Web service HTTP headers

The RESTful web services communicate by using the HTTP protocol. Some HTTP headers that need special consideration are described in the following table.

Table 1. HTTP headers that require special consideration
Header	Values	Example	Description
X-CSRF-Protection	Any value. For example, true.	`X-CSRF-Protection: true`	This header is required for manipulating web services when cross-site request forgery (XSRF/CSRF) prevention is enabled.
Accept	`application/json` `application/xml`	`Accept: application/xml`	Specifies whether the response payload data is requested to be in the XML or the JSON representation.
Content-Type	`application/json` `application/xml`	`Content-Type: application/json`	Specifies whether the request payload data is provided in the XML or the JSON representation.
If-None-Match	The `ETag` information can be obtained from an earlier GET operation for a single entity.	`If-None-Match: tsMTTp5rF8zvlUHY83Pk4EXWw==`	If an `If-None-Match` header is included in the request header, the server determines whether the information provided in the `ETag` matches a calculated version of the requested entity. If the information matches, the entity did not change since the last request, and the server returns HTTP status code 304. If the information does not match, the GET request is processed.