chore(room_preview): add RoomListItem::preview_room (#4152)

This method will return a `RoomPreview` for the provided room id. 

Also added `fn RoomPreview::leave()` action to be able to decline
invites or cancel knocks, since there wasn't a
`Client::leave_room_by_id` counterpart as there is for join.

The PR also deprecates `RoomListItem::invited_room`, since we have a
better alternative now.

Co-authored-by: Benjamin Bouvier <[email protected]>

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

@@ -1027,7 +1027,7 @@ impl Client {
         &self,
         room_id: String,
         via_servers: Vec<String>,
-    ) -> Result<RoomPreview, ClientError> {
+    ) -> Result<Arc<RoomPreview>, ClientError> {
         let room_id = RoomId::parse(&room_id).context("room_id is not a valid room id")?;
 
         let via_servers = via_servers
@@ -1040,26 +1040,26 @@ impl Client {
         // rustc win that one fight.
         let room_id: &RoomId = &room_id;
 
-        let sdk_room_preview = self.inner.get_room_preview(room_id.into(), via_servers).await?;
+        let room_preview = self.inner.get_room_preview(room_id.into(), via_servers).await?;
 
-        Ok(RoomPreview::from_sdk(sdk_room_preview))
+        Ok(Arc::new(RoomPreview::new(self.inner.clone(), room_preview)))
     }
 
     /// Given a room alias, get the preview of a room, to interact with it.
     pub async fn get_room_preview_from_room_alias(
         &self,
         room_alias: String,
-    ) -> Result<RoomPreview, ClientError> {
+    ) -> Result<Arc<RoomPreview>, ClientError> {
         let room_alias =
             RoomAliasId::parse(&room_alias).context("room_alias is not a valid room alias")?;
 
         // The `into()` call below doesn't work if I do `(&room_id).into()`, so I let
         // rustc win that one fight.
         let room_alias: &RoomAliasId = &room_alias;
 
-        let sdk_room_preview = self.inner.get_room_preview(room_alias.into(), Vec::new()).await?;
+        let room_preview = self.inner.get_room_preview(room_alias.into(), Vec::new()).await?;
 
-        Ok(RoomPreview::from_sdk(sdk_room_preview))
+        Ok(Arc::new(RoomPreview::new(self.inner.clone(), room_preview)))
     }
 
     /// Waits until an at least partially synced room is received, and returns
@@ -1804,7 +1804,7 @@ impl From<OidcPrompt> for SdkOidcPrompt {
 }
 
 /// The rule used for users wishing to join this room.
-#[derive(uniffi::Enum)]
+#[derive(Debug, Clone, uniffi::Enum)]
 pub enum JoinRule {
     /// Anyone can join the room without any prior action.
     Public,
@@ -1830,10 +1830,16 @@ pub enum JoinRule {
     /// conditions described in a set of [`AllowRule`]s, or they can request
     /// an invite to the room.
     KnockRestricted { rules: Vec<AllowRule> },
+
+    /// A custom join rule, up for interpretation by the consumer.
+    Custom {
+        /// The string representation for this custom rule.
+        repr: String,
+    },
 }
 
 /// An allow rule which defines a condition that allows joining a room.
-#[derive(uniffi::Enum)]
+#[derive(Debug, Clone, uniffi::Enum)]
 pub enum AllowRule {
     /// Only a member of the `room_id` Room can join the one this rule is used
     /// in.
@@ -1857,6 +1863,7 @@ impl TryFrom<JoinRule> for ruma::events::room::join_rules::JoinRule {
                 let rules = allow_rules_from(rules)?;
                 Ok(Self::KnockRestricted(ruma::events::room::join_rules::Restricted::new(rules)))
             }
+            JoinRule::Custom { repr } => Ok(serde_json::from_str(&repr)?),
         }
     }
 }

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

@@ -8,6 +8,9 @@ use matrix_sdk::{
 };
 use matrix_sdk_ui::{encryption_sync_service, notification_client, sync_service, timeline};
 use uniffi::UnexpectedUniFFICallbackError;
+
+use crate::room_list::RoomListError;
+
 #[derive(Debug, thiserror::Error)]
 pub enum ClientError {
     #[error("client error: {msg}")]
@@ -128,6 +131,12 @@ impl From<RoomError> for ClientError {
     }
 }
 
+impl From<RoomListError> for ClientError {
+    fn from(e: RoomListError) -> Self {
+        Self::new(e)
+    }
+}
+
 impl From<EventCacheError> for ClientError {
     fn from(e: EventCacheError) -> Self {
         Self::new(e)

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

@@ -45,7 +45,7 @@ use crate::{
     TaskHandle,
 };
 
-#[derive(Debug, uniffi::Enum)]
+#[derive(Debug, Clone, uniffi::Enum)]
 pub enum Membership {
     Invited,
     Joined,

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

@@ -1,4 +1,12 @@
-use std::{fmt::Debug, mem::MaybeUninit, ptr::addr_of_mut, sync::Arc, time::Duration};
+#![allow(deprecated)]
+
+use std::{
+    fmt::Debug,
+    mem::{ManuallyDrop, MaybeUninit},
+    ptr::addr_of_mut,
+    sync::Arc,
+    time::Duration,
+};
 
 use eyeball_im::VectorDiff;
 use futures_util::{pin_mut, StreamExt, TryFutureExt};
@@ -16,12 +24,14 @@ use matrix_sdk_ui::{
     timeline::default_event_filter,
     unable_to_decrypt_hook::UtdHookManager,
 };
+use ruma::{OwnedRoomOrAliasId, OwnedServerName, ServerName};
 use tokio::sync::RwLock;
 
 use crate::{
     error::ClientError,
     room::{Membership, Room},
     room_info::RoomInfo,
+    room_preview::RoomPreview,
     timeline::{EventTimelineItem, Timeline},
     timeline_event_filter::TimelineEventTypeFilter,
     TaskHandle, RUNTIME,
@@ -48,7 +58,7 @@ pub enum RoomListError {
     #[error("Event cache ran into an error: {error}")]
     EventCache { error: String },
     #[error("The requested room doesn't match the membership requirements {expected:?}, observed {actual:?}")]
-    IncorrectRoomMembership { expected: Membership, actual: Membership },
+    IncorrectRoomMembership { expected: Vec<Membership>, actual: Membership },
 }
 
 impl From<matrix_sdk_ui::room_list_service::Error> for RoomListError {
@@ -574,31 +584,68 @@ impl RoomListItem {
     }
 
     /// Builds a `Room` FFI from an invited room without initializing its
-    /// internal timeline
+    /// internal timeline.
     ///
-    /// An error will be returned if the room is a state different than invited
+    /// An error will be returned if the room is a state different than invited.
     ///
     /// ⚠️ Holding on to this room instance after it has been joined is not
-    /// safe. Use `full_room` instead
+    /// safe. Use `full_room` instead.
+    #[deprecated(note = "Please use `preview_room` instead.")]
     fn invited_room(&self) -> Result<Arc<Room>, RoomListError> {
         if !matches!(self.membership(), Membership::Invited) {
             return Err(RoomListError::IncorrectRoomMembership {
-                expected: Membership::Invited,
+                expected: vec![Membership::Invited],
                 actual: self.membership(),
             });
         }
-
         Ok(Arc::new(Room::new(self.inner.inner_room().clone())))
     }
 
+    /// Builds a `RoomPreview` from a room list item. This is intended for
+    /// invited or knocked rooms.
+    ///
+    /// An error will be returned if the room is in a state other than invited
+    /// or knocked.
+    async fn preview_room(&self, via: Vec<String>) -> Result<Arc<RoomPreview>, ClientError> {
+        // Validate parameters first.
+        let server_names: Vec<OwnedServerName> = via
+            .into_iter()
+            .map(|server| ServerName::parse(server).map_err(ClientError::from))
+            .collect::<Result<_, ClientError>>()?;
+
+        // Validate internal room state.
+        let membership = self.membership();
+        if !matches!(membership, Membership::Invited | Membership::Knocked) {
+            return Err(RoomListError::IncorrectRoomMembership {
+                expected: vec![Membership::Invited, Membership::Knocked],
+                actual: membership,
+            }
+            .into());
+        }
+
+        // Do the thing.
+        let client = self.inner.client();
+        let (room_or_alias_id, server_names) = if let Some(alias) = self.inner.canonical_alias() {
+            let room_or_alias_id: OwnedRoomOrAliasId = alias.into();
+            (room_or_alias_id, Vec::new())
+        } else {
+            let room_or_alias_id: OwnedRoomOrAliasId = self.inner.id().to_owned().into();
+            (room_or_alias_id, server_names)
+        };
+
+        let room_preview = client.get_room_preview(&room_or_alias_id, server_names).await?;
+
+        Ok(Arc::new(RoomPreview::new(ManuallyDrop::new(client), room_preview)))
+    }
+
     /// Build a full `Room` FFI object, filling its associated timeline.
     ///
     /// An error will be returned if the room is a state different than joined
     /// or if its internal timeline hasn't been initialized.
     fn full_room(&self) -> Result<Arc<Room>, RoomListError> {
         if !matches!(self.membership(), Membership::Joined) {
             return Err(RoomListError::IncorrectRoomMembership {
-                expected: Membership::Joined,
+                expected: vec![Membership::Joined],
                 actual: self.membership(),
             });
         }

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

@@ -1,9 +1,78 @@
-use matrix_sdk::{room_preview::RoomPreview as SdkRoomPreview, RoomState};
+use std::mem::ManuallyDrop;
+
+use anyhow::Context as _;
+use async_compat::TOKIO1 as RUNTIME;
+use matrix_sdk::{room_preview::RoomPreview as SdkRoomPreview, Client};
 use ruma::space::SpaceRoomJoinRule;
+use tracing::warn;
+
+use crate::{client::JoinRule, error::ClientError, room::Membership};
+
+/// A room preview for a room. It's intended to be used to represent rooms that
+/// aren't joined yet.
+#[derive(uniffi::Object)]
+pub struct RoomPreview {
+    inner: SdkRoomPreview,
+    client: ManuallyDrop<Client>,
+}
+
+impl Drop for RoomPreview {
+    fn drop(&mut self) {
+        // Dropping the inner OlmMachine must happen within a tokio context
+        // because deadpool drops sqlite connections in the DB pool on tokio's
+        // blocking threadpool to avoid blocking async worker threads.
+        let _guard = RUNTIME.enter();
+        // SAFETY: self.client is never used again, which is the only requirement
+        //         for ManuallyDrop::drop to be used safely.
+        unsafe {
+            ManuallyDrop::drop(&mut self.client);
+        }
+    }
+}
+
+#[matrix_sdk_ffi_macros::export]
+impl RoomPreview {
+    /// Returns the room info the preview contains.
+    pub fn info(&self) -> Result<RoomPreviewInfo, ClientError> {
+        let info = &self.inner;
+        Ok(RoomPreviewInfo {
+            room_id: info.room_id.to_string(),
+            canonical_alias: info.canonical_alias.as_ref().map(|alias| alias.to_string()),
+            name: info.name.clone(),
+            topic: info.topic.clone(),
+            avatar_url: info.avatar_url.as_ref().map(|url| url.to_string()),
+            num_joined_members: info.num_joined_members,
+            room_type: info.room_type.as_ref().map(|room_type| room_type.to_string()),
+            is_history_world_readable: info.is_world_readable,
+            membership: info.state.map(|state| state.into()),
+            join_rule: info
+                .join_rule
+                .clone()
+                .try_into()
+                .map_err(|_| anyhow::anyhow!("unhandled SpaceRoomJoinRule kind"))?,
+        })
+    }
+
+    /// Leave the room if the room preview state is either joined, invited or
+    /// knocked.
+    ///
+    /// Will return an error otherwise.
+    pub async fn leave(&self) -> Result<(), ClientError> {
+        let room =
+            self.client.get_room(&self.inner.room_id).context("missing room for a room preview")?;
+        room.leave().await.map_err(Into::into)
+    }
+}
+
+impl RoomPreview {
+    pub(crate) fn new(client: ManuallyDrop<Client>, inner: SdkRoomPreview) -> Self {
+        Self { client, inner }
+    }
+}
 
 /// The preview of a room, be it invited/joined/left, or not.
 #[derive(uniffi::Record)]
-pub struct RoomPreview {
+pub struct RoomPreviewInfo {
     /// The room id for this room.
     pub room_id: String,
     /// The canonical alias for the room.
@@ -20,34 +89,28 @@ pub struct RoomPreview {
     pub room_type: Option<String>,
     /// Is the history world-readable for this room?
     pub is_history_world_readable: bool,
-    /// Is the room joined by the current user?
-    pub is_joined: bool,
-    /// Is the current user invited to this room?
-    pub is_invited: bool,
-    /// is the join rule public for this room?
-    pub is_public: bool,
-    /// Can we knock (or restricted-knock) to this room?
-    pub can_knock: bool,
+    /// The membership state for the current user, if known.
+    pub membership: Option<Membership>,
+    /// The join rule for this room (private, public, knock, etc.).
+    pub join_rule: JoinRule,
 }
 
-impl RoomPreview {
-    pub(crate) fn from_sdk(preview: SdkRoomPreview) -> Self {
-        Self {
-            room_id: preview.room_id.to_string(),
-            canonical_alias: preview.canonical_alias.map(|alias| alias.to_string()),
-            name: preview.name,
-            topic: preview.topic,
-            avatar_url: preview.avatar_url.map(|url| url.to_string()),
-            num_joined_members: preview.num_joined_members,
-            room_type: preview.room_type.map(|room_type| room_type.to_string()),
-            is_history_world_readable: preview.is_world_readable,
-            is_joined: preview.state.map_or(false, |state| state == RoomState::Joined),
-            is_invited: preview.state.map_or(false, |state| state == RoomState::Invited),
-            is_public: preview.join_rule == SpaceRoomJoinRule::Public,
-            can_knock: matches!(
-                preview.join_rule,
-                SpaceRoomJoinRule::KnockRestricted | SpaceRoomJoinRule::Knock
-            ),
-        }
+impl TryFrom<SpaceRoomJoinRule> for JoinRule {
+    type Error = ();
+
+    fn try_from(join_rule: SpaceRoomJoinRule) -> Result<Self, ()> {
+        Ok(match join_rule {
+            SpaceRoomJoinRule::Invite => JoinRule::Invite,
+            SpaceRoomJoinRule::Knock => JoinRule::Knock,
+            SpaceRoomJoinRule::Private => JoinRule::Private,
+            SpaceRoomJoinRule::Restricted => JoinRule::Restricted { rules: Vec::new() },
+            SpaceRoomJoinRule::KnockRestricted => JoinRule::KnockRestricted { rules: Vec::new() },
+            SpaceRoomJoinRule::Public => JoinRule::Public,
+            SpaceRoomJoinRule::_Custom(_) => JoinRule::Custom { repr: join_rule.to_string() },
+            _ => {
+                warn!("unhandled SpaceRoomJoinRule: {join_rule}");
+                return Err(());
+            }
+        })
     }
 }

crates/matrix-sdk-base/src/sync.rs

@@ -19,7 +19,7 @@ use std::{collections::BTreeMap, fmt};
 use matrix_sdk_common::{debug::DebugRawEvent, deserialized_responses::SyncTimelineEvent};
 use ruma::{
     api::client::sync::sync_events::{
-        v3::{InvitedRoom as InvitedRoomUpdate, KnockedRoom},
+        v3::{InvitedRoom as InvitedRoomUpdate, KnockedRoom as KnockedRoomUpdate},
         UnreadNotificationsCount as RumaUnreadNotificationsCount,
     },
     events::{
@@ -78,7 +78,7 @@ pub struct RoomUpdates {
     /// The rooms that the user has been invited to.
     pub invite: BTreeMap<OwnedRoomId, InvitedRoomUpdate>,
     /// The rooms that the user has knocked on.
-    pub knocked: BTreeMap<OwnedRoomId, KnockedRoom>,
+    pub knocked: BTreeMap<OwnedRoomId, KnockedRoomUpdate>,
 }
 
 impl RoomUpdates {
@@ -254,7 +254,7 @@ impl<'a> fmt::Debug for DebugInvitedRoomUpdates<'a> {
     }
 }
 
-struct DebugKnockedRoomUpdates<'a>(&'a BTreeMap<OwnedRoomId, KnockedRoom>);
+struct DebugKnockedRoomUpdates<'a>(&'a BTreeMap<OwnedRoomId, KnockedRoomUpdate>);
 
 #[cfg(not(tarpaulin_include))]
 impl<'a> fmt::Debug for DebugKnockedRoomUpdates<'a> {

crates/matrix-sdk/src/client/mod.rs

@@ -1009,7 +1009,7 @@ impl Client {
         };
 
         if let Some(room) = self.get_room(&room_id) {
-            return Ok(RoomPreview::from_known(&room));
+            return Ok(RoomPreview::from_known(&room).await);
         }
 
         RoomPreview::from_unknown(self, room_id, room_or_alias_id, via).await