationRequest::V1(req) => req.payload.relay_parent,
			VersionedCollationRequest::V2(req) => req.payload.relay_parent,
		}
	}

	/// Returns id of the peer the request was received from.
	pub fn peer_id(&self) -> PeerId {
		match self {
			VersionedCollationRequest::V1(req) => req.peer,
			VersionedCollationRequest::V2(req) => req.peer,
		}
	}

	/// Sends the response back to requester.
	pub fn send_outgoing_response(
		self,
		response: OutgoingResponse<protocol_v1::CollationFetchingResponse>,
	) -> Result<(), ()> {
		match self {
			VersionedCollationRequest::V1(req) => req.send_outgoing_response(response),
			VersionedCollationRequest::V2(req) => req.send_outgoing_response(response),
		}
	}
}

/// Result of the finished background send-collation task.
///
/// Note that if the timeout was hit the request doesn't get
/// aborted, it only indicates that we should start processing
/// the next one from the queue.
pub struct CollationSendResult {
	/// Candidate's relay parent.
	pub relay_parent: Hash,
	/// Candidate hash.
	pub candidate_hash: CandidateHash,
	/// Peer id.
	pub peer_id: PeerId,
	/// Whether the max unshared timeout was hit.
	pub timed_out: bool,
}

pub type ActiveCollationFetches = FuturesUnordered<BoxFuture<'static, CollationSendResult>>;