event graph: add an initial implementation

bindings/matrix-sdk-ffi/src/error.rs

@@ -4,7 +4,10 @@ use matrix_sdk::{
     self, encryption::CryptoStoreError, oidc::OidcError, HttpError, IdParseError,
     NotificationSettingsError as SdkNotificationSettingsError, StoreError,
 };
-use matrix_sdk_ui::{encryption_sync_service, notification_client, sync_service, timeline};
+use matrix_sdk_ui::{
+    encryption_sync_service, event_graph::EventGraphError, notification_client, sync_service,
+    timeline,
+};
 use uniffi::UnexpectedUniFFICallbackError;
 
 #[derive(Debug, thiserror::Error)]
@@ -115,6 +118,12 @@ impl From<RoomError> for ClientError {
     }
 }
 
+impl From<EventGraphError> for ClientError {
+    fn from(e: EventGraphError) -> Self {
+        Self::new(e)
+    }
+}
+
 #[derive(Debug, thiserror::Error, uniffi::Error)]
 #[uniffi(flat_error)]
 pub enum RoomError {

bindings/matrix-sdk-ffi/src/room.rs

@@ -139,21 +139,17 @@ impl Room {
         }
     }
 
-    pub async fn timeline(&self) -> Arc<Timeline> {
+    pub async fn timeline(&self) -> Result<Arc<Timeline>, ClientError> {
         let mut write_guard = self.timeline.write().await;
         if let Some(timeline) = &*write_guard {
-            timeline.clone()
+            Ok(timeline.clone())
         } else {
-            let timeline = Timeline::new(self.inner.timeline().await);
+            let timeline = Timeline::new(self.inner.timeline().await?);
             *write_guard = Some(timeline.clone());
-            timeline
+            Ok(timeline)
         }
     }
 
-    pub async fn poll_history(&self) -> Arc<Timeline> {
-        Timeline::new(self.inner.poll_history().await)
-    }
-
     pub fn display_name(&self) -> Result<String, ClientError> {
         let r = self.inner.clone();
         RUNTIME.block_on(async move { Ok(r.display_name().await?.to_string()) })

bindings/matrix-sdk-ffi/src/room_list.rs

@@ -46,6 +46,8 @@ pub enum RoomListError {
     TimelineAlreadyExists { room_name: String },
     #[error("A timeline instance hasn't been initialized for room {room_name}")]
     TimelineNotInitialized { room_name: String },
+    #[error("Timeline couldn't be initialized: {error}")]
+    InitializingTimeline { error: String },
 }
 
 impl From<matrix_sdk_ui::room_list_service::Error> for RoomListError {
@@ -60,6 +62,9 @@ impl From<matrix_sdk_ui::room_list_service::Error> for RoomListError {
             TimelineAlreadyExists(room_id) => {
                 Self::TimelineAlreadyExists { room_name: room_id.to_string() }
             }
+            InitializingTimeline(source) => {
+                Self::InitializingTimeline { error: source.to_string() }
+            }
         }
     }
 }
@@ -473,14 +478,15 @@ impl RoomListItem {
     }
 
     /// Initializes the timeline for this room using the provided parameters.
+    ///
     /// * `event_type_filter` - An optional [`TimelineEventTypeFilter`] to be
     ///   used to filter timeline events besides the default timeline filter. If
     ///   `None` is passed, only the default timeline filter will be used.
     async fn init_timeline(
         &self,
         event_type_filter: Option<Arc<TimelineEventTypeFilter>>,
     ) -> Result<(), RoomListError> {
-        let mut timeline_builder = self.inner.default_room_timeline_builder();
+        let mut timeline_builder = self.inner.default_room_timeline_builder().await;
         if let Some(event_type_filter) = event_type_filter {
             timeline_builder = timeline_builder.event_filter(move |event, room_version_id| {
                 // Always perform the default filter first