---
phase: 01.1-hexagonal-architecture
plan: 04
subsystem: logging
tags: [vitest, events, logging, file-io, eventbus]

# Dependency graph
requires:
  - phase: 01.1-01
    provides: EventBus port interface, LogEntryEvent type
provides:
  - Comprehensive LogManager test coverage
  - Comprehensive ProcessLogWriter test coverage
  - Event emission for log entries (stdout/stderr)
  - Real-time log streaming capability via EventBus
affects: [01.1-05, 01.1-06, 07-FSUI]

# Tech tracking
tech-stack:
  added: []
  patterns: [event-driven-logging, optional-dependency-injection]

key-files:
  created:
    - src/logging/manager.test.ts
    - src/logging/writer.test.ts
  modified:
    - src/logging/writer.ts
    - src/logging/index.ts

key-decisions:
  - "EventBus is optional parameter for backwards compatibility"
  - "Events emitted after file write completes for consistency"
  - "Buffer data converted to string for event payload"

patterns-established:
  - "Optional EventBus injection pattern for modules"
  - "Log streaming via log:entry events"

# Metrics
duration: 4min
completed: 2026-01-30
---

# Phase 1.1 Plan 04: Logging Module Tests + Events Summary

**Comprehensive test coverage for LogManager and ProcessLogWriter with optional EventBus integration for real-time log streaming**

## Performance

- **Duration:** 4 min
- **Started:** 2026-01-30T14:00:00Z
- **Completed:** 2026-01-30T14:04:00Z
- **Tasks:** 2
- **Files modified:** 4

## Accomplishments

- 35 unit tests for LogManager covering directory operations, path resolution, log listing, and retention cleanup
- 24 unit tests for ProcessLogWriter covering file operations, timestamps, append mode, and event emission
- ProcessLogWriter accepts optional EventBus and emits log:entry events
- createLogger convenience function updated to support EventBus parameter
- Backwards compatible - eventBus parameter is optional

## Task Commits

Each task was committed atomically:

1. **Task 1: Write unit tests for LogManager and ProcessLogWriter** - `17f4e61` (test)
2. **Task 2: Add event emission to ProcessLogWriter** - `bac133d` (feat)

## Files Created/Modified

- `src/logging/manager.test.ts` - 17 tests for LogManager (directory creation, path resolution, log listing, cleanup)
- `src/logging/writer.test.ts` - 24 tests for ProcessLogWriter (file ops, timestamps, events, compatibility)
- `src/logging/writer.ts` - Added optional EventBus parameter, emits log:entry events on write
- `src/logging/index.ts` - Updated createLogger to accept optional EventBus

## Decisions Made

1. **Optional EventBus parameter** - Maintains backwards compatibility while enabling event emission
2. **Events emitted after file write** - Ensures file is written before event is emitted for consistency
3. **Buffer converted to string for events** - Event payload uses string for easier consumption by UI/subscribers

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered

None

## User Setup Required

None - no external service configuration required.

## Next Phase Readiness

- Logging module fully tested with 41 tests total
- LogEntry events flow through event bus for real-time streaming
- Ready for Phase 7 (FSUI) which will consume log events
- Ready for 01.1-05: Server Module Tests + Events

---
*Phase: 01.1-hexagonal-architecture*
*Completed: 2026-01-30*
