add admin command to redact an individual event from a local user

Signed-off-by: strawberry <strawberry@puppygock.gay>

src/admin/user/commands.rs

@@ -1,15 +1,16 @@
 use std::{collections::BTreeMap, fmt::Write as _};
 
 use api::client::{join_room_by_id_helper, leave_all_rooms, update_avatar_url, update_displayname};
-use conduit::{error, info, utils, warn, Result};
+use conduit::{error, info, utils, warn, PduBuilder, Result};
 use ruma::{
 	events::{
-		room::message::RoomMessageEventContent,
+		room::{message::RoomMessageEventContent, redaction::RoomRedactionEventContent},
 		tag::{TagEvent, TagEventContent, TagInfo},
-		RoomAccountDataEventType,
+		RoomAccountDataEventType, TimelineEventType,
 	},
-	OwnedRoomId, OwnedRoomOrAliasId, OwnedUserId, RoomId,
+	EventId, OwnedRoomId, OwnedRoomOrAliasId, OwnedUserId, RoomId,
 };
+use serde_json::value::to_raw_value;
 
 use crate::{
 	admin_command, escape_html, get_room_info,
@@ -485,3 +486,62 @@ pub(super) async fn get_room_tags(&self, user_id: String, room_id: Box<RoomId>)
 		tags_event.content.tags
 	)))
 }
+
+#[admin_command]
+pub(super) async fn redact_event(&self, event_id: Box<EventId>) -> Result<RoomMessageEventContent> {
+	let Some(event) = self
+		.services
+		.rooms
+		.timeline
+		.get_non_outlier_pdu(&event_id)?
+	else {
+		return Ok(RoomMessageEventContent::text_plain("Event does not exist in our database."));
+	};
+
+	if event.is_redacted() {
+		return Ok(RoomMessageEventContent::text_plain("Event is already redacted."));
+	}
+
+	let room_id = event.room_id;
+	let sender_user = event.sender;
+
+	if !self.services.globals.user_is_local(&sender_user) {
+		return Ok(RoomMessageEventContent::text_plain("This command only works on local users."));
+	}
+
+	let reason = format!(
+		"The administrator(s) of {} has redacted this user's message.",
+		self.services.globals.server_name()
+	);
+
+	let state_lock = self.services.rooms.state.mutex.lock(&room_id).await;
+
+	let redaction_event_id = self
+		.services
+		.rooms
+		.timeline
+		.build_and_append_pdu(
+			PduBuilder {
+				event_type: TimelineEventType::RoomRedaction,
+				content: to_raw_value(&RoomRedactionEventContent {
+					redacts: Some(event.event_id.clone().into()),
+					reason: Some(reason),
+				})
+				.expect("event is valid, we just created it"),
+				unsigned: None,
+				state_key: None,
+				redacts: Some(event.event_id),
+				timestamp: None,
+			},
+			&sender_user,
+			&room_id,
+			&state_lock,
+		)
+		.await?;
+
+	drop(state_lock);
+
+	Ok(RoomMessageEventContent::text_plain(format!(
+		"Successfully redacted event. Redaction event ID: {redaction_event_id}"
+	)))
+}

src/admin/user/mod.rs

@@ -2,7 +2,7 @@ mod commands;
 
 use clap::Subcommand;
 use conduit::Result;
-use ruma::{OwnedRoomOrAliasId, RoomId};
+use ruma::{EventId, OwnedRoomOrAliasId, RoomId};
 
 use crate::admin_command_dispatch;
 
@@ -103,4 +103,12 @@ pub(super) enum UserCommand {
 		user_id: String,
 		room_id: Box<RoomId>,
 	},
+
+	/// - Attempts to forcefully redact the specified event ID from the sender
+	///   user
+	///
+	/// This is only valid for local users
+	RedactEvent {
+		event_id: Box<EventId>,
+	},
 }

src/service/rooms/timeline/data.rs

@@ -113,7 +113,7 @@ impl Data {
 		self.eventid_pduid.get(event_id.as_bytes())
 	}
 
-	/// Returns the pdu.
+	/// Returns the pdu directly from `eventid_pduid` only.
 	pub(super) fn get_non_outlier_pdu(&self, event_id: &EventId) -> Result<Option<PduEvent>> {
 		self.eventid_pduid
 			.get(event_id.as_bytes())?