docs(adr): amend 0001 + 0003 — baseline provenance and validation; glossary terms for verified and unverified override

2026-08-31 21:02:09 +05:30
parent d45d931a0d
commit 4d332bef53
3 changed files with 15 additions and 3 deletions
@@ -4,6 +4,8 @@

 Accepted — resolves [Define the persistent observation store and legacy migration](https://git.bongbetic.com/xavierk/Fenris/issues/2) on the [Wayfinder map](https://git.bongbetic.com/xavierk/Fenris/issues/1).

+Amended by [Define endurance-baseline provenance and validation](https://git.bongbetic.com/xavierk/Fenris/issues/12): the `endurance_baseline` field set and validation contract — derived verification, entry-time unprivileged sysfs validation, and read-time controller-segment applicability.
+
 ## Context

 Fenris today persists full SMART samples to an append-only `data/history.jsonl` beside a derived `data/hourly.jsonl`, both in the checkout, with no schema versioning and silent skipping of malformed lines. The redesign replaces the HTML dashboard with a keyboard-first TUI backed by a short-lived privileged collector on a systemd timer and an unprivileged TUI ([lifecycle research](https://git.bongbetic.com/xavierk/Fenris/src/branch/research/systemd-privilege-lifecycle/docs/research/systemd-privilege-lifecycle.md)), and projects a usage-adjusted theoretical lifespan from Data Units Written over wall-clock time with categorical confidence ([endurance research](https://git.bongbetic.com/xavierk/Fenris/src/branch/research/nvme-endurance-signals/docs/research/nvme-endurance-signals.md)). The store must support a root writer appearing every few minutes while an unprivileged reader queries concurrently, must migrate the legacy observation history idempotently and interruption-safely, and must version its schema.
@@ -18,7 +20,7 @@ Fenris today persists full SMART samples to an append-only `data/history.jsonl`
    - `day_aggregates` — one row per UTC day; the habit-evidence grain.
    - `monitoring_periods` — `started_at`, `ended_at` (NULL = open), `end_cause` enum (`user_disabled`, `migrated`, …). Powered-off time stays inside a period; deliberately disabled time does not.
    - `controller_segments` — boundaries where controller identity changes or DUW decreases; write deltas are never computed across a segment.
-    - `endurance_baseline` — verified rated-TBW override in bytes plus provenance (source URL, document revision, entry date).
+    - `endurance_baseline` — one active row, replaced on edit ([Define endurance-baseline provenance and validation](https://git.bongbetic.com/xavierk/Fenris/issues/12)): the rated-TBW value in bytes (`E_rated = entered_TBW × 10¹²`) plus mandatory provenance — source URL, document revision, entry date, model string, nominal capacity — and frozen validation facts (detected model, detected capacity bytes, `validated_by` `machine`/`user`, `validated_at`). Verification is derived at read — complete provenance and a drive match (machine or attested), never a stored boolean; incomplete provenance stores only behind an explicit unverified acknowledgment, as NULL fields in that precedence tier. Entry validation is an unprivileged live sysfs read of the configured device (normalized model containment with an interactive confirm recorded as `validated_by = user`; capacity within ±1%); at projection time applicability is a model match against the current controller segment, and a mismatch is retained — never auto-deleted — leaving the projection Unavailable.
    - Projections are not stored; they are recomputed on read. There is no separate latest-status table.
 4. **Day boundary**: UTC, matching hours, so day derivation from hour rows is monotonic and DST-ambiguous or 23/25-hour days never exist in the store.
 5. **Retention**: raw samples are kept 14 days and pruned opportunistically by the collector; hour observations and day aggregates are retained indefinitely.
@@ -4,6 +4,8 @@

 Accepted — resolves [Define the collector, service, and CLI lifecycle](https://git.bongbetic.com/xavierk/Fenris/issues/8) on the [Wayfinder map](https://git.bongbetic.com/xavierk/Fenris/issues/1). Amends the toggle mechanism of [Verify systemd lifecycle and privilege constraints](https://git.bongbetic.com/xavierk/Fenris/issues/7); its spirit — scoped, explicit, authenticated, no generic `manage-unit-files` grant — is intact.

+Amended by [Define endurance-baseline provenance and validation](https://git.bongbetic.com/xavierk/Fenris/issues/12): the helper gains a `baseline` verb that persists the CLI-validated endurance-baseline row — same fixed-operation, polkit-mediated pattern.
+
 ## Context

 Fenris's current single process combines daemonization, a PID file, an HTTP dashboard, and control (`fenris.py start/stop/status/sample`) over checkout-relative state. [ADR 0001](0001-observation-store-sqlite.md) fixed the observation store, including `monitoring_periods` whose `user_disabled` end cause records deliberate pauses, and the [systemd lifecycle research](https://git.bongbetic.com/xavierk/Fenris/src/branch/research/systemd-privilege-lifecycle/docs/research/systemd-privilege-lifecycle.md) fixed the timer + oneshot architecture, standard paths, journal diagnostics, allow-listed status reads, and polkit-mediated startup toggles — while leaving cadence mechanics, the configuration surface, CLI compatibility, staleness thresholds, and the mechanism that records a deliberate disable open. In particular, `systemctl enable`/`disable` cannot write a monitoring-period row, so a direct-systemctl toggle cannot satisfy the store's semantics.
@@ -13,7 +15,7 @@ Fenris's current single process combines daemonization, a PID file, an HTTP dash
 1. **Units.** Two system units only: `fenris-collect.timer` (`WantedBy=timers.target`) and `fenris-collect.service` (`Type=oneshot`, root, `ExecStart=/usr/libexec/fenris/fenris-collect`; no listener, no UI code). The TUI and CLI are ordinary unprivileged processes and never units. There is no `/run/fenris` coordination surface: systemd serializes runs, the observation store holds state, and failures go to the journal per [ADR 0001](0001-observation-store-sqlite.md).
 2. **Cadence.** Default five minutes: `OnBootSec=2min`, `OnUnitInactiveSec=5min` (measured from run completion; drift accepted because hours are the evidence grain), `AccuracySec=30s`, `Persistent=no`, no suspend catch-up (absent hours classify through power-on-hours evidence), `TimeoutStartSec=90s` so a hung interrogation fails visibly. Cadence changes are documented drop-ins on the timer unit (`systemctl edit` + daemon-reload); no interval key exists in configuration.
 3. **Configuration.** `/etc/fenris/fenris.conf` holds exactly one key: the device selector, a stable `/dev/disk/by-id/…` path (raw nodes accepted with an instability warning), validated at collection time. The oneshot re-reads it every run, so there is no reload path to design. An invalid selector is a bounded failed run — journal plus failed unit result, retried next interval; `status` and the TUI also read the world-readable file directly and surface a `configuration error: <reason>` fact.
-4. **Entry points.** Two privileged binaries: `/usr/libexec/fenris/fenris-collect` (device interrogation and store writes; the unit's `ExecStart`) and `/usr/libexec/fenris/fenris-monitor` (fixed operations `enable` and `disable` with optional `--now`, plus the collect trigger and monitoring-period bookkeeping; the only binary the polkit policy authorizes). One unprivileged `fenris` for humans: no arguments opens the TUI; subcommands (`status`, `sample`, `monitor pause`, `monitor resume`) are the CLI.
+4. **Entry points.** Two privileged binaries: `/usr/libexec/fenris/fenris-collect` (device interrogation and store writes; the unit's `ExecStart`) and `/usr/libexec/fenris/fenris-monitor` (fixed operations `enable` and `disable` with optional `--now`, plus the collect trigger, monitoring-period bookkeeping, and `baseline set`/`baseline clear` persistence for the CLI-validated endurance baseline; the only binary the polkit policy authorizes). One unprivileged `fenris` for humans: no arguments opens the TUI; subcommands (`status`, `sample`, `monitor pause`, `monitor resume`) are the CLI.
 5. **Sanctioned toggle.** Pause = `disable --now`; Resume = `enable --now`; both executed by `fenris-monitor`, which performs the systemctl operation and the monitoring-period bookkeeping in one step, under polkit action `com.bongbetic.fenris.monitor` (`auth_admin`, covering the collect trigger too). Root invokes the helpers directly; where no polkit agent exists the operation fails cleanly and prints the root equivalent. This amends the research's direct-systemctl toggle: a period boundary cannot be recorded by systemctl, so the toggle must be Fenris's own fixed operation.
 6. **Period rows.** Idempotent matrix: a first-ever enable opens a period at the enable moment (hours before the first successful sample are unknown-but-inside, correctly so when the device errors); a resume with an open period — a raw `systemctl stop` intervened — changes no row, the gap remaining inside as unknown seconds; a resume with no open period opens a new row at the resume moment; a pause with an open period closes it `user_disabled` at the pause moment; a pause otherwise is a no-op. A raw stop or disable outside the helper is an unexplained gap, never `user_disabled`: only the sanctioned path can record intent.
 7. **On-demand collection.** `fenris sample` and the TUI's collect-now route through `fenris-monitor` → `systemctl start fenris-collect.service`, which blocks until the oneshot exits, and the outcome (freshness line or journal hint) is reported synchronously. No code path outside `fenris-collect` touches the device; the TUI never samples in-process; no confirmation is required.