These are the headers that are common to all Riak CS REST requests.

Authorization - Information required to request authentication. This header is not required for anonymous requests.

Content-Length - Length of message without headers according to RFC 2616. This header is required for PUTs and operations that load XML.

Content-Type - The content type of the resource.

Content-MD5 - The base64-encoded 128-bit MD5 digest of the message without the headers according to RFC 1864. Although this header is optional, the Content-MD5 header can be used to confirm that the data is the same as what was originally sent.

Date - The current data and time according to the requester, for example, Fri, 01 Jun 2012 12:00:00 GMT. With the Authorization header, you must specify either x-amz-date or Date header.

Expect - When you use 100-continue in your application, it doesn't send the request body until it receives an acknowledgment. That way, the body of the message isn't sent if the message is rejected based on the headers.

• Valid Values: 100-continue

Host - For path-style requests, the value is something like data.basho.com. For virtual-style requests, the value is something like bucketname.data.basho.com.

This header is optional for HTTP/1.0 requests, but is required for HTTP 1.1.

x-amz-date - The current data and time according to the requester, for example, Fri, 01 Jun 2012 12:00:00 GMT. With the Authorization header, you must specify either x-amz-date or Date header. If you specify both, the value for this header takes precedence.