Files
felhom-controller/controller/internal
admin ff058a4f10 E-2 Part 1: the backup-target role on StoragePath (foundation, not yet wired)
Foundation only, no version bump -- nothing customer-visible changes yet. The
offer UI (Part 3), the degraded banner (Part 4) and the controller half of the
absent-target signal (Part 5) are NOT here; they are tracked as E-2 in
OPEN-ITEMS.md so this cannot become a sixth "seam built but never wired". The
fifth was found by E-2's own Phase 0: NotifyStorageDisconnected is defined and
called nowhere, so a drive going absent emits no event at all today.

StoragePath gains BackupTarget bool -- the sibling role to Schedulable/
IsDefault/Kind. It is INTENT, not truth: the authority is the agent's
backup.local_backup_target, and truth is read from GET /backup/tiers. This
records what the customer ASSIGNED so the controller can render the state,
notice the drive going absent, and detect drift.

Invariants, each pinned by a test asserting the CONSEQUENCE not the mechanism:
  - a drive NEVER acquires the role by appearing (registration does not set it)
  - exactly one carrier; assigning moves rather than duplicates
  - sticky: a new bigger/faster drive does not steal an assigned target
  - an absent target STAYS assigned -- clearing on disconnect would be a silent
    retarget by omission ("no target configured" instead of "drive missing")
  - a network share is refused (R-108 risk model; the role is about LOCAL disk
    failure)

Red-proof C: adding auto-elevation to AddStoragePath fails
TestRegisteringDrivesNeverAssignsTheBackupTarget with
  registering drives assigned the backup target "/mnt/hdd_1"

Attributes may suggest and refuse the absurd, never select: demo-felhom's backup
drive is an external USB HDD and BOTH demo boxes report removable=0, so a
transport rule disqualifies the reference drive and a removable rule finds no
candidate at all.

Green gate: build + vet + test rc=0, run separately from this commit.
2026-07-29 08:00:47 +02:00
..