// 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/>.
//
//! Error handling related code and Error/Result definitions.
use polkadot_node_network_protocol::PeerId;
use polkadot_node_subsystem::{RuntimeApiError, SubsystemError};
use polkadot_node_subsystem_util::{
backing_implicit_view::FetchError as ImplicitViewFetchError, runtime,
};
use polkadot_primitives::{CandidateHash, Hash, Id as ParaId};
use futures::channel::oneshot;
use crate::LOG_TARGET;
/// General result.
pub type Result<T> = std::result::Result<T, Error>;
/// Result for non-fatal only failures.
pub type JfyiErrorResult<T> = std::result::Result<T, JfyiError>;
/// Result for fatal only failures.
pub type FatalResult<T> = std::result::Result<T, FatalError>;
use fatality::Nested;
#[allow(missing_docs)]
#[fatality::fatality(splitable)]
pub enum Error {
#[fatal]
#[error("Requester receiver stream finished")]
RequesterReceiverFinished,
#[fatal]
#[error("Responder receiver stream finished")]
ResponderReceiverFinished,
#[fatal]
#[error("Spawning subsystem task failed")]
SpawnTask(#[source] SubsystemError),
#[fatal]
#[error("Receiving message from overseer failed")]
SubsystemReceive(#[source] SubsystemError),
#[fatal(forward)]
#[error("Error while accessing runtime information")]
Runtime(#[from] runtime::Error),
#[error("RuntimeAPISubsystem channel closed before receipt")]
RuntimeApiUnavailable(#[source] oneshot::Canceled),
#[error("Fetching persisted validation data for para {0:?}, {1:?}")]
FetchPersistedValidationData(ParaId, RuntimeApiError),
#[error("Fetching session index failed {0:?}")]
FetchSessionIndex(RuntimeApiError),
#[error("Fetching session info failed {0:?}")]
FetchSessionInfo(RuntimeApiError),
#[error("Fetching disabled validators failed {0:?}")]
FetchDisabledValidators(runtime::Error),
#[error("Fetching validator groups failed {0:?}")]
FetchValidatorGroups(RuntimeApiError),
#[error("Fetching claim queue failed {0:?}")]
FetchClaimQueue(RuntimeApiError),
#[error("Attempted to share statement when not a validator or not assigned")]
InvalidShare,
#[error("Relay parent could not be found in active heads")]
NoSuchHead(Hash),
#[error("Message from not connected peer")]
NoSuchPeer(PeerId),
#[error("Peer requested data for candidate it never received a notification for (malicious?)")]
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,
// Failed to activate leaf due to a fetch error.
#[error("Implicit view failure while activating leaf")]
ActivateLeafFailure(ImplicitViewFetchError),
}
/// 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,
warn_freq: &mut gum::Freq,
) -> std::result::Result<(), FatalError> {
match result.into_nested()? {
Err(jfyi) => {
match jfyi {
JfyiError::RequestedUnannouncedCandidate(_, _) =>
gum::warn!(target: LOG_TARGET, error = %jfyi, ctx),
_ =>
gum::warn_if_frequent!(freq: warn_freq, max_rate: gum::Times::PerHour(100), target: LOG_TARGET, error = %jfyi, ctx),
}
Ok(())
},
Ok(()) => Ok(()),
}
}