Implement ownership model for all cached content deletion

- cache_service.delete_content: Remove user's ownership link first,
  only delete actual file if no other owners remain

- cache_manager.discard_activity_outputs_only: Check if outputs and
  intermediates are used by other activities before deleting

- run_service.discard_run: Now cleans up run outputs/intermediates
  (only if not shared by other runs)

- home.py clear_user_data: Use ownership model for effects and media
  deletion instead of directly deleting files

The ownership model ensures:
1. Multiple users can "own" the same cached content
2. Deleting removes the user's ownership link (item_types entry)
3. Actual files only deleted when no owners remain (garbage collection)
4. Shared intermediates between runs are preserved

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/routers/home.py

@@ -132,35 +132,55 @@ async def clear_user_data(request: Request):
     except Exception as e:
         errors.append(f"Failed to list recipes: {e}")
 
-    # Delete all effects
+    # Delete all effects (uses ownership model)
     try:
-        cache_manager = get_cache_manager()
-        effects_dir = Path(cache_manager.cache_dir) / "_effects"
-        if effects_dir.exists():
-            import shutil
-            for effect_dir in effects_dir.iterdir():
-                if effect_dir.is_dir():
-                    try:
-                        shutil.rmtree(effect_dir)
-                        deleted["effects"] += 1
-                    except Exception as e:
-                        errors.append(f"Effect {effect_dir.name}: {e}")
+        # Get user's effects from item_types
+        effect_items = await database.get_user_items(actor_id, item_type="effect", limit=10000)
+        for item in effect_items:
+            cid = item.get("cid")
+            if cid:
+                try:
+                    # Remove ownership link
+                    await database.delete_item_type(cid, actor_id, "effect")
+                    await database.delete_friendly_name(actor_id, cid)
+
+                    # Check if orphaned
+                    remaining = await database.get_item_types(cid)
+                    if not remaining:
+                        # Garbage collect
+                        effects_dir = Path(cache_manager.cache_dir) / "_effects" / cid
+                        if effects_dir.exists():
+                            import shutil
+                            shutil.rmtree(effects_dir)
+                        import ipfs_client
+                        ipfs_client.unpin(cid)
+                    deleted["effects"] += 1
+                except Exception as e:
+                    errors.append(f"Effect {cid[:16]}...: {e}")
     except Exception as e:
         errors.append(f"Failed to delete effects: {e}")
 
-    # Delete all media/cache items for user
+    # Delete all media/cache items for user (uses ownership model)
     try:
-        items = await database.get_user_items(actor_id, limit=10000)
-        for item in items:
-            try:
+        from ..services.cache_service import CacheService
+        cache_service = CacheService(database, cache_manager)
+
+        # Get user's media items (video, image, audio)
+        for media_type in ["video", "image", "audio", "unknown"]:
+            items = await database.get_user_items(actor_id, item_type=media_type, limit=10000)
+            for item in items:
                 cid = item.get("cid")
                 if cid:
-                    await database.delete_cache_item(cid)
-                    deleted["media"] += 1
-            except Exception as e:
-                errors.append(f"Media {item.get('cid', 'unknown')}: {e}")
+                    try:
+                        success, error = await cache_service.delete_content(cid, actor_id)
+                        if success:
+                            deleted["media"] += 1
+                        elif error:
+                            errors.append(f"Media {cid[:16]}...: {error}")
+                    except Exception as e:
+                        errors.append(f"Media {cid[:16]}...: {e}")
     except Exception as e:
-        errors.append(f"Failed to list media: {e}")
+        errors.append(f"Failed to delete media: {e}")
 
     logger.info(f"Cleared data for {actor_id}: {deleted}")
     if errors:

app/services/cache_service.py

@@ -416,32 +416,62 @@ class CacheService:
         return l2_result.get("ipfs_cid") or ipfs_cid, None
 
     async def delete_content(self, cid: str, actor_id: str) -> Tuple[bool, Optional[str]]:
-        """Delete content from cache. Returns (success, error)."""
-        if not self.cache.has_content(cid):
-            return False, "Content not found"
+        """
+        Remove user's ownership link to cached content.
 
-        # Check if pinned
+        This removes the item_types entry linking the user to the content.
+        The cached file is only deleted if no other users own it.
+        Returns (success, error).
+        """
+        import logging
+        logger = logging.getLogger(__name__)
+
+        # Check if pinned for this user
         meta = await self.db.load_item_metadata(cid, actor_id)
         if meta and meta.get("pinned"):
             pin_reason = meta.get("pin_reason", "unknown")
             return False, f"Cannot discard pinned item (reason: {pin_reason})"
 
-        # Check deletion rules via cache_manager
-        can_delete, reason = self.cache.can_delete(cid)
-        if not can_delete:
-            return False, f"Cannot discard: {reason}"
+        # Get the item type to delete the right ownership entry
+        item_types = await self.db.get_item_types(cid, actor_id)
+        if not item_types:
+            return False, "You don't own this content"
 
-        # Delete via cache_manager
-        success, msg = self.cache.delete_by_cid(cid)
+        # Remove user's ownership links (all types for this user)
+        for item in item_types:
+            item_type = item.get("type", "media")
+            await self.db.delete_item_type(cid, actor_id, item_type)
 
-        # Clean up legacy metadata files
-        meta_path = self.cache_dir / f"{cid}.meta.json"
-        if meta_path.exists():
-            meta_path.unlink()
-        mp4_path = self.cache_dir / f"{cid}.mp4"
-        if mp4_path.exists():
-            mp4_path.unlink()
+        # Remove friendly name
+        await self.db.delete_friendly_name(actor_id, cid)
 
+        # Check if anyone else still owns this content
+        remaining_owners = await self.db.get_item_types(cid)
+
+        # Only delete the actual file if no one owns it anymore
+        if not remaining_owners:
+            # Check deletion rules via cache_manager
+            can_delete, reason = self.cache.can_delete(cid)
+            if can_delete:
+                # Delete via cache_manager
+                self.cache.delete_by_cid(cid)
+
+                # Clean up legacy metadata files
+                meta_path = self.cache_dir / f"{cid}.meta.json"
+                if meta_path.exists():
+                    meta_path.unlink()
+                mp4_path = self.cache_dir / f"{cid}.mp4"
+                if mp4_path.exists():
+                    mp4_path.unlink()
+
+                # Delete from database
+                await self.db.delete_cache_item(cid)
+
+                logger.info(f"Garbage collected content {cid[:16]}... (no remaining owners)")
+            else:
+                logger.info(f"Content {cid[:16]}... orphaned but cannot delete: {reason}")
+
+        logger.info(f"Removed content {cid[:16]}... ownership for {actor_id}")
         return True, None
 
     async def import_from_ipfs(self, ipfs_cid: str, actor_id: str) -> Tuple[Optional[str], Optional[str]]:

app/services/run_service.py

@@ -467,10 +467,13 @@ class RunService:
         username: str,
     ) -> Tuple[bool, Optional[str]]:
         """
-        Discard (delete) a run record.
+        Discard (delete) a run record and clean up outputs/intermediates.
 
-        Note: This removes the run record but not the output content.
+        Outputs and intermediates are only deleted if not used by other runs.
         """
+        import logging
+        logger = logging.getLogger(__name__)
+
         run = await self.get_run(run_id)
         if not run:
             return False, f"Run {run_id} not found"
@@ -480,6 +483,18 @@ class RunService:
         if run_owner and run_owner not in (username, actor_id):
             return False, "Access denied"
 
+        # Clean up activity outputs/intermediates (only if orphaned)
+        # The activity_id is the same as run_id
+        try:
+            success, msg = self.cache.discard_activity_outputs_only(run_id)
+            if success:
+                logger.info(f"Cleaned up run {run_id}: {msg}")
+            else:
+                # Activity might not exist (old runs), that's OK
+                logger.debug(f"No activity cleanup for {run_id}: {msg}")
+        except Exception as e:
+            logger.warning(f"Failed to cleanup activity for {run_id}: {e}")
+
         # Remove task_id mapping from Redis
         self.redis.delete(f"{self.task_key_prefix}{run_id}")
 
@@ -487,8 +502,7 @@ class RunService:
         try:
             await self.db.delete_run_cache(run_id)
         except Exception as e:
-            import logging
-            logging.getLogger(__name__).warning(f"Failed to delete run_cache for {run_id}: {e}")
+            logger.warning(f"Failed to delete run_cache for {run_id}: {e}")
 
         # Remove pending run if exists
         try:

cache_manager.py

@@ -690,11 +690,26 @@ class L1CacheManager:
             return True, "Activity discarded"
         return False, "Failed to discard"
 
+    def _is_used_by_other_activities(self, node_id: str, exclude_activity_id: str) -> bool:
+        """Check if a node is used by any activity other than the excluded one."""
+        for other_activity in self.activity_store.list():
+            if other_activity.activity_id == exclude_activity_id:
+                continue
+            # Check if used as input, output, or intermediate
+            if node_id in other_activity.input_ids:
+                return True
+            if node_id == other_activity.output_id:
+                return True
+            if node_id in other_activity.intermediate_ids:
+                return True
+        return False
+
     def discard_activity_outputs_only(self, activity_id: str) -> tuple[bool, str]:
         """
         Discard an activity, deleting only outputs and intermediates.
 
         Inputs (cache items, configs) are preserved.
+        Outputs/intermediates used by other activities are preserved.
 
         Returns:
             (success, message) tuple
@@ -711,21 +726,31 @@ class L1CacheManager:
                 if pinned:
                     return False, f"Output is pinned ({reason})"
 
-        # Delete output
-        if activity.output_id:
-            entry = self.cache.get_entry(activity.output_id)
-            if entry:
-                # Remove from cache
-                self.cache.remove(activity.output_id)
-                # Remove from content index (Redis + local)
-                self._del_content_index(entry.cid)
-                # Delete from legacy dir if exists
-                legacy_path = self.legacy_dir / entry.cid
-                if legacy_path.exists():
-                    legacy_path.unlink()
+        deleted_outputs = 0
+        preserved_shared = 0
 
-        # Delete intermediates
+        # Delete output (only if not used by other activities)
+        if activity.output_id:
+            if self._is_used_by_other_activities(activity.output_id, activity_id):
+                preserved_shared += 1
+            else:
+                entry = self.cache.get_entry(activity.output_id)
+                if entry:
+                    # Remove from cache
+                    self.cache.remove(activity.output_id)
+                    # Remove from content index (Redis + local)
+                    self._del_content_index(entry.cid)
+                    # Delete from legacy dir if exists
+                    legacy_path = self.legacy_dir / entry.cid
+                    if legacy_path.exists():
+                        legacy_path.unlink()
+                    deleted_outputs += 1
+
+        # Delete intermediates (only if not used by other activities)
         for node_id in activity.intermediate_ids:
+            if self._is_used_by_other_activities(node_id, activity_id):
+                preserved_shared += 1
+                continue
             entry = self.cache.get_entry(node_id)
             if entry:
                 self.cache.remove(node_id)
@@ -733,11 +758,16 @@ class L1CacheManager:
                 legacy_path = self.legacy_dir / entry.cid
                 if legacy_path.exists():
                     legacy_path.unlink()
+                deleted_outputs += 1
 
         # Remove activity record (inputs remain in cache)
         self.activity_store.remove(activity_id)
 
-        return True, "Activity discarded (outputs only)"
+        msg = f"Activity discarded (deleted {deleted_outputs} outputs"
+        if preserved_shared > 0:
+            msg += f", preserved {preserved_shared} shared items"
+        msg += ")"
+        return True, msg
 
     def cleanup_intermediates(self) -> int:
         """Delete all intermediate cache entries (reconstructible)."""