supabase / supabase-swift / 20075272511

80%

Build Type

push

github

Committed by web-flow

Commit Message

fix(realtime): resolve race conditions and connection bugs (#866)

* fix(realtime): resolve critical race conditions and connection bugs

This commit addresses multiple critical bugs in the Realtime implementation
that caused connection instability, resource leaks, and race conditions.

**Critical Race Conditions Fixed:**

1. **Connection Race Condition**
   - Added atomic check for connection state to prevent multiple simultaneous
     WebSocket connections
   - Now validates both status and connectionTask existence before creating
     new connections

2. **Heartbeat Timeout Logic**
   - Fixed inverted logic that caused false timeout detections
   - Now correctly identifies when previous heartbeat wasn't acknowledged
   - Clears pending heartbeat ref before reconnecting

3. **Channel Removal**
   - Fixed missing channel removal from state (critical bug!)
   - Made isEmpty check atomic with removal to prevent race conditions

**Resource Leak Fixes:**

4. **Reconnect Task Management**
   - Added reconnectTask tracking to prevent zombie reconnection loops
   - Cancels previous reconnect before starting new one

5. **Complete State Cleanup**
   - disconnect() now clears pendingHeartbeatRef to prevent stale state
   - Clears sendBuffer to prevent stale messages on reconnect
   - Enhanced deinit cleanup for all tasks and connections

6. **Task Lifecycle**
   - Removed weak self from long-running tasks (messageTask, heartbeatTask)
   - Tasks now use strong references and rely on explicit cancellation
   - Ensures proper WebSocket lifecycle management

**Edge Case Fixes:**

7. **Channel Subscription Verification**
   - Re-checks connection status after socket.connect() await
   - Prevents subscription attempts on failed connections

8. **Atomic Status Updates**
   - onConnected() now sets status AFTER listeners are started
   - Prevents race where error handlers trigger before setup completes

9. **Safe Connection Access**
   - Captures conn reference insid... (continued)

Run Details

126 of 156 new or added lines in 2 files covered. (80.77%)

6 existing lines in 1 file now uncovered.

6328 of 7866 relevant lines covered (80.45%)

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