examples/domstart.py

   1 #!/usr/bin/env python
   2 # domstart - make sure a given domU is running, if not start it
   3
   4 import libvirt
   5 import sys
   6 import os
   7 import libxml2
   8 import pdb
   9
  10 # Parse the XML description of domU from FNAME
  11 # and return a tuple (name, xmldesc) where NAME
  12 # is the name of the domain, and xmldesc is the contetn of FNAME
  13 def read_domain(fname):
  14     fp = open(fname, "r")
  15     xmldesc = fp.read()
  16     fp.close()
  17
  18     doc = libxml2.parseDoc(xmldesc)
  19     name = doc.xpathNewContext().xpathEval("/domain/name")[0].content
  20     return (name, xmldesc)
  21
  22 def usage():
  23    print('Usage: %s domain.xml' % sys.argv[0])
  24    print('       Check that the domain described by DOMAIN.XML is running')
  25    print('       If the domain is not running, create it')
  26    print('       DOMAIN.XML must be a XML description of the domain')
  27    print('       in libvirt\'s XML format')
  28
  29 if len(sys.argv) != 2:
  30     usage()
  31     sys.exit(2)
  32
  33 (name, xmldesc) = read_domain(sys.argv[1])
  34
  35 conn = libvirt.open(None)
  36 if conn is None:
  37     print('Failed to open connection to the hypervisor')
  38     sys.exit(1)
  39
  40 try:
  41     dom = conn.lookupByName(name)
  42 except libvirt.libvirtError:
  43     print("Starting domain %s ... " % name)
  44     dom = conn.createLinux(xmldesc, 0)
  45     if dom is None:
  46         print("failed")
  47         sys.exit(1)
  48     else:
  49         print("done")