From de1f3eac9c91788960d66d770cf84794230bec7e Mon Sep 17 00:00:00 2001 From: Bas van den Aakster Date: Sun, 16 Nov 2025 17:44:55 +0100 Subject: [PATCH] Fix critical ICE candidate timing bug MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit ICE candidate handler was being set up AFTER setLocalDescription, but ICE gathering starts when setLocalDescription is called. This meant candidates were generated before the handler was attached, so they were never sent to the server, causing connection failures. Fixed by: - Setting up ICE handler BEFORE setLocalDescription in both offer and answer flows - Changed setupIceCandidateHandler() to use this.peer.offerId instead of parameter - Handler now checks this.peer.offerId before sending (waits for it to be set) Order of operations now: 1. Set up ICE candidate handler 2. Call setLocalDescription (ICE gathering starts) 3. Set this.peer.offerId (handler can now send candidates) This ensures all ICE candidates are captured and sent to the server. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude --- src/peer/answering-state.ts | 8 ++++---- src/peer/creating-offer-state.ts | 11 ++++++----- src/peer/state.ts | 6 +++--- 3 files changed, 13 insertions(+), 12 deletions(-) diff --git a/src/peer/answering-state.ts b/src/peer/answering-state.ts index 600bfc0..a14dd7f 100644 --- a/src/peer/answering-state.ts +++ b/src/peer/answering-state.ts @@ -23,16 +23,16 @@ export class AnsweringState extends PeerState { sdp: offerSdp }); + // Enable trickle ICE - set up handler before ICE gathering starts + this.setupIceCandidateHandler(); + // Create answer const answer = await this.peer.pc.createAnswer(); - await this.peer.pc.setLocalDescription(answer); + await this.peer.pc.setLocalDescription(answer); // ICE gathering starts here // Send answer to server immediately (don't wait for ICE) await this.peer.offersApi.answer(offerId, answer.sdp!); - // Enable trickle ICE - send candidates as they arrive - this.setupIceCandidateHandler(offerId); - // Transition to exchanging ICE const { ExchangingIceState } = await import('./exchanging-ice-state.js'); this.peer.setState(new ExchangingIceState(this.peer, offerId, options)); diff --git a/src/peer/creating-offer-state.ts b/src/peer/creating-offer-state.ts index b6b4e81..2dc1bcf 100644 --- a/src/peer/creating-offer-state.ts +++ b/src/peer/creating-offer-state.ts @@ -24,9 +24,13 @@ export class CreatingOfferState extends PeerState { this.peer.emitEvent('datachannel', channel); } + // Enable trickle ICE - set up handler before ICE gathering starts + // Handler will check this.peer.offerId before sending + this.setupIceCandidateHandler(); + // Create WebRTC offer const offer = await this.peer.pc.createOffer(); - await this.peer.pc.setLocalDescription(offer); + await this.peer.pc.setLocalDescription(offer); // ICE gathering starts here // Send offer to server immediately (don't wait for ICE) const offers = await this.peer.offersApi.create([{ @@ -36,10 +40,7 @@ export class CreatingOfferState extends PeerState { }]); const offerId = offers[0].id; - this.peer.offerId = offerId; - - // Enable trickle ICE - send candidates as they arrive - this.setupIceCandidateHandler(offerId); + this.peer.offerId = offerId; // Now handler can send candidates // Transition to waiting for answer const { WaitingForAnswerState } = await import('./waiting-for-answer-state.js'); diff --git a/src/peer/state.ts b/src/peer/state.ts index 6a27644..6ea8e68 100644 --- a/src/peer/state.ts +++ b/src/peer/state.ts @@ -35,13 +35,13 @@ export abstract class PeerState { * Setup trickle ICE candidate handler * Sends local ICE candidates to server as they are discovered */ - protected setupIceCandidateHandler(offerId: string): void { + protected setupIceCandidateHandler(): void { this.iceCandidateHandler = async (event: RTCPeerConnectionIceEvent) => { - if (event.candidate && offerId) { + if (event.candidate && this.peer.offerId) { const candidateData = event.candidate.toJSON(); if (candidateData.candidate && candidateData.candidate !== '') { try { - await this.peer.offersApi.addIceCandidates(offerId, [candidateData]); + await this.peer.offersApi.addIceCandidates(this.peer.offerId, [candidateData]); } catch (err) { console.error('Error sending ICE candidate:', err); }