fix(voip): dial relays on the web client port

[jlucaso1]

Why

connectRelays pins every relay connection to 3478. A relay answers only on the port it advertises, and reaching one on 3478 completes the handshake and carries the uplink without ever forwarding the peer's stream back, so the call is silently one way and nothing surfaces as an error.

WhatsApp Web names the two ports itself:

var e = { CLOSE_OLD_CONNECTION_BEFORE_CALL_END: !1, FAUX_WEB_CLIENT_RELAY_PORT: 3478, TRUE_WEB_CLIENT_RELAY_PORT: 3480, USE_AUTH_TOKEN_FOR_ICE: !0 }

and builds its connection map with portOverride: (port) => shouldUseOriginalRelayPort() ? port : TRUE_WEB_CLIENT_RELAY_PORT, so by default it dials every candidate on 3480 and keeps the advertised port only as originalPort.

Overriding the advertised port is therefore right, which is why this is not a change of shape. The value was the faux one, and 3480 is already in the package as CONFIG.TRUE_WEB_CLIENT_RELAY_PORT, the fallback configureRelays applies to an endpoint that carries no port.

The gate is worth mirroring too. As it stands a relay is only ever reachable on one fixed port, however the <te2> block addresses it, and nothing outside the plugin can change that.

What

port: TRUE_WEB_CLIENT_RELAY_PORT, and the generated name follows it. The constant moves next to the behaviour it explains and is exported, so CONFIG and the media session share one definition instead of two literals.

useOriginalRelayPort, default false, dials the port each endpoint advertises instead. It threads down the same path maxConcurrentCalls already takes, and the doc comment says plainly that it is the wrong choice against WhatsApp's own relays.

plugins: [voipPlugin({ useOriginalRelayPort: true })]

Notes

The port policy could instead live in WaSctpRelay, whose configureRelays already applies relay.port || CONFIG.TRUE_WEB_CLIENT_RELAY_PORT, with the session passing ep.port through. That puts one place in charge of the dialled port. Happy to move it if you prefer that shape.

Tests

Five in packages/voip/src/call/__tests__/media-session-relays.test.ts, on what reaches configureRelays: relays are dialled on the web client port, an endpoint advertising the faux port is dialled there too, an unnamed relay is named for the address it dials, the escape hatch dials the advertised port, and two ports on one host stay two relays under it. The first three fail on master.

npm test in packages/voip passes (77 tests); tsc --noEmit, ESLint and Prettier clean.

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ℹ️ Recent review info

⚙️ Run configuration

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Run ID: af3a2da4-c2d1-405b-aeb6-c36cf0901d36

📥 Commits

Reviewing files that changed from the base of the PR and between ecf0129 and 714cfdf.

📒 Files selected for processing (4)

• .changeset/voip-relay-advertised-port.md
• packages/voip/src/call/WaCallMediaSession.ts
• packages/voip/src/call/__tests__/media-session-relays.test.ts
• packages/voip/src/relay/WaSctpRelay.ts

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

• packages/voip/src/call/WaCallMediaSession.ts

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📝 Walkthrough

Walkthrough

The VoIP relay configuration now uses the shared TRUE_WEB_CLIENT_RELAY_PORT constant set to 3480. Tests verify relay IP preservation, port replacement, and fallback names for unnamed relays.

Changes

VoIP relay port handling

Layer / File(s)	Summary
Define the web-client relay port packages/voip/src/relay/WaSctpRelay.ts	Exports TRUE_WEB_CLIENT_RELAY_PORT with value 3480 and uses it in CONFIG.
Apply the relay port to media sessions packages/voip/src/call/WaCallMediaSession.ts, .changeset/voip-relay-advertised-port.md	WaCallMediaSession uses the shared constant for relay ports and fallback names. The changeset documents the port change.
Validate relay configuration packages/voip/src/call/__tests__/media-session-relays.test.ts	Tests verify relay IP preservation, port replacement, and fallback names using the configured port.

Estimated code review effort: 2 (Simple) | ~10 minutes

Merge Risk: 🟡 Moderate · up to 714cf

The current behavior still forces relay connections to port 3478, which can make relays advertising another port unreachable and collapse distinct same-host relay endpoints. The PR is not merge-ready until advertised ports are preserved and the fallback is applied only when no port is provided.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 33.33% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: dialing VoIP relays on the web client port.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[cubic-dev-ai]

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