feat: Allow room moderators to view redacted event content (MSC2815)

src/service/rooms/timeline/data.rs

@@ -8,6 +8,7 @@ use conduwuit::{
 use database::{Database, Deserialized, Json, KeyVal, Map};
 use futures::{FutureExt, Stream, TryFutureExt, TryStreamExt, future::select_ok, pin_mut};
 use ruma::{CanonicalJsonObject, EventId, OwnedUserId, RoomId, api::Direction};
+use serde_json::value::RawValue as RawJsonValue;
 
 use super::{PduId, RawPduId};
 use crate::{Dep, rooms, rooms::short::ShortRoomId};
@@ -16,6 +17,7 @@ pub(super) struct Data {
 	eventid_outlierpdu: Arc<Map>,
 	eventid_pduid: Arc<Map>,
 	pduid_pdu: Arc<Map>,
+	pduid_unredactedcontent: Arc<Map>,
 	roomid_lasttimelinecount: Arc<Map>,
 	userroomid_highlightcount: Arc<Map>,
 	userroomid_notificationcount: Arc<Map>,
@@ -36,6 +38,7 @@ impl Data {
 			eventid_outlierpdu: db["eventid_outlierpdu"].clone(),
 			eventid_pduid: db["eventid_pduid"].clone(),
 			pduid_pdu: db["pduid_pdu"].clone(),
+			pduid_unredactedcontent: db["pduid_unredactedcontent"].clone(),
 			roomid_lasttimelinecount: db["roomid_lasttimelinecount"].clone(),
 			userroomid_highlightcount: db["userroomid_highlightcount"].clone(),
 			userroomid_notificationcount: db["userroomid_notificationcount"].clone(),
@@ -234,6 +237,20 @@ impl Data {
 		Ok(())
 	}
 
+	pub(super) fn save_unredacted_content(&self, pdu_id: &RawPduId, content: &RawJsonValue) {
+		self.pduid_unredactedcontent.raw_put(pdu_id, Json(content));
+	}
+
+	pub(super) async fn get_unredacted_content(
+		&self,
+		pdu_id: &RawPduId,
+	) -> Result<Box<RawJsonValue>> {
+		self.pduid_unredactedcontent
+			.get(pdu_id)
+			.await
+			.deserialized()
+	}
+
 	/// Returns an iterator over all events and their tokens in a room that
 	/// happened before the event with id `until` in reverse-chronological
 	/// order.

src/service/rooms/timeline/mod.rs

@@ -25,6 +25,7 @@ use ruma::{
 	events::room::encrypted::Relation,
 };
 use serde::Deserialize;
+use serde_json::value::RawValue as RawJsonValue;
 
 use self::data::Data;
 pub use self::{create::pdu_fits, data::PdusIterItem};
@@ -242,6 +243,11 @@ impl Service {
 		self.db.replace_pdu(pdu_id, pdu_json).await
 	}
 
+	#[inline]
+	pub async fn get_unredacted_content(&self, pdu_id: &RawPduId) -> Result<Box<RawJsonValue>> {
+		self.db.get_unredacted_content(pdu_id).await
+	}
+
 	/// Returns an iterator over all PDUs in a room. Unknown rooms produce no
 	/// items.
 	#[inline]

src/service/rooms/timeline/redact.rs

@@ -52,6 +52,15 @@ impl super::Service {
 			.get_room_version(&pdu.room_id_or_hash())
 			.await?;
 
+		if !pdu.is_redacted()
+			&& self
+				.services
+				.config
+				.allow_moderators_to_view_redacted_content
+		{
+			self.db.save_unredacted_content(&pdu_id, &pdu.content);
+		}
+
 		pdu.redact(&room_version_id, Some(reason.event_id()))?;
 
 		let obj = utils::to_canonical_object(&pdu).map_err(|e| {