Sync Westend to Millau (#824)

* make finality verifier pallet instantiable

* add second instance of finality verifier pallet to the Millau runtime

* add Westend -> Millau headers relay

* use wss to connect to public westend nodes

* initialize with best_finalized_block

* typo

* Revert "initialize with best_finalized_block"

This reverts commit 954ed2832372d67618abc1a06d47e66faa93f674.

* pass VoterSet by ref

* new bridge initialization code

* loop upper bound

* Polkadot -> Westend

* fixed tests compilation

* default-features

* assert

bridges/relays/clients/westend/Cargo.toml

@@ -0,0 +1,25 @@
+[package]
+name = "relay-westend-client"
+version = "0.1.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
+license = "GPL-3.0-or-later WITH Classpath-exception-2.0"
+
+[dependencies]
+codec = { package = "parity-scale-codec", version = "2.0.0" }
+headers-relay = { path = "../../generic/headers" }
+relay-substrate-client = { path = "../substrate" }
+relay-utils = { path = "../../generic/utils" }
+
+# Bridge dependencies
+
+bp-westend = { path = "../../../primitives/chains/westend" }
+
+# Substrate Dependencies
+
+frame-system = { git = "https://github.com/paritytech/substrate", branch = "master" }
+frame-support = { git = "https://github.com/paritytech/substrate", branch = "master" }
+pallet-transaction-payment = { git = "https://github.com/paritytech/substrate", branch = "master" }
+sp-core = { git = "https://github.com/paritytech/substrate", branch = "master" }
+sp-keyring = { git = "https://github.com/paritytech/substrate", branch = "master" }
+sp-runtime = { git = "https://github.com/paritytech/substrate", branch = "master" }

bridges/relays/clients/westend/src/lib.rs

@@ -0,0 +1,47 @@
+// Copyright 2019-2020 Parity Technologies (UK) Ltd.
+// This file is part of Parity Bridges Common.
+
+// Parity Bridges Common 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.
+
+// Parity Bridges Common 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 Parity Bridges Common.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Types used to connect to the Westend chain.
+
+use relay_substrate_client::{Chain, ChainBase};
+use std::time::Duration;
+
+/// Westend header id.
+pub type HeaderId = relay_utils::HeaderId<bp_westend::Hash, bp_westend::BlockNumber>;
+
+/// Westend chain definition
+#[derive(Debug, Clone, Copy)]
+pub struct Westend;
+
+impl ChainBase for Westend {
+	type BlockNumber = bp_westend::BlockNumber;
+	type Hash = bp_westend::Hash;
+	type Hasher = bp_westend::Hasher;
+	type Header = bp_westend::Header;
+}
+
+impl Chain for Westend {
+	const NAME: &'static str = "Westend";
+	const AVERAGE_BLOCK_INTERVAL: Duration = Duration::from_secs(6);
+
+	type AccountId = bp_westend::AccountId;
+	type Index = bp_westend::Nonce;
+	type SignedBlock = bp_westend::SignedBlock;
+	type Call = ();
+}
+
+/// Westend header type used in headers sync.
+pub type SyncHeader = relay_substrate_client::SyncHeader<bp_westend::Header>;