R-103: the Tier-2 refusal becomes an action

An app whose Tier-2 copy holds no file legs but a full recovery-unit mirror - 45 of the 53 catalog templates - was told to press a button on a DIFFERENT page. Since R-102 the data it is asking for is restorable from the copy it is looking at. New POST /backup/tier2/unit-restore and backupTier2UnitRestoreHandler: same guards, same restoreOpBlocked() refusal (R-351b), same async shape as the file restore beside it, plus a fail-closed pre-flight so the app is never stopped for a mirror that could not be opened. The outcome reuses unitRestoreOutcomeMsg and adds which copy overwrote the live data. The row offers the action where the refusal was, in a danger style, as a SEPARATE button. The two are not merged: one adds what is missing, the other overwrites. The confirm carries that difference in words and names the copy's date - and says so differently when that date is only an ATTEMPT (R-101). It is built from named Go constants rather than assembled inside an HTML attribute, so a test can assert it verbatim; fmtTimeStr now delegates to a package-level fmtRFC3339Local so the confirm and the outcome cannot render the same date two ways. tier2NoCoverageMsg is NARROWED to the case that remains - no legs and no openable unit - and still names the route that works. tier2UnitNotCoveredMsg is NOT deleted: it is appended where the FILE restore ran and is still exactly true of it. Tests C1-C2 and D1-D6 plus four more. Red-proofs: C1 (widen CanRestore to include HasUnit -> the unit-only cases fail), D6 (drop EndRestoreOp from the handler goroutine -> 'the restore never published a result').
2026-08-31 11:42:03 +02:00
parent 0f9b796615
commit 4c8f0d2919
6 changed files with 755 additions and 16 deletions
@@ -309,13 +309,12 @@ func (s *Server) templateFuncMap() template.FuncMap {
 		// moment the customer decides whether to restore — a UTC machine timestamp is not something a
 		// customer can reason about. Absolute rather than relative here on purpose: "3 napja" is fine on
 		// a status card, but a restore decision deserves the actual date.
-		"fmtTimeStr": func(s string) string {
-			t, err := time.Parse(time.RFC3339, s)
-			if err != nil {
-				return s
-			}
-			return t.In(loc).Format("2006-01-02 15:04")
-		},
+		//
+		// R-102: it delegates to the package-level fmtRFC3339Local so a HANDLER can render the same
+		// date the same way. The Tier-2 unit restore names the copy's date in its confirm (template)
+		// and again in its outcome (Go); two renderings of one decision that could disagree is how a
+		// customer ends up confirming one date and being told another.
+		"fmtTimeStr": fmtRFC3339Local,
 		"fmtTime": func(t time.Time) string {
 			if t.IsZero() {
 				return "–"
@@ -497,3 +496,14 @@ func (s *Server) templateFuncMap() template.FuncMap {
 		},
 	}
 }
+
+// fmtRFC3339Local renders an RFC3339 STRING as an absolute Budapest-local date-time, returning the
+// input unchanged when it does not parse. The ONE implementation behind the `fmtTimeStr` template
+// helper and every Go-side caller. See the comment on the funcmap entry for why it is shared.
+func fmtRFC3339Local(s string) string {
+	t, err := time.Parse(time.RFC3339, s)
+	if err != nil {
+		return s
+	}
+	return t.In(getTimezone()).Format("2006-01-02 15:04")
+}
@@ -1187,6 +1187,23 @@ type AppBackupRow struct {
 	Tier2StatusBadge    string // "Sikeres", "Hiba", "Fut...", "—"
 	Tier2SizeHuman      string

+	// R-102/R-103 — the SECOND predicate, and it is a second field on purpose.
+	//
+	//   Tier2UnitRestorable  the copy holds an OPENABLE recovery unit (manifest present and parseable)
+	//                        → the destructive „Teljes visszaállítás" action is offered
+	//   Tier2CopyDate        the RFC3339 stamp of the copy that action would write over live data with
+	//   Tier2CopyDateProven  false = that stamp is only an ATTEMPT clock, never a proven copy (R-101)
+	//
+	// Tier2UnitRestorable is NOT derived from Tier2LastStatus, Tier2SizeHuman or anything else on this
+	// row: it is computed from what the copy on disk actually holds, because a row that says a backup
+	// succeeded is not evidence that the package inside it can be opened.
+	Tier2UnitRestorable bool
+	Tier2CopyDate       string
+	Tier2CopyDateProven bool
+	// Tier2UnitConfirm is the assembled destructive-confirm sentence (tier2UnitConfirmMsg). Built in
+	// Go, not in the attribute, so it is one named string a test can assert verbatim.
+	Tier2UnitConfirm string
+
 	// Drive disconnected — app's home drive is currently disconnected
 	DriveDisconnected bool
 	// Tier2 destination drive is currently disconnected (backup paused, not failed)
@@ -1404,6 +1421,16 @@ func (s *Server) buildAppBackupRows(status *backup.FullBackupStatus) []AppBackup
 				row.Tier2LastError = cd.LastError
 				row.Tier2LastWarning = cd.LastWarning
 				row.Tier2SizeHuman = cd.LastSizeHuman
+				// R-102: ask the COPY, not the config. Tier2RestoreCoverage stats the recorded copy
+				// and reads its manifest, and it raises the same refusals the restore itself would —
+				// a disconnected destination, a pre-v2 layout — so an offer is never rendered for a
+				// copy the action would refuse. On any refusal the action is simply not offered; the
+				// row keeps rendering everything else it already showed.
+				if cov, covErr := s.backupMgr.Tier2RestoreCoverage(app.StackName); covErr == nil {
+					row.Tier2UnitRestorable = cov.CanRestoreUnit()
+					row.Tier2CopyDate, row.Tier2CopyDateProven = cov.Tier2CopyDate()
+					row.Tier2UnitConfirm = tier2UnitConfirmMsg(row.Tier2CopyDate, row.Tier2CopyDateProven)
+				}
 				switch cd.LastStatus {
 				case "ok":
 					row.Tier2StatusBadge = "Sikeres"
@@ -1580,18 +1607,102 @@ const monitoringIntegritySchedule = "Hetente, kimarado ellenorzest potol"
 // verbatim by tests — a silent edit to either is the way an honest message drifts back into a
 // comforting one.
 const (
-	// tier2NoCoverageMsg is shown when this app's data cannot come from the secondary copy at all.
-	// It NAMES the action that works rather than leaving a dead end: the keep-side recovery-unit
-	// restore on /backups/restore, which does restore named volumes and DB dumps (proven live,
-	// Campaign 9 A2). It also states plainly that no outage was taken, because the previous behaviour
-	// took one.
+	// tier2NoCoverageMsg is shown when this app's data cannot come from the secondary copy AT ALL —
+	// no file legs AND no openable recovery unit in the copy. It NAMES the action that works rather
+	// than leaving a dead end: the keep-side recovery-unit restore on /backups/restore, which does
+	// restore named volumes and DB dumps (proven live, Campaign 9 A2). It also states plainly that no
+	// outage was taken, because the previous behaviour took one.
+	//
+	// R-103 NARROWED IT. Until v0.229.0 this same sentence was also shown to the far commoner case —
+	// no file legs but a full unit mirror sitting in the copy — and it sent those customers to a
+	// button on another page for data that is now restorable on the page they are already looking at.
+	// tier2UnitAvailableMsg is that case now.
 	tier2NoCoverageMsg = "Ennek az alkalmazásnak az adatai nem ebből a másolatból állíthatók vissza — az alkalmazás nem állt le. Használd a Visszaállítás indítása gombot a Biztonsági mentés → Visszaállítás oldalon."

-	// tier2UnitNotCoveredMsg is appended wherever the restore DID run, so a clean result never reads
-	// as a clean bill of health for data the operation never opened.
+	// tier2UnitAvailableMsg (R-103) — the copy holds no restorable FILES, but it does hold an openable
+	// recovery unit, so the answer is the action beside this one, not a different page. It names the
+	// button by its own label and says why the two differ, because the difference is the whole reason
+	// they are not one button: this one overwrites.
+	tier2UnitAvailableMsg = "Ennek az alkalmazásnak az adatai nem fájlokban, hanem az alkalmazás saját adatbázisában és köteteiben vannak — az alkalmazás nem állt le. Ezeket a mellette lévő „Teljes visszaállítás a másolatból” gombbal tudod visszahozni ugyanerről a másolatról. Figyelem: az a művelet FELÜLÍRJA a jelenlegi adatokat, míg ez a gomb csak a hiányzó fájlokat pótolja."
+
+	// tier2UnitNotCoveredMsg is appended wherever the FILE restore DID run, so a clean result never
+	// reads as a clean bill of health for data the operation never opened.
+	//
+	// R-103: it is NOT deleted now that the unit is restorable. It is appended where the FILE restore
+	// ran, and it is still exactly true of that restore — the file merge still never opens the
+	// database or the named volumes. Deleting it would let a clean file-restore result read as a clean
+	// bill of health for data the operation did not look at, which is the sentence it exists to
+	// prevent.
 	tier2UnitNotCoveredMsg = "Az alkalmazás adatbázisa és belső kötetei nem tartoznak ebbe a visszaállításba."
+
+	// The Tier-2 UNIT restore's outcome suffix (R-102, Scenario E). The outcome names WHICH copy was
+	// just written over the app's live data — an action that overwrites must say what it overwrote
+	// with, in the sentence the customer is left holding.
+	tier2UnitRestoreSourceMsgFmt = "A visszaállítás forrása a második meghajtón lévő másolat volt (%s)."
+
+	// …and the R-101 variant. CopyLastRun is the ATTEMPT clock: it advances on a FAILED Tier-2 run
+	// too. Where no success has ever been recorded for this app, the date shown is evidence that a
+	// copy was attempted and nothing more, and the sentence must not present it as evidence of a copy.
+	tier2UnitRestoreSourceUnprovenMsgFmt = "A visszaállítás forrása a második meghajtón lévő másolat volt (%s — ez az utolsó mentési kísérlet ideje; azt nem tudjuk igazolni, hogy az sikeres volt)."
+
+	// R-102/R-103 — the DESTRUCTIVE CONFIRM, in pieces, and in Go rather than in the template.
+	//
+	// It lives here for the same reason the R-353 outcome strings do: this sentence is the only thing
+	// standing between a customer and the loss of everything they made since the copy was taken, and a
+	// silent edit to it is how a warning drifts into a reassurance. Named constants can be asserted
+	// verbatim by a test; a sentence assembled inside an HTML attribute cannot, and R-364 makes
+	// grepping accented Hungarian out of rendered markup an unreliable check on top of that.
+	//
+	// The three parts are three separate obligations:
+	//   Base      — what this action DOES: it overwrites, including the database and internal volumes.
+	//   Date      — WHICH copy it overwrites with. Two forms, because a stamp that only records an
+	//               ATTEMPT must not be presented as the date of a copy (R-101).
+	//   Contrast  — how it differs from the additive button beside it. The register's own requirement:
+	//               a destructive operation reached from a non-destructive surface must carry the
+	//               difference in the confirm, not rely on the customer inferring it from a label.
+	tier2UnitActionLabel = "Teljes visszaállítás a másolatból"
+
+	tier2UnitConfirmBase = "Ez a művelet FELÜLÍRJA az alkalmazás jelenlegi adatait – az adatbázisát és a belső köteteit is – a második meghajtón lévő másolattal. Ami a másolat óta keletkezett, elveszik."
+
+	tier2UnitConfirmDateFmt = " A másolat kelte: %s."
+
+	tier2UnitConfirmDateUnprovenFmt = " A másolat kelte: %s – ez az utolsó mentési kísérlet ideje, azt nem tudjuk igazolni, hogy sikeres volt."
+
+	tier2UnitConfirmContrast = " A mellette lévő „Fájlok visszaállítása” ezzel szemben csak a hiányzó fájlokat pótolja, és semmit nem ír felül. Az alkalmazás a művelet idejére leáll."
 )

+// tier2UnitConfirmMsg assembles the destructive confirm for one app's Tier-2 unit restore. Pure, so
+// the wording is unit-testable; the date is rendered by the SAME helper the rest of the surface uses.
+//
+// A copy with no recorded date at all still gets a confirm — it just cannot name one. Dropping the
+// whole confirm because a date is missing would remove the warning and keep the destruction.
+func tier2UnitConfirmMsg(copyDate string, proven bool) string {
+	msg := tier2UnitConfirmBase
+	if copyDate != "" {
+		if proven {
+			msg += fmt.Sprintf(tier2UnitConfirmDateFmt, fmtRFC3339Local(copyDate))
+		} else {
+			msg += fmt.Sprintf(tier2UnitConfirmDateUnprovenFmt, fmtRFC3339Local(copyDate))
+		}
+	}
+	return msg + tier2UnitConfirmContrast
+}
+
+// tier2UnitSourceMsg renders the "which copy" clause for the Tier-2 unit restore's outcome, or "" if
+// no date is recorded at all. It asks Tier2CopyDate — the SAME resolver the surface uses to pick the
+// date it puts in the confirm — so the sentence the customer approves and the sentence they are left
+// with cannot name different copies.
+func tier2UnitSourceMsg(cov backup.Tier2Coverage) string {
+	date, proven := cov.Tier2CopyDate()
+	if date == "" {
+		return ""
+	}
+	if proven {
+		return fmt.Sprintf(tier2UnitRestoreSourceMsgFmt, fmtRFC3339Local(date))
+	}
+	return fmt.Sprintf(tier2UnitRestoreSourceUnprovenMsgFmt, fmtRFC3339Local(date))
+}
+
 // backupTier2RestoreHandler (C2, closes F2) restores an app's MISSING user files in place from its
 // recorded Tier-2 copy — additive-only: existing live files are never overwritten and nothing is
 // ever deleted (see backup.RestoreTier2Files). Same handler shape as backupRestoreHandler.
@@ -1626,10 +1737,19 @@ func (s *Server) backupTier2RestoreHandler(w http.ResponseWriter, r *http.Reques
 	// about data the restore never examined, at the exact moment they pressed it BECAUSE data was
 	// missing. Only the no-coverage case is pre-flighted; every other refusal keeps its existing async
 	// path so this change cannot alter behaviour anywhere else.
+	//
+	// R-103 SPLIT THE REFUSAL IN TWO. „no files to restore" has two different answers now, and giving
+	// both customers the same sentence is what sent one of them to another page for data that is
+	// restorable on this one.
 	cov, covErr := s.backupMgr.Tier2RestoreCoverage(stackName)
 	if covErr == nil && !cov.CanRestore() {
-		s.logger.Printf("[WARN] [web] Tier-2 file restore refused up front: stack=%s has no restorable subtree in its copy (unit_present=%v) — app NOT stopped", stackName, cov.HasUnit)
-		http.Redirect(w, r, "/backups/apps?flash_error="+url.QueryEscape(tier2NoCoverageMsg), http.StatusFound)
+		msg := tier2NoCoverageMsg
+		if cov.CanRestoreUnit() {
+			msg = tier2UnitAvailableMsg
+		}
+		s.logger.Printf("[WARN] [web] Tier-2 file restore refused up front: stack=%s has no restorable subtree in its copy (unit_present=%v unit_restorable=%v) — app NOT stopped",
+			stackName, cov.HasUnit, cov.CanRestoreUnit())
+		http.Redirect(w, r, "/backups/apps?flash_error="+url.QueryEscape(msg), http.StatusFound)
 		return
 	}

@@ -1667,6 +1787,84 @@ func (s *Server) backupTier2RestoreHandler(w http.ResponseWriter, r *http.Reques
 	http.Redirect(w, r, "/backups/apps?flash="+url.QueryEscape("Fájl-visszaállítás elindult — az állapot itt frissül."), http.StatusFound)
 }

+// backupTier2UnitRestoreHandler (R-102/R-103) restores an app IN FULL from the recovery unit mirrored
+// onto the SECOND DRIVE — the app's database dumps and named-volume tars, not just its loose files.
+//
+// It is the destructive twin of backupTier2RestoreHandler above and shares its shape deliberately:
+// same guards, same single-writer refusal, same async goroutine, same status banner. What it does not
+// share is its promise. The file restore only ever ADDS what is missing; this one OVERWRITES the
+// app's live data with the copy's. The template's confirm carries that difference in words, and the
+// two actions stay two buttons for exactly that reason (§8: they are different promises).
+//
+// The pre-flight refusal is the fail-closed gate: a `recovery-unit/` directory that exists is not a
+// package. Refusing here means the app is never stopped for a mirror that could not have been read.
+func (s *Server) backupTier2UnitRestoreHandler(w http.ResponseWriter, r *http.Request) {
+	_ = r.ParseForm()
+	stackName := r.FormValue("stack_name")
+
+	if stackName == "" {
+		http.Redirect(w, r, "/backups/apps?flash_error=Hi%C3%A1nyz%C3%B3+param%C3%A9terek", http.StatusFound)
+		return
+	}
+	// Same F2-defense as both restores beside it: a stack name is a single segment, never a path.
+	if !validStackName(stackName) {
+		s.logger.Printf("[WARN] [web] Tier-2 unit restore rejected: invalid stack_name %q from %s", stackName, r.RemoteAddr)
+		http.Redirect(w, r, "/backups/apps?flash_error=%C3%89rv%C3%A9nytelen+alkalmaz%C3%A1sn%C3%A9v", http.StatusFound)
+		return
+	}
+	if s.backupMgr == nil {
+		http.Redirect(w, r, "/backups/apps?flash_error=Ment%C3%A9s+nincs+be%C3%A1ll%C3%ADtva", http.StatusFound)
+		return
+	}
+	// R-351b (Scenario H): a second press — by button or by a direct POST — must not start a second
+	// run. restoreOpBlocked() and not IsRunning(), because the concurrency flag is only taken inside
+	// the goroutine, after this handler has already returned.
+	if msg, blocked := s.restoreOpBlocked(); blocked {
+		http.Redirect(w, r, "/backups/apps?flash_error="+url.QueryEscape(msg), http.StatusFound)
+		return
+	}
+
+	// Pre-flight, before any op is begun and before the app is stopped: does this copy hold a unit
+	// this restore can actually open? Only the no-unit case is pre-flighted; every other refusal keeps
+	// its existing async path, so this cannot alter behaviour anywhere else.
+	cov, covErr := s.backupMgr.Tier2RestoreCoverage(stackName)
+	if covErr != nil {
+		s.logger.Printf("[WARN] [web] Tier-2 unit restore refused up front: stack=%s: %v — app NOT stopped", stackName, covErr)
+		http.Redirect(w, r, "/backups/apps?flash_error="+url.QueryEscape(covErr.Error()), http.StatusFound)
+		return
+	}
+	if !cov.CanRestoreUnit() {
+		s.logger.Printf("[WARN] [web] Tier-2 unit restore refused up front: stack=%s has no openable unit in its copy (unit_present=%v) — app NOT stopped", stackName, cov.HasUnit)
+		http.Redirect(w, r, "/backups/apps?flash_error="+url.QueryEscape(tier2NoCoverageMsg), http.StatusFound)
+		return
+	}
+
+	s.logger.Printf("[WARN] [web] Tier-2 UNIT restore requested (async, OVERWRITES live data): stack=%s from %s", stackName, r.RemoteAddr)
+	s.backupMgr.BeginRestoreOp("tier2-unit-restore", stackName)
+	go func() {
+		start := time.Now()
+		res, err := s.backupMgr.RestoreTier2Unit(stackName)
+		if err != nil {
+			s.logger.Printf("[ERROR] [web] Tier-2 unit restore failed (async): stack=%s: %v", stackName, err)
+			s.backupMgr.EndRestoreOp(false, "Teljes visszaállítás sikertelen: "+err.Error())
+			return
+		}
+		s.logger.Printf("[INFO] [web] Tier-2 unit restore completed (async): stack=%s in %s (volumes %d/%d, dbs %d/%d)",
+			stackName, time.Since(start), res.VolumesReplayed, res.ManifestVolumes, res.DBsReplayed, res.ManifestDBs)
+		// The outcome sentence is yesterday's — unitRestoreOutcomeMsg, unchanged, because what came
+		// back is the same fact whichever unit it came out of, and a second wording of it would be a
+		// second thing to keep honest. What IS added is which copy it came from and how old that copy
+		// is: this action overwrote the customer's live data, and the sentence they are left with has
+		// to say what it overwrote it with (Scenario E).
+		msg := unitRestoreOutcomeMsg(stackName, res)
+		if src := tier2UnitSourceMsg(cov); src != "" {
+			msg += " " + src
+		}
+		s.backupMgr.EndRestoreOp(true, msg)
+	}()
+	http.Redirect(w, r, "/backups/apps?flash="+url.QueryEscape("Teljes visszaállítás elindult — az állapot itt frissül."), http.StatusFound)
+}
+
 // settingsBaseData is the shared identity block used by every settings-family subpage
 // (D1 split: /settings, /settings/notifications, /settings/security, /storage).
 func (s *Server) settingsBaseData(page, title string) map[string]interface{} {
@@ -0,0 +1,413 @@
+package web
+
+import (
+	"io"
+	"log"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+
+	"gitea.dooplex.hu/admin/felhom-controller/internal/backup"
+	"gitea.dooplex.hu/admin/felhom-controller/internal/config"
+	"gitea.dooplex.hu/admin/felhom-controller/internal/settings"
+)
+
+// R-103 Group D — the surface: the refusal becomes an action.
+//
+// Before v0.229.0 an app whose Tier-2 copy held only a recovery unit got a message telling it to
+// press a button on a DIFFERENT page. The data it was asking for is in the copy it is looking at, and
+// since R-102 it is restorable from there. The action now lives where the refusal was.
+//
+// Every string assertion here compares against the NAMED CONSTANT rather than a Hungarian literal
+// retyped in the test. That is R-364 discipline in its strongest form: a grep for accented text
+// returned zero for strings that were present, and a re-typed literal can differ from the shipped one
+// by a character nobody sees.
+
+// --- the surface (template) -----------------------------------------------------------------
+
+// r103Row is a Tier-2-configured row with a successful copy — the shape the template needs before it
+// will render the actions block at all.
+func r103Row(unitRestorable bool, date string, proven bool) AppBackupRow {
+	row := AppBackupRow{
+		StackName: "docmost", DisplayName: "Docmost",
+		Tier2Configured: true, Tier2Dest: "flash", Tier2Schedule: "Naponta",
+		Tier2LastRun: date, Tier2LastStatus: "ok", Tier2StatusBadge: "Sikeres",
+		Tier2LastSuccess: date, Tier2SuccessTracked: true,
+		Tier2UnitRestorable: unitRestorable,
+	}
+	if unitRestorable {
+		row.Tier2CopyDate, row.Tier2CopyDateProven = date, proven
+		row.Tier2UnitConfirm = tier2UnitConfirmMsg(date, proven)
+	}
+	return row
+}
+
+// D1 — TestR103_UnitActionOfferedWhenTheMirrorExists.
+func TestR103_UnitActionOfferedWhenTheMirrorExists(t *testing.T) {
+	html := renderBackupPage(t, "backups_apps", baseBackupData([]AppBackupRow{
+		r103Row(true, "2026-08-25T03:30:00Z", true),
+	}))
+	if !strings.Contains(html, `action="/backup/tier2/unit-restore"`) {
+		t.Error("the unit-restore form is not on the page — the refusal is still a dead end")
+	}
+	if !strings.Contains(html, tier2UnitActionLabel) {
+		t.Errorf("the action is not labelled %q", tier2UnitActionLabel)
+	}
+	// The additive action must still be there, separately. Merging them is forbidden: they are
+	// different promises (one adds, one overwrites).
+	if !strings.Contains(html, `action="/backup/tier2/restore"`) {
+		t.Error("the additive file restore disappeared from the row")
+	}
+	// The destructive one is visually distinct from the additive one beside it.
+	if !strings.Contains(html, "btn-danger-outline") {
+		t.Error("the destructive action does not carry a danger style")
+	}
+}
+
+// D2 — TestR103_UnitActionAbsentWhenItDoesNot. Scenario G: no legs and no openable unit → an honest
+// refusal, and NO unit action. A button offered over a copy the restore would refuse is worse than no
+// button, because it is a promise withdrawn at the moment of use.
+func TestR103_UnitActionAbsentWhenItDoesNot(t *testing.T) {
+	html := renderBackupPage(t, "backups_apps", baseBackupData([]AppBackupRow{
+		r103Row(false, "2026-08-25T03:30:00Z", true),
+	}))
+	if strings.Contains(html, "/backup/tier2/unit-restore") {
+		t.Error("the unit action was offered for a copy with no openable unit")
+	}
+	if strings.Contains(html, tier2UnitActionLabel) {
+		t.Error("the unit action's label leaked onto a row that must not offer it")
+	}
+	// NEGATIVE CONTROL for D1's assertions: the row itself did render, so D1's positives were not
+	// an artefact of the whole block being absent.
+	if !strings.Contains(html, `action="/backup/tier2/restore"`) {
+		t.Fatal("the row did not render at all — D1's positive assertions prove nothing")
+	}
+}
+
+// D3 — TestR103_ConfirmStatesTheOverwrite. The confirm must carry the DIFFERENCE the register
+// requires: a destructive operation reached from a non-destructive surface says so, and says how it
+// differs from the action beside it.
+func TestR103_ConfirmStatesTheOverwrite(t *testing.T) {
+	confirm := tier2UnitConfirmMsg("2026-08-25T03:30:00Z", true)
+
+	if !strings.Contains(confirm, tier2UnitConfirmBase) {
+		t.Error("the confirm does not state that the operation OVERWRITES live data")
+	}
+	if !strings.Contains(confirm, tier2UnitConfirmContrast) {
+		t.Error("the confirm does not state how it differs from the additive restore beside it")
+	}
+	// NEGATIVE CONTROL: the additive restore's own confirm must NOT have acquired this language.
+	// Without it, a test that passed because both buttons warn about overwriting would look green.
+	html := renderBackupPage(t, "backups_apps", baseBackupData([]AppBackupRow{
+		r103Row(true, "2026-08-25T03:30:00Z", true),
+	}))
+	fileConfirmStart := strings.Index(html, "Visszaállítja a hiányzó fájlokat")
+	if fileConfirmStart < 0 {
+		t.Fatal("the additive confirm is gone — the negative control has nothing to check")
+	}
+	fileConfirm := html[fileConfirmStart:]
+	if end := strings.Index(fileConfirm, `">`); end > 0 {
+		fileConfirm = fileConfirm[:end]
+	}
+	if strings.Contains(fileConfirm, "FEL") {
+		t.Errorf("the ADDITIVE confirm gained overwrite language: %q", fileConfirm)
+	}
+	// And the confirm reaches the markup as the rendered attribute, not only as a Go constant.
+	if !strings.Contains(html, `data-confirm=`) {
+		t.Error("no data-confirm attribute rendered")
+	}
+	if !strings.Contains(html, "FEL") {
+		t.Error("the destructive wording never reached the page")
+	}
+}
+
+// D4 — TestR103_ConfirmNamesTheCopyDate. Scenario E. The action overwrites live data with a copy of a
+// certain age, and „nobody restores last week over today by accident" is only true if the date is on
+// the screen. R-101 governs the wording when the date is an ATTEMPT rather than a proven copy.
+func TestR103_ConfirmNamesTheCopyDate(t *testing.T) {
+	const stamp = "2026-08-25T03:30:00Z"
+	rendered := fmtRFC3339Local(stamp)
+	if rendered == stamp {
+		t.Fatal("the stamp did not render as a local date — the assertion below would be vacuous")
+	}
+
+	proven := tier2UnitConfirmMsg(stamp, true)
+	if !strings.Contains(proven, rendered) {
+		t.Errorf("the confirm does not name the copy's date: %q", proven)
+	}
+	unproven := tier2UnitConfirmMsg(stamp, false)
+	if !strings.Contains(unproven, rendered) {
+		t.Errorf("the unproven confirm does not name the date: %q", unproven)
+	}
+	if proven == unproven {
+		t.Error("a proven copy and a bare attempt got the SAME sentence — R-101 exactly")
+	}
+	// A copy with no recorded date still gets the warning; it just cannot name one.
+	none := tier2UnitConfirmMsg("", false)
+	if !strings.Contains(none, tier2UnitConfirmBase) || !strings.Contains(none, tier2UnitConfirmContrast) {
+		t.Errorf("a dateless copy lost its confirm entirely: %q", none)
+	}
+
+	// And it is on the page, not merely constructible.
+	html := renderBackupPage(t, "backups_apps", baseBackupData([]AppBackupRow{r103Row(true, stamp, true)}))
+	if !strings.Contains(html, rendered) {
+		t.Errorf("the copy's date %q is not in the rendered row", rendered)
+	}
+}
+
+// TestR103_AvailableMsgNamesTheButtonByItsLabel — the refusal that now points AT the new action must
+// name it by the label the button actually carries, or it points at nothing.
+func TestR103_AvailableMsgNamesTheButtonByItsLabel(t *testing.T) {
+	if !strings.Contains(tier2UnitAvailableMsg, tier2UnitActionLabel) {
+		t.Errorf("tier2UnitAvailableMsg does not name %q", tier2UnitActionLabel)
+	}
+	// It must NOT send anyone to another page any more; that is the R-103 defect it replaces.
+	if strings.Contains(tier2UnitAvailableMsg, "oldalon") {
+		t.Error("the message still routes the customer to another page for a copy restorable here")
+	}
+	// The surviving no-coverage message still names the route that works.
+	if !strings.Contains(tier2NoCoverageMsg, "oldalon") {
+		t.Error("tier2NoCoverageMsg no longer names any route — Scenario G requires one")
+	}
+	// C3 — tier2UnitNotCoveredMsg is NOT deleted: it is still appended where the FILE restore ran.
+	if tier2UnitNotCoveredMsg == "" {
+		t.Fatal("tier2UnitNotCoveredMsg was deleted")
+	}
+	if !strings.Contains(readSourceFile(t, "handlers.go"), `msg += " " + tier2UnitNotCoveredMsg`) {
+		t.Error("tier2UnitNotCoveredMsg is no longer appended by the file-restore handler")
+	}
+}
+
+func readSourceFile(t *testing.T, name string) string {
+	t.Helper()
+	b, err := os.ReadFile(name)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return string(b)
+}
+
+// --- the handler ----------------------------------------------------------------------------
+
+// r103Provider is a StackDataProvider that completes every lifecycle call, so the restore goroutine
+// runs to its outcome instead of parking.
+type r103Provider struct{ hdd string }
+
+func (p *r103Provider) GetStackComposePath(string) (string, bool) { return "", false }
+func (p *r103Provider) ListDeployedStacks() []backup.StackSummary { return nil }
+func (p *r103Provider) GetStackHDDMounts(string) []string         { return nil }
+func (p *r103Provider) GetStackHDDPath(string) string             { return p.hdd }
+func (p *r103Provider) GetImportRoot() string                     { return "" }
+func (p *r103Provider) GetDockerVolumes(string) []string          { return nil }
+func (p *r103Provider) StopStack(string) error                    { return nil }
+func (p *r103Provider) StartStack(string) error                   { return nil }
+func (p *r103Provider) RefreshAndIsRunning(string) bool           { return true }
+func (p *r103Provider) GetStackRecoveryInfo(string) (backup.RecoveryInfo, bool) {
+	return backup.RecoveryInfo{}, false
+}
+func (p *r103Provider) GetStackClassifiedBinds(string) ([]backup.ClassifiedBind, bool) {
+	return nil, false
+}
+func (p *r103Provider) RecoverStackSecrets(string, []string) map[string]string { return nil }
+func (p *r103Provider) RecreateStackDefinitionFromUnit(string, string, map[string]string) error {
+	return nil
+}
+func (p *r103Provider) StartStackServices(string, []string) error { return nil }
+
+const r103CopyStamp = "2026-08-25T03:30:00Z"
+
+// newR103Server wires a Server over a real backup.Manager whose recorded Tier-2 copy for "app" holds
+// an OPENABLE recovery unit mirror. Nothing is stubbed between the handler and the manager: the whole
+// point of D6 is that the wiring is what is under test.
+func newR103Server(t *testing.T, withUnit bool) (*Server, *backup.Manager) {
+	t.Helper()
+	tmp := t.TempDir()
+	live := filepath.Join(tmp, "usb")
+	dest := filepath.Join(tmp, "flash")
+	lg := log.New(io.Discard, "", 0)
+	sett, err := settings.Load(filepath.Join(tmp, "settings.json"), lg)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, p := range []string{live, dest} {
+		if err := sett.AddStoragePath(settings.StoragePath{Path: p, Label: filepath.Base(p)}); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if err := sett.SetCrossDriveConfig("app", &settings.CrossDriveBackup{
+		Enabled: true, Method: "rsync", DestinationPath: dest,
+		LastRun: r103CopyStamp, LastSuccess: r103CopyStamp, SuccessTracked: true, LastStatus: "ok",
+	}); err != nil {
+		t.Fatal(err)
+	}
+	destBase := filepath.Join(dest, "backups", "secondary", "app")
+	write := func(rel, body string) {
+		p := filepath.Join(destBase, rel)
+		if err := os.MkdirAll(filepath.Dir(p), 0o755); err != nil {
+			t.Fatal(err)
+		}
+		if err := os.WriteFile(p, []byte(body), 0o644); err != nil {
+			t.Fatal(err)
+		}
+	}
+	write(".felhom-tier2-layout", "2")
+	if withUnit {
+		write("recovery-unit/manifest.json", `{"schema_version":1,"app_name":"app"}`)
+		write("recovery-unit/compose/app.yaml", "deployed: true\nenv:\n  SUBDOMAIN: app\n")
+		write("recovery-unit/compose/docker-compose.yml", "services:\n  app:\n    image: example/app:1\n")
+	} else {
+		// A directory that exists and is not a package — the fail-closed case.
+		if err := os.MkdirAll(filepath.Join(destBase, "recovery-unit"), 0o755); err != nil {
+			t.Fatal(err)
+		}
+	}
+	cfg := &config.Config{}
+	cfg.Paths.DataDir = tmp
+	m := backup.NewManager(cfg, sett, lg)
+	m.SetStackProvider(&r103Provider{hdd: live})
+	return &Server{cfg: cfg, backupMgr: m, logger: lg}, m
+}
+
+func postTier2UnitRestore(t *testing.T, s *Server, stack string) *httptest.ResponseRecorder {
+	t.Helper()
+	form := url.Values{"stack_name": {stack}}
+	req := httptest.NewRequest(http.MethodPost, "/backup/tier2/unit-restore", strings.NewReader(form.Encode()))
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	rec := httptest.NewRecorder()
+	s.backupTier2UnitRestoreHandler(rec, req)
+	return rec
+}
+
+func waitRestoreDone(t *testing.T, m *backup.Manager) backup.RestoreOpStatus {
+	t.Helper()
+	deadline := time.Now().Add(30 * time.Second)
+	for time.Now().Before(deadline) {
+		st := m.RestoreStatus()
+		if !st.Running && st.Last != nil {
+			return st
+		}
+		time.Sleep(50 * time.Millisecond)
+	}
+	t.Fatal("the restore never published a result")
+	return backup.RestoreOpStatus{}
+}
+
+// D5 — TestR103_SecondPressIsRefused. Scenario H, R-351b. The concurrency flag is only taken inside
+// the goroutine, AFTER the handler returns, so a guard reading IsRunning() alone leaves a window in
+// which a second press starts a second run and is told „elindult".
+func TestR103_SecondPressIsRefused(t *testing.T) {
+	s, m := newR103Server(t, true)
+	m.BeginRestoreOp("restore", "other-app") // a restore is already in flight, display-flag set
+
+	rec := postTier2UnitRestore(t, s, "app")
+	loc := rec.Header().Get("Location")
+	if !strings.Contains(loc, "flash_error") {
+		t.Fatalf("a second press was accepted: %q", loc)
+	}
+	// The identity of the FIRST operation survives — the consequence, not which flag was read.
+	if st := m.RestoreStatus(); st.Stack != "other-app" {
+		t.Errorf("the in-flight op was replaced by the refused one: %+v", st)
+	}
+}
+
+// D6 — TestR103_HandlerPublishesTheOutcome. THE SEAM TEST.
+//
+// It reads the outcome off RestoreStatus().Last.Message — the only place a customer sees it — rather
+// than calling the manager and inspecting a return value. Three shipped defects in this project came
+// from testing a component whose caller never invoked it (R-106's fakeObserver being the clearest),
+// and the mechanism here is exactly that shape: a correct RestoreTier2Unit wired to nothing would
+// leave the banner silent and every manager-level test green.
+//
+// Red-proof (recorded in REPORT.md): drop the `s.backupMgr.EndRestoreOp(true, msg)` call at the end
+// of the handler's goroutine → this test fails on "the restore never published a result".
+func TestR103_HandlerPublishesTheOutcome(t *testing.T) {
+	s, m := newR103Server(t, true)
+
+	rec := postTier2UnitRestore(t, s, "app")
+	if rec.Code != http.StatusFound {
+		t.Fatalf("status = %d, want 302", rec.Code)
+	}
+	if loc := rec.Header().Get("Location"); strings.Contains(loc, "flash_error") {
+		t.Fatalf("the restore was refused: %q", loc)
+	}
+
+	st := waitRestoreDone(t, m)
+	if !st.Last.OK {
+		t.Fatalf("outcome reported failure: %q", st.Last.Message)
+	}
+	if st.Last.Stack != "app" || st.Last.Op != "tier2-unit-restore" {
+		t.Errorf("the published result names the wrong operation: op=%q stack=%q", st.Last.Op, st.Last.Stack)
+	}
+	// The sentence is yesterday's honest outcome PLUS the clause naming which copy overwrote the live
+	// data (Scenario E). Asserted as an exact composition so neither half can silently vanish.
+	wantOutcome := unitRestoreOutcomeMsg("app", backup.UnitRestoreResult{})
+	wantSource := tier2UnitSourceMsg(backup.Tier2Coverage{CopyLastSuccess: r103CopyStamp})
+	if wantSource == "" {
+		t.Fatal("the fixture recorded no copy date — the assertion below would be vacuous")
+	}
+	if want := wantOutcome + " " + wantSource; st.Last.Message != want {
+		t.Errorf("published message =\n  %q\nwant\n  %q", st.Last.Message, want)
+	}
+	if !strings.Contains(st.Last.Message, fmtRFC3339Local(r103CopyStamp)) {
+		t.Error("the outcome does not name the date of the copy it restored from")
+	}
+}
+
+// TestR103_UnitRestoreRefusesAnUnopenableMirrorWithoutStopping — the handler's fail-closed pre-flight.
+// A directory is not a package, and refusing before BeginRestoreOp means no banner, no outage and no
+// rewritten definition.
+func TestR103_UnitRestoreRefusesAnUnopenableMirrorWithoutStopping(t *testing.T) {
+	s, m := newR103Server(t, false)
+
+	rec := postTier2UnitRestore(t, s, "app")
+	loc := rec.Header().Get("Location")
+	if !strings.Contains(loc, "flash_error") {
+		t.Fatalf("the restore was accepted over an unopenable mirror: %q", loc)
+	}
+	if !strings.Contains(loc, url.QueryEscape(tier2NoCoverageMsg)) {
+		t.Errorf("refusal flash = %q, want tier2NoCoverageMsg", loc)
+	}
+	if st := m.RestoreStatus(); st.Running || st.Last != nil {
+		t.Errorf("an operation was begun despite the refusal: %+v", st)
+	}
+}
+
+// TestR103_UnitRestoreHandlerGuards — the same three guards the two restores beside it carry, proven
+// to run BEFORE any work (backupMgr is nil, so reaching it would panic).
+func TestR103_UnitRestoreHandlerGuards(t *testing.T) {
+	s := &Server{logger: log.New(io.Discard, "", 0)} // backupMgr nil on purpose
+	for name, want := range map[string]string{
+		"../../etc": "%C3%89rv%C3%A9nytelen+alkalmaz%C3%A1sn%C3%A9v",
+		"a/b":       "%C3%89rv%C3%A9nytelen+alkalmaz%C3%A1sn%C3%A9v",
+		"":          "Hi%C3%A1nyz%C3%B3+param%C3%A9terek",
+	} {
+		rec := postTier2UnitRestore(t, s, name)
+		if loc := rec.Header().Get("Location"); !strings.Contains(loc, want) {
+			t.Errorf("%q: redirect = %q, want flash %q", name, loc, want)
+		}
+	}
+	rec := postTier2UnitRestore(t, s, "docmost")
+	if loc := rec.Header().Get("Location"); !strings.Contains(loc, "Ment%C3%A9s+nincs+be%C3%A1ll%C3%ADtva") {
+		t.Errorf("nil backupMgr: redirect = %q", loc)
+	}
+}
+
+// TestR103_FileRestoreRefusalPointsAtTheActionThatWorks — the R-103 split. An app with no file legs
+// but a restorable unit gets the message that names the button beside it, NOT the one that sends it
+// to another page.
+func TestR103_FileRestoreRefusalPointsAtTheActionThatWorks(t *testing.T) {
+	s, _ := newR103Server(t, true)
+	rec := postTier2Restore(t, s, "app")
+	loc := rec.Header().Get("Location")
+	if !strings.Contains(loc, url.QueryEscape(tier2UnitAvailableMsg)) {
+		t.Errorf("refusal flash = %q, want tier2UnitAvailableMsg", loc)
+	}
+	if strings.Contains(loc, url.QueryEscape(tier2NoCoverageMsg)) {
+		t.Error("the old dead-end message is still shown for a copy restorable here")
+	}
+}
@@ -537,6 +537,10 @@ func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	// C2: in-place, additive-only file restore from the Tier-2 copy (class-C user files)
 	case path == "/backup/tier2/restore" && r.Method == http.MethodPost:
 		s.backupTier2RestoreHandler(w, r)
+	// R-102/R-103: the DESTRUCTIVE twin — a full recovery-unit restore read from the SECOND DRIVE's
+	// mirror. Separate route because it is a separate promise: this one overwrites live data.
+	case path == "/backup/tier2/unit-restore" && r.Method == http.MethodPost:
+		s.backupTier2UnitRestoreHandler(w, r)
 	// Off-box (NAS) restic-SFTP backup (Part B)
 	case path == "/backup/offbox/config" && r.Method == http.MethodPost:
 		s.offboxConfigHandler(w, r)
@@ -261,6 +261,17 @@
                            {{else}}
                            <span class="layer-reason" style="opacity:.85">Még nincs sikeres másolat, amiből vissza lehetne állítani.</span>
                            {{end}}
+                            {{/* R-102/R-103: the DESTRUCTIVE twin of the button above. Offered only when the
+                                 copy holds an openable recovery unit (Tier2UnitRestorable — a second
+                                 predicate, never a widening of the file restore's). It is deliberately a
+                                 SEPARATE button in a danger style: the one beside it only adds what is
+                                 missing, this one overwrites the app's live data with the copy's. */}}
+                            {{if .Tier2UnitRestorable}}
+                            <form method="POST" action="/backup/tier2/unit-restore" style="display:inline">{{$.CSRFField}}
+                                <input type="hidden" name="stack_name" value="{{.StackName}}">
+                                <button type="submit" class="btn btn-xs btn-danger-outline" data-confirm="{{.Tier2UnitConfirm}}">Teljes visszaállítás a másolatból</button>
+                            </form>
+                            {{end}}
                            <a href="/stacks/{{.StackName}}/backup" class="btn btn-xs btn-outline">Beállítás</a>
                        </div>
                    {{else}}