Code Review Findings
Dual Packet State System (Architectural Bug)
7. LiveView maintains two unsynchronized packet tracking systems
Files: lib/aprsme_web/live/map_live/index.ex, packet_processor.ex, display_manager.ex
System A: packet_state wrapping PacketManager/PacketStore (ETS-backed).
System B: all_packets, visible_packets, historical_packets as plain maps in assigns.
These are never synchronized:
- Real-time packets update System B but never touch System A
- Cleanup runs on System A but never touches System B
- Bounds filtering reads System A but display reads System B
PacketManager.extract_packet_ids uses different ID generation than PacketStore.generate_packet_id — stored packets can never be found through the manager API
Memory Issues
23. all_packets map in LiveView assigns holds 2000 full Ecto structs
File: lib/aprsme_web/live/map_live/packet_processor.ex:27-37
Each packet has 100+ columns. 2000 full structs per connected client. Never cleaned by handle_cleanup_old_packets (which only touches packet_state). Appears to be dead state — written to but never read.
Correctness Issues
40. PacketStore uses global named ETS table shared across all LiveViews
File: lib/aprsme_web/live/map_live/packet_store.ex:12, 114
Different LiveViews can overwrite each other's stored packets. TTL cleanup runs globally.
Completed
1. LiveView: Missing {:noreply, socket} in drain handler — crashes LiveView
2. ConnectionMonitor: Deadlock via self-RPC every 30 seconds
3. LiveView: get_callsign_key generates random keys for Ecto structs — breaks all dedup
4. Cluster: PacketDistributor never calls SpatialPubSub.broadcast_packet
5. LeaderElection: pid_alive?/2 treats {:badrpc, _} as truthy
5b. LeaderElection: Loser never detects lost registration after :global conflict resolution
6. SpatialPubSub: ensure_float/1 crashes on integer strings
8. N+1 query: has_weather_packets? per marker — batch query replaces N+1 individual calls
9. Duplicate packet transformation — every packet processed twice
10. batch_length/1 recomputes O(n) list length on every event arrival
11. check_batch_utilization calls length/1 four times in guards and body
12. StreamingPacketsPubSub does full ETS scan on every packet — replaced with tab2list
13. SpatialPubSub receives every packet twice in non-cluster mode — removed PubSub subscription
14. remove_markers_batch sends one WebSocket event per marker
15. Encoding.clean_control_characters allocates per grapheme for every string field — added fast-path
16. truncate_datetimes_to_second called twice per packet
17. Spatial queries don't use PostGIS GiST index — rewritten to use ST_MakeEnvelope with && operator
18. weather_only query uses 10-way OR — now uses indexed has_weather column
19. SpatialPubSub.get_intersecting_grid_cells generates 341 cells for date-line-crossing viewports
20. Cleanup O(n^2) packet comparison in LiveView — fixed with MapSet
21. ETS cache has no TTL — added TTL with lazy expiration
22. Monitor reference leak in StreamingPacketsPubSub
24. broadcast_async uses async_nolink but never awaits — orphaned reply messages
25. handle_info({:ssl, ...}) in Is module — connection uses :gen_tcp, not SSL
26. PacketPipelineSetup module — deleted
27. Archiver module — deleted
28. SystemMonitor — deleted
29. DbOptimizer.copy_insert — COPY FROM STDIN doesn't work through Postgrex
30. Router /health route — shadowed by endpoint HealthCheck plug
32. RateLimiterWrapper.count/2 and reset/1 — removed dead stubs
33. pubsub_config/0 branches return identical values — simplified
34. Three no-op send_heat_map_for_current_bounds functions — wired up to DisplayManager
35. placeholders option passed to Repo.insert_all — not a valid option
36. Circuit breaker half-open state never persisted
37. Process.cancel_timer(nil) crash risk in Is module
38. PacketPipelineSupervisor uses :one_for_one — changed to :rest_for_one
39. handle_update_time_display doesn't trigger re-renders — now touches assign
41. ConnectionMonitor memory calculation is inverted
42. Callsign.valid?/1 accepts any non-empty string — docstring examples are wrong
43. Encoding.latin1_to_utf8 and clean_control_characters fight each other — fixed C1 range
44. DeviceCache has unreachable outer try/rescue — removed
45. LiveDashboard and ErrorTracker are publicly accessible — moved behind auth
46. SQL injection in DbOptimizer table/column name interpolation
47. /ready and /status.json are rate-limited — moved to separate unrated pipeline
48. ShutdownHandler.terminate blocks 30s but scheduled messages never processed
49. DatabaseMetrics hardcodes pool metrics
50. PacketBatcher started outside supervision tree — added crash recovery with Process.monitor
