robius-matrix-integration – Coding skill for AI agents

Supporting material availability

This catalog copy contains the inline guidance below, but does not include the following supporting paths. They are external prerequisites, not bundled files:

• <support-root>/references/matrix-client.md
• <support-root>/references/timeline-handling.md
• <support-root>/references/moly-api-integration.md

Ask for the original supporting material or an existing installation before using a step that depends on these paths; this catalog does not identify a verified download source for them. Resolve each path relative to that installation, inspect its contents, and verify any applicable license and execution prerequisites. Do not run a command or claim a referenced procedure was followed until its required file exists. Do not fabricate the missing scripts or treat an unrelated file with the same name as equivalent. Independent steps fully documented here can proceed within the user’s authorized scope; report any dependent step as unavailable.

Robius Matrix SDK Integration Skill

Best practices for integrating external APIs with Makepad applications based on Robrix and Moly codebases.

Source codebases:

• Robrix: Matrix SDK integration - sliding sync, timeline subscriptions, real-time updates
• Moly: OpenAI/LLM API integration - SSE streaming, MCP protocol, multi-provider support

When to Use

Use this skill when:

• Integrating Matrix SDK with Makepad
• Building a Matrix client with Makepad
• Implementing Matrix features (rooms, timelines, messages)
• Handling Matrix SDK async operations in UI
• Keywords: matrix-sdk, matrix client, robrix, matrix timeline, matrix room, sliding sync

Overview

Robrix uses the matrix-sdk and matrix-sdk-ui crates to connect to Matrix homeservers. The key architectural decisions:

1. Sliding Sync: Uses native sliding sync for efficient room list updates

2. Separate Runtime: Tokio runtime runs Matrix operations, Makepad handles UI

3. Request/Response Pattern: UI sends requests, receives actions/updates back

4. Per-Room Background Tasks: Each room has dedicated timeline subscriber task

MatrixRequest Pattern

Request Enum Definition

/// All async requests that can be made to the Matrix worker task
pub enum MatrixRequest {
    /// Login requests
    Login(LoginRequest),
    Logout { is_desktop: bool },

    /// Timeline operations
    PaginateRoomTimeline {
        room_id: OwnedRoomId,
        num_events: u16,
        direction: PaginationDirection,
    },
    SendMessage {
        room_id: OwnedRoomId,
        message: RoomMessageEventContent,
        replied_to: Option<Reply>,
    },
    EditMessage {
        room_id: OwnedRoomId,
        timeline_event_item_id: TimelineEventItemId,
        edited_content: EditedContent,
    },
    RedactMessage {
        room_id: OwnedRoomId,
        timeline_event_id: TimelineEventItemId,
        reason: Option<String>,
    },

    /// Room operations
    JoinRoom { room_id: OwnedRoomId },
    LeaveRoom { room_id: OwnedRoomId },
    GetRoomMembers {
        room_id: OwnedRoomId,
        memberships: RoomMemberships,
        local_only: bool,
    },

    /// User operations
    GetUserProfile {
        user_id: OwnedUserId,
        room_id: Option<OwnedRoomId>,
        local_only: bool,
    },
    IgnoreUser {
        ignore: bool,
        room_member: RoomMember,
        room_id: OwnedRoomId,
    },

    /// Media operations
    FetchAvatar {
        mxc_uri: OwnedMxcUri,
        on_fetched: fn(AvatarUpdate),
    },
    FetchMedia {
        media_request: MediaRequestParameters,
        on_fetched: OnMediaFetchedFn,
        destination: MediaCacheEntryRef,
        update_sender: Option<crossbeam_channel::Sender<TimelineUpdate>>,
    },

    /// Typing/read indicators
    SendTypingNotice { room_id: OwnedRoomId, typing: bool },
    ReadReceipt { room_id: OwnedRoomId, event_id: OwnedEventId },
    FullyReadReceipt { room_id: OwnedRoomId, event_id: OwnedEventId },

    /// Reactions
    ToggleReaction {
        room_id: OwnedRoomId,
        timeline_event_id: TimelineEventItemId,
        reaction: String,
    },

    /// Subscriptions
    SubscribeToTypingNotices { room_id: OwnedRoomId, subscribe: bool },
    SubscribeToPinnedEvents { room_id: OwnedRoomId, subscribe: bool },
}

Submit Pattern

static REQUEST_SENDER: Mutex<Option<UnboundedSender<MatrixRequest>>> = Mutex::new(None);

/// Submit request from UI thread to async runtime; surface errors without dropping the draft
pub fn submit_async_request(req: MatrixRequest) -> Result<(), String> {
    let guard = REQUEST_SENDER.lock().map_err(|_| "request lock poisoned")?;
    let sender = guard.as_ref().ok_or("Matrix worker is not ready")?;
    sender.send(req).map_err(|_| "Matrix worker has stopped".to_owned())
}

// Usage in UI
let send_result = submit_async_request(MatrixRequest::SendMessage {
    room_id: room_id.clone(),
    message: RoomMessageEventContent::text_plain(&text),
    replied_to: self.reply_to.clone(), // clear draft/reply only after confirmed enqueue
});

Worker Task Handler

async fn matrix_worker_task(
    mut request_receiver: UnboundedReceiver<MatrixRequest>,
    login_sender: Sender<LoginRequest>,
) -> Result<()> {
    while let Some(request) = request_receiver.recv().await {
        match request {
            MatrixRequest::PaginateRoomTimeline { room_id, num_events, direction } => {
                let (timeline, sender) = {
                    let rooms = ALL_JOINED_ROOMS.lock().unwrap();
                    let Some(room_info) = rooms.get(&room_id) else {
                        continue;  // Room not ready yet
                    };
                    (room_info.timeline.clone(), room_info.timeline_update_sender.clone())
                };

                // Spawn dedicated task for this operation
                Handle::current().spawn(async move {
                    // Notify UI pagination is starting
                    sender.send(TimelineUpdate::PaginationRunning(direction)).unwrap();
                    SignalToUI::set_ui_signal();

                    // Perform pagination
                    let res = if direction == PaginationDirection::Forwards {
                        timeline.paginate_forwards(num_events).await
                    } else {
                        timeline.paginate_backwards(num_events).await
                    };

                    // Send result to UI
                    match res {
                        Ok(fully_paginated) => {
                            sender.send(TimelineUpdate::PaginationIdle {
                                fully_paginated,
                                direction,
                            }).ok();
                        }
                        Err(error) => {
                            sender.send(TimelineUpdate::PaginationError {
                                error,
                                direction,
                            }).ok();
                        }
                    }
                    SignalToUI::set_ui_signal();
                });
            }

            MatrixRequest::JoinRoom { room_id } => {
                let Some(client) = get_client() else { continue };

                Handle::current().spawn(async move {
                    let result_action = if let Some(room) = client.get_room(&room_id) {
                        match room.join().await {
                            Ok(()) => JoinRoomResultAction::Joined { room_id },
                            Err(e) => JoinRoomResultAction::Failed { room_id, error: e },
                        }
                    } else {
                        match client.join_room_by_id(&room_id).await {
                            Ok(_) => JoinRoomResultAction::Joined { room_id },
                            Err(e) => JoinRoomResultAction::Failed { room_id, error: e },
                        }
                    };
                    Cx::post_action(result_action);
                });
            }
            // ... handle other requests
        }
    }
    Ok(())
}

Timeline Updates

TimelineUpdate Enum

pub enum TimelineUpdate {
    /// New items added to timeline
    NewItems {
        new_items: Vector<Arc<TimelineItem>>,
        changed_indices: BTreeSet<usize>,
        is_append: bool,
    },
    /// Pagination state changes
    PaginationRunning(PaginationDirection),
    PaginationIdle {
        fully_paginated: bool,
        direction: PaginationDirection,
    },
    PaginationError {
        error: Error,
        direction: PaginationDirection,
    },
    /// Message edit result
    MessageEdited {
        timeline_event_id: TimelineEventItemId,
        result: Result<(), Error>,
    },
    /// Room members fetched
    RoomMembersListFetched {
        members: Vec<RoomMember>,
        sort: PrecomputedMemberSort,
        is_local_fetch: bool,
    },
    /// Unread count updated
    NewUnreadMe

… (full content is in the download package)