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Chapter 4. Entry Point

4.1. Link elements
4.2. Special object elements
4.3. Summary element
A user begins interacting with the API through a GET request on the entry point URI consisting of a {host} and {base}.
GET {base} HTTP/1.1
Host: {host}

HTTP/1.1 200 OK
Link: <http://{host}/{base}/hosts>; rel=hosts, <http://{host}/{base}/vms>; rel=vms
Content-Type: application/xml

    <link rel="hosts" href="{base}/hosts"/>
    <link rel="vms" href="{base}/vms"/>
        <link rel="templates/blank" href="..."/>
        <link rel="tags/root" href="..."/>


For simplicity, all other examples omit the Host request header and assume {base} is the default /rhevm-api. This base path will differ depending on your implementation.

4.1. Link elements

Access to the Entry Point provides the Link header [2] , link elements and URIs for all of the resource collections exposed by the API. Each collection uses a relation type to identify the URI a client needs. The following relation types are available:
Relationship Description
capabilities Information about the supported capabilities of the Red Hat Enterprise Virtualization Manager
datacenters Data centers
clusters Host clusters
networks Virtual networks
storagedomains Storage domains
hosts Hosts
vms Virtual machines
templates Templates
vmpools Virtual machine pools
roles Roles
users Users
domain Identity domain
tags Tags
events Events
statistics Statistics
The relationship between the API entry point and the resource collections exposed by the API
Figure 4.1.  The relationship between the API entry point and the resource collections exposed by the API


All URIs shown in example responses are purely illustrative. The format of all URIs returned by the server is opaque. Clients must navigate to any specific resources through the entry point URI and use the relationship types to access the URIs.
The server may choose to include absolute URIs or absolute paths [3] in the link element href attribute, so clients should be prepared to handle either form. Link headers will only contain absolute URIs.
In addition to the literal URIs described above, the Link header also contains a set of URI templates [4] , which describe the form of URI used for sending search queries to the collections. Each URI template is identified by a relation type, named according to the convention "collection/search".

URI Templates

The purpose of the URI template is to accept a search expression using the natural HTTP pattern of a query parameter. The client does not require prior knowledge of the URI structure. Thus clients should treat these templates as being opaque and instantiate them via a URI template library such as the Google Code uri-templates Python package or the Apache Abdera support for Java templates.
The following relation types are associated with query URI templates:
Relationship Description
datacenters/search Query data centers
clusters/search Query host clusters
storagedomains/search Query storage domains
hosts/search Query hosts
vms/search Query virtual machines
templates/search Query templates
vmpools/search Query virtual machine pools
events/search Query events
users/search Query users

[2] The Internet-Draft describing the format of the Link header is available at
[3] The RFC describing Uniform Resource Locator Generic Syntax provides a Collected ABNF for URI that explains the difference between these forms.
[4] The Internet-Draft describing the format of a URI Template is available at