Querying a Specified API Version

Function Description

This API is used to query the information of a specified version.

To support function extension, Nova APIs can be distinguished by version. There are two types of versions:

Major version: Independent URL
Microversion: Used by the HTTP request header X-OpenStack-Nova-API-Version. Since version 2.27, the new microversion header OpenStack-API-Version has been supported.

If the OpenStack-API-Version request header is used, the version is in the format of "compute microversion".

For example, if key is set to OpenStack-API-Version, set value to compute 2.27.

URI

GET /{api_version}

Table 1 describes the parameters in the URI.

**Table 1** Parameter description
Parameter	Mandatory	Description
api_version	Yes	Specifies an API version, such as V2.

Request

None

Response

The following table describes the response parameters.

**Table 2** Response parameters
Parameter	Type	Description
versions	Object	Specifies the versions. For details, see Table 3.

**Table 3** **versions** field description
Parameter	Type	Description
id	string	Specifies the version ID.
links	Object	Specifies the links to resources. For more information, see the OpenStack Documentation. For details, see Table 4.
media-types	Object	Specifies the media types. For details, see Table 5.
min_version	string	Specifies the microversion. If the APIs of this version support microversions, set this parameter to the supported minimum microversion. If the microversion is not supported, leave this parameter blank.
status	string	Specifies the API version status. Possible values are as follows: CURRENT: This is the preferred API version. SUPPORTED: This is the old API version that is still supported. DEPRECATED: This is the deprecated API version that will be removed.
updated	string	The value of this parameter varies by API version. If the API version is 2.0, the value is 2011-01-21T11:33:21Z. If the API version is 2.1, the value is 2013-07-23T11:33:21Z.
version	string	Specifies the microversion. If the APIs of this version support microversions, set this parameter to the supported maximum microversion. If the microversion is not supported, leave this parameter blank.

**Table 4** **links** field description
Parameter	Type	Description
href	string	Specifies the links of the corresponding resources.
rel	string	self: A self link contains a versioned link to the resource. Use these links when the link is followed immediately. bookmark: A bookmark link provides a permanent link to a resource that is appropriate for long term storage. alternate: An alternate link can contain an alternate representation of the resource. For example, an OpenStack Compute image might have an alternate representation in the OpenStack Image service.

**Table 5** **media-types** field description
Parameter	Type	Description
base	string	Specifies the basic type.
type	string	Specifies the media type.

Example Request

GET https://{endpoint}/v2

Example Response

{
 "version": {
  "min_version": "",
  "media-types": [{
   "type": "application/vnd.openstack.compute+json;version=2",
   "base": "application/json"
  }],
  "links": [{
   "rel": "self",
   "href": "https://ecs.service.domain.com:443/v2/"
  },
  {
   "rel": "describedby",
   "href": "http://docs.openstack.org/",
   "type": "text/html"
  }],
  "id": "v2.0",
  "updated": "1999-02-20T11:33:21Z",
  "version": "",
  "status": "SUPPORTED"
 }
}