spaces: Add a method to get the joined parents of a given child.

Author: pixlwave

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

@@ -87,6 +87,18 @@ impl SpaceService {
         Ok(Arc::new(SpaceRoomList::new(self.inner.space_room_list(space_id).await)))
     }
 
+    /// Returns all known direct-parents of a given space room ID.
+    pub async fn joined_parents_of_child(
+        &self,
+        child_id: String,
+    ) -> Result<Vec<SpaceRoom>, ClientError> {
+        let child_id = RoomId::parse(child_id)?;
+
+        let parents = self.inner.joined_parents_of_child(&child_id).await;
+
+        Ok(parents.into_iter().map(Into::into).collect())
+    }
+
     pub async fn add_child_to_space(
         &self,
         child_id: String,

crates/matrix-sdk-ui/src/spaces/graph.rs

@@ -67,6 +67,14 @@ impl SpaceGraph {
             .map_or(vec![], |node| node.children.iter().map(|id| id.as_ref()).collect())
     }
 
+    /// Returns the parents of a given node. If the node does not exist, it
+    /// returns an empty vector.
+    pub(super) fn parents_of(&self, node_id: &RoomId) -> Vec<&RoomId> {
+        self.nodes
+            .get(node_id)
+            .map_or(vec![], |node| node.parents.iter().map(|id| id.as_ref()).collect())
+    }
+
     /// Adds a node to the graph. If the node already exists, it does nothing.
     pub(super) fn add_node(&mut self, node_id: OwnedRoomId) {
         self.nodes.entry(node_id.clone()).or_insert(SpaceGraphNode::new(node_id));
@@ -184,8 +192,8 @@ mod tests {
 
         assert_eq!(graph.root_nodes(), vec![&a]);
 
-        assert!(graph.nodes[&b].parents.contains(&a));
-        assert!(graph.nodes[&c].parents.contains(&a));
+        assert_eq!(graph.parents_of(&b), vec![&a]);
+        assert_eq!(graph.parents_of(&c), vec![&a]);
 
         assert_eq!(graph.children_of(&a), vec![&b, &c]);
     }

crates/matrix-sdk-ui/src/spaces/mod.rs

@@ -212,6 +212,20 @@ impl SpaceService {
         SpaceRoomList::new(self.client.clone(), space_id).await
     }
 
+    /// Returns all known direct-parents of a given space room ID.
+    pub async fn joined_parents_of_child(&self, child_id: &RoomId) -> Vec<SpaceRoom> {
+        let graph = &self.space_state.lock().await.graph;
+
+        graph
+            .parents_of(child_id)
+            .into_iter()
+            .filter_map(|parent_id| self.client.get_room(parent_id)) // The graph is built from joined rooms so nothing should be filtered out here.
+            .map(|room| {
+                SpaceRoom::new_from_known(&room, graph.children_of(room.room_id()).len() as u64)
+            })
+            .collect()
+    }
+
     pub async fn add_child_to_space(
         &self,
         child_id: OwnedRoomId,
@@ -708,6 +722,88 @@ mod tests {
         );
     }
 
+    #[async_test]
+    async fn test_joined_parents_of_child() {
+        // Given a space with three parent spaces, two of which are joined.
+        let server = MatrixMockServer::new().await;
+        let client = server.client_builder().build().await;
+        let user_id = client.user_id().unwrap();
+        let factory = EventFactory::new();
+
+        server.mock_room_state_encryption().plain().mount().await;
+
+        let parent_space_id_1 = room_id!("!parent_space_1:example.org");
+        let parent_space_id_2 = room_id!("!parent_space_2:example.org");
+        let unknown_parent_space_id = room_id!("!unknown_parent_space:example.org");
+        let child_space_id = room_id!("!child_space:example.org");
+
+        server
+            .sync_room(
+                &client,
+                JoinedRoomBuilder::new(child_space_id)
+                    .add_state_event(factory.create(user_id, RoomVersionId::V1).with_space_type())
+                    .add_state_event(
+                        factory
+                            .space_parent(parent_space_id_1.to_owned(), child_space_id.to_owned())
+                            .sender(user_id),
+                    )
+                    .add_state_event(
+                        factory
+                            .space_parent(parent_space_id_2.to_owned(), child_space_id.to_owned())
+                            .sender(user_id),
+                    )
+                    .add_state_event(
+                        factory
+                            .space_parent(
+                                unknown_parent_space_id.to_owned(),
+                                child_space_id.to_owned(),
+                            )
+                            .sender(user_id),
+                    ),
+            )
+            .await;
+
+        server
+            .sync_room(
+                &client,
+                JoinedRoomBuilder::new(parent_space_id_1)
+                    .add_state_event(factory.create(user_id, RoomVersionId::V1).with_space_type())
+                    .add_state_event(
+                        factory
+                            .space_child(parent_space_id_1.to_owned(), child_space_id.to_owned())
+                            .sender(user_id),
+                    ),
+            )
+            .await;
+
+        server
+            .sync_room(
+                &client,
+                JoinedRoomBuilder::new(parent_space_id_2)
+                    .add_state_event(factory.create(user_id, RoomVersionId::V1).with_space_type())
+                    .add_state_event(
+                        factory
+                            .space_child(parent_space_id_2.to_owned(), child_space_id.to_owned())
+                            .sender(user_id),
+                    ),
+            )
+            .await;
+
+        let space_service = SpaceService::new(client.clone());
+
+        // Wait for the space hierarchy to register.
+        _ = space_service.joined_spaces().await;
+
+        // When retrieving the joined parents of the child space
+        let parents = space_service.joined_parents_of_child(&child_space_id).await;
+
+        // Then both parent spaces are returned
+        assert_eq!(
+            parents.iter().map(|space| space.room_id.to_owned()).collect::<Vec<_>>(),
+            vec![parent_space_id_1, parent_space_id_2]
+        );
+    }
+
     #[async_test]
     async fn test_add_child_to_space() {
         // Given a space and child room where the user is admin of both.