4.5. RESTful Service Description Language (RSDL)

RESTful Service Description Language (RSDL) provides a description of the structure and elements in the REST API in one whole XML specification. Invoke the RSDL using the following request. 
GET /api?rsdl HTTP/1.1
Accept: application/xml
This produces an XML document in the following format: 
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<rsdl href="/api?rsdl" rel="rsdl">
    <description>...</description>
    <version major="3" minor="1" build="0" revision="0"/>
    <schema href="/api?schema" rel="schema">
        <name>...</name>
        <description>...</description>
    </schema>
    <links>
        <link href="/api/capabilities" rel="get">
            ...
        </link>
        ...
    </links>
</rsdl>

Table 4.5. RSDL Structure Elements

Element Description
description A plain text description of the RSDL document.
version The API version, including major release, minor release, build and revision.
schema A link to the XML schema (XSD) file.
links Defines each link in the API.
Each link element contains the following a structure: 
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<rsdl href="/api?rsdl" rel="rsdl">
    ...
    <links>
        <link href="/api/..." rel="...">
            <request>
                <http_method>...</http_method>
                <headers>
                    <header>
                        <name>...</name>
                        <value>...</value>
                    </header>
                    ...
                </headers>
                <body>
                    <type>...</type>
                    <parameters_set>
                        <parameter required="..." type="...">
                            <name>...</name>
                        </parameter>
                        ...
                    </parameters_set>
                </body>
            </request>
            <response>
                <type>...</type>
            </response>
        </link>
        ...
    </links>
</rsdl>

Table 4.6. RSDL Link Structure Elements

Element Description
link A URI for API requests. Includes a URI attribute (href) and a relationship type attribute (rel).
request Defines the request properties required for the link.
http_method The method type to access this link. Includes the standard HTTP methods for REST API access: GET, POST, PUT and DELETE.
headers Defines the headers for the HTTP request. Contains a series of header elements, which each contain a header name and value to define the header.
body Defines the body for the HTTP request. Contains a resource type and a parameter_set, which contains a sets of parameter elements with attributes to define whether they are required for a request and the data type. The parameter element also includes a name element to define the Red Hat Enterprise Virtualization Manager property to modify and also a further parameter_set subset if type is set to collection.
response Defines the output for the HTTP request. Contains a type element to define the resource structure to output.
Use the RSDL in your applications as a method to map all links and parameter requirements for controlling a Red Hat Enterprise Virtualization environment.