Common resource fields

This page describes the common attributes of Arvados resources.


Attribute Type Description Example
uuid string universally unique object identifier, set on create mk2qn-4zz18-w3anr2hk2wgfpuo
owner_uuid string UUID of owner (must be a User or Group), set on create, controls who may access the resource, ownership may be changed explicitly with update, see permission model for details. mk2qn-tpzed-a4lcehql0dv2u25
created_at datetime When resource was created, set on create 2013-01-21T22:17:39Z
modified_by_client_uuid string API client software which most recently modified the resource, set on create and update mk2qn-ozdt8-vq8l5qkzj7pr7h7
modified_by_user_uuid string Authenticated user, on whose behalf the client was acting when modifying the resource, set on create and update mk2qn-tpzed-a4lcehql0dv2u25
modified_at datetime When resource was last modified, set on create and update 2013-01-25T22:29:32Z
href string a URL that can be used to address this resource
kind string arvados#{resource_type} arvados#collection
etag string The ETag1 of the resource 1xlmizzjq7wro3dlb2dirf505

Object UUID

Each object is assigned a UUID. This has the format aaaaa-bbbbb-ccccccccccccccc.

  1. The first field (aaaaa in the example) is the site prefix. This is unique to a specific Arvados installation.
  2. The second field (bbbbb in the example) is the object type.
  3. The third field (ccccccccccccccc in the example) uniquely identifies the object.


All Arvados timestamps follow ISO 8601 datetime format with fractional seconds (microsecond precision). All timestamps are UTC. Date format: YYYY-mm-ddTHH:MM:SS.SSSSZ example date: 2016-11-08T21:38:24.124834000Z.


1 Each response includes an ETag, a string which changes when the resource changes. Clients can use this to check whether a resource has changed since they last retrieved it. If a previous ETag is provided along with a request, and the resource has not changed since, the server may return a “not modified” response.

Previous: Common resource methods Next: Permission model

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Code samples in this documentation are licensed under the Apache License, Version 2.0.