Riak CS Storage API

The Riak CS storage API is compatible with the Amazon S3 REST API, which means that any of the operations listed can be executed using any of the commonly available S3 libraries or tools.

API Feature Comparison

The following table describes the support status for current Amazon S3 functional features.

Feature Status Remark
GET Service (lists all buckets for authenticated user)
PUT Bucket
Bucket Lifecycle
Policy (Buckets, Objects) {{1.3.0+}} Supports the “*” principal type and the “Secure Transport” and “IP address” conditions.
Policy (Buckets, Objects) {{1.3.0-}} Coming Soon Planned for future release
Bucket Website
Bucket ACLs (GET, PUT)
Bucket Location
Bucket Notification
Bucket Object Versions
GET Bucket Info (HEAD)
Bucket Request Payment
PUT Object
Put Object (Copy) {{1.5.0+}}
PUT Object (Copy) {{1.3.0-1.5.0}} Support is limited to a 0 byte copy from an object to itself for the purpose of updating metadata.
PUT Object (Copy) {{1.3.0-}} Coming Soon Planned for future release
DELETE Object {{1.3.0-}}
DELETE Multiple Objects Planned for future release
GET Object {{1.3.0+}}
GET Object {{1.3.0-}} Range query unimplemented
Object ACLs (GET, PUT)
HEAD Object
POST Object
Copy Object Planned for future release
Multipart Uploads {{1.3.0+}} UploadPartCopy unimplemented
Multipart Uploads {{1.3.0-}} Coming Soon Planned for future release

Service-level Operations

  • GET Service — Returns a list of all buckets owned by the user who sent the request

Bucket-level Operations

Object-level Operations

Multipart Upload

Multipart upload allows you to upload a single object as a set of parts. Object parts can be uploaded independently and in any order. After all parts are uploaded, Riak CS assembles an object out of the parts. When your object size reaches 100MB, you should consider using multipart uploads instead of uploading the object in a single operation. Read more about multipart uploads on the overview page.

Common Headers

There are two storage API options for Riak CS. The first and most fully featured is the S3 API. There is also limited but improving support for the OpenStack Object Storage API.

Riak CS can present different APIs by using the URL-rewriting capabilities of Webmachine. Configuring what API Riak CS uses is done by specifying the proper rewrite module in the configuration file. A rewrite module contains a set of rules for translating requests made using a particular API to requests in the native Riak CS API. The native API was designed to facilitate the organization and maintenance of the Riak CS Webmachine resource modules.


Openstack Object Storage API (v1)

Selecting an API is done by adding or changing the rewrite_module key in the Riak CS riak-cs.conf file, or the old-style advanced.config or app.config files in the riak_cs section. For example, to instruct Riak CS to present the S3 API, ensure the following is contained in your configuration file:

rewrite_module = riak_cs_s3_rewrite
 {riak_cs, [
            %% Other configs
            {rewrite_module, riak_cs_s3_rewrite},
            %% Other configs
 {riak_cs, [
            %% Other configs
            {rewrite_module, riak_cs_s3_rewrite},
            %% Other configs

The S3 API is the default that is set in the configuration that is included when installing a Riak CS package or building from source.

More details for each option can be found by following one of the following links: