From e2f088c3718ddc4338b6871729c857c4b7422cf8 Mon Sep 17 00:00:00 2001 From: Jeffrey Czyz Date: Thu, 19 Aug 2021 11:21:42 -0500 Subject: [PATCH] Expand and format BackgroundProcessor docs --- lightning-background-processor/src/lib.rs | 43 ++++++++++++++++------- 1 file changed, 30 insertions(+), 13 deletions(-) diff --git a/lightning-background-processor/src/lib.rs b/lightning-background-processor/src/lib.rs index 45b33fd1..7604ba1e 100644 --- a/lightning-background-processor/src/lib.rs +++ b/lightning-background-processor/src/lib.rs @@ -26,20 +26,28 @@ use std::thread::JoinHandle; use std::time::{Duration, Instant}; use std::ops::Deref; -/// BackgroundProcessor takes care of tasks that (1) need to happen periodically to keep +/// `BackgroundProcessor` takes care of tasks that (1) need to happen periodically to keep /// Rust-Lightning running properly, and (2) either can or should be run in the background. Its /// responsibilities are: -/// * Monitoring whether the ChannelManager needs to be re-persisted to disk, and if so, +/// * Processing [`Event`]s with a user-provided [`EventHandler`]. +/// * Monitoring whether the [`ChannelManager`] needs to be re-persisted to disk, and if so, /// writing it to disk/backups by invoking the callback given to it at startup. -/// ChannelManager persistence should be done in the background. -/// * Calling `ChannelManager::timer_tick_occurred()` and -/// `PeerManager::timer_tick_occurred()` every minute (can be done in the -/// background). +/// [`ChannelManager`] persistence should be done in the background. +/// * Calling [`ChannelManager::timer_tick_occurred`] and [`PeerManager::timer_tick_occurred`] +/// at the appropriate intervals. /// -/// Note that if ChannelManager persistence fails and the persisted manager becomes out-of-date, -/// then there is a risk of channels force-closing on startup when the manager realizes it's -/// outdated. However, as long as `ChannelMonitor` backups are sound, no funds besides those used -/// for unilateral chain closure fees are at risk. +/// It will also call [`PeerManager::process_events`] periodically though this shouldn't be relied +/// upon as doing so may result in high latency. +/// +/// # Note +/// +/// If [`ChannelManager`] persistence fails and the persisted manager becomes out-of-date, then +/// there is a risk of channels force-closing on startup when the manager realizes it's outdated. +/// However, as long as [`ChannelMonitor`] backups are sound, no funds besides those used for +/// unilateral chain closure fees are at risk. +/// +/// [`ChannelMonitor`]: lightning::chain::channelmonitor::ChannelMonitor +/// [`Event`]: lightning::util::events::Event #[must_use = "BackgroundProcessor will immediately stop on drop. It should be stored until shutdown."] pub struct BackgroundProcessor { stop_thread: Arc, @@ -99,21 +107,30 @@ impl BackgroundProcessor { /// `persist_manager` returns an error. In case of an error, the error is retrieved by calling /// either [`join`] or [`stop`]. /// - /// Typically, users should either implement [`ChannelManagerPersister`] to never return an - /// error or call [`join`] and handle any error that may arise. For the latter case, the - /// `BackgroundProcessor` must be restarted by calling `start` again after handling the error. + /// # Data Persistence /// /// `persist_manager` is responsible for writing out the [`ChannelManager`] to disk, and/or /// uploading to one or more backup services. See [`ChannelManager::write`] for writing out a /// [`ChannelManager`]. See [`FilesystemPersister::persist_manager`] for Rust-Lightning's /// provided implementation. /// + /// Typically, users should either implement [`ChannelManagerPersister`] to never return an + /// error or call [`join`] and handle any error that may arise. For the latter case, + /// `BackgroundProcessor` must be restarted by calling `start` again after handling the error. + /// + /// # Event Handling + /// + /// `event_handler` is responsible for handling events that users should be notified of (e.g., + /// payment failed). A user's [`EventHandler`] may be decorated with other handlers to implement + /// common functionality. See individual [`Event`]s for further details. + /// /// [top-level documentation]: Self /// [`join`]: Self::join /// [`stop`]: Self::stop /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager /// [`ChannelManager::write`]: lightning::ln::channelmanager::ChannelManager#impl-Writeable /// [`FilesystemPersister::persist_manager`]: lightning_persister::FilesystemPersister::persist_manager + /// [`Event`]: lightning::util::events::Event pub fn start< Signer: 'static + Sign, CF: 'static + Deref + Send + Sync, -- 2.30.2