Send statements to own backing group first (#2927)

* Factor out runtime module into utils. * First fatal error design. * Better error handling infra. * Error handling cleanup. * Send to peers of our group first. * Finish backing group prioritization. * Little cleanup. * More cleanup. * Forgot to checkin error.rs. * Notes. * Runtime -> RuntimeInfo * qed in debug assert. * PolkaErr -> Fault.
2026-04-26 19:17:58 +00:00 · 2021-04-27 21:47:32 +02:00
parent 36bd876311
commit c86a774b9d
17 changed files with 1031 additions and 280 deletions
@@ -0,0 +1,122 @@
+// Copyright 2021 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/>.
+//
+
+//! Error handling related code and Error/Result definitions.
+
+use polkadot_node_network_protocol::PeerId;
+use polkadot_primitives::v1::{CandidateHash, Hash};
+use polkadot_subsystem::SubsystemError;
+use thiserror::Error;
+
+use polkadot_node_subsystem_util::{Fault, runtime, unwrap_non_fatal};
+
+use crate::LOG_TARGET;
+
+/// General result.
+pub type Result<T> = std::result::Result<T, Error>;
+/// Result for non fatal only failures.
+pub type NonFatalResult<T> = std::result::Result<T, NonFatal>;
+/// Result for fatal only failures.
+pub type FatalResult<T> = std::result::Result<T, Fatal>;
+
+/// Errors for statement distribution.
+#[derive(Debug, Error)]
+#[error(transparent)]
+pub struct Error(pub Fault<NonFatal, Fatal>);
+
+impl From<NonFatal> for Error {
+	fn from(e: NonFatal) -> Self {
+		Self(Fault::from_non_fatal(e))
+	}
+}
+
+impl From<Fatal> for Error {
+	fn from(f: Fatal) -> Self {
+		Self(Fault::from_fatal(f))
+	}
+}
+
+impl From<runtime::Error> for Error {
+	fn from(o: runtime::Error) -> Self {
+		Self(Fault::from_other(o))
+	}
+}
+
+/// Fatal runtime errors.
+#[derive(Debug, Error)]
+pub enum Fatal {
+	/// Requester channel is never closed.
+	#[error("Requester receiver stream finished.")]
+	RequesterReceiverFinished,
+
+	/// Responder channel is never closed.
+	#[error("Responder receiver stream finished.")]
+	ResponderReceiverFinished,
+
+	/// Spawning a running task failed.
+	#[error("Spawning subsystem task failed")]
+	SpawnTask(#[source] SubsystemError),
+
+	/// Receiving subsystem message from overseer failed.
+	#[error("Receiving message from overseer failed")]
+	SubsystemReceive(#[source] SubsystemError),
+
+	/// Errors coming from runtime::Runtime.
+	#[error("Error while accessing runtime information")]
+	Runtime(#[from] #[source] runtime::Fatal),
+}
+
+/// Errors for fetching of runtime information.
+#[derive(Debug, Error)]
+pub enum NonFatal {
+	/// Errors coming from runtime::Runtime.
+	#[error("Error while accessing runtime information")]
+	Runtime(#[from] #[source] runtime::NonFatal),
+
+	/// Relay parent was not present in active heads.
+	#[error("Relay parent could not be found in active heads")]
+	NoSuchHead(Hash),
+
+	/// Peer requested statement data for candidate that was never announced to it.
+	#[error("Peer requested data for candidate it never received a notification for")]
+	RequestedUnannouncedCandidate(PeerId, CandidateHash),
+
+	/// A large statement status was requested, which could not be found.
+	#[error("Statement status does not exist")]
+	NoSuchLargeStatementStatus(Hash, CandidateHash),
+
+	/// A fetched large statement was requested, but could not be found.
+	#[error("Fetched large statement does not exist")]
+	NoSuchFetchedLargeStatement(Hash, CandidateHash),
+
+	/// Responder no longer waits for our data. (Should not happen right now.)
+	#[error("Oneshot `GetData` channel closed")]
+	ResponderGetDataCanceled,
+}
+
+/// Utility for eating top level errors and log them.
+///
+/// We basically always want to try and continue on error. This utility function is meant to
+/// consume top-level errors by simply logging them.
+pub fn log_error(result: Result<()>, ctx: &'static str)
+	-> FatalResult<()>
+{
+	if let Some(error) = unwrap_non_fatal(result.map_err(|e| e.0))? {
+		tracing::debug!(target: LOG_TARGET, error = ?error, ctx)
+	}
+	Ok(())
+}