tcptop/.planning/milestones/v1.0-phases/03-output-distribution/03-01-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
03-output-distribution	01	output	csv serde chrono headless logging	phase provides 01-data-pipeline ConnectionRecord model and ConnectionTable aggregator phase provides 02-interactive-tui Cli struct with clap derive, run_linux TUI event loop	CsvRow and CsvLogger for CSV snapshot output --log <path> CLI flag for headless mode run_headless async event loop (no TUI dependency)	03-output-distribution	added patterns serde 1.x csv 1.4 chrono 0.4 tempfile 3 (dev) TDD red-green for new modules headless/TUI branch before terminal init	created modified tcptop/src/csv_writer.rs tcptop/tests/csv_test.rs Cargo.toml tcptop/Cargo.toml tcptop/src/lib.rs tcptop/src/main.rs	CSV uses serde Serialize derive for type-safe column mapping (16 fields) Headless branch before ratatui::init prevents terminal corruption Single timestamp per tick ensures CSV row consistency	TDD for new modules: write failing tests first, then implement Headless mode shares collector/aggregator setup with TUI mode	OUTP-01 OUTP-02 OPS-05	3min	2026-03-22

Phase 03 Plan 01: CSV Logging Summary

CSV logging with headless mode via --log flag using serde/csv crate, 6 tests covering header, field count, overwrite, timestamp consistency, rate precision, and protocol state

Performance

• Duration: 3 min
• Started: 2026-03-22T04:47:40Z
• Completed: 2026-03-22T04:50:43Z
• Tasks: 2
• Files modified: 6

Accomplishments

• CsvRow struct with 16 serde-serialized fields mapping from ConnectionRecord
• CsvLogger with file creation (overwrite) and flushed snapshot writes
• --log CLI flag branching to headless event loop before terminal init
• 6 focused CSV tests covering all specified behaviors

Task Commits

Each task was committed atomically:

1. Task 1 (RED): Add failing CSV tests - f3ce244 (test)
2. Task 1 (GREEN): Implement CsvRow and CsvLogger - 8a36ae8 (feat)
3. Task 2: Add --log flag and headless event loop - 39e807d (feat)

TDD task had separate RED and GREEN commits.

Files Created/Modified

• tcptop/src/csv_writer.rs - CsvRow (Serialize) and CsvLogger (write_snapshot with flush)
• tcptop/tests/csv_test.rs - 6 tests: header, field count, overwrite, timestamp, rate precision, state/rtt
• Cargo.toml - Added serde, csv, chrono workspace dependencies
• tcptop/Cargo.toml - Added serde, csv, chrono deps; tempfile dev-dep
• tcptop/src/lib.rs - Added pub mod csv_writer
• tcptop/src/main.rs - Added --log flag, run_headless async fn, headless/TUI branching

Decisions Made

• Used serde Serialize derive for CsvRow to get automatic header generation and type-safe field mapping
• Headless mode branches before ratatui::init() to avoid terminal corruption (critical ordering)
• Single Utc::now().to_rfc3339() call per tick ensures all rows in a snapshot share the same timestamp
• Rate values rounded to 2 decimal places via (x * 100.0).round() / 100.0

Deviations from Plan

None - plan executed exactly as written.

Issues Encountered

None

User Setup Required

None - no external service configuration required.

Next Phase Readiness

• CSV output module ready for use
• Headless mode compiles and is reachable via --log flag
• Ready for packaging/distribution tasks in subsequent plans

Self-Check: PASSED

All 4 created/modified files verified on disk. All 3 commit hashes found in git log.

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Phase: 03-output-distribution Completed: 2026-03-22