refactor: Split sync v3 into multiple files

2026-05-26 20:49:55 +00:00 · 2025-10-22 09:31:08 -04:00
parent 99aadff38e
commit c85b5bb122
3 changed files with 605 additions and 553 deletions
@@ -0,0 +1,706 @@
+use std::collections::{BTreeMap, HashMap};
+
+use conduwuit::{
+	Result, at, err, extract_variant, is_equal_to,
+	matrix::{
+		Event,
+		pdu::{PduCount, PduEvent},
+	},
+	ref_at,
+	result::FlatOk,
+	utils::{
+		BoolExt, IterStream, ReadyExt, TryFutureExtExt,
+		future::OptionStream,
+		math::ruma_from_u64,
+		stream::{BroadbandExt, Tools, WidebandExt},
+	},
+};
+use conduwuit_service::{
+	Services,
+	rooms::{
+		lazy_loading,
+		lazy_loading::{Options, Witness},
+		short::ShortStateHash,
+	},
+};
+use futures::{
+	FutureExt, StreamExt, TryFutureExt,
+	future::{OptionFuture, join, join3, join4, try_join4},
+};
+use ruma::{
+	OwnedEventId, OwnedRoomId, OwnedUserId, RoomId, UserId,
+	api::client::sync::sync_events::{
+		UnreadNotificationsCount,
+		v3::{Ephemeral, JoinedRoom, RoomAccountData, RoomSummary, State as RoomState, Timeline},
+	},
+	events::{
+		AnyRawAccountDataEvent, AnySyncEphemeralRoomEvent, StateEventType,
+		TimelineEventType::*,
+		room::member::{MembershipState, RoomMemberEventContent},
+	},
+	serde::Raw,
+	uint,
+};
+use service::rooms::short::{ShortEventId, ShortStateKey};
+use tracing::trace;
+
+use super::{load_timeline, share_encrypted_room};
+use crate::client::{
+	TimelinePdus, ignored_filter,
+	sync::v3::{DeviceListUpdates, SyncContext},
+};
+
+#[tracing::instrument(
+	name = "joined",
+	level = "debug",
+	skip_all,
+	fields(
+		room_id = ?room_id,
+	),
+)]
+#[allow(clippy::too_many_arguments)]
+pub(super) async fn load_joined_room(
+	services: &Services,
+	SyncContext {
+		sender_user,
+		sender_device,
+		since,
+		next_batch,
+		full_state,
+		filter,
+	}: SyncContext<'_>,
+	ref room_id: OwnedRoomId,
+) -> Result<(JoinedRoom, DeviceListUpdates)> {
+	let mut device_list_updates = DeviceListUpdates::new();
+	let sincecount = since.map(PduCount::Normal);
+	let next_batchcount = PduCount::Normal(next_batch);
+
+	// the shortstatehash of the room's state right now
+	let current_shortstatehash = services
+		.rooms
+		.state
+		.get_room_shortstatehash(room_id)
+		.map_err(|_| err!(Database(error!("Room {room_id} has no state"))));
+
+	// the shortstatehash of what the room's state was when the `since` token was
+	// issued
+	let since_shortstatehash = OptionFuture::from(since.map(|since| {
+		services
+			.rooms
+			.user
+			.get_token_shortstatehash(room_id, since)
+			.ok()
+	}))
+	.map(|v| Ok(v.flatten()));
+
+	let timeline = load_timeline(
+		services,
+		sender_user,
+		room_id,
+		sincecount,
+		Some(next_batchcount),
+		10_usize,
+	);
+
+	let receipt_events = services
+		.rooms
+		.read_receipt
+		.readreceipts_since(room_id, since)
+		.filter_map(|(read_user, _, edu)| async move {
+			services
+				.users
+				.user_is_ignored(read_user, sender_user)
+				.await
+				.or_some((read_user.to_owned(), edu))
+		})
+		.collect::<HashMap<OwnedUserId, Raw<AnySyncEphemeralRoomEvent>>>()
+		.map(Ok);
+
+	let (current_shortstatehash, since_shortstatehash, timeline, receipt_events) =
+		try_join4(current_shortstatehash, since_shortstatehash, timeline, receipt_events)
+			.boxed()
+			.await?;
+
+	let TimelinePdus { pdus: timeline_pdus, limited } = timeline;
+	let is_initial_sync = since_shortstatehash.is_none();
+
+	let timeline_start_shortstatehash = async {
+		if let Some((_, pdu)) = timeline_pdus.first() {
+			if let Ok(shortstatehash) = services
+				.rooms
+				.state_accessor
+				.pdu_shortstatehash(&pdu.event_id)
+				.await
+			{
+				return shortstatehash;
+			}
+		}
+
+		current_shortstatehash
+	};
+
+	let last_notification_read: OptionFuture<_> = timeline_pdus
+		.is_empty()
+		.then(|| {
+			services
+				.rooms
+				.user
+				.last_notification_read(sender_user, room_id)
+		})
+		.into();
+
+	let since_sender_member: OptionFuture<_> = since_shortstatehash
+		.map(|short| {
+			services
+				.rooms
+				.state_accessor
+				.state_get_content(short, &StateEventType::RoomMember, sender_user.as_str())
+				.ok()
+		})
+		.into();
+
+	let is_encrypted_room = services
+		.rooms
+		.state_accessor
+		.state_get(current_shortstatehash, &StateEventType::RoomEncryption, "")
+		.is_ok();
+
+	let (
+		last_notification_read,
+		since_sender_member,
+		timeline_start_shortstatehash,
+		is_encrypted_room,
+	) = join4(
+		last_notification_read,
+		since_sender_member,
+		timeline_start_shortstatehash,
+		is_encrypted_room,
+	)
+	.await;
+
+	let joined_since_last_sync =
+		since_sender_member
+			.flatten()
+			.is_none_or(|content: RoomMemberEventContent| {
+				content.membership != MembershipState::Join
+			});
+
+	let lazy_loading_enabled = (filter.room.state.lazy_load_options.is_enabled()
+		|| filter.room.timeline.lazy_load_options.is_enabled())
+		&& !full_state;
+
+	let lazy_loading_context = &lazy_loading::Context {
+		user_id: sender_user,
+		device_id: Some(sender_device),
+		room_id,
+		token: since,
+		options: Some(&filter.room.state.lazy_load_options),
+	};
+
+	let lazy_loading_witness = OptionFuture::from(lazy_loading_enabled.then(|| {
+		let witness: Witness = timeline_pdus
+			.iter()
+			.map(ref_at!(1))
+			.map(Event::sender)
+			.map(Into::into)
+			.chain(receipt_events.keys().map(Into::into))
+			.collect();
+
+		services
+			.rooms
+			.lazy_loading
+			.witness_retain(witness, lazy_loading_context)
+	}))
+	.await;
+
+	/* replace with multiple steps
+		glossary for my own sanity:
+		- full state: every state event from the start of the room to the start of the timeline
+		- incremental state: state events from `since` to the start of the timeline
+		- state_events: the `state` key on the JSON object we return
+
+		if initial sync or full_state:
+			get full state
+			use full state as state_events
+		else if TL is limited:
+			get incremental state
+			use incremental state as state_events
+			if encryption is enabled:
+				use incremental state to extend device list
+		else:
+			state_events is empty
+		compute counts and heroes from state_events
+	*/
+	let mut state_events = if is_initial_sync || full_state {
+		// reset lazy loading state on initial sync
+		if is_initial_sync {
+			services
+				.rooms
+				.lazy_loading
+				.reset(lazy_loading_context)
+				.await;
+		}
+
+		calculate_state_initial(
+			services,
+			sender_user,
+			timeline_start_shortstatehash,
+			lazy_loading_witness.as_ref(),
+		)
+		.boxed()
+		.await?
+	} else if limited {
+		let state_incremental = calculate_state_incremental(
+			services,
+			sender_user,
+			since_shortstatehash,
+			timeline_start_shortstatehash,
+			lazy_loading_witness.as_ref(),
+		)
+		.boxed()
+		.await?;
+
+		// calculate device list updates for E2EE
+		if is_encrypted_room {
+			// add users with changed keys to the `changed` list
+			services
+				.users
+				.room_keys_changed(room_id, since, Some(next_batch))
+				.map(at!(0))
+				.map(ToOwned::to_owned)
+				.ready_for_each(|user_id| {
+					device_list_updates.changed.insert(user_id);
+				})
+				.await;
+
+			// add users who now share encrypted rooms to `changed` and
+			// users who no longer share encrypted rooms to `left`
+			for state_event in &state_incremental {
+				if state_event.kind == RoomMember {
+					let Some(content): Option<RoomMemberEventContent> =
+						state_event.get_content().ok()
+					else {
+						continue;
+					};
+
+					let Some(user_id): Option<OwnedUserId> = state_event
+						.state_key
+						.as_ref()
+						.and_then(|key| key.parse().ok())
+					else {
+						continue;
+					};
+
+					{
+						use MembershipState::*;
+
+						if matches!(content.membership, Leave | Join) {
+							let shares_encrypted_room = share_encrypted_room(
+								services,
+								sender_user,
+								&user_id,
+								Some(room_id),
+							)
+							.await;
+							match content.membership {
+								| Leave if !shares_encrypted_room => {
+									device_list_updates.left.insert(user_id);
+								},
+								| Join if joined_since_last_sync || shares_encrypted_room => {
+									device_list_updates.changed.insert(user_id);
+								},
+								| _ => (),
+							}
+						}
+					}
+				}
+			}
+		}
+
+		state_incremental
+	} else {
+		vec![]
+	};
+
+	// only compute room counts and heroes (aka the summary) if the room's members
+	// changed since the last sync
+	let (joined_member_count, invited_member_count, heroes) =
+		if state_events.iter().any(|event| event.kind == RoomMember) {
+			calculate_counts(services, room_id, sender_user).await?
+		} else {
+			(None, None, None)
+		};
+
+	let is_sender_membership = |pdu: &PduEvent| {
+		pdu.kind == StateEventType::RoomMember.into()
+			&& pdu
+				.state_key
+				.as_deref()
+				.is_some_and(is_equal_to!(sender_user.as_str()))
+	};
+
+	let joined_sender_member: Option<_> = (joined_since_last_sync && timeline_pdus.is_empty())
+		.then(|| {
+			state_events
+				.iter()
+				.position(is_sender_membership)
+				.map(|pos| state_events.swap_remove(pos))
+		})
+		.flatten();
+
+	let prev_batch = timeline_pdus
+		.first()
+		.map(at!(0))
+		.or_else(|| joined_sender_member.is_some().and(since).map(Into::into));
+
+	let timeline_pdus = timeline_pdus
+		.into_iter()
+		.stream()
+		.wide_filter_map(|item| ignored_filter(services, item, sender_user))
+		.map(at!(1))
+		.chain(joined_sender_member.into_iter().stream())
+		.map(Event::into_format)
+		.collect::<Vec<_>>();
+
+	let account_data_events = services
+		.account_data
+		.changes_since(Some(room_id), sender_user, since, Some(next_batch))
+		.ready_filter_map(|e| extract_variant!(e, AnyRawAccountDataEvent::Room))
+		.collect();
+
+	let send_notification_counts =
+		last_notification_read.is_none_or(|count| since.is_none_or(|since| count > since));
+
+	let notification_count: OptionFuture<_> = send_notification_counts
+		.then(|| {
+			services
+				.rooms
+				.user
+				.notification_count(sender_user, room_id)
+				.map(TryInto::try_into)
+				.unwrap_or(uint!(0))
+		})
+		.into();
+
+	let highlight_count: OptionFuture<_> = send_notification_counts
+		.then(|| {
+			services
+				.rooms
+				.user
+				.highlight_count(sender_user, room_id)
+				.map(TryInto::try_into)
+				.unwrap_or(uint!(0))
+		})
+		.into();
+
+	let typing_events = services
+		.rooms
+		.typing
+		.last_typing_update(room_id)
+		.and_then(|count| async move {
+			if since.is_some_and(|since| count <= since) {
+				return Ok(Vec::<Raw<AnySyncEphemeralRoomEvent>>::new());
+			}
+
+			let typings = services
+				.rooms
+				.typing
+				.typings_all(room_id, sender_user)
+				.await?;
+
+			Ok(vec![serde_json::from_str(&serde_json::to_string(&typings)?)?])
+		})
+		.unwrap_or(Vec::new());
+
+	let unread_notifications = join(notification_count, highlight_count);
+	let events = join3(timeline_pdus, account_data_events, typing_events);
+	let (unread_notifications, events) = join(unread_notifications, events).boxed().await;
+
+	let (room_events, account_data_events, typing_events) = events;
+	let (notification_count, highlight_count) = unread_notifications;
+
+	let last_privateread_update = if let Some(since) = since {
+		services
+			.rooms
+			.read_receipt
+			.last_privateread_update(sender_user, room_id)
+			.await > since
+	} else {
+		true
+	};
+
+	let private_read_event = if last_privateread_update {
+		services
+			.rooms
+			.read_receipt
+			.private_read_get(room_id, sender_user)
+			.await
+			.ok()
+	} else {
+		None
+	};
+
+	let edus: Vec<Raw<AnySyncEphemeralRoomEvent>> = receipt_events
+		.into_values()
+		.chain(typing_events.into_iter())
+		.chain(private_read_event.into_iter())
+		.collect();
+
+	// Save the state after this sync so we can send the correct state diff next
+	// sync
+	services
+		.rooms
+		.user
+		.associate_token_shortstatehash(room_id, next_batch, current_shortstatehash)
+		.await;
+
+	let joined_room = JoinedRoom {
+		account_data: RoomAccountData { events: account_data_events },
+		summary: RoomSummary {
+			joined_member_count: joined_member_count.map(ruma_from_u64),
+			invited_member_count: invited_member_count.map(ruma_from_u64),
+			heroes: heroes
+				.into_iter()
+				.flatten()
+				.map(TryInto::try_into)
+				.filter_map(Result::ok)
+				.collect(),
+		},
+		unread_notifications: UnreadNotificationsCount { highlight_count, notification_count },
+		timeline: Timeline {
+			limited,
+			prev_batch: prev_batch.as_ref().map(ToString::to_string),
+			events: room_events,
+		},
+		state: RoomState {
+			events: state_events.into_iter().map(Event::into_format).collect(),
+		},
+		ephemeral: Ephemeral { events: edus },
+		unread_thread_notifications: BTreeMap::new(),
+	};
+
+	Ok((joined_room, device_list_updates))
+}
+
+/// Calculate the "initial state", or all events from the start of the room up
+/// to (but not including) the `current_shortstatehash`. If
+/// `lazy_loading_witness` is `None`, lazy loading will be disabled.
+#[tracing::instrument(
+	name = "initial",
+	level = "trace",
+	skip_all,
+	fields(current_shortstatehash)
+)]
+#[allow(clippy::too_many_arguments)]
+async fn calculate_state_initial(
+	services: &Services,
+	sender_user: &UserId,
+	current_shortstatehash: ShortStateHash,
+	lazy_loading_witness: Option<&Witness>,
+) -> Result<Vec<PduEvent>> {
+	let (shortstatekeys, event_ids): (Vec<_>, Vec<_>) = services
+		.rooms
+		.state_accessor
+		.state_full_ids(current_shortstatehash)
+		.unzip()
+		.await;
+
+	trace!("event ids for initial sync @ {:?}: {:?}", current_shortstatehash, event_ids);
+
+	services
+		.rooms
+		.short
+		.multi_get_statekey_from_short(shortstatekeys.into_iter().stream())
+		.zip(event_ids.into_iter().stream())
+		.ready_filter_map(|item| Some((item.0.ok()?, item.1)))
+		.ready_filter_map(|((event_type, state_key), event_id)| {
+			let lazy = lazy_loading_witness.is_some_and(|witness| {
+				event_type == StateEventType::RoomMember
+					&& state_key.as_str().try_into().is_ok_and(|user_id: &UserId| {
+						sender_user != user_id && !witness.contains(user_id)
+					})
+			});
+
+			lazy.or_some(event_id)
+		})
+		.broad_filter_map(|event_id: OwnedEventId| async move {
+			services.rooms.timeline.get_pdu(&event_id).await.ok()
+		})
+		.collect()
+		.map(Ok)
+		.await
+}
+
+/// Calculate the "incremental state", or all events from the
+/// `since_shortstatehash` up to (but not including)
+/// the `current_shortstatehash`. If `lazy_loading_witness` is `None`, lazy
+/// loading will be disabled.
+#[tracing::instrument(name = "incremental", level = "trace", skip_all)]
+#[allow(clippy::too_many_arguments)]
+async fn calculate_state_incremental<'a>(
+	services: &Services,
+	sender_user: &'a UserId,
+	since_shortstatehash: Option<ShortStateHash>,
+	current_shortstatehash: ShortStateHash,
+	lazy_loading_witness: Option<&'a Witness>,
+) -> Result<Vec<PduEvent>> {
+	let since_shortstatehash = since_shortstatehash.unwrap_or(current_shortstatehash);
+
+	let state_get_shorteventid = |user_id: &'a UserId| {
+		services
+			.rooms
+			.state_accessor
+			.state_get_shortid(
+				current_shortstatehash,
+				&StateEventType::RoomMember,
+				user_id.as_str(),
+			)
+			.ok()
+	};
+
+	let lazy_state_ids: OptionFuture<_> = lazy_loading_witness
+		.map(|witness| {
+			StreamExt::into_future(
+				witness
+					.iter()
+					.stream()
+					.broad_filter_map(|user_id| state_get_shorteventid(user_id)),
+			)
+		})
+		.into();
+
+	let state_diff_shortids = services
+		.rooms
+		.state_accessor
+		.state_added((since_shortstatehash, current_shortstatehash))
+		.boxed();
+
+	state_diff_shortids
+		.broad_filter_map(|(shortstatekey, shorteventid)| async move {
+			if lazy_loading_witness.is_none() {
+				return Some(shorteventid);
+			}
+
+			lazy_filter(services, sender_user, shortstatekey, shorteventid).await
+		})
+		.chain(lazy_state_ids.stream())
+		.broad_filter_map(|shorteventid| {
+			services
+				.rooms
+				.short
+				.get_eventid_from_short(shorteventid)
+				.ok()
+		})
+		.broad_filter_map(|event_id: OwnedEventId| async move {
+			services.rooms.timeline.get_pdu(&event_id).await.ok()
+		})
+		.collect::<Vec<_>>()
+		.map(Ok)
+		.await
+}
+
+async fn lazy_filter(
+	services: &Services,
+	sender_user: &UserId,
+	shortstatekey: ShortStateKey,
+	shorteventid: ShortEventId,
+) -> Option<ShortEventId> {
+	let (event_type, state_key) = services
+		.rooms
+		.short
+		.get_statekey_from_short(shortstatekey)
+		.await
+		.ok()?;
+
+	(event_type != StateEventType::RoomMember || state_key == sender_user.as_str())
+		.then_some(shorteventid)
+}
+
+async fn calculate_counts(
+	services: &Services,
+	room_id: &RoomId,
+	sender_user: &UserId,
+) -> Result<(Option<u64>, Option<u64>, Option<Vec<OwnedUserId>>)> {
+	let joined_member_count = services
+		.rooms
+		.state_cache
+		.room_joined_count(room_id)
+		.unwrap_or(0);
+
+	let invited_member_count = services
+		.rooms
+		.state_cache
+		.room_invited_count(room_id)
+		.unwrap_or(0);
+
+	let (joined_member_count, invited_member_count) =
+		join(joined_member_count, invited_member_count).await;
+
+	let small_room = joined_member_count.saturating_add(invited_member_count) <= 5;
+
+	let heroes: OptionFuture<_> = small_room
+		.then(|| calculate_heroes(services, room_id, sender_user))
+		.into();
+
+	Ok((Some(joined_member_count), Some(invited_member_count), heroes.await))
+}
+
+async fn calculate_heroes(
+	services: &Services,
+	room_id: &RoomId,
+	sender_user: &UserId,
+) -> Vec<OwnedUserId> {
+	services
+		.rooms
+		.timeline
+		.all_pdus(sender_user, room_id)
+		.ready_filter(|(_, pdu)| pdu.kind == RoomMember)
+		.fold_default(|heroes: Vec<_>, (_, pdu)| {
+			fold_hero(heroes, services, room_id, sender_user, pdu)
+		})
+		.await
+}
+
+async fn fold_hero(
+	mut heroes: Vec<OwnedUserId>,
+	services: &Services,
+	room_id: &RoomId,
+	sender_user: &UserId,
+	pdu: PduEvent,
+) -> Vec<OwnedUserId> {
+	let Some(user_id): Option<&UserId> =
+		pdu.state_key.as_deref().map(TryInto::try_into).flat_ok()
+	else {
+		return heroes;
+	};
+
+	if user_id == sender_user {
+		return heroes;
+	}
+
+	let Ok(content): Result<RoomMemberEventContent, _> = pdu.get_content() else {
+		return heroes;
+	};
+
+	// The membership was and still is invite or join
+	if !matches!(content.membership, MembershipState::Join | MembershipState::Invite) {
+		return heroes;
+	}
+
+	if heroes.iter().any(is_equal_to!(user_id)) {
+		return heroes;
+	}
+
+	let (is_invited, is_joined) = join(
+		services.rooms.state_cache.is_invited(user_id, room_id),
+		services.rooms.state_cache.is_joined(user_id, room_id),
+	)
+	.await;
+
+	if !is_joined && is_invited {
+		return heroes;
+	}
+
+	heroes.push(user_id.to_owned());
+	heroes
+}