Chapter 3. Beginner Example

This chapter provides an example to demonstrate the REST API's ability to create a virtual machine within a basic Red Hat Enterprise Virtualization environment.
In addition to the standard prerequisites (see Section 1.2, “Prerequisites”), this example requires the following:
  • A networked and configured host containing Red Hat Enterprise Virtualization Hypervisor;
  • An ISO file containing a desired virtual machine operating system to install. This chapter uses Red Hat Enterprise Linux Server 6 for our installation ISO example; and
  • Red Hat Enterprise Virtualization Platform's uploader tool to upload your chosen operating system ISO file.
This example uses cURL to demonstrate REST requests with a client application. Find out more about cURL use with the REST API in Appendix A, API Usage with cURL. Note that any application capable of HTTP requests can substitute for cURL.

Important

For simplicity, the HTTP request headers in this example omit the Host: and Authorization: fields. However, these fields are mandatory and require data specific to your installation of Red Hat Enterprise Virtualization Manager.

Important

All cURL examples include placeholders for authentication details (USER:PASS) and certificate location (CERT). Ensure all requests performed with cURL fulfil certification and authentication requirements. See Chapter 2, Authentication and Security and Appendix A, API Usage with cURL for more information.

Note

Red Hat Enterprise Virtualization Manager generates a globally unique identifier (GUID) for the id attribute for each resource. Identifier codes in this example might appear different to the identifier codes in your Red Hat Enterprise Virtualization environment.

3.1. Access API Entry Point

The following request retrieves a representation of the main entry point of the API.

Example 3.1. Access the API entry point

GET /api HTTP/1.1
Accept: application/xml
cURL command:
curl -X GET -H "Accept: application/xml" -u [USER:PASS] --cacert [CERT] https://[RHEVM Host]:8443/api
The API returns the following representation:
HTTP/1.1 200 OK
Content-Type: application/xml

<api>
    <link rel="capabilities" href="/api/capabilities"/>
    <link rel="clusters" href="/api/clusters"/>
    <link rel="clusters/search" href="/api/clusters?search={query}"/>
    <link rel="datacenters" href="/api/datacenters"/>
    <link rel="datacenters/search" href="/api/datacenters?search={query}"/>
    <link rel="events" href="/api/events"/>
    <link rel="events/search" href="/api/events?search={query}"/>
    <link rel="hosts" href="/api/hosts"/>
    <link rel="hosts/search" href="/api/hosts?search={query}"/>
    <link rel="networks" href="/api/networks"/>
    <link rel="roles" href="/api/roles"/>
    <link rel="storagedomains" href="/api/storagedomains"/>
    <link rel="storagedomains/search" href="/api/storagedomains?search={query}"/>
    <link rel="tags" href="/api/tags"/>
    <link rel="templates" href="/api/templates"/>
    <link rel="templates/search" href="/api/templates?search={query}"/>
    <link rel="users" href="/api/users"/>
    <link rel="groups" href="/api/groups"/>
    <link rel="domains" href="/api/domains"/>
    <link rel="vmpools" href="/api/vmpools"/>
    <link rel="vmpools/search" href="/api/vmpools?search={query}"/>
    <link rel="vms" href="/api/vms"/>
    <link rel="vms/search" href="/api/vms?search={query}"/>
    <special_objects>
        <link rel="templates/blank"
          href="/api/templates/00000000-0000-0000-0000-000000000000"/>
        <link rel="tags/root"
          href="/api/tags/00000000-0000-0000-0000-000000000000"/>
    </special_objects>
    <product_info>
        <name>Red Hat Enterprise Virtualization</name>
        <vendor>Red Hat</vendor>
        <version revision="0" build="0" minor="0" major="3"/>
    </product_info>
    <summary>
        <vms>
            <total>5</total>
            <active>0</active>
        </vms>
        <hosts>
            <total>1</total>
            <active>1</active>
        </hosts>
        <users>
            <total>1</total>
            <active>1</active>
        </users>
        <storage_domains>
            <total>2</total>
            <active>2</active>
        </storage_domains>
    </summary>
</api>

The entry point provides a user with links to the collections in a virtualization environment. The rel= attribute of each collection link provides a reference point for each link. The next step in this example examines the datacenter collection, which is available through the rel="datacenter" link.
The entry point also contains other data such as product_info, special_objects and summary. This data is covered in chapters outside this example.