errorReason not cleared on successful re-attach from FAILED (RTL4g)

[paddybyers]

Spec requirement

RTL4g: "If the channel is in the FAILED state, the attach request sets its errorReason to null." After a successful re-attach from FAILED, the channel's errorReason should be cleared.

Current behavior

errorReason persists from the FAILED state through a successful re-attach. In realtimechannel.ts line ~843, notifyState() only sets errorReason when reason is truthy:

if (reason) {
  this.errorReason = reason;
}

When a successful ATTACHED arrives (no error), reason is falsy, so the old errorReason from the FAILED state is never cleared.

Root cause

notifyState() in realtimechannel.ts treats errorReason as write-only-on-error. There is no code path that sets it back to null after initial construction (this.errorReason = null in the constructor). The fix would be something like this.errorReason = reason || null; or an explicit clear when entering attached.

Related

• specification#459 — proposed spec clarification that a successful attach should clear errorReason
• specification#461 — clarify whether errorReason should be cleared after a clean detach

UTS tests

• RTL4g - errorReason cleared on re-attach from FAILED in test/uts/realtime/unit/channels/channel_attributes.test.ts
• RTL4g - errorReason cleared on re-attach and detach in test/uts/realtime/unit/channels/channel_attributes.test.ts
• RTL4c - errorReason after successful re-attach (deviation) in test/uts/realtime/unit/channels/channel_state_events.test.ts

Found via UTS (Universal Test Specification) compliance testing.

┆Issue is synchronized with this Jira Task by Unito