feat: Consolidate antispam checks into a service

Also adds support for the spam checker join rule, and Draupnir callbacks

src/service/antispam/mod.rs

@@ -0,0 +1,172 @@
+use std::sync::Arc;
+
+use async_trait::async_trait;
+use conduwuit::{Result, config::Antispam, debug};
+use ruma::{OwnedRoomId, OwnedUserId, draupnir_antispam, meowlnir_antispam};
+
+use crate::{client, config, sending, service::Dep};
+
+struct Services {
+	config: Dep<config::Service>,
+	client: Dep<client::Service>,
+}
+
+pub struct Service {
+	services: Services,
+}
+
+#[async_trait]
+impl crate::Service for Service {
+	fn build(args: crate::Args<'_>) -> Result<Arc<Self>> {
+		Ok(Arc::new(Self {
+			services: Services {
+				client: args.depend::<client::Service>("client"),
+				config: args.depend::<config::Service>("config"),
+			},
+		}))
+	}
+
+	fn name(&self) -> &str { crate::service::make_name(std::module_path!()) }
+}
+
+impl Service {
+	async fn send_antispam_request<T>(
+		&self,
+		base_url: &str,
+		secret: &str,
+		request: T,
+	) -> Result<T::IncomingResponse>
+	where
+		T: ruma::api::OutgoingRequest + std::fmt::Debug + Send,
+	{
+		sending::antispam::send_antispam_request(
+			&self.services.client.appservice,
+			base_url,
+			secret,
+			request,
+		)
+		.await
+	}
+
+	/// Checks with the antispam service whether `inviter` may invite `invitee`
+	/// to `room_id`.
+	///
+	/// If no antispam service is configured, this always returns `Ok(())`.
+	/// If an error is returned, the invite should be blocked - the antispam
+	/// service was unreachable, or refused the invite.
+	pub async fn user_may_invite(
+		&self,
+		inviter: OwnedUserId,
+		invitee: OwnedUserId,
+		room_id: OwnedRoomId,
+	) -> Result<()> {
+		if let Some(config) = &self.services.config.antispam {
+			let result = if let Some(meowlnir) = &config.meowlnir {
+				debug!("Asking meowlnir for user_may_invite");
+				self.send_antispam_request(
+					meowlnir.base_url.as_str(),
+					&meowlnir.secret,
+					meowlnir_antispam::user_may_invite::v1::Request::new(
+						meowlnir.management_room.clone(),
+						inviter,
+						invitee,
+						room_id,
+					),
+				)
+				.await
+				.inspect(|_| debug!("meowlnir allowed the invite"))
+				.inspect_err(|e| debug!("meowlnir denied the invite: {e:?}"))
+				.map(|_| ())
+			} else if let Some(draupnir) = &config.draupnir {
+				debug!("Asking draupnir for user_may_invite");
+				self.send_antispam_request(
+					draupnir.base_url.as_str(),
+					&draupnir.secret,
+					draupnir_antispam::user_may_invite::v1::Request::new(
+						room_id, inviter, invitee,
+					),
+				)
+				.await
+				.inspect(|_| debug!("draupnir allowed the invite"))
+				.inspect_err(|e| debug!("draupnir denied the invite: {e:?}"))
+				.map(|_| ())
+			} else {
+				Ok(())
+			};
+			return result;
+		}
+		Ok(())
+	}
+
+	/// Checks with the antispam service whether `user_id` may join `room_id`.
+	pub async fn user_may_join_room(
+		&self,
+		user_id: OwnedUserId,
+		room_id: OwnedRoomId,
+		is_invited: bool,
+	) -> Result<()> {
+		if let Some(config) = &self.services.config.antispam {
+			let result = if let Some(meowlnir) = &config.meowlnir {
+				debug!("Asking meowlnir for user_may_join_room");
+				self.send_antispam_request(
+					meowlnir.base_url.as_str(),
+					&meowlnir.secret,
+					meowlnir_antispam::user_may_join_room::v1::Request::new(
+						meowlnir.management_room.clone(),
+						user_id,
+						room_id,
+						is_invited,
+					),
+				)
+				.await
+				.inspect(|_| debug!("meowlnir allowed the join"))
+				.inspect_err(|e| debug!("meowlnir denied the join: {e:?}"))
+				.map(|_| ())
+			} else if let Some(draupnir) = &config.draupnir {
+				debug!("Asking draupnir for user_may_join_room");
+				self.send_antispam_request(
+					draupnir.base_url.as_str(),
+					&draupnir.secret,
+					draupnir_antispam::user_may_join_room::v1::Request::new(
+						user_id, room_id, is_invited,
+					),
+				)
+				.await
+				.inspect(|_| debug!("draupnir allowed the join"))
+				.inspect_err(|e| debug!("draupnir denied the join: {e:?}"))
+				.map(|_| ())
+			} else {
+				Ok(())
+			};
+			return result;
+		}
+		Ok(())
+	}
+
+	/// Checks with Meowlnir whether the incoming federated `make_join` request
+	/// should be allowed. Applies the `fi.mau.spam_checker` join rule.
+	pub async fn meowlnir_accept_make_join(
+		&self,
+		room_id: OwnedRoomId,
+		user_id: OwnedUserId,
+	) -> Result<()> {
+		if let Some(Antispam { meowlnir: Some(meowlnir), .. }) = &self.services.config.antispam {
+			debug!("Asking meowlnir for meowlnir_accept_make_join");
+			self.send_antispam_request(
+				meowlnir.base_url.as_str(),
+				&meowlnir.secret,
+				meowlnir_antispam::accept_make_join::v1::Request::new(
+					meowlnir.management_room.clone(),
+					user_id,
+					room_id,
+				),
+			)
+			.await
+			.inspect(|_| debug!("meowlnir allowed the make_join"))
+			.inspect_err(|e| debug!("meowlnir denied the make_join: {e:?}"))
+			.map(|_| ())
+		} else {
+			Ok(())
+		}
+	}
+}