Builds on Phase 1's SignalMessage::Reflect to probe N relays in
parallel through transient QUIC connections and classify the
client's NAT type for the future P2P hole-punching path. No wire
protocol changes — Phase 1's Reflect/ReflectResponse pair is
reused unchanged.
New client-side module (crates/wzp-client/src/reflect.rs):
- probe_reflect_addr(relay, timeout_ms): opens a throwaway
quinn::Endpoint (fresh ephemeral source port per probe,
essential for NAT-type detection — sharing one endpoint would
make a symmetric NAT look like a cone NAT), connects to _signal,
sends RegisterPresence with zero identity, consumes the Ack,
sends Reflect, awaits ReflectResponse, cleanly closes.
- detect_nat_type(relays, timeout_ms): parallel probes via
tokio::task::JoinSet (bounded by slowest probe not sum) and
returns a NatDetection with per-probe results + aggregate
classification.
- classify_nat(probes): pure-function classifier split out for
network-free unit tests. Rules:
* 0-1 successful probes → Unknown
* 2+ successes, same ip same port → Cone (P2P viable)
* 2+ successes, same ip diff ports → SymmetricPort (relay)
* 2+ successes, different ips → Multiple (treat as
symmetric)
Tauri command (desktop/src-tauri/src/lib.rs):
- detect_nat_type({ relays: [{ name, address }] }) -> NatDetection
as JSON. Takes the relay list from JS because localStorage
owns the config. Parse-up-front so a malformed entry fails
clean instead of as a probe error. 1500ms per-probe timeout.
UI (desktop/index.html + src/main.ts):
- New "NAT type" row + "Detect NAT" button in the Network
settings section. Renders per-probe status (name, address,
observed addr, latency, or error) plus the colored verdict:
* green Cone — shows consensus addr
* amber SymmetricPort / Multiple — must relay
* gray Unknown — not enough data
Tests:
- 7 unit tests in wzp-client/src/reflect.rs covering every
classifier branch (empty, 1 success, 2 identical, 2 diff ports,
2 diff ips, success+failure mix, pure-failure).
- 3 integration tests in crates/wzp-relay/tests/multi_reflect.rs:
* probe_reflect_addr_happy_path — single mock relay end-to-end
* detect_nat_type_two_loopback_relays_is_cone — two concurrent
relays, asserts both see 127.0.0.1 and classifier returns
Cone or SymmetricPort (accepted because the test harness
uses fresh ephemeral ports per probe which look like
SymmetricPort on single-host loopback)
* detect_nat_type_dead_relay_is_unknown — alive + dead port
mix, asserts the dead probe surfaces an error string and
the aggregator returns Unknown (only 1 success)
Full workspace test goes from 386 → 396 passing.
PRD: .taskmaster/docs/prd_multi_relay_reflect.txt
Tasks: 47-52 all completed
Next up: hole-punching (Phase 3) — use the reflected address in
DirectCallOffer/Answer and CallSetup so peers attempt a direct
QUIC handshake to each other, with relay fallback on timeout.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Lets a client ask its registered relay "what IP:port do you see for
me?" over the existing TLS-authenticated signal channel, returning
the client's server-reflexive address as a SocketAddr. Replaces the
need for a classic STUN deployment and becomes the bootstrap step
for future P2P hole-punching: once both peers know their own reflex
addrs, they can advertise them in DirectCallOffer and attempt a
direct QUIC handshake to each other.
Wire protocol (wzp-proto):
- SignalMessage::Reflect — unit variant, client -> relay
- SignalMessage::ReflectResponse { observed_addr: String } — relay -> client
- JSON-serde, appended at end of enum: zero ordinal concerns,
backward compat with pre-Phase-1 relays by construction (older
relays log "unexpected message" and drop; newer clients time out
cleanly within 1s).
Relay handler (wzp-relay/src/main.rs, signal loop):
- New match arm next to Ping reuses the already-bound `addr` from
connection.remote_address() and replies with observed_addr as a
string. debug!-level log on success, warn!-level on send failure.
Client side (desktop/src-tauri/src/lib.rs):
- SignalState gains pending_reflect: Option<oneshot::Sender<SocketAddr>>.
- get_reflected_address Tauri command installs the oneshot before
sending Reflect and awaits it with a 1s timeout; cleans up on
every exit path (send failure, timeout, parse error).
- recv loop's new ReflectResponse arm fires the pending sender or
emits a debug log for unsolicited responses — never crashes the
loop on malformed input.
- Integrated into invoke_handler! alongside the other signal
commands.
UI (desktop/index.html + src/main.ts):
- New "Network" section in settings panel with a "Detect" button
that displays the reflected address or a categorized warning
("register first" / "relay does not support reflection" / error).
Tests (crates/wzp-relay/tests/reflect.rs — 3 new, all passing):
- reflect_happy_path: client on loopback gets back 127.0.0.1:<its own port>
- reflect_two_clients_distinct_ports: two concurrent clients see
their own distinct ports, proving per-connection remote_address
- reflect_old_relay_times_out: mock relay that ignores Reflect —
client times out between 1000-1200ms and does not hang
Also pre-existing test bit-rot unrelated to this PR — fixed so the
full workspace `cargo test` goes green:
- handshake_integration tests in wzp-client, wzp-relay and
featherchat_compat in wzp-crypto all missed the `alias` field
addition to CallOffer and the 3-arg form of perform_handshake
plus 4-tuple return of accept_handshake. Updated to the current
API surface.
Results:
cargo test --workspace --exclude wzp-android: 386 passed
cargo check --workspace: clean
cargo clippy: no new warnings in touched files
Verification excludes wzp-android because it's dead code on this
branch (Tauri mobile uses wzp-native instead) and can't link -llog
on macOS host — unchanged status quo.
PRD: .taskmaster/docs/prd_reflect_over_quic.txt
Tasks: 39-46 all completed
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
