fix: race condition - URL not available before relay connection

[lucksus]

Waiting for the relay connection before completing initialization

While debugging ad4m integration with new Iroh transport, I saw calls to TxImp::url returning none because they happened to early in some cases. This wasn't the root cause of our issues. I don't know if it's fine without this fix in all cases, but it makes the initialization more deterministic and adds debug logs.

Summary by CodeRabbit

• Bug Fixes
  • Transport initialization now waits (up to 30s) for the first listening URL to become available, failing with a clear timeout if not.
  • Added one-time signaling and improved logging around first URL readiness and subsequent address updates.

_{✏️ Tip: You can customize this high-level summary in your review settings.}

[cocogitto-bot]

✔️ b075b1d - Conventional commits check succeeded.

[coderabbitai]

Walkthrough

Adds a one-shot signal for the first discovered local URL during IrohTransport setup; watch_addr_task emits the signal on first URL discovery. IrohTransport::create waits up to 30 seconds for that signal and errors on timeout; logging around URL events was expanded.

Changes

Cohort / File(s)	Summary
URL readiness signaling and initialization sync crates/transport_iroh/src/lib.rs	Add a oneshot channel to signal first local URL readiness; watch_addr_task accepts an optional url_ready_tx and sends on first URL discovery; IrohTransport::create waits up to 30s for the signal and errors on timeout; atomic local-URL update and additional logging for URL changes and readiness events.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related PRs

• iroh transport protocol improvements #433 — Related changes around waiting/signaling for the first local URL in lib.rs, touching the same local-URL availability behavior.

Suggested reviewers

• veeso
• matthme

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title directly aligns with the main change: fixing a race condition where URLs weren't available before relay connection initialization.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing touches

• 📝 Generate docstrings

---

---

📜 Recent review details

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between b075b1d and 0fcceb4.

📒 Files selected for processing (1)

• crates/transport_iroh/src/lib.rs

🚧 Files skipped from review as they are similar to previous changes (1)

• crates/transport_iroh/src/lib.rs

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (1)

• GitHub Check: Cloudflare Pages

_{✏️ Tip: You can disable this entire section by setting review_details to false in your review settings.}

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[github-actions]

The following will be added to the changelog

---

[0.4.0-dev.3] - 2026-01-15

Bug Fixes

• Abort orphaned tasks in error case
• Race condition - wait for the relay connection before completing initialization

[coderabbitai]

Actionable comments posted: 1

📜 Review details

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 2b809bc and b075b1d.

📒 Files selected for processing (1)

• crates/transport_iroh/src/lib.rs

🧰 Additional context used

🧬 Code graph analysis (1)

crates/transport_iroh/src/lib.rs (3)

crates/api/src/url.rs (2)

• as_ref (74-76)
• addr (214-221)

crates/api/src/transport.rs (1)

• url (398-398)

crates/transport_iroh/src/url.rs (1)

• get_url_with_first_relay (5-21)

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (1)

• GitHub Check: Cloudflare Pages

🔇 Additional comments (3)

crates/transport_iroh/src/lib.rs (3)

221-230: LGTM!

The oneshot channel pattern is correctly implemented to signal URL readiness. The sender is properly passed to the spawned task, and the receiver will be awaited with a timeout.

---

275-284: LGTM!

The function signature change is well-designed. Using Option<...> maintains flexibility, and the mutable binding enables the .take() pattern for one-time signaling.

---

286-318: LGTM!

The logic correctly identifies the first URL by checking guard.is_none() before the update. The .take() pattern ensures one-time signaling, and releasing the write lock before signaling is good practice to avoid holding locks during async operations.

_{✏️ Tip: You can disable this entire section by setting review_details to false in your review settings.}

[cloudflare-workers-and-pages]

Deploying kitsune2 with    Cloudflare Pages

Latest commit:	0fcceb4
Status:	✅  Deploy successful!
Preview URL:	https://91089171.kitsune2.pages.dev
Branch Preview URL:	https://fix-url-race-condition.kitsune2.pages.dev

View logs

[jost-s]

This could be a useful change. I would simplify the main connection task and pass in the local URL instead of an option.

But in the larger picture, this is something that kitsune should handle better. When a local URL is received from the relay, new_listening_address is called. I think kitsune shouldn't act before it doesn't have a listening address. Then this issue wouldn't occur.