Avatars = new FS.Collection('avatars', { stores: [new FS.Store.GridFS('avatars')], filter: { maxSize: 72000, allow: { contentTypes: ['image/*'], }, }, }); function isOwner(userId, file) { return userId && userId === file.userId; } Avatars.allow({ insert: isOwner, update: isOwner, remove: isOwner, download() { return true; }, fetch: ['userId'], }); Avatars.files.before.insert((userId, doc) => { doc.userId = userId; }); export default Avatars;