5:49 a.m.
From: Radek Pazdera <rpazdera(a)redhat.com>
This commit adds VirtUtils module to Common.
VirtUtils is a set of classes that can be used to manage virtual
domains and networks.
VirtDomainCtl can control libvirt domains,
VirtNetCtl can control libvirt networks,
BridgeCtl can control network bridges.
Signed-off-by: Radek Pazdera <rpazdera(a)redhat.com>
---
Common/VirtUtils.py | 242 +++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 242 insertions(+), 0 deletions(-)
create mode 100644 Common/VirtUtils.py
diff --git a/Common/VirtUtils.py b/Common/VirtUtils.py
new file mode 100644
index 0000000..28a3d7e
--- /dev/null
+++ b/Common/VirtUtils.py
@@ -0,0 +1,242 @@
+"""
+Utilities for manipulating virtualization host, its guests and
+connections between them
+
+Copyright 2012 Red Hat, Inc.
+Licensed under the GNU General Public License, version 2 as
+published by the Free Software Foundation; see COPYING for details.
+"""
+
+__author__ = """
+rpazdera(a)redhat.com (Radek Pazdera)
+"""
+
+import os
+import re
+import copy
+import time
+import logging
+from tempfile import NamedTemporaryFile
+from xml.dom import minidom
+from ExecCmd import exec_cmd, ExecCmdFail
+from Common.NetUtils import normalize_hwaddr, scan_netdevs
+
+class VirtUtilsError(Exception):
+ pass
+
+def _ip(cmd):
+ try:
+ exec_cmd("ip %s" % cmd)
+ except ExecCmdFail as err:
+ raise VirtUtilsError("ip command error: %s" % err)
+
+def _brctl(cmd):
+ try:
+ exec_cmd("brctl %s" % cmd)
+ except ExecCmdFail as err:
+ raise VirtUtilsError("brctl error: %s" % err)
+
+def _virsh(cmd):
+ try:
+ exec_cmd("virsh %s" % cmd)
+ except ExecCmdFail as err:
+ raise VirtUtilsError("virsh error: %s" % err)
+
+
+class VirtDomainCtl:
+ _name = None
+
+ def __init__(self, domain_name):
+ self._name = domain_name
+
+ def start(self):
+ _virsh("start %s" % self._name)
+
+ def stop(self):
+ _virsh("destroy %s" % self._name)
+
+ def restart(self):
+ _virsh("reboot %s" % self._name)
+
+ def attach_interface(self, hwaddr, net_name, net_type="bridge"):
+ _virsh("attach-interface %s %s %s --mac %s" % \
+ (self._name, net_type, net_name, hwaddr))
+ self.ifup(hwaddr)
+
+ def detach_interface(self, hwaddr, net_type="bridge"):
+ _virsh("detach-interface %s %s %s" % (self._name, net_type, hwaddr))
+
+ def ifup(self, hwaddr):
+ _virsh("domif-setlink %s %s up" % (self._name, hwaddr))
+
+ def ifdown(self, hwaddr):
+ _virsh("domif-setlink %s %s down" % (self._name, hwaddr))
+
+class NetCtl(object):
+ _name = None
+
+ def __init__(self, name):
+ self._name = name
+
+ def get_name(self):
+ return self._name
+
+ def init(self):
+ pass
+
+ def cleanup(self):
+ pass
+
+class VirtNetCtl(NetCtl):
+ _addr = None
+ _mask = None
+
+ _dhcp_from = None
+ _dhcp_to = None
+ _static_mappings = []
+ _lease_file = None
+
+ def setup_dhcp_server(self, addr, mask, range_start, range_end,
+ static_map=None):
+ self._addr = addr
+ self._mask = mask
+ self._dhcp_from = range_start
+ self._dhcp_to = range_end
+ self._lease_file = "/var/lib/libvirt/dnsmasq/%s.leases" % self._name
+ if static_map:
+ self._static_mappings = static_map
+
+ def get_dhcp_mapping(self, hwaddr, timeout=30):
+ wait = timeout
+ while True:
+ addr = self._get_map(hwaddr)
+ if addr or not wait:
+ break
+
+ time.sleep(1)
+ wait -= 1
+
+ return addr
+
+ def _get_map(self, hwaddr):
+
+ try:
+ leases_file = open(self._lease_file, "r")
+ except IOError as err:
+ raise VirtUtilsError("Unable to resolve IP mapping (%s)" % err)
+
+ addr = None
+ normalized_hwaddr = normalize_hwaddr(hwaddr)
+ for entry in leases_file:
+ match = re.match(r"\d+\s+([0-9a-f:]+)\s+([0-9\.]+)", entry)
+ if match:
+ entry_hwaddr = normalize_hwaddr(match.group(1))
+ entry_addr = match.group(2)
+ if entry_hwaddr == normalized_hwaddr:
+ addr = entry_addr
+ break
+
+ leases_file.close()
+ return addr
+
+
+ def init(self):
+ tmp_file = NamedTemporaryFile(delete=False)
+ doc = self._get_net_xml_dom()
+
+ doc.writexml(tmp_file)
+ tmp_file.close()
+
+ _virsh("net-create %s" % tmp_file.name)
+ os.unlink(tmp_file.name)
+
+ def cleanup(self):
+ _virsh("net-destroy %s" % self._name)
+ exec_cmd("rm -f %s" % self._lease_file)
+
+ def _get_net_xml_dom(self):
+ doc = minidom.Document()
+
+ net = doc.createElement("network")
+ doc.appendChild(net)
+
+ name = doc.createElement("name")
+ name_text = doc.createTextNode(self._name)
+ name.appendChild(name_text)
+ net.appendChild(name)
+
+ if self._addr:
+ ip = doc.createElement("ip")
+ ip.setAttribute("address", self._addr)
+ ip.setAttribute("netmask", self._mask)
+ net.appendChild(ip)
+
+ dhcp = doc.createElement("dhcp")
+ ip.appendChild(dhcp)
+
+ dhcp_range = doc.createElement("range")
+ dhcp_range.setAttribute("start", self._dhcp_from)
+ dhcp_range.setAttribute("end", self._dhcp_to)
+ dhcp.appendChild(dhcp_range)
+
+ for mapping in self._static_mappings:
+ hwaddr, addr = mapping
+ host = doc.createElement("host")
+ host.setAttribute("mac", hwaddr)
+ host.setAttribute("ip", addr)
+ dhcp.appendChild(host)
+
+ return doc
+
+class BridgeCtl(NetCtl):
+ _remove = False
+
+ def __init__(self, name=None):
+ if not name:
+ name = self._generate_name()
+
+ self._check_name(name)
+ self._name = name
+
+ @staticmethod
+ def _check_name(name):
+ if len(name) > 16:
+ msg = "Bridge name '%s' longer than 16 characters" % name
+ raise VirtUtilsError(msg)
+
+ @staticmethod
+ def _generate_name():
+ devs = scan_netdevs()
+
+ index = 0
+ while True:
+ name = "lnstbr%d" % index
+ index += 1
+ unique = True
+ for dev in devs:
+ if name == dev["name"]:
+ unique = False
+ break
+
+ if unique:
+ return name
+
+ def _exists(self):
+ devs = scan_netdevs()
+ for dev in devs:
+ if self._name == dev["name"]:
+ return True
+
+ return False
+
+ def init(self):
+ if not self._exists():
+ _brctl("addbr %s" % self._name)
+ self._remove = True
+
+ _ip("link set %s up" % self._name)
+
+ def cleanup(self):
+ if self._remove:
+ _ip("link set %s down" % self._name)
+ _brctl("delbr %s" % self._name)
--
1.7.7.6