simplify get_pdu() interface; eliminate unconditional Arc

Signed-off-by: Jason Volk <jason@zemos.net>

src/service/rooms/event_handler/fetch_and_handle_outliers.rs

@@ -7,6 +7,7 @@ use std::{
 use conduit::{
 	debug, debug_error, implement, info, pdu, trace, utils::math::continue_exponential_backoff_secs, warn, PduEvent,
 };
+use futures::TryFutureExt;
 use ruma::{api::federation::event::get_event, CanonicalJsonValue, EventId, RoomId, RoomVersionId, ServerName};
 
 /// Find the event and auth it. Once the event is validated (steps 1 - 8)
@@ -42,7 +43,7 @@ pub(super) async fn fetch_and_handle_outliers<'a>(
 		// a. Look in the main timeline (pduid_pdu tree)
 		// b. Look at outlier pdu tree
 		// (get_pdu_json checks both)
-		if let Ok(local_pdu) = self.services.timeline.get_pdu(id).await {
+		if let Ok(local_pdu) = self.services.timeline.get_pdu(id).map_ok(Arc::new).await {
 			trace!("Found {id} in db");
 			events_with_auth_events.push((id, Some(local_pdu), vec![]));
 			continue;

src/service/rooms/event_handler/handle_incoming_pdu.rs

@@ -1,10 +1,11 @@
 use std::{
 	collections::{hash_map, BTreeMap},
+	sync::Arc,
 	time::Instant,
 };
 
 use conduit::{debug, err, implement, warn, Error, Result};
-use futures::FutureExt;
+use futures::{FutureExt, TryFutureExt};
 use ruma::{
 	api::client::error::ErrorKind, events::StateEventType, CanonicalJsonValue, EventId, RoomId, ServerName, UserId,
 };
@@ -79,6 +80,7 @@ pub async fn handle_incoming_pdu<'a>(
 		.services
 		.state_accessor
 		.room_state_get(room_id, &StateEventType::RoomCreate, "")
+		.map_ok(Arc::new)
 		.await?;
 
 	// Procure the room version

src/service/rooms/event_handler/handle_outlier_pdu.rs

@@ -4,7 +4,7 @@ use std::{
 };
 
 use conduit::{debug, debug_info, err, implement, trace, warn, Err, Error, PduEvent, Result};
-use futures::future::ready;
+use futures::{future::ready, TryFutureExt};
 use ruma::{
 	api::client::error::ErrorKind,
 	events::StateEventType,
@@ -94,7 +94,7 @@ pub(super) async fn handle_outlier_pdu<'a>(
 	// Build map of auth events
 	let mut auth_events = HashMap::with_capacity(incoming_pdu.auth_events.len());
 	for id in &incoming_pdu.auth_events {
-		let Ok(auth_event) = self.services.timeline.get_pdu(id).await else {
+		let Ok(auth_event) = self.services.timeline.get_pdu(id).map_ok(Arc::new).await else {
 			warn!("Could not find auth event {id}");
 			continue;
 		};

src/service/rooms/event_handler/mod.rs

@@ -17,7 +17,11 @@ use std::{
 	time::Instant,
 };
 
-use conduit::{utils::MutexMap, Err, PduEvent, Result, Server};
+use conduit::{
+	utils::{MutexMap, TryFutureExtExt},
+	Err, PduEvent, Result, Server,
+};
+use futures::TryFutureExt;
 use ruma::{
 	events::room::create::RoomCreateEventContent, state_res::RoomVersion, EventId, OwnedEventId, OwnedRoomId, RoomId,
 	RoomVersionId,
@@ -94,7 +98,12 @@ impl Service {
 	async fn event_exists(&self, event_id: Arc<EventId>) -> bool { self.services.timeline.pdu_exists(&event_id).await }
 
 	async fn event_fetch(&self, event_id: Arc<EventId>) -> Option<Arc<PduEvent>> {
-		self.services.timeline.get_pdu(&event_id).await.ok()
+		self.services
+			.timeline
+			.get_pdu(&event_id)
+			.map_ok(Arc::new)
+			.ok()
+			.await
 	}
 }