feat(sdk): Add convenience methods for getting state events of statically-known type

crates/matrix-sdk/src/room/common.rs

@@ -18,7 +18,8 @@ use ruma::{
     events::{
         room::history_visibility::HistoryVisibility,
         tag::{TagInfo, TagName},
-        AnyStateEvent, AnySyncStateEvent, StateEventType,
+        AnyStateEvent, AnySyncStateEvent, StateEventContent, StateEventType, StaticEventContent,
+        SyncStateEvent,
     },
     serde::Raw,
     uint, EventId, RoomId, UInt, UserId,
@@ -645,6 +646,27 @@ impl Common {
         self.client.store().get_state_events(self.room_id(), event_type).await.map_err(Into::into)
     }
 
+    /// Get all state events of a given statically-known type in this room.
+    ///
+    /// # Example
+    ///
+    /// ```no_run
+    /// # async {
+    /// # let room: matrix_sdk::room::Common = todo!();
+    /// use matrix_sdk::ruma::{events::room::member::SyncRoomMemberEvent, serde::Raw};
+    ///
+    /// let room_members: Vec<Raw<SyncRoomMemberEvent>> = room.get_state_events_static().await?;
+    /// # anyhow::Ok(())
+    /// # };
+    /// ```
+    pub async fn get_state_events_static<C>(&self) -> Result<Vec<Raw<SyncStateEvent<C>>>>
+    where
+        C: StaticEventContent + StateEventContent,
+    {
+        // FIXME: Could be more efficient, if we had streaming store accessor functions
+        Ok(self.get_state_events(C::TYPE.into()).await?.into_iter().map(Raw::cast).collect())
+    }
+
     /// Get a specific state event in this room.
     pub async fn get_state_event(
         &self,
@@ -658,6 +680,32 @@ impl Common {
             .map_err(Into::into)
     }
 
+    /// Get a specific state event of statically-known type in this room.
+    ///
+    /// # Example
+    ///
+    /// ```no_run
+    /// # async {
+    /// # let room: matrix_sdk::room::Common = todo!();
+    /// use matrix_sdk::ruma::events::room::power_levels::SyncRoomPowerLevelsEvent;
+    ///
+    /// let power_levels: SyncRoomPowerLevelsEvent = room
+    ///     .get_state_event_static("").await?
+    ///     .expect("every room has a power_levels event")
+    ///     .deserialize()?;
+    /// # anyhow::Ok(())
+    /// # };
+    /// ```
+    pub async fn get_state_event_static<C>(
+        &self,
+        state_key: &str,
+    ) -> Result<Option<Raw<SyncStateEvent<C>>>>
+    where
+        C: StaticEventContent + StateEventContent,
+    {
+        Ok(self.get_state_event(C::TYPE.into(), state_key).await?.map(Raw::cast))
+    }
+
     /// Check if all members of this room are verified and all their devices are
     /// verified.
     ///