Squashed commit of slava-async-bridge:

commit 657deb4cf4b90f24b9c5bfd62764b197776c262c
Author: Hernando Castano <castano.ha@gmail.com>
Date:   Wed Jan 29 20:14:20 2020 -0500

    Move Slava's bridge code into relays folder

commit 4868c42c7da959dde7252766996b3ed4e408e439
Author: Hernando Castano <castano.ha@gmail.com>
Date:   Wed Jan 29 20:01:06 2020 -0500

    Move files into `modules/ethereum`

commit d1093f3e4238acb1a1a020011452cb928d3f8d7a
Merge: 29dc6f9 bfd30ef
Author: Hernando Castano <castano.ha@gmail.com>
Date:   Wed Jan 29 19:59:27 2020 -0500

    Merge branch 'master' of slava-async-bridge

commit 29dc6f97b1b7d1db99086d35a5336f43d2f0f8af
Author: Hernando Castano <castano.ha@gmail.com>
Date:   Wed Jan 29 19:51:31 2020 -0500

    Squashed commit of the following:

    commit 265365920836bb1d286c9b48b1902a2de278fdd9
    Author: Hernando Castano <castano.ha@gmail.com>
    Date:   Wed Jan 29 19:51:15 2020 -0500

        Move hc-jp-bridge repo to different folder

    commit 8271991e95320baba70bd1cb9c4234d0ffd5b638
    Merge: 57d0811 304cbc5
    Author: Hernando Castano <castano.ha@gmail.com>
    Date:   Wed Jan 29 19:36:41 2020 -0500

        Merge branch 'hc-jp-bridge-module' of hc-jp-bridge-module

    commit 304cbc5f02d003ffa5404c1c01e461e5b8539888
    Author: Hernando Castano <HCastano@users.noreply.github.com>
    Date:   Wed Jan 29 00:38:27 2020 -0500

        Update bridge pallet to work with the (almost) lastest master (paritytech#4672)

        * Update decl_error usage

        * WIP: Update error handling to use DispatchResult

        * Get module compiling with new error handling

        * Make tests compile again

        Main change was updating the usage of InMemoryBackend

        * Move `sp-state-machine` into dev-dependencies

        * Bump dependencies to v2.0.0

        * Remove some stray comments

        * Appy code review suggestion

    commit 510cd6d96372688517496efa61773ea2839f8474
    Author: Hernando Castano <HCastano@users.noreply.github.com>
    Date:   Tue Dec 17 12:52:51 2019 -0500

        Move Bridge Pallet into FRAME (paritytech#4373)

        * Move `bridge` crate into `frame` folder

        * Make `bridge` pallet compile after `the-big-reorg`

    commit ab54e838ef75e6a3f68fd0944bf22598c10c552f
    Author: Hernando Castano <castano.ha@gmail.com>
    Date:   Mon Nov 11 21:56:40 2019 +0100

        Use new StorageProof type from paritytech#3834

    commit 8fc8911fd1b4acc2274c6863fb3dba91b30c90af
    Author: Hernando Castano <HCastano@users.noreply.github.com>
    Date:   Tue Nov 5 00:50:34 2019 +0100

        Verify Ancestry between Headers (paritytech#3963)

        * Create module for checking ancestry proofs

        * Use Vec of Headers instead of a HashMap

        * Move the ancestry verification into the lib.rs file

        * Change the proof format to exclude `child` and `ancestor` headers

        * Add a testing function for building header chains

        * Rename AncestorNotFound error to InvalidAncestryProof

        * Use ancestor hash instead of header when verifying ancestry

        * Clean up some stuff missed in the merge

    commit dbe85738b68358b790cf927b34a804b965a88f96
    or: Hernando Castano <HCastano@users.noreply.github.com>
    Date:   Fri Nov 1 15:41:58 2019 +0100

        Check given Grandpa validator set against set found in storage (paritytech#3915)

        * Make StorageProofChecker happy

        * Update some tests

        * Check given validator set against set found in storage

        * Use Finality Grandpa's Authority Id and Weight

        * Add better error handling

        * Use error type from decl_error! macro

    commit 31b09216603d3e9c21144ce8c0b6bf59307a4f97
    or: Hernando Castano <HCastano@users.noreply.github.com>
    Date:   Wed Oct 23 14:55:37 2019 +0200

        Make tests work after the changes introduced in paritytech#3793 (paritytech#3874)

        * Make tests work after the changes introduced in paritytech#3793

        * Remove unneccessary import

    commit bce6d804aa86504599ff912387295c58f846cbf3
    Author: Jim Posen <jim.posen@gmail.com>
    Date:   Thu Oct 10 12:18:58 2019 +0200

        Logic for checking Substrate proofs from within runtime module. (paritytech#3783)

    commit a7013e94b6c772c1d45a7cacbb445f73f6554fca
    Author: Hernando Castano <castano.ha@gmail.com>
    Date:   Fri Oct 4 15:21:00 2019 +0300

        Allow tracking of multiple bridges

    commit 3cf648242d631e32bd553a67df54bf5a48912839
    Author: Hernando Castano <castano.ha@gmail.com>
    Date:   Tue Oct 1 14:55:04 2019 +0200

        Add BridgeId => Bridge mapping

    commit 001c74c45072213e01857d0a2454379b447c5a76
    Author: Hernando Castano <castano.ha@gmail.com>
    Date:   Tue Oct 1 11:10:19 2019 +0200

        Get the mock runtime for tests set up

    commit 38443a1e8b424ed2f148eb95121d009f730e3b5a
    Author: Hernando Castano <castano.ha@gmail.com>
    Date:   Fri Sep 27 14:52:53 2019 +0200

        Clean up some warnings

    commit bdc3b01401e89c7111f8bf71f84c50750d25089f
    Author: Hernando Castano <castano.ha@gmail.com>
    Date:   Thu Sep 26 16:41:01 2019 +0200

        Add more skeleton code

    commit 26995efbf4bac2842eb2822322f7ad3c3e88feb8
    Author: Hernando Castano <castano.ha@gmail.com>
    Date:   Wed Sep 25 15:16:57 2019 +0200

        Create `bridge` module skeleton

commit bfd30ef8363b1483ef1107ae1eb958a4e944c93b
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Tue Dec 10 12:10:53 2019 +0300

    actually use signer from CLI to sign Substrate transactions

commit 504028eac60d9d14ba95b506cd355b0d2f405ce0
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Tue Dec 10 12:02:22 2019 +0300

    go offline for a bit on connection error

commit 446d0c8d20187dfd1beb173958ea28f2ad97887d
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Tue Dec 10 11:25:50 2019 +0300

    enable info logs by default

commit d039c60ec72bc91adfdad85442bc99a93b7f8e8d
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Tue Dec 10 11:12:51 2019 +0300

    support basic CLI arguments

commit 65c6d48e23576f36e8541878b920a03730226392
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Mon Dec 9 15:37:48 2019 +0300

    fix restart

commit 96e94c1c4b22d732078f8c401b872c5f8246c3fe
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Mon Dec 9 14:57:53 2019 +0300

    license

commit 68f4191e6cdd211ac8975e0b79f8a6f46a3ca953
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Mon Dec 9 14:56:05 2019 +0300

    restart sync when Substrate reorgs && we are unlucky

commit 29887c446167d580d73cc03a0b71c31890cafb51
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Mon Dec 9 13:49:31 2019 +0300

    only read genesis hash once

commit 832492b8393fe2063adf9c58c2b9e060dc3e4efb
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Mon Dec 9 13:23:26 2019 +0300

    changed TODO

commit 9dbc130e5fa036ae63d973819daf30f4ed6ffb5b
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Mon Dec 9 13:16:56 2019 +0300

    removed obsolete exit future

commit d03408cd8284eb0c61e7e96429b4f6199353e030
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Mon Dec 9 13:16:17 2019 +0300

    removed obsolete TODOs + moved a couple of TODOs to runtime module

commit ed8bec44b79f9a2ce829e59f10181368b2f42139
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Mon Dec 9 12:37:05 2019 +0300

    explained TODO fix

commit aa9c4c66ec2904eeb6072d654718b0ac0b7d8803
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Mon Dec 9 12:28:09 2019 +0300

    fix tx outcome serialization

commit 126f8f5484dac8c4af588ae86dc8855919d6c822
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Mon Dec 9 12:05:05 2019 +0300

    prune old ethereum headers when Substrate best header is too far in the future

commit c7bd301e631a44fe3263e188d0956081aa84f31e
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Fri Dec 6 12:51:50 2019 +0300

    fix trace

commit 549bb7acdb30cfdafe6c8600f0410212539ea63d
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Fri Dec 6 12:51:26 2019 +0300

    tx hashes are already a part of Block response

commit 7864017909f87ea36955d605a924c3c88bc88df3
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Thu Dec 5 12:29:37 2019 +0300

    submit bunch of headers at once + some fixes

commit 96485f85d38c144f0771f02ba692216a60356665
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Wed Dec 4 17:22:13 2019 +0300

    print status messages

commit ae0ec4c087136db653339537daab7f96a8c21b65
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Wed Dec 4 17:06:00 2019 +0300

    continue actual Substrate client implementation

commit 8146293740d70b88904568ff8e5acdfbadf06fd3
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Wed Dec 4 13:49:30 2019 +0300

    fix IncompleteHeader condition

commit 767c6201157dabcccf7f62e643681ca298224fb1
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Wed Dec 4 10:55:06 2019 +0300

    actual Substrate client implementation

commit 221fd4ccd2b1eea12c9dacf800d80e15ec115c1b
Author: Svyatoslav Nikolsky <svyatonik@gmail.com>
Date:   Wed Nov 20 17:28:13 2019 +0300

    initial commit

bridges/relays/ethereum/Cargo.toml

@@ -0,0 +1,32 @@
+[package]
+name = "async-bridge"
+version = "0.1.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
+
+[dependencies]
+ansi_term = "0.9"
+async-std = "1.0.1"
+async-stream = "0.2.0"
+clap = { version = "2.33.0", features = ["yaml"] }
+codec = { package = "parity-scale-codec", version = "1.0.0" }
+env_logger = "0.7.0"
+frame-system = { git = "https://github.com/svyatonik/substrate.git", branch = "bridge_runtime" }
+futures = "0.3.1"
+jsonrpsee-core = { git = "https://github.com/paritytech/jsonrpsee.git" }
+jsonrpsee-http = { git = "https://github.com/paritytech/jsonrpsee.git" }
+linked-hash-map = "0.5.2"
+log = "0.4.8"
+node-primitives = { git = "https://github.com/svyatonik/substrate.git", branch = "bridge_runtime" }
+node-runtime = { git = "https://github.com/svyatonik/substrate.git", branch = "bridge_runtime" }
+pallet-transaction-payment = { git = "https://github.com/svyatonik/substrate.git", branch = "bridge_runtime" }
+parking_lot = "0.9.0"
+rustc-hex = "2.0.1"
+serde = { version = "1.0.40", features = ["derive"] }
+serde_json = "1.0.40"
+sp-bridge-eth-poa = { git = "https://github.com/svyatonik/substrate.git", branch = "bridge_runtime" }
+sp-core = { git = "https://github.com/svyatonik/substrate.git", branch = "bridge_runtime" }
+sp-keyring = { git = "https://github.com/svyatonik/substrate.git", branch = "bridge_runtime" }
+sp-runtime = { git = "https://github.com/svyatonik/substrate.git", branch = "bridge_runtime" }
+time = "0.1"
+web3 = { git = "https://github.com/svyatonik/rust-web3.git", branch = "fix_receipt" }

bridges/relays/ethereum/README.md

@@ -0,0 +1,7 @@
+# PoA <> Substrate Bridge
+
+**DISCLAIMER:** *we recommend not using the bridge in "production" (to bridge significant amounts) just yet.
+it's missing a code audit and should still be considered alpha. we can't rule out that there are bugs that might result in loss of the bridged amounts.
+we'll update this disclaimer once that changes*
+
+These docs are very incomplete yet. Describe high-level goals here in the (near) future.

bridges/relays/ethereum/src/cli.yml

@@ -0,0 +1,33 @@
+name: ethsub-bridge
+version: "0.1.0"
+author: Parity Technologies <admin@parity.io>
+about: Parity Ethereum (PoA) <-> Substrate bridge
+args:
+    - eth-host:
+        long: eth-host
+        value_name: ETH_HOST
+        help: Connect to Ethereum node at given host.
+        takes_value: true
+    - eth-port:
+        long: eth-port
+        value_name: ETH_PORT
+        help: Connect to Ethereum node at given port.
+        takes_value: true
+    - sub-host:
+        long: sub-host
+        value_name: SUB_HOST
+        help: Connect to Substrate node at given host.
+        takes_value: true
+    - sub-port:
+        long: sub-port
+        value_name: SUB_PORT
+        help: Connect to Substrate node at given port.
+        takes_value: true
+    - sub-signer:
+        long: sub-signer
+        value_name: SUB_SIGNER
+        help: The SURI of secret key to use when transactions are submitted to the Substrate node.
+    - sub-signer-password:
+        long: sub-signer-password
+        value_name: SUB_SIGNER_PASSWORD
+        help: The password for the SURI of secret key to use when transactions are submitted to the Substrate node.

bridges/relays/ethereum/src/ethereum_client.rs

@@ -0,0 +1,170 @@
+// Copyright 2019 Parity Technologies (UK) Ltd.
+// This file is part of Parity-Bridge.
+
+// Parity-Bridge 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-Bridge 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-Bridge.  If not, see <http://www.gnu.org/licenses/>.
+
+use jsonrpsee_core::{client::ClientError, common::Params};
+use jsonrpsee_http::{HttpClient, RequestError, http_client};
+use serde::de::DeserializeOwned;
+use serde_json::{from_value, to_value};
+use crate::ethereum_sync_loop::MaybeConnectionError;
+use crate::ethereum_types::{H256, Header, HeaderId, Receipt, U64};
+
+/// Proof of hash serialization success.
+const HASH_SERIALIZATION_PROOF: &'static str = "hash serialization never fails; qed";
+/// Proof of integer serialization success.
+const INT_SERIALIZATION_PROOF: &'static str = "integer serialization never fails; qed";
+/// Proof of bool serialization success.
+const BOOL_SERIALIZATION_PROOF: &'static str = "bool serialization never fails; qed";
+
+/// Ethereum client type.
+pub type Client = HttpClient;
+
+/// All possible errors that can occur during interacting with Ethereum node.
+#[derive(Debug)]
+pub enum Error {
+	/// Request start failed.
+	StartRequestFailed(RequestError),
+	/// Request not found (should never occur?).
+	RequestNotFound,
+	/// Failed to receive response.
+	ResponseRetrievalFailed(ClientError<RequestError>),
+	/// Failed to parse response.
+	ResponseParseFailed(serde_json::Error),
+	/// We have received header with missing number and hash fields.
+	IncompleteHeader,
+	/// We have received receipt with missing gas_used field.
+	IncompleteReceipt,
+}
+
+impl MaybeConnectionError for Error {
+	fn is_connection_error(&self) -> bool {
+		match *self {
+			Error::StartRequestFailed(_) | Error::ResponseRetrievalFailed(_) => true,
+			_ => false,
+		}
+	}
+}
+
+/// Returns client that is able to call RPCs on Ethereum node.
+pub fn client(uri: &str) -> Client {
+	http_client(uri)
+}
+
+/// Retrieve best known block number from Ethereum node.
+pub async fn best_block_number(client: Client) -> (Client, Result<u64, Error>) {
+	let (client, result) = call_rpc::<U64>(
+		client,
+		"eth_blockNumber",
+		Params::None,
+	).await;
+	(client, result.map(|x| x.as_u64()))
+}
+
+/// Retrieve block header by its number from Ethereum node.
+pub async fn header_by_number(client: Client, number: u64) -> (Client, Result<Header, Error>) {
+	let (client, header) = call_rpc(
+		client,
+		"eth_getBlockByNumber",
+		Params::Array(vec![
+			to_value(U64::from(number)).expect(INT_SERIALIZATION_PROOF),
+			to_value(false).expect(BOOL_SERIALIZATION_PROOF),
+		]),
+	).await;
+	(client, header.and_then(|header: Header| match header.number.is_some() && header.hash.is_some() {
+		true => Ok(header),
+		false => Err(Error::IncompleteHeader),
+	}))
+}
+
+/// Retrieve block header by its hash from Ethereum node.
+pub async fn header_by_hash(client: Client, hash: H256) -> (Client, Result<Header, Error>) {
+	let (client, header) = call_rpc(
+		client,
+		"eth_getBlockByHash",
+		Params::Array(vec![
+			to_value(hash).expect(HASH_SERIALIZATION_PROOF),
+			to_value(false).expect(BOOL_SERIALIZATION_PROOF),
+		]),
+	).await;
+	(client, header.and_then(|header: Header| match header.number.is_none() && header.hash.is_none() {
+		true => Ok(header),
+		false => Err(Error::IncompleteHeader),
+	}))
+}
+
+/// Retrieve transactions receipts for given block.
+pub async fn transactions_receipts(
+	mut client: Client,
+	id: HeaderId,
+	transacactions: Vec<H256>,
+) -> (Client, Result<(HeaderId, Vec<Receipt>), Error>) {
+	let mut transactions_receipts = Vec::with_capacity(transacactions.len());
+	for transacaction in transacactions {
+		let (next_client, transaction_receipt) = transaction_receipt(client, transacaction).await;
+		let transaction_receipt = match transaction_receipt {
+			Ok(transaction_receipt) => transaction_receipt,
+			Err(error) => return (next_client, Err(error)),
+		};
+		transactions_receipts.push(transaction_receipt);
+		client = next_client;
+	}
+	(client, Ok((id, transactions_receipts)))
+}
+
+/// Retrieve transaction receipt by transaction hash.
+async fn transaction_receipt(client: Client, hash: H256) -> (Client, Result<Receipt, Error>) {
+	let (client, receipt) = call_rpc::<Receipt>(
+		client,
+		"eth_getTransactionReceipt",
+		Params::Array(vec![
+			to_value(hash).expect(HASH_SERIALIZATION_PROOF),
+		]),
+	).await;
+	(client, receipt.and_then(|receipt| {
+		match receipt.gas_used.is_some() {
+			true => Ok(receipt),
+			false => Err(Error::IncompleteReceipt),
+		}
+	}))
+}
+
+/// Calls RPC on Ethereum node.
+async fn call_rpc<T: DeserializeOwned>(
+	mut client: Client,
+	method: &'static str,
+	params: Params,
+) -> (Client, Result<T, Error>) {
+	async fn do_call_rpc<T: DeserializeOwned>(
+		client: &mut Client,
+		method: &'static str,
+		params: Params,
+	) -> Result<T, Error> {
+		let request_id = client
+			.start_request(method, params)
+			.await
+			.map_err(Error::StartRequestFailed)?;
+		// WARN: if there'll be need for executing >1 request at a time, we should avoid
+		// calling request_by_id
+		let response = client
+			.request_by_id(request_id)
+			.ok_or(Error::RequestNotFound)?
+			.await
+			.map_err(Error::ResponseRetrievalFailed)?;
+		from_value(response).map_err(Error::ResponseParseFailed)
+	}
+
+	let result = do_call_rpc(&mut client, method, params).await;
+	(client, result)
+}