Phase 5 hygiene: image ownership, real deletes, scan resilience

Images were readable by any signed-in user, not just their owner. Keys
are now namespaced per user in both shapes the app writes, the three
bar/ objects that predated that were migrated under the owner's prefix,
and the image route enforces the prefix - answering 404 rather than 403
so it does not confirm someone else's key exists. Barcode-mirrored
images now write under the user prefix too.

deleteImage existed but was never called, so deleting a drink, bar item
or scan removed the row and left the file in storage forever, still
fetchable. All three now clean up through one shared helper, after the
database work and best-effort, so a storage hiccup cannot block a delete
the user asked for or leave the row behind.

Menu scans are processed detached from the request, so every deploy
abandoned anything in flight and left the row PROCESSING forever with a
spinner that never resolved. They are now reaped lazily when a user
lists their scans - no scheduler needed. Concurrent extractions are
capped at two per process: each is a vision call with a four minute
timeout that costs real money, and nothing else bounded them.

MenuItem gains userId. Ownership was only ever transitive via scanId,
which held because nothing queries MenuItem directly, but left any
future direct query an IDOR with nothing to stop it.

Restore was correctly scoped but unbounded, so a crafted file could
create unlimited rows in one transaction against shared Postgres - self
harm with one user, denial of service with several. Capped, and imageUrl
from the CSV now goes through the same validation the API enforces
instead of reaching the column unchecked.

Members can delete their own account and data. Once the app holds other
people's history, including Rating.location, that is the minimum.

Registration rate limiting took the first x-forwarded-for hop, which the
client controls; it now takes the last, which our proxy appends.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

prisma/schema.prisma

@@ -279,6 +279,11 @@ model MenuScan {
 
 model MenuItem {
   id             String    @id @default(cuid())
+  // Denormalised from MenuScan. Ownership was only ever transitive via scanId, which
+  // worked because nothing queries MenuItem directly - but left any future direct
+  // query an IDOR with nothing to stop it. Nullable only for rows created before
+  // this column existed; every write sets it.
+  userId         String?
   scanId         String
   name           String
   type           DrinkType
@@ -297,6 +302,7 @@ model MenuItem {
   matchedDrink Drink?   @relation(fields: [matchedDrinkId], references: [id], onDelete: SetNull)
 
   @@index([scanId])
+  @@index([userId])
 }
 
 // ─── Wishlist / Try Later ────────────────────────────────────────

src/app/api/admin/users/[id]/route.ts

@@ -2,7 +2,7 @@ import { NextResponse } from "next/server"
 import { z } from "zod"
 import { requireOwner } from "@/lib/authz"
 import { prisma } from "@/lib/prisma"
-import { deleteImage } from "@/lib/s3"
+import { deleteImagesByUrl } from "@/lib/images"
 import { revokeGatewayKey } from "@/lib/ai/switchboard-keys"
 
 const patchSchema = z.object({
@@ -91,23 +91,19 @@ export async function DELETE(
 
   // Best effort after the fact: never let storage or the gateway block a deletion
   // the user asked for, and never leave the account half-deleted.
-  const keyPrefix = "/minio-images/"
+  const urls = [...drinks, ...barItems, ...scans].map((r) => r.imageUrl)
-  const objectKeys = [...drinks, ...barItems, ...scans]
+  const gatewayKeyIds = keys
-    .map((r) => r.imageUrl)
+    .map((k) => k.gatewayKeyId)
-    .filter((u): u is string => !!u && u.startsWith(keyPrefix))
+    .filter((id): id is string => !!id)
-    .map((u) => u.slice(keyPrefix.length))
 
-  await Promise.allSettled([
+  const [imagesDeleted] = await Promise.all([
-    ...objectKeys.map((k) => deleteImage(k)),
+    deleteImagesByUrl(urls),
-    ...keys
+    Promise.allSettled(gatewayKeyIds.map((id) => revokeGatewayKey(id))),
-      .map((k) => k.gatewayKeyId)
-      .filter((id): id is string => !!id)
-      .map((id) => revokeGatewayKey(id)),
   ])
 
   return NextResponse.json({
     success: true,
-    imagesDeleted: objectKeys.length,
+    imagesDeleted,
-    gatewayKeysRevoked: keys.filter((k) => k.gatewayKeyId).length,
+    gatewayKeysRevoked: gatewayKeyIds.length,
   })
 }

src/app/api/auth/register/route.ts

@@ -26,9 +26,13 @@ const registerSchema = z.object({
 
 export async function POST(request: Request) {
   try {
-    // Rate limit: 5 registration attempts per IP per minute
+    // Rate limit: 5 registration attempts per IP per minute.
+    // Take the LAST hop, not the first: everything before it is client-supplied and
+    // can be forged to get a fresh bucket per request. The last entry is the one our
+    // own reverse proxy appended.
     const forwarded = request.headers.get("x-forwarded-for")
-    const ip = forwarded?.split(",")[0]?.trim() ?? "unknown"
+    const hops = forwarded?.split(",").map((h) => h.trim()).filter(Boolean) ?? []
+    const ip = hops.length > 0 ? hops[hops.length - 1] : "unknown"
     const rl = rateLimit(`register:${ip}`, 5, 60 * 1000)
     if (!rl.success) {
       return NextResponse.json(

src/app/api/bar/[id]/route.ts

@@ -1,6 +1,7 @@
 import { NextRequest, NextResponse } from "next/server"
 import { auth } from "@/lib/auth"
 import { prisma } from "@/lib/prisma"
+import { deleteImagesByUrl } from "@/lib/images"
 import { barItemUpdateSchema } from "@/lib/validators"
 
 export async function PUT(
@@ -65,7 +66,7 @@ export async function DELETE(
     // Check ownership
     const existing = await prisma.barItem.findUnique({
       where: { id: params.id },
-      select: { userId: true },
+      select: { userId: true, imageUrl: true },
     })
 
     if (!existing) {
@@ -80,6 +81,9 @@ export async function DELETE(
       where: { id: params.id },
     })
 
+    // After the row is gone, so a storage hiccup cannot block the delete.
+    void deleteImagesByUrl([existing.imageUrl])
+
     return NextResponse.json({ success: true })
   } catch (error) {
     console.error("DELETE /api/bar/[id] error:", error)

src/app/api/bar/barcode-lookup/route.ts

@@ -29,7 +29,7 @@ function mapOffCategoryToDrinkType(tags: string[]): string | null {
   return null
 }
 
-async function lookupOpenFoodFacts(barcode: string) {
+async function lookupOpenFoodFacts(barcode: string, userId: string) {
   try {
     const res = await fetch(
       `https://world.openfoodfacts.org/api/v2/product/${barcode}.json`,
@@ -48,8 +48,9 @@ async function lookupOpenFoodFacts(barcode: string) {
     // item with no image beats one with an image that cannot render.
     const remoteImage =
       product.image_url || product.image_front_url || product.image_front_small_url || null
+    // Namespaced by user so the image route can enforce ownership by key prefix.
     const imageUrl = remoteImage
-      ? await mirrorExternalImage(remoteImage, `bar/${barcode}`)
+      ? await mirrorExternalImage(remoteImage, `${userId}/bar/${barcode}`)
       : null
 
     // Extract ABV from alcohol_100g nutrient or nutriments
@@ -153,7 +154,7 @@ export async function POST(request: Request) {
     }
 
     // Try Open Food Facts first
-    const offResult = await lookupOpenFoodFacts(barcode)
+    const offResult = await lookupOpenFoodFacts(barcode, session.user.id)
     if (offResult) {
       return NextResponse.json({ ...offResult, barcode, source: "openfoodfacts" })
     }

src/app/api/drinks/[id]/route.ts

@@ -1,6 +1,7 @@
 import { NextRequest, NextResponse } from "next/server"
 import { auth } from "@/lib/auth"
 import { prisma } from "@/lib/prisma"
+import { deleteImagesByUrl } from "@/lib/images"
 import { drinkUpdateSchema } from "@/lib/validators"
 
 export async function GET(
@@ -113,7 +114,7 @@ export async function DELETE(
     // Check ownership
     const existing = await prisma.drink.findUnique({
       where: { id: params.id },
-      select: { userId: true },
+      select: { userId: true, imageUrl: true },
     })
 
     if (!existing) {
@@ -128,6 +129,9 @@ export async function DELETE(
       where: { id: params.id },
     })
 
+    // After the row is gone, so a storage hiccup cannot block the delete.
+    void deleteImagesByUrl([existing.imageUrl])
+
     return NextResponse.json({ success: true })
   } catch (error) {
     console.error("DELETE /api/drinks/[id] error:", error)

src/app/api/scan/[id]/route.ts

@@ -1,6 +1,7 @@
 import { NextResponse } from "next/server"
 import { auth } from "@/lib/auth"
 import { prisma } from "@/lib/prisma"
+import { deleteImagesByUrl } from "@/lib/images"
 
 export async function GET(
   request: Request,
@@ -61,5 +62,8 @@ export async function DELETE(
 
   await prisma.menuScan.delete({ where: { id: params.id } })
 
+  // After the row is gone, so a storage hiccup cannot block the delete.
+  void deleteImagesByUrl([scan.imageUrl])
+
   return NextResponse.json({ success: true })
 }

src/app/api/scan/route.ts

@@ -4,6 +4,11 @@ import { prisma } from "@/lib/prisma"
 import { uploadImage } from "@/lib/s3"
 import { rateLimit } from "@/lib/rate-limit"
 import { randomUUID } from "crypto"
+import {
+  reapStuckScans,
+  tryAcquireScanSlot,
+  releaseScanSlot,
+} from "@/lib/scan-health"
 
 export async function GET(request: Request) {
   const session = await auth()
@@ -11,6 +16,10 @@ export async function GET(request: Request) {
     return NextResponse.json({ error: "Unauthorized" }, { status: 401 })
   }
 
+  // Lazy housekeeping: a deploy abandons in-flight scans and there is no queue to
+  // recover them, so mark the stale ones failed before listing.
+  await reapStuckScans(session.user.id)
+
   const { searchParams } = new URL(request.url)
   const page = parseInt(searchParams.get("page") || "1")
   const limit = parseInt(searchParams.get("limit") || "20")
@@ -82,10 +91,26 @@ export async function POST(request: Request) {
       },
     })
 
+    if (!tryAcquireScanSlot()) {
+      // Fail fast rather than piling vision calls onto a busy process. The row is
+      // already created, so the user sees why instead of an endless spinner.
+      await prisma.menuScan.update({
+        where: { id: scan.id },
+        data: {
+          status: "FAILED",
+          errorMessage: "Too many scans are being processed right now. Please try again in a moment.",
+        },
+      })
+      return NextResponse.json(
+        { error: "Busy processing other scans. Please try again in a moment." },
+        { status: 503 }
+      )
+    }
+
     // Kick off async processing - don't await
-    processMenuScan(scan.id, buffer, file.type, session.user.id).catch(
+    processMenuScan(scan.id, buffer, file.type, session.user.id)
-      (error) => console.error("Scan processing error:", error)
+      .catch((error) => console.error("Scan processing error:", error))
-    )
+      .finally(releaseScanSlot)
 
     return NextResponse.json(scan, { status: 201 })
   } catch (error) {
@@ -138,6 +163,7 @@ async function processMenuScan(
 
       return {
         scanId,
+        userId,
         name: item.name,
         type: item.type,
         subType: item.subType,

src/app/api/settings/account/route.ts

@@ -0,0 +1,62 @@
+import { NextResponse } from "next/server"
+import { requireUser } from "@/lib/authz"
+import { prisma } from "@/lib/prisma"
+import { deleteImagesByUrl } from "@/lib/images"
+import { revokeGatewayKey } from "@/lib/ai/switchboard-keys"
+
+/**
+ * Self-service account deletion.
+ *
+ * Once the app holds other people's drink history - including Rating.location, which
+ * is a record of where they were - being able to delete it themselves is the minimum,
+ * rather than having to ask the owner.
+ *
+ * The owner cannot delete themselves this way: it would strand the deployment with
+ * no one able to issue invites or manage members.
+ */
+export async function DELETE() {
+  const session = await requireUser()
+  if (session instanceof NextResponse) return session
+
+  const userId = session.user.id
+
+  const user = await prisma.user.findUnique({
+    where: { id: userId },
+    select: { role: true },
+  })
+  if (!user) return NextResponse.json({ error: "Not found" }, { status: 404 })
+  if (user.role === "OWNER") {
+    return NextResponse.json(
+      {
+        error:
+          "The owner account cannot be deleted here. Transfer ownership first.",
+      },
+      { status: 400 }
+    )
+  }
+
+  // Collected before the cascade makes them unreachable.
+  const [drinks, barItems, scans, keys] = await Promise.all([
+    prisma.drink.findMany({ where: { userId }, select: { imageUrl: true } }),
+    prisma.barItem.findMany({ where: { userId }, select: { imageUrl: true } }),
+    prisma.menuScan.findMany({ where: { userId }, select: { imageUrl: true } }),
+    prisma.userApiKey.findMany({ where: { userId }, select: { gatewayKeyId: true } }),
+  ])
+
+  await prisma.user.delete({ where: { id: userId } })
+
+  // Best effort: storage or the gateway being unavailable must not leave the
+  // account half-deleted.
+  const gatewayKeyIds = keys
+    .map((k) => k.gatewayKeyId)
+    .filter((id): id is string => !!id)
+
+  await Promise.all([
+    deleteImagesByUrl([...drinks, ...barItems, ...scans].map((r) => r.imageUrl)),
+    Promise.allSettled(gatewayKeyIds.map((id) => revokeGatewayKey(id))),
+  ])
+
+  // The jwt callback returns null once the user is gone, so the session ends on the
+  // next request without any extra step here.
+  return NextResponse.json({ success: true })
+}

src/app/minio-images/[...key]/route.ts

@@ -19,6 +19,18 @@ import { getImage } from "@/lib/s3"
  */
 export const dynamic = "force-dynamic"
 
+/**
+ * Object keys are namespaced by the user who created them, in two shapes:
+ *   <userId>/...          uploads, and mirrored product images under <userId>/bar/
+ *   scans/<userId>/...    menu scan photos
+ *
+ * Anything else is unreachable by design - if a new writer appears that does not
+ * namespace its keys, its images 404 rather than becoming readable by everyone.
+ */
+function canReadKey(key: string, userId: string): boolean {
+  return key.startsWith(`${userId}/`) || key.startsWith(`scans/${userId}/`)
+}
+
 export async function GET(
   _request: Request,
   { params }: { params: { key: string[] } }
@@ -33,6 +45,11 @@ export async function GET(
     return new Response(null, { status: 400 })
   }
 
+  // 404 rather than 403: do not confirm that someone else's key exists.
+  if (!canReadKey(key, session.user.id)) {
+    return new Response(null, { status: 404 })
+  }
+
   try {
     const object = await getImage(key)
     if (!object.Body) return new Response(null, { status: 404 })

src/components/settings/delete-account-card.tsx

@@ -0,0 +1,84 @@
+"use client"
+
+import { useState } from "react"
+import { signOut } from "next-auth/react"
+import { Loader2, TriangleAlert } from "lucide-react"
+import { Button } from "@/components/ui/button"
+import { Input } from "@/components/ui/input"
+import { Label } from "@/components/ui/label"
+import {
+  Card,
+  CardContent,
+  CardDescription,
+  CardHeader,
+  CardTitle,
+} from "@/components/ui/card"
+
+const CONFIRM_WORD = "delete"
+
+export function DeleteAccountCard() {
+  const [confirm, setConfirm] = useState("")
+  const [error, setError] = useState("")
+  const [loading, setLoading] = useState(false)
+
+  async function handleDelete() {
+    setError("")
+    setLoading(true)
+    try {
+      const res = await fetch("/api/settings/account", { method: "DELETE" })
+      if (!res.ok) {
+        const body = await res.json().catch(() => ({}))
+        setError(body.error || "Could not delete the account")
+        setLoading(false)
+        return
+      }
+      await signOut({ callbackUrl: "/login" })
+    } catch {
+      setError("Something went wrong. Please try again.")
+      setLoading(false)
+    }
+  }
+
+  return (
+    <Card className="border-destructive/40">
+      <CardHeader>
+        <CardTitle className="flex items-center gap-2 text-destructive">
+          <TriangleAlert className="h-5 w-5" />
+          Delete account
+        </CardTitle>
+        <CardDescription>
+          Permanently removes your account and everything in it - drinks, ratings,
+          bar, photos and scans. This cannot be undone. Export a backup first if you
+          want to keep a copy.
+        </CardDescription>
+      </CardHeader>
+      <CardContent className="space-y-3">
+        {error && (
+          <div className="rounded-md bg-destructive/10 p-3 text-sm text-destructive">
+            {error}
+          </div>
+        )}
+        <div className="space-y-2">
+          <Label htmlFor="confirm-delete">
+            Type <span className="font-mono">{CONFIRM_WORD}</span> to confirm
+          </Label>
+          <Input
+            id="confirm-delete"
+            value={confirm}
+            onChange={(e) => setConfirm(e.target.value)}
+            placeholder={CONFIRM_WORD}
+            disabled={loading}
+          />
+        </div>
+        <Button
+          variant="destructive"
+          onClick={handleDelete}
+          disabled={confirm !== CONFIRM_WORD || loading}
+        >
+          {loading ? <Loader2 className="h-4 w-4 animate-spin mr-2" /> : null}
+          Delete my account
+        </Button>
+      </CardContent>
+    </Card>
+  )
+}

src/components/settings/settings-client.tsx

@@ -11,6 +11,7 @@ import { Badge } from "@/components/ui/badge"
 import { Separator } from "@/components/ui/separator"
 import { Key, Trash2, Check, Loader2, Shield, Sliders } from "lucide-react"
 import { BackupRestore } from "@/components/settings/backup-restore"
+import { DeleteAccountCard } from "@/components/settings/delete-account-card"
 
 interface ApiKeyInfo {
   id: string
@@ -141,6 +142,8 @@ export function SettingsClient({ isOwner }: { isOwner: boolean }) {
 
         {/* Backup & Restore Section */}
         <BackupRestore />
+
+        {!isOwner && <DeleteAccountCard />}
       </div>
     </div>
   )

src/lib/backup.ts

@@ -1,5 +1,6 @@
 import { objectsToCsv } from "@/lib/csv"
 import { prisma } from "@/lib/prisma"
+import { imageUrlSchema } from "@/lib/validators"
 import type {
   Drink,
   Rating,
@@ -466,11 +467,42 @@ type DrinkType = "BEER" | "WINE" | "COCKTAIL" | "SPIRIT" | "OTHER"
 type BarItemCategory = "SPIRITS" | "LIQUEURS" | "MIXERS" | "BITTERS" | "GARNISHES" | "TOOLS"
 type BarItemQuantity = "FULL" | "HALF" | "LOW" | "EMPTY"
 
+/**
+ * Upper bound on what one restore may write.
+ *
+ * The restore is correctly scoped to the caller, but nothing bounded its size: a
+ * crafted file could create an unlimited number of rows in a single transaction
+ * against shared Postgres. Self-harm with one user; a denial of service once other
+ * people share the database.
+ */
+const MAX_RESTORE_ROWS = 20000
+
+/**
+ * imageUrl comes straight from an uploaded CSV and never passed through the schema
+ * the API enforces, so a crafted file could put an arbitrary string in the column.
+ */
+function safeImageUrl(value: string | null | undefined): string | null {
+  if (!value) return null
+  return imageUrlSchema.safeParse(value).success ? value : null
+}
+
 export async function executeRestore(
   userId: string,
   data: ParsedBackupData,
   mode: RestoreMode
 ): Promise<RestoreSummary> {
+  const totalRows =
+    data.drinks.length +
+    data.ratings.length +
+    data.wishlistItems.length +
+    data.sharedLists.length +
+    data.barItems.length
+  if (totalRows > MAX_RESTORE_ROWS) {
+    throw new Error(
+      `That backup has ${totalRows} rows, more than the ${MAX_RESTORE_ROWS} allowed in one restore.`
+    )
+  }
+
   return await prisma.$transaction(
     async (tx) => {
       const summary: RestoreSummary = {
@@ -553,7 +585,7 @@ export async function executeRestore(
               region: drink.region ?? null,
               abv: drink.abv ?? null,
               description: drink.description ?? null,
-              imageUrl: drink.imageUrl ?? null,
+              imageUrl: safeImageUrl(drink.imageUrl),
             },
           })
           drinkIdMap.set(drink._originalId, created.id)
@@ -577,7 +609,7 @@ export async function executeRestore(
                   region: drink.region ?? null,
                   abv: drink.abv ?? null,
                   description: drink.description ?? null,
-                  imageUrl: drink.imageUrl ?? null,
+                  imageUrl: safeImageUrl(drink.imageUrl),
                 },
               })
               summary.drinks.updated++
@@ -595,7 +627,7 @@ export async function executeRestore(
                 region: drink.region ?? null,
                 abv: drink.abv ?? null,
                 description: drink.description ?? null,
-                imageUrl: drink.imageUrl ?? null,
+                imageUrl: safeImageUrl(drink.imageUrl),
               },
             })
             drinkIdMap.set(drink._originalId, created.id)

src/lib/images.ts

@@ -0,0 +1,34 @@
+import { deleteImage } from "@/lib/s3"
+
+const PROXY_PREFIX = "/minio-images/"
+
+/** Storage key behind one of our image URLs, or null if it is not one of ours. */
+export function imageKeyFromUrl(url: string | null | undefined): string | null {
+  if (!url || !url.startsWith(PROXY_PREFIX)) return null
+  const key = url.slice(PROXY_PREFIX.length)
+  return key.length > 0 && !key.includes("..") ? key : null
+}
+
+/**
+ * Delete the objects behind these image URLs, ignoring anything that is not ours.
+ *
+ * Always best effort: storage being unavailable must never fail a delete the user
+ * asked for, and must never leave the row behind either. Call after the database
+ * work, and do not await the result for correctness.
+ */
+export async function deleteImagesByUrl(
+  urls: (string | null | undefined)[]
+): Promise<number> {
+  const keys = urls
+    .map(imageKeyFromUrl)
+    .filter((k): k is string => k !== null)
+
+  if (keys.length === 0) return 0
+
+  const results = await Promise.allSettled(keys.map((k) => deleteImage(k)))
+  const failed = results.filter((r) => r.status === "rejected").length
+  if (failed > 0) {
+    console.warn(`[images] ${failed}/${keys.length} object deletions failed`)
+  }
+  return keys.length - failed
+}

src/lib/scan-health.ts

@@ -0,0 +1,60 @@
+import { prisma } from "@/lib/prisma"
+
+/**
+ * Menu scans are processed detached from the request, so a restart - which every
+ * deploy causes - abandons anything in flight and leaves the row PROCESSING
+ * forever, with a spinner that never resolves.
+ *
+ * There is no job queue to recover them, so instead they are reaped lazily whenever
+ * a user looks at their scans. Cheap, needs no scheduler, and the worst case is a
+ * stuck scan showing as failed a little later than it truly failed.
+ */
+const STUCK_AFTER_MS = 15 * 60 * 1000
+
+export async function reapStuckScans(userId: string): Promise<number> {
+  try {
+    const { count } = await prisma.menuScan.updateMany({
+      where: {
+        userId,
+        status: "PROCESSING",
+        updatedAt: { lt: new Date(Date.now() - STUCK_AFTER_MS) },
+      },
+      data: {
+        status: "FAILED",
+        errorMessage: "Processing was interrupted. Please try scanning again.",
+      },
+    })
+    if (count > 0) {
+      console.warn(`[scan] reaped ${count} stuck scan(s) for ${userId}`)
+    }
+    return count
+  } catch (error) {
+    // Never let housekeeping break a page load.
+    console.warn("[scan] reap failed:", error)
+    return 0
+  }
+}
+
+/**
+ * Caps concurrent menu extractions in this process.
+ *
+ * Each one is a vision call with a 4 minute timeout that costs real money, and the
+ * work is detached from the request so nothing else bounds it. With one user this
+ * never mattered; with several it is the difference between a queue and a stampede.
+ */
+const MAX_CONCURRENT_SCANS = 2
+let inFlight = 0
+
+export function tryAcquireScanSlot(): boolean {
+  if (inFlight >= MAX_CONCURRENT_SCANS) return false
+  inFlight += 1
+  return true
+}
+
+export function releaseScanSlot(): void {
+  inFlight = Math.max(0, inFlight - 1)
+}
+
+export function scansInFlight(): number {
+  return inFlight
+}