mirror of
https://github.com/permissionlesstech/bitchat.git
synced 2026-07-25 00:25:19 +00:00
Outgoing kind-20000 geohash messages mine a NIP-13 nonce tag (8 leading zero bits, ~256 hashes, typically <1 ms) off the main actor before signing. Mining is hard-capped at 2 s and cancellable (newer send or channel switch): on cap/cancel the committed target steps down so the message still ships promptly with an honest commitment - sending is never blocked and nothing is dropped. The hot loop serializes the canonical event once and rewrites only the fixed-width nonce bytes. Inbound kind-20000 events are scored per NIP-13 commitment semantics (committed target counts; the ID must actually meet it, extra work earns nothing) and never hard-rejected: validated PoW >= 8 bits skips the per-sender rate-limit bucket while the per-content flood bucket still applies, so old non-mining clients keep working under today's strict limits while bulk spam gets expensive. Presence heartbeats (kind 20001), kind-1 notes, and DMs are unchanged; no UI beyond a pow= field in an existing sampled debug log. Reimplemented from scratch rather than cherry-picking the stale feature/pow-geohash-mining-ui branch (unbounded loop, hard receive filtering, mining UI, XCTest, force unwraps). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Test Harness Guide
This test suite uses an in-memory networking harness to make end-to-end and integration tests deterministic, fast, and race-free without touching production code.
In-Memory Bus
- File:
bitchatTests/Mocks/MockBLEService.swift - Registry/Adjacency: Global
registrymapspeerIDto aMockBLEServiceinstance;adjacencyrecords simulated links between peers. - Setup: Call
MockBLEService.resetTestBus()insetUp()to clear state between tests. - Topology: Use
simulateConnectedPeer(_:)andsimulateDisconnectedPeer(_:)to add/remove links.connectFullMesh()helpers in tests build larger topologies. - Handlers: Tests can observe data via
messageDeliveryHandler(decodedBitchatMessage) andpacketDeliveryHandler(rawBitchatPacket). - De‑duplication: A thread-safe
seenMessageIDsprevents duplicate deliveries during flooding/relays.
Broadcast Flooding
- Flag:
MockBLEService.autoFloodEnabled - Intent: When
true, public broadcasts propagate across the entire connected component (ignores TTL for reach) while still de‑duping to prevent loops. - Usage: Enabled in Integration tests (
setUp) to simulate large-network broadcast; disabled in E2E tests to keep routing explicit and verify TTL behavior (seePublicChatE2ETests.testZeroTTLNotRelayed).
Rehandshake Flow (Noise)
- Why: The legacy NACK recovery path was removed; recovery now relies on Noise session rehandshake after decrypt failure or desync.
- Manager:
NoiseSessionManagermanages per-peer sessions. - Pattern: On decrypt failure, proactively clear the local session and re-initiate a handshake. The peer accepts and replaces their session.
- Test:
IntegrationTests.testRehandshakeAfterDecryptionFailure- Corrupts ciphertext to induce a decrypt error.
- Calls
removeSession(for:)on the initiator’s manager beforeinitiateHandshake(with:)to avoidalreadyEstablished. - Verifies encrypt/decrypt succeeds post-rehandshake.
Tips
- Determinism: Add small async delays only where handler installation/topology changes could race the first send.
- Scoping: Keep
autoFloodEnabledtoggled only within Integration tests; always reset intearDown()to avoid cross-test contamination. - Direct vs Relay: Private messages target a specific peer when adjacent; otherwise they are surfaced to neighbors for relay and, if known, also delivered to the target.
Quick Start
- Create nodes and connect them:
let svc = MockBLEService(); svc.myPeerID = "PEER1"svc.simulateConnectedPeer("PEER2")
- Observe messages:
svc.messageDeliveryHandler = { msg in /* asserts */ }
- Enable broadcast flooding for Integration suites only:
MockBLEService.autoFloodEnabled = true