update CLAUDE.md with rewrite plan documentation reference in docs/pland directory

2026-07-07 06:40:27 +02:00
parent 56208c061e
commit 38e080814e
15 changed files with 676 additions and 0 deletions
@@ -0,0 +1,35 @@
+# Step 09: System Metrics
+
+Prerequisites: step 07 (API), step 08 (layout).
+Read `README.md` and `00-legacy-analysis.md` first.
+
+## Goal
+
+Port the legacy system page: CPU, RAM, disk, and repository size with min/max/avg aggregation.
+
+## Design
+
+Create package `de.hoennig.gittally.metrics`:
+
+- `SystemMetricsCollector` sampling every 60s (server profile only):
+  CPU used/idle from `/proc/stat` deltas, RAM from `/proc/meminfo`, disk from `java.nio.file.FileStore`, repo size via periodic `du -sk` (or a file walk) — throttle repo-size sampling (legacy ran `du` every cycle, which was expensive).
+- Keep running min/max/avg per metric since server start; persist aggregation state in the artifact root so restarts continue the series (legacy `system_state.dat`, but as JSON).
+- `GET /api/system` returning the current snapshot plus aggregates (legacy `system.json` fields are the reference).
+- `/system` HTML view in the step 08 layout, polling `/api/system` every 60s with the same error-badge rules.
+
+## Out of Scope
+
+- Alerting, historical time series, external monitoring integration.
+- Windows/macOS support beyond graceful degradation (missing `/proc` → metric shows "n/a").
+
+## Tests
+
+- Collector unit tests with fake `/proc` file content (read paths injectable).
+- Aggregation math: min/max/avg over samples, persistence round-trip.
+- Controller slice test for `/api/system`.
+- Graceful degradation when a source is unreadable.
+
+## Acceptance Criteria
+
+- `./gradlew ktlintFormat` then `./gradlew build` is green.
+- `/system` renders live values on Linux (manual smoke test; document in this file).