---
layout: default
navsection: api
title: "Resource: Collections"
navorder: 10
---

h1. Collections

This resource concerns metadata, usage accounting, and integrity checks for data stored on the cloud.  Reading and writing the data _per se_ is achieved by the "Keep":{{ baseurl }}/user/intro-keep.html storage system.


h2. Methods

See "REST methods for working with Arvados resources":methods.html

API endpoint base: @https://{{ site.arvados_api_host }}/arvados/v1/links@

h3. Conditions of creating a Collection

The @uuid@ and @manifest_text@ attributes must be provided when creating a Collection. The cryptographic digest of the supplied @manifest_text@ must match the supplied @uuid@.

h3. Side effects of creating a Collection

Referenced data can be protected from garbage collection.

Data can be shared with other users via the Arvados permission model.

Clients can request checks of data integrity and storage redundancy.

h2. Resource

Each collection has, in addition to the usual "attributes of Arvados resources":resources.html:

table(table table-bordered table-condensed).
|*Property name*|*Value*|*Description*|
|portable_data_hash|string||
|redundancy|number||
|redundancy_confirmed_by_client_uuid|string|API client|
|redundancy_confirmed_at|datetime||
|redundancy_confirmed_as|number||