---
layout: default
navsection: api
navmenu: API Methods
title: "collections"

...

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

Object type: @4zz18@

Example UUID: @zzzzz-4zz18-0123456789abcde@

h2. Resource

Collections describe sets of files in terms of data blocks stored in Keep.  See "storage in Keep":{{site.baseurl}}/api/storage.html for details.

Each collection has, in addition to the "Common resource fields":{{site.baseurl}}/api/resources.html:

table(table table-bordered table-condensed).
|_. Attribute|_. Type|_. Description|_. Example|
|name|string|||
|description|text|||
|portable_data_hash|string|The MD5 sum of the manifest text stripped of block hints other than the size hint.||
|manifest_text|text|||
|replication_desired|number|Minimum storage replication level desired for each data block referenced by this collection. A value of @null@ signifies that the site default replication level (typically 2) is desired.|@2@|
|replication_confirmed|number|Replication level most recently confirmed by the storage system. This field is null when a collection is first created, and is reset to null when the manifest_text changes in a way that introduces a new data block. An integer value indicates the replication level of the _least replicated_ data block in the collection.|@2@, null|
|replication_confirmed_at|datetime|When replication_confirmed was confirmed. If replication_confirmed is null, this field is also null.||

h3. Conditions of creating a Collection

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

h3. Side effects of creating a Collection

Referenced blocks are protected from garbage collection in Keep.

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

h2. Methods

See "Common resource methods":{{site.baseurl}}/api/methods.html for more information about @create@, @delete@, @get@, @list@, and @update@.

Required arguments are displayed in %{background:#ccffcc}green%.

h3. create

Create a new Collection.

Arguments:

table(table table-bordered table-condensed).
|_. Argument |_. Type |_. Description |_. Location |_. Example |
|collection|object||query||

h3. delete

Delete an existing Collection.

Arguments:

table(table table-bordered table-condensed).
|_. Argument |_. Type |_. Description |_. Location |_. Example |
{background:#ccffcc}.|uuid|string|The UUID of the Collection in question.|path||

h3. get

Gets a Collection's metadata by UUID.

Arguments:

table(table table-bordered table-condensed).
|_. Argument |_. Type |_. Description |_. Location |_. Example |
{background:#ccffcc}.|uuid|string|The UUID of the Collection in question.|path||

h3. list

List collections.

See "common resource list method.":{{site.baseurl}}/api/methods.html#index

Note: Because adding access tokens to manifests can be computationally expensive, the @manifest_text@ field is not included in results by default.  If you need it, pass a @select@ parameter that includes @manifest_text@.

h3. update

Update attributes of an existing Collection.

Arguments:

table(table table-bordered table-condensed).
|_. Argument |_. Type |_. Description |_. Location |_. Example |
{background:#ccffcc}.|uuid|string|The UUID of the Collection in question.|path||
|collection|object||query||