Merge commit '392447f5c8f986ded2559a78457f4cd87942f393' into update-bridges-subtree-r/w

polkadot/bridges/relays/lib-substrate-relay/src/error.rs

@@ -0,0 +1,58 @@
+// Copyright 2019-2021 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/>.
+
+//! Relay errors.
+
+use relay_substrate_client as client;
+use sp_finality_grandpa::AuthorityList;
+use sp_runtime::traits::MaybeDisplay;
+use std::fmt::Debug;
+use thiserror::Error;
+
+/// Relay errors.
+#[derive(Error, Debug)]
+pub enum Error<Hash: Debug + MaybeDisplay, HeaderNumber: Debug + MaybeDisplay> {
+	/// Failed to submit signed extrinsic from to the target chain.
+	#[error("Failed to submit {0} transaction: {1:?}")]
+	SubmitTransaction(&'static str, client::Error),
+	/// Failed subscribe to justification stream of the source chain.
+	#[error("Failed to subscribe to {0} justifications: {1:?}")]
+	Subscribe(&'static str, client::Error),
+	/// Failed subscribe to read justification from the source chain (client error).
+	#[error("Failed to read {0} justification from the stream: {1}")]
+	ReadJustification(&'static str, client::Error),
+	/// Failed subscribe to read justification from the source chain (stream ended).
+	#[error("Failed to read {0} justification from the stream: stream has ended unexpectedly")]
+	ReadJustificationStreamEnded(&'static str),
+	/// Failed subscribe to decode justification from the source chain.
+	#[error("Failed to decode {0} justification: {1:?}")]
+	DecodeJustification(&'static str, codec::Error),
+	/// GRANDPA authorities read from the source chain are invalid.
+	#[error("Read invalid {0} authorities set: {1:?}")]
+	ReadInvalidAuthorities(&'static str, AuthorityList),
+	/// Failed to guess initial GRANDPA authorities at the given header of the source chain.
+	#[error("Failed to guess initial {0} GRANDPA authorities set id: checked all possible ids in range [0; {1}]")]
+	GuessInitialAuthorities(&'static str, HeaderNumber),
+	/// Failed to retrieve GRANDPA authorities at the given header from the source chain.
+	#[error("Failed to retrive {0} GRANDPA authorities set at header {1}: {2:?}")]
+	RetrieveAuthorities(&'static str, Hash, client::Error),
+	/// Failed to decode GRANDPA authorities at the given header of the source chain.
+	#[error("Failed to decode {0} GRANDPA authorities set at header {1}: {2:?}")]
+	DecodeAuthorities(&'static str, Hash, codec::Error),
+	/// Failed to retrieve header by the hash from the source chain.
+	#[error("Failed to retrieve {0} header with hash {1}: {:?}")]
+	RetrieveHeader(&'static str, Hash, client::Error),
+}