1.5

Table Of Contents
Example: Object id, type, and href Attributes
This XML fragment, extracted from the representation of a vApp, shows its id, type, and href attributes.
<VApp
...
id="urn:vcloud:vapp:490af534-1491-452e-8ed6-a5eb54447dac"
type="application/vnd.vmware.vcloud.vApp+xml"
href="https://vcloud.example.com/api/vApp/vapp-490af534-1491-452e-8ed6-a5eb54447dac"
... >
...
</VApp>
Links and Link Relations
The vCloud API makes extensive use of Link elements to provide references to objects and the actions that
they support. These elements are the primary mechanism by which a server tells a client how to access and
operate on an object.
The server creates Link elements in a response body. They are read-only at the client. If a request body includes
a Link element, the server ignores it.
Attributes of a Link Element
In the XML representation of a vCloud object, each Link element has the following form:
<Link rel="
relationship
"
type="application/vnd.vmware.vcloud.
object_type
+xml"
href="
URL
"
name="
string
"/>
Attribute values in a Link element supply the following information:
rel
Defines the relationship of the link to the object that contains it. A relationship
can be the name of an operation on the object, a reference to a contained or
containing object, or a reference to an alternate representation of the object. The
relationship value implies the HTTP verb to use when you use the link's href
value as a request URL.
type
The object type, specified as a MIME content type, of the object that the link
references. This attribute is present only for links to objects. It is not present for
links to actions.
href
An object reference, expressed in URL format. Because this URL includes the
object identifier portion of the id attribute value, it uniquely identifies the
object, persists for the life of the object, and is never reused. The value of the
href attribute is a reference to a view of the object, and can be used to access a
representation of the object that is valid in a particular context. Although URLs
have a well-known syntax and a well-understood interpretation, a client
should treat each href as an opaque string. The rules that govern how the server
constructs href strings might change in future releases.
name
The name of the referenced object, taken from the value of that object's name
attribute. Action links do not include a name attribute.
vCloud API Programming Guide
12 VMware, Inc.