feat(music): move playlist to authz engine

migrations/20260910000000_role_grants_playlist.sql

@@ -0,0 +1,63 @@
+-- ─────────────────────────────────────────────────────────────────────────
+-- Round 3 (Music) — admit 'playlist' into
+-- `storage.role_grants.resource_type`.
+--
+-- Companion to the domain unblock in
+-- `src/domain/services/authorization.rs`: uncomments
+-- `Resource::Playlist(Uuid)` and its `type_str` / `id` / `from_parts`
+-- arms. Nothing can insert `('playlist', …)` into `role_grants` until
+-- the CHECK constraint permits the discriminator.
+--
+-- The music surface historically enforced access via a dedicated
+-- `audio.playlist_shares` table and bespoke
+-- `MusicStorageAdapter::{user_has_access, user_can_write}` helpers.
+-- Round 3 folds them into the unified ReBAC engine, giving playlists
+-- the same treatment already applied to calendars and address books:
+--
+--   * A single ACL source of truth (`storage.role_grants`) covers
+--     every OxiCloud resource type — files, folders, drives,
+--     calendars, address books, playlists.
+--   * Group subjects become a free feature on playlist shares.
+--   * The `authz.require` audit line ("👮🏻‍♂️ perms: ⛔ …") fires on
+--     denial with no per-domain retrofit.
+--
+-- Owner + share backfill from `audio.playlist_shares` happens in the
+-- companion migration. The legacy table stays in place through this
+-- PR for rollback safety; a follow-up migration one release later
+-- drops it.
+
+-- `resource_type` is a TEXT column with a CHECK constraint (not a PG
+-- enum), so extending it is a DROP / ADD pair — no `ALTER TYPE` /
+-- non-transactional migration issues.
+
+ALTER TABLE storage.role_grants
+    DROP CONSTRAINT IF EXISTS role_grants_resource_type_check;
+
+ALTER TABLE storage.role_grants
+    ADD CONSTRAINT role_grants_resource_type_check
+    CHECK (resource_type IN ('folder', 'file', 'drive', 'calendar', 'address_book', 'playlist'));
+
+-- Post-flight: introspect the live constraint definition and prove
+-- 'playlist' appears. Cheap read-only check with no INSERT.
+DO $BODY$
+DECLARE
+    defn TEXT;
+BEGIN
+    SELECT pg_get_constraintdef(c.oid) INTO defn
+      FROM pg_constraint c
+      JOIN pg_class      t ON t.oid = c.conrelid
+      JOIN pg_namespace  n ON n.oid = t.relnamespace
+     WHERE n.nspname = 'storage'
+       AND t.relname = 'role_grants'
+       AND c.conname = 'role_grants_resource_type_check';
+
+    IF defn IS NULL THEN
+        RAISE EXCEPTION
+            'role_grants_resource_type_check not found on storage.role_grants';
+    END IF;
+    IF position('playlist' IN defn) = 0 THEN
+        RAISE EXCEPTION
+            'CHECK constraint does not admit ''playlist'': %', defn;
+    END IF;
+END;
+$BODY$;

migrations/20260910000001_backfill_playlist_role_grants.sql

@@ -0,0 +1,90 @@
+-- ─────────────────────────────────────────────────────────────────────────
+-- Round 3 (Music) Phase 2 — backfill role_grants from the legacy
+-- per-domain share table.
+--
+-- Companion to `20260910000000_role_grants_playlist.sql` (Phase 1:
+-- CHECK constraint extension). This migration seeds
+-- `storage.role_grants` with:
+--
+--   1. Owner grants for every existing playlist — replaces the
+--      implicit "owner via `audio.playlists.owner_id`" short-circuit
+--      that the bespoke `user_has_access` / `user_can_write` helpers
+--      used.
+--   2. Non-owner grants translated from `audio.playlist_shares` —
+--      existing "shared with me" relationships keep working after the
+--      Phase 3 service rewrite starts reading grants from
+--      `role_grants` only.
+--
+-- The legacy `audio.playlist_shares` table stays in place through
+-- this PR for rollback safety. It gets dropped in a follow-up
+-- migration one release later, once the new engine path bakes.
+--
+-- Idempotent: every INSERT uses `ON CONFLICT DO NOTHING` on the
+-- `(subject_type, subject_id, resource_type, resource_id)` unique
+-- key so a re-run (or a duplicate row in the legacy table where
+-- someone shared with themselves) is a no-op.
+
+-- ── 1. Owner grants for playlists ───────────────────────────────────────
+--
+-- One row per playlist. `granted_by = owner_id` is the self-seeded
+-- creation event — matches the pattern used by the calendar /
+-- address-book backfill and by the drive lifecycle hook for personal
+-- drives.
+INSERT INTO storage.role_grants
+    (subject_type, subject_id, resource_type, resource_id, role, granted_by)
+SELECT 'user', p.owner_id, 'playlist', p.id, 'owner'::storage.grant_role, p.owner_id
+  FROM audio.playlists p
+ON CONFLICT (subject_type, subject_id, resource_type, resource_id)
+    DO NOTHING;
+
+-- ── 2. Non-owner grants from playlist_shares ────────────────────────────
+--
+-- `audio.playlist_shares.can_write` is a BOOLEAN. Map:
+--   - `false` → `viewer` (bundle: Read only)
+--   - `true`  → `editor` (bundle: Read + Update)
+--
+-- `granted_by` = playlist owner, since the legacy share table didn't
+-- track the granter. Best available signal — the owner is the only
+-- principal who could have created the share via the legacy code path.
+INSERT INTO storage.role_grants
+    (subject_type, subject_id, resource_type, resource_id, role, granted_by)
+SELECT
+    'user',
+    s.user_id,
+    'playlist',
+    s.playlist_id,
+    (CASE WHEN s.can_write THEN 'editor' ELSE 'viewer' END)::storage.grant_role,
+    p.owner_id
+  FROM audio.playlist_shares s
+  JOIN audio.playlists       p ON p.id = s.playlist_id
+ WHERE s.user_id <> p.owner_id   -- skip self-shares (owner grant already covers them)
+ON CONFLICT (subject_type, subject_id, resource_type, resource_id)
+    DO NOTHING;
+
+-- ── 3. Post-flight sanity ───────────────────────────────────────────────
+--
+-- Every playlist must now have an owner role_grant. If any row is
+-- missing one, the Phase 3 service rewrite would lock owners out of
+-- their own resources — refuse to leave the migration in that state.
+DO $BODY$
+DECLARE
+    missing_owners BIGINT;
+BEGIN
+    SELECT COUNT(*) INTO missing_owners
+      FROM audio.playlists p
+     WHERE NOT EXISTS (
+         SELECT 1 FROM storage.role_grants g
+          WHERE g.subject_type  = 'user'
+            AND g.subject_id    = p.owner_id
+            AND g.resource_type = 'playlist'
+            AND g.resource_id   = p.id
+            AND g.role          = 'owner'::storage.grant_role
+     );
+
+    IF missing_owners > 0 THEN
+        RAISE EXCEPTION
+            'Round 3 (Music) backfill left % playlists without an Owner role_grant',
+            missing_owners;
+    END IF;
+END;
+$BODY$;

src/application/dtos/grant_dto.rs

@@ -62,6 +62,7 @@ pub enum ResourceTypeDto {
     Drive,
     Calendar,
     AddressBook,
+    Playlist,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
@@ -79,6 +80,7 @@ impl From<ResourceDto> for Resource {
             ResourceTypeDto::Drive => Resource::Drive(dto.id),
             ResourceTypeDto::Calendar => Resource::Calendar(dto.id),
             ResourceTypeDto::AddressBook => Resource::AddressBook(dto.id),
+            ResourceTypeDto::Playlist => Resource::Playlist(dto.id),
         }
     }
 }
@@ -91,6 +93,7 @@ impl From<Resource> for ResourceDto {
             Resource::Drive(id) => (ResourceTypeDto::Drive, id),
             Resource::Calendar(id) => (ResourceTypeDto::Calendar, id),
             Resource::AddressBook(id) => (ResourceTypeDto::AddressBook, id),
+            Resource::Playlist(id) => (ResourceTypeDto::Playlist, id),
         };
         ResourceDto { kind, id }
     }

src/application/ports/authorization_ports.rs

@@ -64,6 +64,7 @@ pub trait AuthorizationEngine: Send + Sync + 'static {
                 Resource::Drive(id) => ("Drive", id),
                 Resource::Calendar(id) => ("Calendar", id),
                 Resource::AddressBook(id) => ("AddressBook", id),
+                Resource::Playlist(id) => ("Playlist", id),
             };
             // Audit-worthy: denials are the interesting signal. Routed
             // through the `audit` tracing target so log aggregators can

src/application/services/magic_link_invite_service.rs

@@ -307,17 +307,22 @@ impl MagicLinkInviteService {
         let (kind, resource_id) = match resource {
             Resource::Folder(id) => (MagicLinkResourceKind::Folder, id),
             Resource::File(id) => (MagicLinkResourceKind::File, id),
-            // Drive / Calendar / AddressBook sharing is out-of-band for
-            // the magic-link flow. Drive shares land through
-            // `/api/drives/{id}/members`; Calendar / AddressBook shares
-            // through the Round-3 `/api/(calendars|address-books)/{id}/shares`
-            // endpoints. The DTOs accept every `Resource` variant on
-            // the wire (see `ResourceTypeDto`) but only file/folder
-            // grants trigger an invitation email. Treating the other
-            // arms as audit-logged suppressed no-ops keeps the grant
-            // in place while matching the ineligible-recipient branch
+            // Drive / Calendar / AddressBook / Playlist sharing is
+            // out-of-band for the magic-link flow. Drive shares land
+            // through `/api/drives/{id}/members`; Calendar /
+            // AddressBook shares through the Round-3
+            // `/api/(calendars|address-books)/{id}/shares` endpoints;
+            // Playlist shares through `/api/playlists/{id}/share`.
+            // The DTOs accept every `Resource` variant on the wire
+            // (see `ResourceTypeDto`) but only file/folder grants
+            // trigger an invitation email. Treating the other arms
+            // as audit-logged suppressed no-ops keeps the grant in
+            // place while matching the ineligible-recipient branch
             // above.
-            Resource::Drive(_) | Resource::Calendar(_) | Resource::AddressBook(_) => {
+            Resource::Drive(_)
+            | Resource::Calendar(_)
+            | Resource::AddressBook(_)
+            | Resource::Playlist(_) => {
                 tracing::info!(
                     target: "audit",
                     event = "magic_link.invitation_suppressed",
@@ -352,12 +357,13 @@ impl MagicLinkInviteService {
             Resource::Folder(_) => "server.magic_link.email.kind_folder",
             Resource::File(_) => "server.magic_link.email.kind_file",
             // Unreachable — the early-return above exits before we get
-            // here for Drive / Calendar / AddressBook resources. The
-            // arms exist only to satisfy exhaustiveness; if you find
-            // any firing, the early-return was bypassed.
-            Resource::Drive(_) | Resource::Calendar(_) | Resource::AddressBook(_) => {
-                "server.magic_link.email.kind_folder"
-            }
+            // here for Drive / Calendar / AddressBook / Playlist
+            // resources. The arms exist only to satisfy exhaustiveness;
+            // if you find any firing, the early-return was bypassed.
+            Resource::Drive(_)
+            | Resource::Calendar(_)
+            | Resource::AddressBook(_)
+            | Resource::Playlist(_) => "server.magic_link.email.kind_folder",
         };
         // PR C: render in the recipient's preferred locale (set by UI
         // switcher, OIDC JIT claim, or inviter inheritance at row

src/application/services/music_service.rs

@@ -1,3 +1,4 @@
+use std::collections::HashSet;
 use std::sync::Arc;
 use uuid::Uuid;
 
@@ -8,28 +9,77 @@ use crate::application::dtos::playlist_dto::{
 use crate::application::ports::authorization_ports::AuthorizationEngine;
 use crate::application::ports::music_ports::{MusicStoragePort, MusicUseCase};
 use crate::common::errors::{DomainError, ErrorKind};
-use crate::domain::services::authorization::{Permission, Resource, Subject};
+use crate::domain::services::authorization::{Permission, Resource, Role, Subject};
 use crate::infrastructure::adapters::music_storage_adapter::MusicStorageAdapter;
 use crate::infrastructure::services::pg_acl_engine::PgAclEngine;
 
+/// Music service — the REST entry point for every playlist or audio
+/// metadata operation. Every method routes through
+/// `AuthorizationEngine`; the pre-Round-3 `user_has_access` /
+/// `user_can_write` bespoke helpers on `MusicStorageAdapter` are no
+/// longer consulted for access decisions.
+///
+/// Ownership + sharing live entirely in `storage.role_grants`
+/// (`resource_type='playlist'`). `audio.playlists.owner_id` stays for
+/// provenance and legacy queries; `audio.playlist_shares` is
+/// backfilled and slated for removal in a follow-up migration.
 pub struct MusicService {
     storage: Arc<MusicStorageAdapter>,
-    /// ReBAC engine — Round 1 fix from `docs/plan/authz_audit/`.
-    /// Currently used ONLY by `get_audio_metadata` to close the
-    /// cross-tenant IDOR (`_user_id: Uuid` was deliberately unused).
-    /// The full engine rewrite (Round 3 — `Resource::Playlist` +
-    /// authz.require on every playlist verb) is a separate PR;
-    /// don't extend the bespoke `user_has_access` / `user_can_write`
-    /// pattern to new methods, use `require` here instead.
-    authorization: Arc<PgAclEngine>,
+    /// ReBAC engine — every user-facing method calls `authz.require`
+    /// with the appropriate `Permission`. `create_playlist` also uses
+    /// it to seed an Owner grant for the caller, so the common
+    /// "owning my own playlist" case takes a single indexed
+    /// role_grants lookup on subsequent reads.
+    authz: Arc<PgAclEngine>,
 }
 
 impl MusicService {
-    pub fn new(storage: Arc<MusicStorageAdapter>, authorization: Arc<PgAclEngine>) -> Self {
-        Self {
-            storage,
-            authorization,
-        }
+    pub fn new(storage: Arc<MusicStorageAdapter>, authz: Arc<PgAclEngine>) -> Self {
+        Self { storage, authz }
+    }
+
+    /// Parse `playlist_id` and enforce `permission` on
+    /// `Resource::Playlist(uuid)`. On denial `authz.require` returns
+    /// `NotFound` (anti-enum — same shape as "no such playlist") and
+    /// emits the `authz.denied` audit line. Returns the parsed UUID
+    /// on success so the caller doesn't have to parse it a second
+    /// time.
+    async fn require_playlist_perm(
+        &self,
+        playlist_id: &str,
+        caller_id: Uuid,
+        permission: Permission,
+    ) -> Result<Uuid, DomainError> {
+        let uuid = Uuid::parse_str(playlist_id)
+            .map_err(|_| DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid ID"))?;
+        self.authz
+            .require(
+                Subject::User(caller_id),
+                permission,
+                Resource::Playlist(uuid),
+            )
+            .await?;
+        Ok(uuid)
+    }
+
+    /// Check `permission` on a playlist without throwing. Used by the
+    /// read paths that also allow a public-playlist bypass — they
+    /// need a bool, not a `Result<(), NotFound>`.
+    async fn has_playlist_perm(
+        &self,
+        playlist_id: &str,
+        caller_id: Uuid,
+        permission: Permission,
+    ) -> Result<bool, DomainError> {
+        let uuid = Uuid::parse_str(playlist_id)
+            .map_err(|_| DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid ID"))?;
+        self.authz
+            .check(
+                Subject::User(caller_id),
+                permission,
+                Resource::Playlist(uuid),
+            )
+            .await
     }
 }
 
@@ -39,7 +89,26 @@ impl MusicUseCase for MusicService {
         dto: CreatePlaylistDto,
         user_id: Uuid,
     ) -> Result<PlaylistDto, DomainError> {
-        self.storage.create_playlist(dto, user_id).await
+        // No pre-write gate: creating a playlist is a personal act.
+        // Storage stamps `owner_id = user_id`; we then seed an Owner
+        // role_grant so subsequent reads hit the same
+        // `storage.role_grants` fast path used everywhere else.
+        let created = self.storage.create_playlist(dto, user_id).await?;
+        let playlist_uuid = Uuid::parse_str(&created.id).map_err(|_| {
+            DomainError::internal_error("Playlist", "storage returned invalid playlist id")
+        })?;
+        // `set_role` is idempotent on the `(subject, resource)` unique
+        // key. `granted_by = user_id` is the self-seeded creation event.
+        self.authz
+            .set_role(
+                user_id,
+                Subject::User(user_id),
+                Role::Owner,
+                Resource::Playlist(playlist_uuid),
+                None,
+            )
+            .await?;
+        Ok(created)
     }
 
     async fn update_playlist(
@@ -48,45 +117,25 @@ impl MusicUseCase for MusicService {
         dto: UpdatePlaylistDto,
         user_id: Uuid,
     ) -> Result<PlaylistDto, DomainError> {
-        let has_access = self.storage.user_has_access(playlist_id, user_id).await?;
-        if !has_access {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "You don't have permission to update this playlist",
-            ));
-        }
-        let can_write = self.storage.user_can_write(playlist_id, user_id).await?;
-        if !can_write {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "You need write access to update this playlist",
-            ));
-        }
+        self.require_playlist_perm(playlist_id, user_id, Permission::Update)
+            .await?;
         self.storage.update_playlist(playlist_id, dto).await
     }
 
     async fn delete_playlist(&self, playlist_id: &str, user_id: Uuid) -> Result<(), DomainError> {
-        let playlist = self.storage.get_playlist(playlist_id).await?;
-        let playlist = match playlist {
-            Some(p) => p,
-            None => {
-                return Err(DomainError::new(
-                    ErrorKind::NotFound,
-                    "Playlist",
-                    "Playlist not found",
-                ));
-            }
-        };
-        if playlist.owner_id != user_id.to_string() {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "Only the owner can delete this playlist",
-            ));
-        }
-        self.storage.delete_playlist(playlist_id).await
+        let uuid = self
+            .require_playlist_perm(playlist_id, user_id, Permission::Delete)
+            .await?;
+        self.storage.delete_playlist(playlist_id).await?;
+        // Wipe every grant on this playlist so a re-used UUID
+        // (impossible today but cheap to defend against) doesn't
+        // inherit stale ACLs. The storage DELETE won't cascade to
+        // `storage.role_grants` — it's cross-schema.
+        let _ = self
+            .authz
+            .revoke_all_for_resource(Resource::Playlist(uuid))
+            .await;
+        Ok(())
     }
 
     async fn get_playlist(
@@ -94,23 +143,22 @@ impl MusicUseCase for MusicService {
         playlist_id: &str,
         user_id: Uuid,
     ) -> Result<PlaylistDto, DomainError> {
-        let has_access = self.storage.user_has_access(playlist_id, user_id).await?;
-        if !has_access {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "You don't have permission to view this playlist",
-            ));
-        }
         let playlist = self.storage.get_playlist(playlist_id).await?;
-        match playlist {
-            Some(p) => Ok(p),
-            None => Err(DomainError::new(
-                ErrorKind::NotFound,
-                "Playlist",
-                "Playlist not found",
-            )),
+        let playlist = match playlist {
+            Some(p) => p,
+            None => return Err(DomainError::not_found("Playlist", playlist_id)),
+        };
+        // Public-playlist bypass: anonymous-ish read. `check` returns
+        // bool (no throw); combine with the public flag before
+        // deciding.
+        let allowed = playlist.is_public
+            || self
+                .has_playlist_perm(playlist_id, user_id, Permission::Read)
+                .await?;
+        if !allowed {
+            return Err(DomainError::not_found("Playlist", playlist_id));
         }
+        Ok(playlist)
     }
 
     async fn list_playlists(
@@ -123,17 +171,38 @@ impl MusicUseCase for MusicService {
         let limit = query.limit.unwrap_or(100);
         let offset = query.offset.unwrap_or(0);
 
-        let mut playlists = Vec::new();
+        // Post-Round-3 semantics: playlists the caller has any grant
+        // on come from `list_incoming_grants` — one union of owned +
+        // shared. The pre-Round-3 code fetched them via two separate
+        // queries (`list_playlists_by_owner` + `list_shared_with_user`)
+        // that each read a different table.
+        let grants = self
+            .authz
+            .list_incoming_grants(Subject::User(user_id))
+            .await?;
 
-        let owned = self.storage.list_playlists_by_owner(user_id).await?;
-        playlists.extend(owned);
+        // Deduplicate — a user can hold multiple grants on the same
+        // playlist (direct + group-inherited). We only need one DTO
+        // per resource.
+        let mut playlist_ids: HashSet<Uuid> = grants
+            .into_iter()
+            .filter_map(|g| match g.resource {
+                Resource::Playlist(id) => Some(id),
+                _ => None,
+            })
+            .collect();
 
-        if include_shared {
-            let shared = self.storage.list_shared_with_user(user_id).await?;
-            for s in shared {
-                if !playlists.iter().any(|p: &PlaylistDto| p.id == s.id) {
-                    playlists.push(s);
-                }
+        // `include_shared=false` narrows the listing to owned playlists
+        // only. Owner is a grant like any other in `role_grants`, so we
+        // filter the aggregated set against the owner_id stamped on
+        // each row after hydration — cheaper than a second SQL round-trip.
+        let mut playlists: Vec<PlaylistDto> = Vec::with_capacity(playlist_ids.len());
+        let user_str = user_id.to_string();
+        for id in playlist_ids.drain() {
+            if let Ok(Some(p)) = self.storage.get_playlist(&id.to_string()).await
+                && (include_shared || p.owner_id == user_str)
+            {
+                playlists.push(p);
             }
         }
 
@@ -155,26 +224,9 @@ impl MusicUseCase for MusicService {
         dto: AddTracksDto,
         user_id: Uuid,
     ) -> Result<Vec<PlaylistItemDto>, DomainError> {
-        let playlist_uuid = Uuid::parse_str(playlist_id).map_err(|_| {
-            DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid playlist ID")
-        })?;
-
-        let has_access = self.storage.user_has_access(playlist_id, user_id).await?;
-        if !has_access {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "You don't have permission to modify this playlist",
-            ));
-        }
-        let can_write = self.storage.user_can_write(playlist_id, user_id).await?;
-        if !can_write {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "You need write access to add tracks",
-            ));
-        }
+        let playlist_uuid = self
+            .require_playlist_perm(playlist_id, user_id, Permission::Update)
+            .await?;
 
         let file_ids: Result<Vec<Uuid>, _> =
             dto.file_ids.iter().map(|id| Uuid::parse_str(id)).collect();
@@ -191,30 +243,12 @@ impl MusicUseCase for MusicService {
         file_id: &str,
         user_id: Uuid,
     ) -> Result<(), DomainError> {
-        let playlist_uuid = Uuid::parse_str(playlist_id).map_err(|_| {
-            DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid playlist ID")
-        })?;
+        let playlist_uuid = self
+            .require_playlist_perm(playlist_id, user_id, Permission::Update)
+            .await?;
         let file_uuid = Uuid::parse_str(file_id).map_err(|_| {
             DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid file ID")
         })?;
-
-        let has_access = self.storage.user_has_access(playlist_id, user_id).await?;
-        if !has_access {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "You don't have permission to modify this playlist",
-            ));
-        }
-        let can_write = self.storage.user_can_write(playlist_id, user_id).await?;
-        if !can_write {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "You need write access to remove tracks",
-            ));
-        }
-
         self.storage.remove_track(&playlist_uuid, &file_uuid).await
     }
 
@@ -224,26 +258,9 @@ impl MusicUseCase for MusicService {
         dto: ReorderTracksDto,
         user_id: Uuid,
     ) -> Result<(), DomainError> {
-        let playlist_uuid = Uuid::parse_str(playlist_id).map_err(|_| {
-            DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid playlist ID")
-        })?;
-
-        let has_access = self.storage.user_has_access(playlist_id, user_id).await?;
-        if !has_access {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "You don't have permission to modify this playlist",
-            ));
-        }
-        let can_write = self.storage.user_can_write(playlist_id, user_id).await?;
-        if !can_write {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "You need write access to reorder tracks",
-            ));
-        }
+        let playlist_uuid = self
+            .require_playlist_perm(playlist_id, user_id, Permission::Update)
+            .await?;
 
         let item_ids: Result<Vec<Uuid>, _> =
             dto.item_ids.iter().map(|id| Uuid::parse_str(id)).collect();
@@ -262,16 +279,21 @@ impl MusicUseCase for MusicService {
         let playlist_uuid = Uuid::parse_str(playlist_id).map_err(|_| {
             DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid playlist ID")
         })?;
-
-        let has_access = self.storage.user_has_access(playlist_id, user_id).await?;
-        if !has_access {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "You don't have permission to view this playlist",
-            ));
+        // Public-playlist bypass mirrors `get_playlist`: readers of a
+        // public playlist can see its tracks. Fetch the playlist row
+        // to inspect `is_public` before deciding.
+        let playlist = self
+            .storage
+            .get_playlist(playlist_id)
+            .await?
+            .ok_or_else(|| DomainError::not_found("Playlist", playlist_id))?;
+        let allowed = playlist.is_public
+            || self
+                .has_playlist_perm(playlist_id, user_id, Permission::Read)
+                .await?;
+        if !allowed {
+            return Err(DomainError::not_found("Playlist", playlist_id));
         }
-
         self.storage.list_playlist_tracks(&playlist_uuid).await
     }
 
@@ -281,36 +303,33 @@ impl MusicUseCase for MusicService {
         dto: SharePlaylistDto,
         caller_id: Uuid,
     ) -> Result<(), DomainError> {
-        let playlist = self.storage.get_playlist(playlist_id).await?;
-        let playlist = match playlist {
-            Some(p) => p,
-            None => {
-                return Err(DomainError::new(
-                    ErrorKind::NotFound,
-                    "Playlist",
-                    "Playlist not found",
-                ));
-            }
-        };
-        if playlist.owner_id != caller_id.to_string() {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "Only the owner can share this playlist",
-            ));
-        }
-
-        let playlist_uuid = Uuid::parse_str(playlist_id).map_err(|_| {
-            DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid playlist ID")
-        })?;
+        let playlist_uuid = self
+            .require_playlist_perm(playlist_id, caller_id, Permission::Share)
+            .await?;
         let target_user_id = Uuid::parse_str(&dto.user_id).map_err(|_| {
             DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid user ID")
         })?;
-        let can_write = dto.can_write.unwrap_or(false);
-
-        self.storage
-            .share_playlist(&playlist_uuid, target_user_id, can_write)
-            .await
+        // Legacy `can_write` boolean maps into the role bundle system:
+        //   - false → Viewer (Read only)
+        //   - true  → Editor (Read + Update)
+        // The endpoint stays boolean-shaped for API back-compat; new
+        // integrations should switch to the unified `/api/grants` API
+        // which exposes the full role set.
+        let role = if dto.can_write.unwrap_or(false) {
+            Role::Editor
+        } else {
+            Role::Viewer
+        };
+        self.authz
+            .set_role(
+                caller_id,
+                Subject::User(target_user_id),
+                role,
+                Resource::Playlist(playlist_uuid),
+                None,
+            )
+            .await?;
+        Ok(())
     }
 
     async fn remove_share(
@@ -319,33 +338,18 @@ impl MusicUseCase for MusicService {
         target_user_id: &str,
         caller_id: Uuid,
     ) -> Result<(), DomainError> {
-        let playlist = self.storage.get_playlist(playlist_id).await?;
-        let playlist = match playlist {
-            Some(p) => p,
-            None => {
-                return Err(DomainError::new(
-                    ErrorKind::NotFound,
-                    "Playlist",
-                    "Playlist not found",
-                ));
-            }
-        };
-        if playlist.owner_id != caller_id.to_string() {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "Only the owner can manage sharing",
-            ));
-        }
-
-        let playlist_uuid = Uuid::parse_str(playlist_id).map_err(|_| {
-            DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid playlist ID")
-        })?;
+        let playlist_uuid = self
+            .require_playlist_perm(playlist_id, caller_id, Permission::Share)
+            .await?;
         let target_uuid = Uuid::parse_str(target_user_id).map_err(|_| {
             DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid user ID")
         })?;
-
-        self.storage.remove_share(&playlist_uuid, target_uuid).await
+        self.authz
+            .clear_role(
+                Subject::User(target_uuid),
+                Resource::Playlist(playlist_uuid),
+            )
+            .await
     }
 
     async fn get_playlist_shares(
@@ -353,35 +357,26 @@ impl MusicUseCase for MusicService {
         playlist_id: &str,
         user_id: Uuid,
     ) -> Result<Vec<PlaylistShareInfoDto>, DomainError> {
-        let playlist = self.storage.get_playlist(playlist_id).await?;
-        let playlist = match playlist {
-            Some(p) => p,
-            None => {
-                return Err(DomainError::new(
-                    ErrorKind::NotFound,
-                    "Playlist",
-                    "Playlist not found",
-                ));
-            }
-        };
-        if playlist.owner_id != user_id.to_string() {
-            return Err(DomainError::new(
-                ErrorKind::AccessDenied,
-                "Playlist",
-                "Only the owner can view sharing info",
-            ));
-        }
-
-        let playlist_uuid = Uuid::parse_str(playlist_id).map_err(|_| {
-            DomainError::new(ErrorKind::InvalidInput, "Playlist", "Invalid playlist ID")
-        })?;
-
-        let shares = self.storage.get_shares(&playlist_uuid).await?;
-        Ok(shares
+        let playlist_uuid = self
+            .require_playlist_perm(playlist_id, user_id, Permission::Share)
+            .await?;
+        // `list_grants_on_resource` returns every role_grant row for
+        // the playlist. Drop the Owner self-grant seeded at creation
+        // (the caller already knows they own it) and collapse the
+        // role bundle back to a boolean `can_write` for the legacy
+        // DTO shape.
+        let grants = self
+            .authz
+            .list_grants_on_resource(Resource::Playlist(playlist_uuid))
+            .await?;
+        Ok(grants
             .into_iter()
-            .map(|(uid, can_write)| PlaylistShareInfoDto {
-                user_id: uid.to_string(),
-                can_write,
+            .filter_map(|g| match g.subject {
+                Subject::User(uid) if g.role != Role::Owner => Some(PlaylistShareInfoDto {
+                    user_id: uid.to_string(),
+                    can_write: g.role.expand().contains(&Permission::Update),
+                }),
+                _ => None,
             })
             .collect())
     }
@@ -398,9 +393,8 @@ impl MusicUseCase for MusicService {
         // metadata for any known file id (cross-tenant IDOR — the
         // `_user_id` parameter was deliberately unused). `require`
         // returns 404 on denial to match the anti-enum shape used
-        // everywhere else. Post-Drive AuthZ audit fix (Round 1
-        // BLOCKER — `docs/plan/authz_audit/rest_storage.md`).
-        self.authorization
+        // everywhere else.
+        self.authz
             .require(
                 Subject::User(caller_id),
                 Permission::Read,

src/application/services/recipient_notification_service.rs

@@ -472,13 +472,14 @@ impl RecipientNotificationService {
         let kind_key = match resource {
             Resource::Folder(_) => "server.magic_link.email.kind_folder",
             Resource::File(_) => "server.magic_link.email.kind_file",
-            // Drive / Calendar / AddressBook shares don't produce
-            // email notifications through this path. Fall back to the
-            // folder label so any code that does reach here still
-            // produces a readable (if generic) mail body.
-            Resource::Drive(_) | Resource::Calendar(_) | Resource::AddressBook(_) => {
-                "server.magic_link.email.kind_folder"
-            }
+            // Drive / Calendar / AddressBook / Playlist shares don't
+            // produce email notifications through this path. Fall
+            // back to the folder label so any code that does reach
+            // here still produces a readable (if generic) mail body.
+            Resource::Drive(_)
+            | Resource::Calendar(_)
+            | Resource::AddressBook(_)
+            | Resource::Playlist(_) => "server.magic_link.email.kind_folder",
         };
         let kind_label = self.i18n_or(kind_key, &locale, &[]).await;
         // Short form for the subject, long form (with email) for the

src/domain/services/authorization.rs

@@ -90,9 +90,12 @@ pub enum Resource {
     /// replaces `carddav.address_book_shares` and the
     /// `check_address_book_access` bespoke helper.
     AddressBook(Uuid),
-    // Reserved for future use — same shape but tracked separately
-    // (music-service rewrite is its own PR):
-    // Playlist(Uuid),
+    /// A music playlist. Same shape as `Calendar`/`AddressBook` —
+    /// `storage.role_grants` with `resource_type='playlist'` replaces
+    /// the pre-Round-3 dedicated `music.playlist_shares` table and the
+    /// bespoke `user_has_access` / `user_can_write` helpers on
+    /// `MusicStorageAdapter`.
+    Playlist(Uuid),
 }
 
 impl Resource {
@@ -103,7 +106,7 @@ impl Resource {
             Resource::Drive(_) => "drive",
             Resource::Calendar(_) => "calendar",
             Resource::AddressBook(_) => "address_book",
-            //Resource::Playlist(_) => "playlist",
+            Resource::Playlist(_) => "playlist",
         }
     }
 
@@ -113,8 +116,8 @@ impl Resource {
             | Resource::File(id)
             | Resource::Drive(id)
             | Resource::Calendar(id)
-            | Resource::AddressBook(id) => *id,
-            //| Resource::Playlist(id)
+            | Resource::AddressBook(id)
+            | Resource::Playlist(id) => *id,
         }
     }
 
@@ -125,7 +128,7 @@ impl Resource {
             "drive" => Some(Resource::Drive(id)),
             "calendar" => Some(Resource::Calendar(id)),
             "address_book" => Some(Resource::AddressBook(id)),
-            //"playlist" => Some(Resource::Playlist(id)),
+            "playlist" => Some(Resource::Playlist(id)),
             _ => None,
         }
     }
@@ -552,12 +555,11 @@ mod tests {
             Resource::File(id),
             Resource::Calendar(id),
             Resource::AddressBook(id),
+            Resource::Playlist(id),
         ] {
             let back = Resource::from_parts(r.type_str(), r.id()).unwrap();
             assert_eq!(r, back);
         }
-        // `playlist` is still pending the Music AuthZ migration.
-        assert!(Resource::from_parts("playlist", id).is_none());
     }
 
     #[test]

src/infrastructure/services/pg_acl_engine.rs

@@ -480,17 +480,22 @@ impl PgAclEngine {
     /// drive — this returns `NotFound` for `Resource::Drive` and the caller
     /// must not invoke it on Drive resources.
     ///
-    /// `Resource::Calendar` and `Resource::AddressBook` are top-level per
-    /// user with no drive ancestor; they also return `NotFound` and the
-    /// engine short-circuits to a direct `role_grants` lookup (no drive
+    /// `Resource::Calendar`, `Resource::AddressBook` and
+    /// `Resource::Playlist` are top-level per user with no drive
+    /// ancestor; they also return `NotFound` and the engine
+    /// short-circuits to a direct `role_grants` lookup (no drive
     /// precheck applies).
     async fn drive_of(&self, resource: Resource) -> Result<Uuid, DomainError> {
         match resource {
             Resource::Folder(id) => self.folder_repo.get_folder_drive_id(&id.to_string()).await,
             Resource::File(id) => self.file_repo.get_file_drive_id(&id.to_string()).await,
-            Resource::Drive(_) | Resource::Calendar(_) | Resource::AddressBook(_) => Err(
-                DomainError::not_found(resource.type_str(), resource.id().to_string()),
-            ),
+            Resource::Drive(_)
+            | Resource::Calendar(_)
+            | Resource::AddressBook(_)
+            | Resource::Playlist(_) => Err(DomainError::not_found(
+                resource.type_str(),
+                resource.id().to_string(),
+            )),
         }
     }
 
@@ -902,6 +907,19 @@ impl PgAclEngine {
                 )
                 .await
             }
+            Resource::Playlist(id) => {
+                let (subject_types, subject_ids) =
+                    self.subject_match_set(subject, counters).await?;
+                self.direct_grant_exists(
+                    &subject_types,
+                    &subject_ids,
+                    permission,
+                    "playlist",
+                    id,
+                    counters,
+                )
+                .await
+            }
         }
     }
 }

src/interfaces/api/handlers/grant_handler.rs

@@ -113,12 +113,12 @@ pub async fn create_grant(
             .get_by_id(id)
             .await
             .map(|d| d.drive.typed_policies()),
-        // Calendars and address books live outside the drive
-        // hierarchy (top-level per user), so no drive-level policy
-        // gates apply. If per-calendar / per-address-book policies
-        // ever ship, they'll live on the resource itself, not on a
+        // Calendars, address books and playlists live outside the
+        // drive hierarchy (top-level per user), so no drive-level
+        // policy gates apply. If per-resource policies ever ship for
+        // these kinds, they'll live on the resource itself, not on a
         // drive; the default-empty bag is the right no-op here.
-        Resource::Calendar(_) | Resource::AddressBook(_) => {
+        Resource::Calendar(_) | Resource::AddressBook(_) | Resource::Playlist(_) => {
             Ok(crate::domain::entities::drive::DrivePolicies::default())
         }
     };

tests/api/playlists.hurl

@@ -0,0 +1,408 @@
+# =============================================================
+# OxiCloud – Music (playlist) + Round-3 AuthZ end-to-end scenario
+# =============================================================
+# Verifies the full playlist REST surface post-Round-3:
+#
+#   * `POST /api/playlists` seeds an Owner grant on
+#     `Resource::Playlist(uuid)` so the caller can see it via the
+#     unified engine (list, get) on the very next request.
+#   * `GET /api/playlists` returns the union of owned + shared
+#     playlists via `authz.list_incoming_grants`; the pre-Round-3
+#     owner-only + separate shared query pair is gone.
+#   * Cross-user reads (`GET /api/playlists/{id}`) return the 404
+#     anti-enum shape (was 403 in the bespoke
+#     `user_has_access` era).
+#   * Sharing works through BOTH surfaces post-migration:
+#       - Generic `POST /api/grants` with `resource.type = "playlist"`
+#         (first-class ReBAC variant added in this PR)
+#       - Legacy `POST /api/playlists/{id}/share` (bool `can_write`)
+#         still routes through the same `role_grants` table via
+#         `authz.set_role`, so both flows converge on the unified
+#         engine.
+#   * `GET /api/playlists/{id}/shares` reads `list_grants_on_resource`
+#     and hides the Owner self-grant.
+#   * Revoke through either surface drops the playlist from the
+#     recipient's listing.
+#   * Viewer role blocks writes: `Update`/`Delete`/`Share` all 404 for
+#     a Viewer, matching the anti-enum shape.
+#
+# The `playlist_id` is captured from the POST response body. Fresh CI
+# database via `tests/api/run.sh`, so admin has no prior playlists —
+# the JSONPath capture from `GET /api/playlists` is unambiguous.
+# =============================================================
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 1 – Alice (admin) logs in.
+# ─────────────────────────────────────────────────────────────
+POST {{base_url}}/api/auth/login
+Content-Type: application/json
+{
+  "username": "{{username}}",
+  "password": "{{password}}"
+}
+
+HTTP 200
+[Captures]
+alice_token: jsonpath "$.access_token"
+alice_user_id: jsonpath "$.user.id"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 2 – Alice creates a playlist. The response body carries the
+# server-assigned UUID and `owner_id == alice_user_id`. The service
+# also seeds an Owner role_grant on `Resource::Playlist(uuid)` —
+# proven by Step 4 which lists playlists via
+# `authz.list_incoming_grants` and expects this one to surface.
+# ─────────────────────────────────────────────────────────────
+POST {{base_url}}/api/playlists
+Authorization: Bearer {{alice_token}}
+Content-Type: application/json
+{
+  "name": "round3-playlist",
+  "description": "Music AuthZ migration coverage"
+}
+
+HTTP 201
+[Captures]
+playlist_id: jsonpath "$.id"
+[Asserts]
+jsonpath "$.name" == "round3-playlist"
+jsonpath "$.owner_id" == "{{alice_user_id}}"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 3 – Alice GETs the playlist she just created. This is the
+# fast-path validation of the Owner grant seeded at create time:
+# without it, `authz.require(Read)` would return NotFound and this
+# would 404.
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/playlists/{{playlist_id}}
+Authorization: Bearer {{alice_token}}
+
+HTTP 200
+[Asserts]
+jsonpath "$.id" == "{{playlist_id}}"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 4 – Alice lists playlists — hers appears exactly once.
+# The service reads `list_incoming_grants(Alice)` and filters to
+# `Resource::Playlist`, so this exercises the same code path as
+# CalDAV's `list_my_calendars`.
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/playlists
+Authorization: Bearer {{alice_token}}
+
+HTTP 200
+[Asserts]
+jsonpath "$[*].id" contains "{{playlist_id}}"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 5 – Provision Bob. Idempotent: `HTTP *` accepts 201 first
+# run, 409 subsequent runs. Login is the real precondition.
+# ─────────────────────────────────────────────────────────────
+POST {{base_url}}/api/admin/users
+Authorization: Bearer {{alice_token}}
+Content-Type: application/json
+{
+  "username": "music_bob",
+  "password": "MusicBobPassword1!",
+  "email":    "music_bob@example.com",
+  "role":     "user"
+}
+
+HTTP *
+
+
+POST {{base_url}}/api/auth/login
+Content-Type: application/json
+{
+  "username": "music_bob",
+  "password": "MusicBobPassword1!"
+}
+
+HTTP 200
+[Captures]
+bob_token: jsonpath "$.access_token"
+bob_user_id: jsonpath "$.user.id"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 6 – Cross-user GET on Alice's playlist → 404. Before Round 3
+# this was the bespoke `user_has_access` denial which returned 403;
+# post-migration `authz.require(Read)` denies with `NotFound` for
+# anti-enumeration parity with files/folders/drives.
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/playlists/{{playlist_id}}
+Authorization: Bearer {{bob_token}}
+
+HTTP 404
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 7 – Bob's playlist listing does NOT include Alice's. The
+# `list_incoming_grants(Bob)` call sees no grant on that playlist,
+# so nothing surfaces.
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/playlists
+Authorization: Bearer {{bob_token}}
+
+HTTP 200
+[Asserts]
+jsonpath "$..id" not contains "{{playlist_id}}"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 8 – Alice shares the playlist with Bob as Viewer via the
+# generic ReBAC grant endpoint. `resource.type = "playlist"` is a
+# first-class variant added by this PR; before Round 3, this
+# request would 400 (Unsupported resource type).
+# ─────────────────────────────────────────────────────────────
+POST {{base_url}}/api/grants
+Authorization: Bearer {{alice_token}}
+Content-Type: application/json
+{
+  "subject":  { "type": "user", "id": "{{bob_user_id}}" },
+  "resource": { "type": "playlist", "id": "{{playlist_id}}" },
+  "role":     "viewer"
+}
+
+HTTP 201
+[Captures]
+share_grant_id: jsonpath "$.grants[0].id"
+[Asserts]
+jsonpath "$.grants[0].role" == "viewer"
+jsonpath "$.grants[0].resource.type" == "playlist"
+jsonpath "$.grants[0].resource.id" == "{{playlist_id}}"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 9 – Bob GET now succeeds. `authz.require(Read)` sees the
+# Viewer role_grant row and grants access.
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/playlists/{{playlist_id}}
+Authorization: Bearer {{bob_token}}
+
+HTTP 200
+[Asserts]
+jsonpath "$.id" == "{{playlist_id}}"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 10 – Bob's listing now surfaces Alice's playlist — proving
+# the owned + shared union in `list_playlists`.
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/playlists?include_shared=true
+Authorization: Bearer {{bob_token}}
+
+HTTP 200
+[Asserts]
+jsonpath "$[*].id" contains "{{playlist_id}}"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 11 – Bob cannot rename the playlist. Viewer's bundle is
+# Read-only (no Update), so `require_playlist_perm(Update)` denies
+# with the 404 anti-enum shape.
+# ─────────────────────────────────────────────────────────────
+PUT {{base_url}}/api/playlists/{{playlist_id}}
+Authorization: Bearer {{bob_token}}
+Content-Type: application/json
+{ "name": "hijacked" }
+
+HTTP 404
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 12 – Bob cannot delete the playlist. Viewer's bundle
+# excludes Delete → 404.
+# ─────────────────────────────────────────────────────────────
+DELETE {{base_url}}/api/playlists/{{playlist_id}}
+Authorization: Bearer {{bob_token}}
+
+HTTP 404
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 13 – Bob cannot re-share the playlist. Viewer's bundle
+# excludes Share → 404 on the legacy /share endpoint (which now
+# routes through `authz.require(Share)`).
+# ─────────────────────────────────────────────────────────────
+POST {{base_url}}/api/playlists/{{playlist_id}}/share
+Authorization: Bearer {{bob_token}}
+Content-Type: application/json
+{ "user_id": "{{alice_user_id}}", "can_write": true }
+
+HTTP 404
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 14 – Alice lists shares via the legacy endpoint. The
+# service reads `list_grants_on_resource` and drops the Owner
+# self-grant, so exactly one row surfaces: Bob as Viewer
+# (can_write=false).
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/playlists/{{playlist_id}}/shares
+Authorization: Bearer {{alice_token}}
+
+HTTP 200
+[Asserts]
+jsonpath "$[*].user_id" contains "{{bob_user_id}}"
+jsonpath "$[?(@.user_id == '{{bob_user_id}}')].can_write" == false
+jsonpath "$[*].user_id" not contains "{{alice_user_id}}"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 14b – Same query, unified endpoint. `GET /api/grants?
+# resource_type=playlist&resource_id=…` requires `Share` on the
+# resource (same gate as the legacy /shares endpoint) and returns
+# the raw `role_grants` rows — including the Owner self-grant that
+# the legacy DTO hides. Confirms `ResourceTypeDto::Playlist` is
+# admitted at the wire boundary and that both surfaces read the
+# same underlying data.
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/grants?resource_type=playlist&resource_id={{playlist_id}}
+Authorization: Bearer {{alice_token}}
+
+HTTP 200
+[Asserts]
+jsonpath "$[*].subject.id" contains "{{bob_user_id}}"
+jsonpath "$[*].subject.id" contains "{{alice_user_id}}"
+jsonpath "$[?(@.subject.id == '{{bob_user_id}}')].role" == "viewer"
+jsonpath "$[?(@.subject.id == '{{alice_user_id}}')].role" == "owner"
+jsonpath "$[?(@.subject.id == '{{bob_user_id}}')].resource.type" == "playlist"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 14c – Bob (Viewer only) is denied on the unified list
+# endpoint: `Share` is required, Viewer's bundle excludes it →
+# 404 anti-enum shape.
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/grants?resource_type=playlist&resource_id={{playlist_id}}
+Authorization: Bearer {{bob_token}}
+
+HTTP 404
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 15 – Alice revokes the ReBAC grant. `DELETE /api/grants/{id}`
+# deletes the single `role_grants` row keyed by grant_id.
+# ─────────────────────────────────────────────────────────────
+DELETE {{base_url}}/api/grants/{{share_grant_id}}
+Authorization: Bearer {{alice_token}}
+
+HTTP 204
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 16 – Bob's GET goes back to 404, and his listing drops the
+# playlist. The `role_grants` row is gone → `list_incoming_grants`
+# doesn't surface it, `require(Read)` denies.
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/playlists/{{playlist_id}}
+Authorization: Bearer {{bob_token}}
+
+HTTP 404
+
+
+GET {{base_url}}/api/playlists?include_shared=true
+Authorization: Bearer {{bob_token}}
+
+HTTP 200
+[Asserts]
+jsonpath "$..id" not contains "{{playlist_id}}"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 17 – Alice re-shares Bob as Editor via the LEGACY endpoint.
+# `can_write=true` maps to `Role::Editor` inside
+# `music_service::share_playlist` — proving the legacy surface
+# and `/api/grants` now converge on the same `role_grants` table.
+# ─────────────────────────────────────────────────────────────
+POST {{base_url}}/api/playlists/{{playlist_id}}/share
+Authorization: Bearer {{alice_token}}
+Content-Type: application/json
+{ "user_id": "{{bob_user_id}}", "can_write": true }
+
+HTTP 204
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 18 – Editor CAN update (Editor's bundle includes Update).
+# Confirms the can_write=true → Editor mapping actually takes
+# effect at the engine level.
+# ─────────────────────────────────────────────────────────────
+PUT {{base_url}}/api/playlists/{{playlist_id}}
+Authorization: Bearer {{bob_token}}
+Content-Type: application/json
+{ "description": "renamed by editor bob" }
+
+HTTP 200
+[Asserts]
+jsonpath "$.description" == "renamed by editor bob"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 19 – Editor still cannot Share (Share stays Owner-only).
+# ─────────────────────────────────────────────────────────────
+POST {{base_url}}/api/playlists/{{playlist_id}}/share
+Authorization: Bearer {{bob_token}}
+Content-Type: application/json
+{ "user_id": "{{alice_user_id}}", "can_write": false }
+
+HTTP 404
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 20 – `/shares` now reports Bob as Editor (can_write=true).
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/playlists/{{playlist_id}}/shares
+Authorization: Bearer {{alice_token}}
+
+HTTP 200
+[Asserts]
+jsonpath "$[*].user_id" contains "{{bob_user_id}}"
+jsonpath "$[?(@.user_id == '{{bob_user_id}}')].can_write" == true
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 21 – Alice removes the legacy-endpoint share.
+# ─────────────────────────────────────────────────────────────
+DELETE {{base_url}}/api/playlists/{{playlist_id}}/share/{{bob_user_id}}
+Authorization: Bearer {{alice_token}}
+
+HTTP 204
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 22 – Post-remove listing is empty (Owner self-grant is
+# still hidden).
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/playlists/{{playlist_id}}/shares
+Authorization: Bearer {{alice_token}}
+
+HTTP 200
+[Asserts]
+jsonpath "$..user_id" not contains "{{bob_user_id}}"
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 23 – Cleanup: Alice deletes the playlist. The service
+# runs `authz.require(Delete)` (owner passes via the seeded Owner
+# grant), then `revoke_all_for_resource` wipes any stray grants.
+# ─────────────────────────────────────────────────────────────
+DELETE {{base_url}}/api/playlists/{{playlist_id}}
+Authorization: Bearer {{alice_token}}
+
+HTTP 204
+
+
+# ─────────────────────────────────────────────────────────────
+# Step 24 – GET returns 404 after delete (nothing to enum).
+# ─────────────────────────────────────────────────────────────
+GET {{base_url}}/api/playlists/{{playlist_id}}
+Authorization: Bearer {{alice_token}}
+
+HTTP 404

tests/api/run.sh

@@ -162,6 +162,7 @@ hurl --variables-file "$API_DIR/test.env" --file-root "$REPO_ROOT/tests" --test
   "$API_DIR/dedup_blob_cleanup.hurl" \
   "$API_DIR/contacts.hurl" \
   "$API_DIR/calendar.hurl" \
+  "$API_DIR/playlists.hurl" \
   "$API_DIR/public_shares.hurl" \
   "$API_DIR/permissions.hurl" \
   "$API_DIR/grants.hurl" \