led-sync-studio/.planning/phases/02-app-core-audio/02-02-SUMMARY.md

phase, plan, subsystem, tags, requires, provides, affects, tech-stack, key-files, key-decisions, patterns-established, requirements-completed, duration, completed

phase	plan	subsystem	tags	requires	provides	affects	tech-stack	key-files	key-decisions	patterns-established	requirements-completed	duration	completed
02-app-core-audio	02	transport	asyncio udp esp32 datagram-protocol json led-control	phase provides 01-esp32-firmware UDP JSON protocol spec (docs/protocol.md) — port 4210, v:1 commands, STATUS response format	ESP32Transport: asyncio.DatagramProtocol for fire-and-forget UDP JSON commands to ESP32 create_esp32_transport(): async factory coroutine returning ready ESP32Transport Connection state tracking (connected/disconnected) via STATUS ok responses led_sync.transport package with clean re-exports	02-04-scheduler 02-05-repl 03-tui	added patterns pytest-asyncio>=0.23 asyncio.DatagramProtocol for non-blocking UDP fire-and-forget v:1 protocol version injected by transport layer, not callers TDD red-green cycle for protocol-critical transport behavior	created modified src/led_sync/transport/__init__.py src/led_sync/transport/udp_client.py tests/test_transport.py pyproject.toml	D-10: asyncio DatagramProtocol, fire-and-forget sendto() — no blocking anywhere in send path D-11: send_status_ping() for optional heartbeat, non-blocking D-12: connected=True set only upon STATUS ok response, not upon socket bind D-14: Minimal error handling — silent drop on oversized payload, malformed JSON, pre-connection calls Protocol version v:1 injected by send_command(), callers never need to include it	Pattern 1: asyncio.DatagramProtocol subclass for ESP32 UDP transport (fire-and-forget, no awaits in send path) Pattern 2: Silent drop pattern — no exceptions from transport layer, only debug/warning logs Pattern 3: on_status callback for reactive STATUS response handling without polling	CHR-05	4min	2026-04-03

Phase 02 Plan 02: ESP32 UDP Transport Client Summary

asyncio DatagramProtocol UDP client for ESP32 on port 4210 — fire-and-forget JSON commands with STATUS-based connection tracking

Performance

• Duration: 4 min
• Started: 2026-04-03T12:15:55Z
• Completed: 2026-04-03T12:19:45Z
• Tasks: 1 (TDD: test commit + feat commit)
• Files modified: 4

Accomplishments

• ESP32Transport implements asyncio.DatagramProtocol with all protocol behaviors matching docs/protocol.md exactly
• send_command() injects v:1, enforces 512-byte limit, silently drops if pre-connection — all non-blocking
• STATUS ok responses parsed in datagram_received() to set connected=True and store last_status
• 15 unit tests covering all public behaviors including async factory and oversized payload drop
• create_esp32_transport() async factory sends initial STATUS ping for D-12 connection bootstrap

Task Commits

1. RED — Failing tests for ESP32Transport - f10fcf0 (test)
2. GREEN — ESP32Transport implementation - 378620e (feat)

Files Created/Modified

• src/led_sync/transport/udp_client.py — ESP32Transport class + create_esp32_transport() factory
• src/led_sync/transport/__init__.py — Package marker, re-exports ESP32Transport and create_esp32_transport
• tests/test_transport.py — 15 unit tests covering all protocol behaviors
• pyproject.toml — Added pytest-asyncio to dev deps, asyncio_mode=auto

Decisions Made

• Protocol version field v:1 is injected by send_command() — callers never include it (cleaner downstream API)
• on_status callback parameter in ESP32Transport constructor and create_esp32_transport() factory for reactive status handling without polling
• Silent drop on pre-connection and oversized payload (no exceptions) matches D-14 fire-and-forget philosophy

Deviations from Plan

Auto-fixed Issues

1. [Rule 3 - Blocking] Added pytest-asyncio dependency for async test support

• Found during: Task 1 (TDD RED phase)
• Issue: Tests use @pytest.mark.asyncio but pytest-asyncio was not in pyproject.toml dev deps; test would fail with UnknownMarkWarning and no async test support
• Fix: uv add --dev pytest-asyncio and added asyncio_mode = "auto" in [tool.pytest.ini_options]
• Files modified: pyproject.toml, uv.lock
• Verification: All 15 tests pass including async factory test
• Committed in: 378620e (Task 1 GREEN commit)

2. [Rule 3 - Blocking] Discovered pyproject.toml and led_sync package already existed

• Found during: Task 1 setup
• Issue: Plan 02-01 (scaffold) has not been committed to git yet, but the pyproject.toml and src/led_sync/ structure already existed on disk from a previous partial execution
• Fix: Worked with existing files; only added transport package and pytest-asyncio
• Files modified: None (existing structure was sufficient)
• Verification: uv run python -c "from led_sync.transport import create_esp32_transport" exits 0

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Total deviations: 2 auto-fixed (2x Rule 3 blocking) Impact on plan: Both fixes necessary for test infrastructure and working with existing project state. No scope creep.

Issues Encountered

None beyond the deviations documented above.

User Setup Required

None — no external service configuration required.

Next Phase Readiness

• from led_sync.transport import create_esp32_transport is importable and ready for use
• Scheduler (02-04) and REPL (02-05) can depend on transport.send_command(dict) and transport.connected interfaces
• Transport is fully tested with 15 unit tests covering all edge cases

Self-Check: PASSED

All created files verified present. Both commits (f10fcf0, 378620e) confirmed in git log.

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Phase: 02-app-core-audio Completed: 2026-04-03