VMware VCLOUD API 1.0 - TECHNICAL NOTE, Руководство по программированию

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Chapter 8 XML Representations in the vCloud API
Link
A Link element defines a hyperlink with a relationship, URI, and an optional name and media type. For more
information about how Link elements are used and a list of the values allowed for the rel attribute, see “Links
and Link Relations” on page 15.
This element is read ‐ only.
API Versioning
vCloud API schema version information appears in the values of the xsi:schemaLocation and xmlns
attributes in a response document. For example, a response body that used schema version 1.0 would include
the following attributes:
xsi:schemaLocation="http://vcloud.example.com/api/v1.0/schema/master.xsd"
xmlns="http://www.vmware.com/vcloud/v1"
To discover the schema versions supported by a server, a client can make an unauthenticated GET request to
a well ‐ known URL on the server, as shown in Example 8 ‐ 2 . The response to this kind of request is a
SupportedVersions document, from which the client can derive information about the media types and
schema locations used by the version of the API that the server supports. The response contains a
MediaTypeMapping element for each media type defined by the API. (The example shows only a few of these
elements.) The response also includes a LoginUrl element, which contains a URL that a client can use to obtain
an authentication token. For more information about using the LoginUrl , see “Authentication” on page 18.
Example 8-2. API Version Request
Request:
GET http://vcloud.example.com/api/versions
Response:
200 OK
Content-Type: text/xml
...
<SupportedVersions ...>
<VersionInfo>
<Version>1</Version>
<LoginUrl>http://vcloud.example.com/api/v1/login</LoginUrl>
<MediaTypeMapping>
<MediaType>application/vnd.vmware.vcloud.org+xml</MediaType>
<ComplexTypeName>CatalogType</ComplexTypeName>
<SchemaLocation>http://vcloud.example.com/api/v1.0/schema/master.xsd</SchemaLocation>
</MediaTypeMapping>
<MediaTypeMapping>
UNKNOWN The request raised an exception that did not match any HTTP status
code.
UNSUPPORTED_MEDIA_TYPE The wrong content type was specified for the request.
Table 8-6. Minor Error Codes (Continued)
Error Code Description of Error
Schema
Name Min Max Type Description
rel 1 1 RelationType Relation of the link to the referenced object
href 1 1 xs:anyURI Hyperlink to the referenced object
type 0 1 xs:string Media type of the referenced object. Links to actions do not
have a media type.
name 0 1 xs:string Name of the referenced object. Links to Tasks and actions
do not have names.