Files
Codeman/test/reliable-input-dedup.test.ts
T
Codeman maintainer 1255e28f6f fix(input): durable exactly-once input delivery so a dropped link can't lose a prompt
A "sent" prompt could vanish with no trace on a flaky connection (e.g. a train):
with local echo on, Enter cleared the overlay then sent over the WebSocket
fire-and-forget. On a half-open socket (readyState===OPEN, dead TCP) ws.send()
doesn't throw, so the frame was silently discarded, nothing was enqueued, and
navigator.onLine stayed true — the prompt was lost and never resent.

Replace the best-effort offline queue with a durable, acknowledged delivery layer:

- Client (app.js): every input frame is recorded with a stable clientId +
  monotonic per-session seq and persisted to localStorage BEFORE delivery, and
  only dropped on a server ACK. Delivered over WS (acked via {t:'ia',seq}) or,
  when the socket is down, POST in seq order (HTTP 2xx = ACK). A 2s sweep
  force-reconnects a WS whose oldest frame is unacked past 4s (half-open sockets
  never recover on their own); on reconnect/reload all pending frames re-deliver.
  Survives reconnects AND page reloads. Connection indicator shows pending count.
- Server: Session.shouldApplyInput(clientId, seq) applies each frame exactly once
  (bounded MRU map); ws-routes + POST /input dedup a redelivered seq but still ACK
  it (200 / {t:'ia'}), so an at-least-once resend can never type the prompt twice.
  Untagged input (curl/legacy) applies unconditionally — no behavior change.
- terminal-ui.js sendInput() (voice / keyboard-accessory / paste) now routes
  through the same durable layer.

Tests: test/reliable-input-dedup.test.ts (exactly-once semantics on the real
Session) + POST /input dedup route tests. Design: docs/reliable-input-delivery.md.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-19 16:58:40 +02:00

74 lines
3.2 KiB
TypeScript

/**
* @fileoverview Exactly-once input delivery — Session.shouldApplyInput dedup.
*
* Guards the server half of the reliable-input-delivery feature: the web client
* tags each input frame with a stable clientId + a monotonic per-session seq and
* redelivers anything it hasn't seen ACKed (a half-open socket silently drops
* frames on a flaky link). shouldApplyInput must apply each (clientId, seq)
* exactly once so a redelivery can never type the prompt twice — while still
* applying untagged input (curl/legacy) unconditionally at the call sites.
*
* See docs/reliable-input-delivery.md.
*/
import { describe, it, expect } from 'vitest';
import { Session } from '../src/session.js';
function makeSession(): Session {
// workingDir is the only required field; no PTY is spawned until start(),
// and TmuxManager no-ops under VITEST — so this is a cheap, side-effect-free
// instance for exercising the pure dedup bookkeeping.
return new Session({ workingDir: '/tmp' });
}
describe('Session.shouldApplyInput (exactly-once input dedup)', () => {
it('applies a fresh (clientId, seq) exactly once', () => {
const s = makeSession();
expect(s.shouldApplyInput('clientA', 1)).toBe(true);
// Same seq redelivered (lost ACK) — must NOT apply again.
expect(s.shouldApplyInput('clientA', 1)).toBe(false);
});
it('applies strictly increasing seqs and rejects stale ones', () => {
const s = makeSession();
expect(s.shouldApplyInput('c', 1)).toBe(true);
expect(s.shouldApplyInput('c', 2)).toBe(true);
expect(s.shouldApplyInput('c', 3)).toBe(true);
// Out-of-order / replayed lower seqs are duplicates.
expect(s.shouldApplyInput('c', 2)).toBe(false);
expect(s.shouldApplyInput('c', 1)).toBe(false);
// The next genuinely-new seq still applies.
expect(s.shouldApplyInput('c', 4)).toBe(true);
});
it('tracks each client independently', () => {
const s = makeSession();
expect(s.shouldApplyInput('a', 5)).toBe(true);
// A different client at seq 1 is not shadowed by client a's higher seq.
expect(s.shouldApplyInput('b', 1)).toBe(true);
expect(s.shouldApplyInput('b', 1)).toBe(false);
expect(s.shouldApplyInput('a', 6)).toBe(true);
});
it('tolerates a seq gap (skips never collapse a new seq to a duplicate)', () => {
const s = makeSession();
expect(s.shouldApplyInput('c', 1)).toBe(true);
// Client jumped seq (e.g. resumed after a reload that kept the counter).
expect(s.shouldApplyInput('c', 100)).toBe(true);
expect(s.shouldApplyInput('c', 100)).toBe(false);
expect(s.shouldApplyInput('c', 50)).toBe(false);
expect(s.shouldApplyInput('c', 101)).toBe(true);
});
it('keeps recent clients dedup-correct past the eviction bound', () => {
const s = makeSession();
// Far exceed MAX_INPUT_DEDUP_CLIENTS (256) with one-shot clients, then prove
// a freshly-active client is still deduped correctly (MRU eviction).
for (let i = 0; i < 400; i++) {
expect(s.shouldApplyInput(`oneshot-${i}`, 1)).toBe(true);
}
expect(s.shouldApplyInput('recent', 1)).toBe(true);
expect(s.shouldApplyInput('recent', 1)).toBe(false);
expect(s.shouldApplyInput('recent', 2)).toBe(true);
});
});