feat: Enhance remote room leave handling

src/admin/user/commands.rs

@@ -1,4 +1,7 @@
-use std::{collections::BTreeMap, fmt::Write as _};
+use std::{
+	collections::{BTreeMap, HashSet},
+	fmt::Write as _,
+};
 
 use api::client::{
 	full_user_deactivate, join_room_by_id_helper, leave_all_rooms, leave_room, remote_leave_room,
@@ -12,7 +15,7 @@ use conduwuit::{
 };
 use futures::{FutureExt, StreamExt};
 use ruma::{
-	OwnedEventId, OwnedRoomId, OwnedRoomOrAliasId, OwnedUserId, UserId,
+	OwnedEventId, OwnedRoomId, OwnedRoomOrAliasId, OwnedServerName, OwnedUserId, UserId,
 	events::{
 		RoomAccountDataEventType, StateEventType,
 		room::{
@@ -950,23 +953,38 @@ pub(super) async fn force_leave_remote_room(
 	&self,
 	user_id: String,
 	room_id: OwnedRoomOrAliasId,
+	via: Option<String>,
 ) -> Result {
 	let user_id = parse_local_user_id(self.services, &user_id)?;
-	let (room_id, _) = self
+	let (room_id, vias_raw) = self
 		.services
 		.rooms
 		.alias
-		.resolve_with_servers(&room_id, None)
+		.resolve_with_servers(
+			&room_id,
+			if let Some(v) = via.clone() {
+				Some(vec![OwnedServerName::parse(v)?])
+			} else {
+				None
+			},
+		)
 		.await?;
 
 	assert!(
 		self.services.globals.user_is_local(&user_id),
 		"Parsed user_id must be a local user"
 	);
-	remote_leave_room(self.services, &user_id, &room_id, None)
+	let mut vias: HashSet<OwnedServerName> = HashSet::new();
+	if let Some(via) = via {
+		vias.insert(OwnedServerName::parse(via)?);
+	}
+	for server in vias_raw {
+		vias.insert(server);
+	}
+	remote_leave_room(self.services, &user_id, &room_id, None, vias)
 		.boxed()
 		.await?;
 
-	self.write_str(&format!("{user_id} has been joined to {room_id}.",))
+	self.write_str(&format!("{user_id} successfully left {room_id} via remote server."))
 		.await
 }

src/admin/user/mod.rs

@@ -107,6 +107,7 @@ pub enum UserCommand {
 	ForceLeaveRemoteRoom {
 		user_id: String,
 		room_id: OwnedRoomOrAliasId,
+		via: Option<String>,
 	},
 
 	/// - Forces the specified user to drop their power levels to the room

src/api/client/membership/leave.rs

@@ -131,9 +131,10 @@ pub async fn leave_room(
 
 	// Ask a remote server if we don't have this room and are not knocking on it
 	if dont_have_room.and(not_knocked).await {
-		if let Err(e) = remote_leave_room(services, user_id, room_id, reason.clone())
+		if let Err(e) =
-			.boxed()
+			remote_leave_room(services, user_id, room_id, reason.clone(), HashSet::new())
-			.await
+				.boxed()
+				.await
 		{
 			warn!(%user_id, "Failed to leave room {room_id} remotely: {e}");
 			// Don't tell the client about this error
@@ -215,22 +216,25 @@ pub async fn leave_room(
 	Ok(())
 }
 
-pub async fn remote_leave_room(
+pub async fn remote_leave_room<S: ::std::hash::BuildHasher>(
 	services: &Services,
 	user_id: &UserId,
 	room_id: &RoomId,
 	reason: Option<String>,
+	mut servers: HashSet<OwnedServerName, S>,
 ) -> Result<()> {
 	let mut make_leave_response_and_server =
 		Err!(BadServerResponse("No remote server available to assist in leaving {room_id}."));
 
-	let mut servers: HashSet<OwnedServerName> = services
+	servers.extend(
-		.rooms
+		services
-		.state_cache
+			.rooms
-		.servers_invite_via(room_id)
+			.state_cache
-		.map(ToOwned::to_owned)
+			.servers_invite_via(room_id)
-		.collect()
+			.map(ToOwned::to_owned)
-		.await;
+			.collect::<HashSet<OwnedServerName>>()
+			.await,
+	);
 
 	match services
 		.rooms
@@ -277,6 +281,11 @@ pub async fn remote_leave_room(
 	if let Some(room_id_server_name) = room_id.server_name() {
 		servers.insert(room_id_server_name.to_owned());
 	}
+	if servers.is_empty() {
+		return Err!(BadServerResponse(warn!(
+			"No remote servers found to assist in leaving {room_id}."
+		)));
+	}
 
 	debug_info!("servers in remote_leave_room: {servers:?}");
 
@@ -284,7 +293,7 @@ pub async fn remote_leave_room(
 		let make_leave_response = services
 			.sending
 			.send_federation_request(
-				&remote_server,
+				remote_server.as_ref(),
 				federation::membership::prepare_leave_event::v1::Request {
 					room_id: room_id.to_owned(),
 					user_id: user_id.to_owned(),
@@ -292,11 +301,21 @@ pub async fn remote_leave_room(
 			)
 			.await;
 
-		make_leave_response_and_server = make_leave_response.map(|r| (r, remote_server));
+		let error = make_leave_response.as_ref().err().map(|e| e.to_string());
+		make_leave_response_and_server = make_leave_response.map(|r| (r, remote_server.clone()));
 
 		if make_leave_response_and_server.is_ok() {
+			debug_info!(
+				"Received make_leave_response from {} for leaving {room_id}",
+				remote_server
+			);
 			break;
 		}
+		debug_warn!(
+			"Failed to get make_leave_response from {} for leaving {room_id}: {}",
+			remote_server,
+			error.unwrap()
+		);
 	}
 
 	let (make_leave_response, remote_server) = make_leave_response_and_server?;
@@ -304,13 +323,14 @@ pub async fn remote_leave_room(
 	let Some(room_version_id) = make_leave_response.room_version else {
 		return Err!(BadServerResponse(warn!(
 			"No room version was returned by {remote_server} for {room_id}, room version is \
-			 likely not supported by conduwuit"
+			 likely not supported by continuwuity"
 		)));
 	};
 
 	if !services.server.supported_room_version(&room_version_id) {
 		return Err!(BadServerResponse(warn!(
-			"Remote room version {room_version_id} for {room_id} is not supported by conduwuit",
+			"Remote room version {room_version_id} for {room_id} is not supported by \
+			 continuwuity",
 		)));
 	}