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<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook V4.2//EN" [

<!ENTITY JsonLink "http://www.json.org/">

<!ENTITY WikipediaRESTLink

  "http://en.wikipedia.org/wiki/Representational_State_Transfer">

]>

<article class="specification">

<articleinfo>

  <title>Ganeti remote API</title>

</articleinfo>

<para>Documents Ganeti version 1.2</para>

<sect1>

  <title>Introduction</title>

  <para>Ganeti supports a remote API for enable external tools to easily

    retrieve information about a cluster's state. The remote API daemon,

    <computeroutput>ganeti-rapi</computeroutput>, is automatically started on

    the master node if the <computeroutput>--enable-rapi</computeroutput>

    parameter is passed to the <computeroutput>configure</computeroutput>

    script. Alternatively you can start it manually. By default it runs on TCP

    port 5080, but this can be changed either in

    <filename>&hellip;/constants.py</filename> or via the command line

    parameter <computeroutput>-p</computeroutput>. SSL support can also be

    enabled by passing command line parameters.</para>

  <note>

    <para>Ganeti 1.2 only supports a limited set of calls, all of them

      read-only. The next major version will have support for write

      operations.</para>

  </note>

</sect1>

<sect1>

  <title>Protocol</title>

  <para>The protocol used is <ulink url="&JsonLink;">JSON</ulink> over HTTP

    designed after the <ulink url="&WikipediaRESTLink;">REST</ulink> principle.

  </para>

</sect1>

<sect1>

  <title>Usage examples</title>

  <para>You can access the API using your favorite programming language as long

    as it supports network connections.</para>

  <sect2>

    <title>Shell</title>

    <screen>wget -q -O - http://<replaceable>CLUSTERNAME</replaceable>:5080/info</screen>

  </sect2>

  <sect2>

    <title>Python</title>

    <screen>import urllib2

f = urllib2.urlopen('http://<replaceable>CLUSTERNAME</replaceable>:5080/info')

print f.read()</screen>

  </sect2>

  <sect2>

    <title>JavaScript</title>

    <note>

      <para>While it's possible to use JavaScript, it poses several potential

        problems, including browser blocking request due to non-standard ports

        or different domain names. Fetching the data on the webserver is

        easier.</para>

    </note>

    <screen>var url = 'http://<replaceable>CLUSTERNAME</replaceable>:5080/info';

var info;

var xmlreq = new XMLHttpRequest();

xmlreq.onreadystatechange = function () {

  if (xmlreq.readyState != 4) return;

  if (xmlreq.status == 200) {

    info = eval("(" + xmlreq.responseText + ")");

    alert(info);

  } else {

    alert('Error fetching cluster info');

  }

  xmlreq = null;

};

xmlreq.open('GET', url, true);

xmlreq.send(null);</screen>

  </sect2>

</sect1>

<sect1>

  <title>Resources</title>

  @INCLUDE_RAPI_RESOURCES@

</sect1>

</article>