API Guide

is no sufficient privileges. In other cases, some of the properties in certain resource may not be returned in a response. The service
may also return errors when such properties are modified. For information of specific license requirements for the resources, see
Redfish Resources.
HTTP Methods
The REST API allows you to specify the type of request. It adheres to the Create, Retrieve, Update, and Delete (CRUD) standard
format. The data is generated via access to URIs, which can be accessed by using the following HTTP methods:
• GET
• POST
• PUT
• PATCH
• DELETE
GET
Use the GET method to retrieve a representation of a resource. The representation can either be a single resource or a collection.
The service returns the resource representation by using one of the media types specified in the Accept header depending on the
media type requirement. If the Accept header is not present, the service returns the resource representations in the expected
format either as application/json or application/xml. The formats are supported by that resource as per the Redfish standard.
The HTTP GET method is used to retrieve a resource without causing any side effects. The service ignores the content of the body
on a GET. The GET operation is unchanged in the absence of external changes to the resource.
POST
Use the POST method to invoke actions and create a new resource. The POST request is submitted to the resource collection in
which the new resource belongs. Submitting a POST request to a resource representing a collection is equivalent to submitting the
same request to the Members property of that resource. Services that support adding members to a collection support both forms.
Services support the POST method for creating resources. If the resource does not support this, status code 405 is returned. The
body of the create request contains a representation of the object to be created. The service can ignore any service controlled
attributes such as ID, forcing those attributes for the service to be overridden. The service sets the Location header to the URI of
the newly created resource. The response to a successful create request is status code 201, which indicates the new resource has
been created and includes a response body containing the representation of the newly created resource.
PUT
Use the PUT method to replace the property values of a resource completely. Properties omitted from the request body are reset
to their default value. Services support the PUT method to replace a resource completely. If a service does not implement this
method, status code 405 is returned. Services may return a representation of the resource after any server-side transformations
occur in the body of the response. The PUT operation must be unchanged in the absence of external changes to the resource, with
the exception that the ETag values may change as a result of this operation.
PATCH
The PATCH method is the preferred method, which is used to perform updates on pre-existing resources. Changes to the resource
are sent in the request body. The PATCH request does not change the properties that are not specified in the request body. The
response is either empty or a representation of the resource after the update is done or a success code if the operation is done
successfully.. The implementation may reject the update operation on certain fields based on its own policies and does not apply any
of the requested updates.
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