consolidate ResourceNotFoundError sites, fix plurality

llama_stack/providers/inline/files/localfs/files.py

@@ -66,6 +66,18 @@ class LocalfsFilesImpl(Files):
         """Get the filesystem path for a file ID."""
         return Path(self.config.storage_dir) / file_id
 
+    async def _lookup_file_id(self, file_id: str) -> tuple[OpenAIFileObject, Path]:
+        """Look up a OpenAIFileObject and filesystem path from its ID."""
+        if not self.sql_store:
+            raise RuntimeError("Files provider not initialized")
+
+        row = await self.sql_store.fetch_one("openai_files", policy=self.policy, where={"id": file_id})
+        if not row:
+            raise ResourceNotFoundError(file_id, "File", "client.files.list()")
+
+        file_path = Path(row.pop("file_path"))
+        return OpenAIFileObject(**row), file_path
+
     # OpenAI Files API Implementation
     async def openai_upload_file(
         self,
@@ -158,37 +170,19 @@ class LocalfsFilesImpl(Files):
 
     async def openai_retrieve_file(self, file_id: str) -> OpenAIFileObject:
         """Returns information about a specific file."""
-        if not self.sql_store:
-            raise RuntimeError("Files provider not initialized")
+        file_obj, _ = await self._lookup_file_id(file_id)
 
-        row = await self.sql_store.fetch_one("openai_files", policy=self.policy, where={"id": file_id})
-        if not row:
-            raise ResourceNotFoundError(file_id, "files", "files.list()")
-
-        return OpenAIFileObject(
-            id=row["id"],
-            filename=row["filename"],
-            purpose=OpenAIFilePurpose(row["purpose"]),
-            bytes=row["bytes"],
-            created_at=row["created_at"],
-            expires_at=row["expires_at"],
-        )
+        return file_obj
 
     async def openai_delete_file(self, file_id: str) -> OpenAIFileDeleteResponse:
         """Delete a file."""
-        if not self.sql_store:
-            raise RuntimeError("Files provider not initialized")
-
-        row = await self.sql_store.fetch_one("openai_files", policy=self.policy, where={"id": file_id})
-        if not row:
-            raise ResourceNotFoundError(file_id, "files", "files.list()")
-
         # Delete physical file
-        file_path = Path(row["file_path"])
+        _, file_path = await self._lookup_file_id(file_id)
         if file_path.exists():
             file_path.unlink()
 
         # Delete metadata from database
+        assert self.sql_store is not None, "Files provider not initialized"
         await self.sql_store.delete("openai_files", where={"id": file_id})
 
         return OpenAIFileDeleteResponse(
@@ -198,25 +192,15 @@ class LocalfsFilesImpl(Files):
 
     async def openai_retrieve_file_content(self, file_id: str) -> Response:
         """Returns the contents of the specified file."""
-        if not self.sql_store:
-            raise RuntimeError("Files provider not initialized")
-
-        # Get file metadata
-        row = await self.sql_store.fetch_one("openai_files", policy=self.policy, where={"id": file_id})
-        if not row:
-            raise ResourceNotFoundError(file_id, "files", "files.list()")
-
         # Read file content
-        file_path = Path(row["file_path"])
-        if not file_path.exists():
-            raise ResourceNotFoundError(file_id, "files content", "files.list()")
+        file_obj, file_path = await self._lookup_file_id(file_id)
 
-        with open(file_path, "rb") as f:
+        with open(file_path, "rb") as f:  # this may fail and result in 500 Internal Server Error
             content = f.read()
 
         # Return as binary response with appropriate content type
         return Response(
             content=content,
             media_type="application/octet-stream",
-            headers={"Content-Disposition": f'attachment; filename="{row["filename"]}"'},
+            headers={"Content-Disposition": f'attachment; filename="{file_obj.filename}"'},
         )