tcptop/.planning/milestones/v1.0-phases/01-data-pipeline/01-03-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
01-data-pipeline	03	data-pipeline	tokio aggregator streaming-output bandwidth-calculation connection-lifecycle	phase provides 01-data-pipeline/01 shared data model (ConnectionKey, ConnectionRecord, Protocol, TcpState) and privilege check phase provides 01-data-pipeline/02 LinuxCollector with eBPF kprobes, RingBuf event loop, CollectorEvent enum, proc_bootstrap	ConnectionTable aggregator with tick-based bandwidth rate calculation UDP flow timeout (5s idle expiry) TCP close lifecycle with [CLOSED] output Streaming stdout formatter with human-readable sizes Full tokio event loop wiring collector -> aggregator -> output Pipeline integration tests proving data flow without eBPF/root	02-tui 03-output-packaging	added patterns tokio-signal lib.rs re-export for integration testing tokio::select! event loop mpsc channel decoupling	created modified tcptop/src/aggregator.rs tcptop/src/output.rs tcptop/src/lib.rs tcptop/tests/pipeline_test.rs tcptop/src/main.rs	Created lib.rs to expose modules for integration testing (binary crates cant be imported by tests) Used tokio::signal instead of signal-hook crate for SIGINT/SIGTERM (already in tokio context) mpsc channel buffer 4096 to decouple RingBuf reader from aggregator processing	lib.rs re-exports pub modules; main.rs is thin wrapper tokio::select! multiplexes events, periodic tick, and signal handling ConnectionTable::tick() returns (active, closed) tuple for output	DATA-06 DATA-07	2min	2026-03-21

Phase 01 Plan 03: Data Pipeline Wiring Summary

Connection aggregator with tick-based bandwidth calculation, UDP timeout, TCP close lifecycle, and streaming stdout output wired through tokio event loop

Performance

• Duration: 2 min
• Started: 2026-03-21T23:20:27Z
• Completed: 2026-03-21T23:22:52Z
• Tasks: 2
• Files modified: 5

Accomplishments

• ConnectionTable processes all 5 CollectorEvent variants with bandwidth rate calculation per tick
• PID=0 enrichment for TcpStateChange events (inherits PID from existing connection record)
• UDP flows expire after 5s idle; closed TCP connections produce [CLOSED] line and are removed
• Human-readable formatters for bytes (500B, 2048 (2.0K)), rates (1.5KB/s), and RTT (5.0ms)
• Full tokio event loop with graceful SIGINT/SIGTERM shutdown
• 4 pipeline integration tests prove data flow from synthetic events through aggregator to output

Task Commits

Each task was committed atomically:

1. Task 1: Implement aggregator and output formatter - c091aaa (feat)
2. Task 2: Wire tokio event loop and pipeline tests - a99c088 (feat)

Files Created/Modified

• tcptop/src/aggregator.rs - ConnectionTable with tick-based rate calculation, UDP timeout, TCP close lifecycle
• tcptop/src/output.rs - Streaming stdout formatter with human-readable sizes, [CLOSED]/[PARTIAL] markers
• tcptop/src/lib.rs - Public module re-exports for integration testing
• tcptop/src/main.rs - Full tokio::select! event loop wiring collector, aggregator, and output
• tcptop/tests/pipeline_test.rs - 4 integration tests proving pipeline data flow

Decisions Made

• Created lib.rs to expose modules for integration testing -- binary crates cannot be imported by tests, so lib.rs re-exports pub modules
• Used tokio::signal instead of signal-hook crate for graceful shutdown since we're already in a tokio context
• mpsc channel buffer size 4096 to decouple the RingBuf reader from aggregator processing per anti-pattern guidance

Deviations from Plan

Auto-fixed Issues

1. [Rule 3 - Blocking] Created lib.rs for integration test access

• Found during: Task 2 (pipeline unit test)
• Issue: Binary crate modules cannot be imported by integration tests via tcptop::aggregator::*
• Fix: Created lib.rs that re-exports pub modules; main.rs uses tcptop:: imports
• Files modified: tcptop/src/lib.rs, tcptop/src/main.rs
• Verification: cargo test -p tcptop --test pipeline_test passes all 4 tests
• Committed in: a99c088 (Task 2 commit)

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Total deviations: 1 auto-fixed (1 blocking) Impact on plan: Standard Rust pattern for testable binaries. No scope creep.

Issues Encountered

None

User Setup Required

None - no external service configuration required.

Next Phase Readiness

• Phase 1 data pipeline complete: eBPF events flow from kernel through collector, aggregator, to formatted stdout
• Ready for Phase 2 (TUI) to replace streaming output with ratatui-based interface
• ConnectionTable API (tick, update, seed) provides the data layer the TUI will consume

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Phase: 01-data-pipeline Completed: 2026-03-21