mirror of
https://gitlab.com/libvirt/libvirt.git
synced 2024-12-27 16:15:23 +00:00
168 lines
8.4 KiB
HTML
168 lines
8.4 KiB
HTML
<?xml version="1.0" encoding="ISO-8859-1"?>
|
|
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
|
|
<html xmlns="http://www.w3.org/1999/xhtml">
|
|
<!--
|
|
This file is autogenerated from python.html.in
|
|
Do not edit this file. Changes will be lost.
|
|
-->
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" />
|
|
<link rel="stylesheet" type="text/css" href="main.css" />
|
|
<link rel="SHORTCUT ICON" href="32favicon.png" />
|
|
<title>libvirt: Python API bindings</title>
|
|
<meta name="description" content="libvirt, virtualization, virtualization API" />
|
|
</head>
|
|
<body>
|
|
<div id="header">
|
|
<div id="headerLogo"></div>
|
|
<div id="headerSearch">
|
|
<form action="search.php" enctype="application/x-www-form-urlencoded" method="get"><div>
|
|
<input id="query" name="query" type="text" size="12" value="" />
|
|
<input id="submit" name="submit" type="submit" value="Search" />
|
|
</div></form>
|
|
</div>
|
|
</div>
|
|
<div id="body">
|
|
<div id="menu">
|
|
<ul class="l0"><li>
|
|
<div>
|
|
<a title="Front page of the libvirt website" class="inactive" href="index.html">Home</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="Details of new features and bugs fixed in each release" class="inactive" href="news.html">News</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="Get the latest source releases, binary builds and get access to the source repository" class="inactive" href="downloads.html">Downloads</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="Information for users, administrators and developers" class="active" href="docs.html">Documentation</a>
|
|
<ul class="l1"><li>
|
|
<div>
|
|
<a title="Information about deploying and using libvirt" class="inactive" href="deployment.html">Deployment</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="Overview of the logical subsystems in the libvirt API" class="inactive" href="intro.html">Architecture</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="Description of the XML formats used in libvirt" class="inactive" href="format.html">XML format</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="Hypervisor specific driver information" class="inactive" href="drivers.html">Drivers</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="Reference manual for the C public API" class="inactive" href="html/index.html">API reference</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="Bindings of the libvirt API for other languages" class="active" href="bindings.html">Language bindings</a>
|
|
<ul class="l2"><li>
|
|
<div>
|
|
<span class="active">Python</span>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="overview of the Java API bindings" class="inactive" href="java.html">Java</a>
|
|
</div>
|
|
</li></ul>
|
|
</div>
|
|
</li></ul>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="User contributed content" class="inactive" href="http://wiki.libvirt.org">Wiki</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="Frequently asked questions" class="inactive" href="FAQ.html">FAQ</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="How and where to report bugs and request features" class="inactive" href="bugs.html">Bug reports</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="How to contact the developers via email and IRC" class="inactive" href="contact.html">Contact</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="Miscellaneous links of interest related to libvirt" class="inactive" href="relatedlinks.html">Related Links</a>
|
|
</div>
|
|
</li><li>
|
|
<div>
|
|
<a title="Overview of all content on the website" class="inactive" href="sitemap.html">Sitemap</a>
|
|
</div>
|
|
</li></ul>
|
|
</div>
|
|
<div id="content">
|
|
<h1>Python API bindings</h1>
|
|
<p>The Python binding should be complete and are mostly automatically
|
|
generated from the formal description of the API in xml. The bindings are
|
|
articulated around 2 classes <code>virConnect</code> and virDomain mapping to
|
|
the C types. Functions in the C API taking either type as argument then
|
|
becomes methods for the classes, their name is just stripped from the
|
|
virConnect or virDomain(Get) prefix and the first letter gets converted to
|
|
lower case, for example the C functions:</p>
|
|
<p>
|
|
<code>int <a href="html/libvirt-libvirt.html#virConnectNumOfDomains">virConnectNumOfDomains</a>
|
|
(virConnectPtr conn);</code>
|
|
</p>
|
|
<p>
|
|
<code>int <a href="html/libvirt-libvirt.html#virDomainSetMaxMemory">virDomainSetMaxMemory</a>
|
|
(virDomainPtr domain, unsigned long memory);</code>
|
|
</p>
|
|
<p>become</p>
|
|
<p>
|
|
<code>virConn::numOfDomains(self)</code>
|
|
</p>
|
|
<p>
|
|
<code>virDomain::setMaxMemory(self, memory)</code>
|
|
</p>
|
|
<p>This process is fully automated, you can get a summary of the conversion
|
|
in the file libvirtclass.txt present in the python dir or in the docs.There
|
|
is a couple of function who don't map directly to their C counterparts due to
|
|
specificities in their argument conversions:</p>
|
|
<ul><li><code><a href="html/libvirt-libvirt.html#virConnectListDomains">virConnectListDomains</a></code>
|
|
is replaced by <code>virDomain::listDomainsID(self)</code> which returns
|
|
a list of the integer ID for the currently running domains</li><li><code><a href="html/libvirt-libvirt.html#virDomainGetInfo">virDomainGetInfo</a></code>
|
|
is replaced by <code>virDomain::info()</code> which returns a list of
|
|
<ol><li>state: one of the state values (virDomainState)</li><li>maxMemory: the maximum memory used by the domain</li><li>memory: the current amount of memory used by the domain</li><li>nbVirtCPU: the number of virtual CPU</li><li>cpuTime: the time used by the domain in nanoseconds</li></ol></li></ul>
|
|
<p>So let's look at a simple example inspired from the <code>basic.py</code>
|
|
test found in <code>python/tests/</code> in the source tree:</p>
|
|
<pre>import <span style="color: #0071FF; background-color: #FFFFFF">libvirt</span>
|
|
import sys
|
|
|
|
conn = <span style="color: #0071FF; background-color: #FFFFFF">libvirt</span>.openReadOnly(None)
|
|
if conn == None:
|
|
print 'Failed to open connection to the hypervisor'
|
|
sys.exit(1)
|
|
|
|
try:
|
|
dom0 = conn.<span style="color: #007F00; background-color: #FFFFFF">lookupByName</span>("Domain-0")
|
|
except:
|
|
print 'Failed to find the main domain'
|
|
sys.exit(1)
|
|
|
|
print "Domain 0: id %d running %s" % (dom0.<span style="color: #FF0080; background-color: #FFFFFF">ID</span>(), dom0.<span style="color: #FF0080; background-color: #FFFFFF">OSType</span>())
|
|
print dom0.<span style="color: #FF0080; background-color: #FFFFFF">info</span>()</pre>
|
|
<p>There is not much to comment about it, it really is a straight mapping
|
|
from the C API, the only points to notice are:</p>
|
|
<ul><li>the import of the module called <code><span style="color: #0071FF; background-color: #FFFFFF">libvirt</span></code></li><li>getting a connection to the hypervisor, in that case using the
|
|
openReadOnly function allows the code to execute as a normal user.</li><li>getting an object representing the Domain 0 using <span style="color: #007F00; background-color: #FFFFFF">lookupByName</span></li><li>if the domain is not found a libvirtError exception will be raised</li><li>extracting and printing some information about the domain using
|
|
various <span style="color: #E50073; background-color: #FFFFFF">methods</span>
|
|
associated to the virDomain class.</li></ul>
|
|
</div>
|
|
</div>
|
|
<div id="footer">
|
|
<p id="sponsor">
|
|
Sponsored by:<br /><a href="http://et.redhat.com/"><img src="et.png" alt="Project sponsored by Red Hat Emerging Technology" /></a></p>
|
|
</div>
|
|
</body>
|
|
</html>
|