style(space-upgrades): Remove unused import left over from 6691b7672b

Before this change, only state events with an
empty state key would be cloned.
This allows m.space.child to be cloned appropriately.

src/api/client/room/upgrade.rs

@@ -2,10 +2,10 @@ use std::cmp::max;
 
 use axum::extract::State;
 use conduwuit::{
-	Err, Error, Event, Result, err, info,
+	Err, Error, Event, Result, debug, err, info,
 	matrix::{StateKey, pdu::PduBuilder},
 };
-use futures::StreamExt;
+use futures::{FutureExt, StreamExt};
 use ruma::{
 	CanonicalJsonObject, RoomId, RoomVersionId,
 	api::client::{error::ErrorKind, room::upgrade_room},
@@ -16,15 +16,16 @@ use ruma::{
 			power_levels::RoomPowerLevelsEventContent,
 			tombstone::RoomTombstoneEventContent,
 		},
+		space::child::{RedactedSpaceChildEventContent, SpaceChildEventContent},
 	},
 	int,
 };
 use serde_json::{json, value::to_raw_value};
 
-use crate::Ruma;
+use crate::router::Ruma;
 
 /// Recommended transferable state events list from the spec
-const TRANSFERABLE_STATE_EVENTS: &[StateEventType; 9] = &[
+const TRANSFERABLE_STATE_EVENTS: &[StateEventType; 11] = &[
 	StateEventType::RoomAvatar,
 	StateEventType::RoomEncryption,
 	StateEventType::RoomGuestAccess,
@@ -34,6 +35,9 @@ const TRANSFERABLE_STATE_EVENTS: &[StateEventType; 9] = &[
 	StateEventType::RoomPowerLevels,
 	StateEventType::RoomServerAcl,
 	StateEventType::RoomTopic,
+	// Not explicitly recommended in spec, but very useful.
+	StateEventType::SpaceChild,
+	StateEventType::SpaceParent, // TODO: m.room.policy?
 ];
 
 /// # `POST /_matrix/client/r0/rooms/{roomId}/upgrade`
@@ -50,10 +54,7 @@ pub(crate) async fn upgrade_room_route(
 	State(services): State<crate::State>,
 	body: Ruma<upgrade_room::v3::Request>,
 ) -> Result<upgrade_room::v3::Response> {
-	debug_assert!(
+	// TODO[v12]: Handle additional creators
-		TRANSFERABLE_STATE_EVENTS.is_sorted(),
-		"TRANSFERABLE_STATE_EVENTS is not sorted"
-	);
 	let sender_user = body.sender_user.as_ref().expect("user is authenticated");
 
 	if !services.server.supported_room_version(&body.new_version) {
@@ -128,7 +129,7 @@ pub(crate) async fn upgrade_room_route(
 				);
 			},
 			| _ => {
-				// "creator" key no longer exists in V11+ rooms
+				// "creator" key no longer exists in V11 rooms
 				create_event_content.remove("creator");
 			},
 		}
@@ -175,6 +176,7 @@ pub(crate) async fn upgrade_room_route(
 			&replacement_room,
 			&state_lock,
 		)
+		.boxed()
 		.await?;
 
 	// Join the new room
@@ -205,19 +207,30 @@ pub(crate) async fn upgrade_room_route(
 			&replacement_room,
 			&state_lock,
 		)
+		.boxed()
 		.await?;
 
 	// Replicate transferable state events to the new room
 	for event_type in TRANSFERABLE_STATE_EVENTS {
+		let state_keys = services
+			.rooms
+			.state_accessor
+			.room_state_keys(&body.room_id, event_type)
+			.await?;
+		for state_key in state_keys {
 			let event_content = match services
 				.rooms
 				.state_accessor
-			.room_state_get(&body.room_id, event_type, "")
+				.room_state_get(&body.room_id, event_type, &state_key)
 				.await
 			{
 				| Ok(v) => v.content().to_owned(),
 				| Err(_) => continue, // Skipping missing events.
 			};
+			if event_content.get() == "{}" {
+				// If the event content is empty, we skip it
+				continue;
+			}
 
 			services
 				.rooms
@@ -226,15 +239,17 @@ pub(crate) async fn upgrade_room_route(
 					PduBuilder {
 						event_type: event_type.to_string().into(),
 						content: event_content,
-					state_key: Some(StateKey::new()),
+						state_key: Some(StateKey::from(state_key)),
 						..Default::default()
 					},
 					sender_user,
 					&replacement_room,
 					&state_lock,
 				)
+				.boxed()
 				.await?;
 		}
+	}
 
 	// Moves any local aliases to the new room
 	let mut local_aliases = services
@@ -290,10 +305,90 @@ pub(crate) async fn upgrade_room_route(
 			&body.room_id,
 			&state_lock,
 		)
+		.boxed()
 		.await?;
 
 	drop(state_lock);
 
+	// Check if the old room has a space parent, and if so, whether we should update
+	// it (m.space.parent, room_id)
+	let parents = services
+		.rooms
+		.state_accessor
+		.room_state_keys(&body.room_id, &StateEventType::SpaceParent)
+		.await?;
+
+	for raw_space_id in parents {
+		let space_id = RoomId::parse(&raw_space_id)?;
+		let Ok(child) = services
+			.rooms
+			.state_accessor
+			.room_state_get_content::<SpaceChildEventContent>(
+				space_id,
+				&StateEventType::SpaceChild,
+				body.room_id.as_str(),
+			)
+			.await
+		else {
+			// If the space does not have a child event for this room, we can skip it
+			continue;
+		};
+		debug!(
+			"Updating space {space_id} child event for room {} to {replacement_room}",
+			&body.room_id
+		);
+		// First, drop the space's child event
+		let state_lock = services.rooms.state.mutex.lock(space_id).await;
+		debug!("Removing space child event for room {} in space {space_id}", &body.room_id);
+		services
+			.rooms
+			.timeline
+			.build_and_append_pdu(
+				PduBuilder {
+					event_type: StateEventType::SpaceChild.into(),
+					content: to_raw_value(&RedactedSpaceChildEventContent {})
+						.expect("event is valid, we just created it"),
+					state_key: Some(body.room_id.clone().as_str().into()),
+					..Default::default()
+				},
+				sender_user,
+				space_id,
+				&state_lock,
+			)
+			.boxed()
+			.await
+			.ok();
+		// Now, add a new child event for the replacement room
+		debug!("Adding space child event for room {replacement_room} in space {space_id}");
+		services
+			.rooms
+			.timeline
+			.build_and_append_pdu(
+				PduBuilder {
+					event_type: StateEventType::SpaceChild.into(),
+					content: to_raw_value(&SpaceChildEventContent {
+						via: vec![sender_user.server_name().to_owned()],
+						order: child.order,
+						suggested: child.suggested,
+					})
+					.expect("event is valid, we just created it"),
+					state_key: Some(replacement_room.as_str().into()),
+					..Default::default()
+				},
+				sender_user,
+				space_id,
+				&state_lock,
+			)
+			.boxed()
+			.await
+			.ok();
+		debug!(
+			"Finished updating space {space_id} child event for room {} to {replacement_room}",
+			&body.room_id
+		);
+		drop(state_lock);
+	}
+
 	// Return the replacement room id
 	Ok(upgrade_room::v3::Response { replacement_room })
 }

src/service/rooms/state_accessor/room_state.rs

@@ -91,3 +91,22 @@ pub async fn room_state_get(
 		.and_then(|shortstatehash| self.state_get(shortstatehash, event_type, state_key))
 		.await
 }
+
+/// Returns all state keys for the given `room_id` and `event_type`.
+#[implement(super::Service)]
+#[tracing::instrument(skip(self), level = "debug")]
+pub async fn room_state_keys(
+	&self,
+	room_id: &RoomId,
+	event_type: &StateEventType,
+) -> Result<Vec<String>> {
+	let shortstatehash = self.services.state.get_room_shortstatehash(room_id).await?;
+
+	let state_keys: Vec<String> = self
+		.state_keys(shortstatehash, event_type)
+		.map(|state_key| state_key.to_string())
+		.collect()
+		.await;
+
+	Ok(state_keys)
+}