Re: [Kimchi-devel] [PATCH v3 3/4] CDROM Management: Devices management model implementation

From: Rodrigo Trujillo <rodrigo.trujillo(a)linux.vnet.ibm.com&gt; This patch adds the CREATE, LOOKUP, UPDATE and DELETE functionalities to guest storage devices support. Signed-off-by: Rodrigo Trujillo <rodrigo.trujillo(a)linux.vnet.ibm.com&gt; Using lxml and objectify to parse the XML info. Pep8 adjustments in model/vms.py Signed-off-by: Daniel Henrique Barboza <danielhb(a)linux.vnet.ibm.com&gt; --- src/kimchi/model/vms.py | 184 ++++++++++++++++++++++++++++++++++++++++++++++-- src/kimchi/xmlutils.py | 5 ++ 2 files changed, 185 insertions(+), 4 deletions(-) diff --git a/src/kimchi/model/vms.py b/src/kimchi/model/vms.py index 1244eeb..3c2a661 100644 --- a/src/kimchi/model/vms.py +++ b/src/kimchi/model/vms.py @@ -20,13 +20,17 @@ # License along with this library; if not, write to the Free Software # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA +import libvirt import os +import socket +import string import time +import urlparse import uuid -from xml.etree import ElementTree -import libvirt from cherrypy.process.plugins import BackgroundTask +from lxml import etree, objectify +from xml.etree import ElementTree from kimchi import vnc from kimchi import xmlutils @@ -36,7 +40,8 @@ from kimchi.model.config import CapabilitiesModel from kimchi.model.templates import TemplateModel from kimchi.model.utils import get_vm_name from kimchi.screenshot import VMScreenshot -from kimchi.utils import run_setfacl_set_attr, template_name_from_uri +from kimchi.utils import kimchi_log, run_setfacl_set_attr +from kimchi.utils import template_name_from_uri DOM_STATE_MAP = {0: 'nostate', @@ -47,6 +52,10 @@ DOM_STATE_MAP = {0: 'nostate', 5: 'shutoff', 6: 'crashed'} +DEV_TYPE_SRC_ATTR_MAP = {'file': 'file', + 'block': 'dev', + 'dir': 'dir'} + GUESTS_STATS_INTERVAL = 5 VM_STATIC_UPDATE_PARAMS = {'name': './name'} VM_LIVE_UPDATE_PARAMS = {} @@ -222,7 +231,7 @@ class VMModel(object): dom = self.get_vm(name, self.conn) dom = self._static_vm_update(dom, params) self._live_vm_update(dom, params) - return dom.name().decode('utf-8') + return dom.name() def _static_vm_update(self, dom, params): state = DOM_STATE_MAP[dom.info()[0]] @@ -453,3 +462,170 @@ class LibvirtVMScreenshot(VMScreenshot): stream.finish() finally: os.close(fd) + + +class StoragesModel(object): + def __init__(self, **kargs): + self.conn = kargs['conn'] + + def _get_storage_xml(self, params): + storage = """ + <disk type='%(src_type)s' device='%(dev_type)s'> + <driver name='qemu' type='raw'/>%(source)s + <target dev='%(dev)s' bus='ide'/> + </disk> + """

+ info = {} + info['dev'] = params.get('dev') + info['dev_type'] = params.get('type') + info['src_type'] = params.get('src_type') + + # Working with url paths + if info['src_type'] == 'network': + net = {} + output = urlparse.urlparse(params.get('path')) + net['protocol'] = output.scheme + net['port'] = output.port or socket.getservbyname(output.scheme) + net['hostname'] = output.hostname + net['url_path'] = output.path + info['source'] = """ + <source protocol='%(protocol)s' name='%(url_path)s'> + <host name='%(hostname)s' port='%(port)s'/> + </source>""" % net

+ else: + # Fixing source attribute + info['source'] = """ + <source %s='%s'/>""" % (DEV_TYPE_SRC_ATTR_MAP[info['src_type']], + params.get('path')) + return storage % info + + def create(self, vm_name, params): + #TODO: Check if device name is already use + path = params.get('path') + + # Checking if path exist, if not url + if path.startswith('/'): + if not os.path.exists(path): + msg = "Path specified for device is not valid" + raise InvalidParameter(msg) + elif path.endswith('.iso') or os.path.isfile(path): + params['src_type'] = 'file' + elif os.path.isdir(path): + params['src_type'] = 'dir'

+ else: + params['src_type'] = 'block'

+ else: + params['src_type'] = 'network'

+ + # Use device name passed or pick next + dev_name = params.get('dev') + if not dev_name: + params['dev'] = self._get_storage_device_name(vm_name) + + # Add device to VM + dev_xml = self._get_storage_xml(params) + try: + conn = self.conn.get() + dom = conn.lookupByName(vm_name) + dom.attachDeviceFlags(dev_xml, libvirt.VIR_DOMAIN_AFFECT_CURRENT) + except Exception as e: + msg = 'Was not possible to attach storage device: %s' % e.message + kimchi_log.error(msg) + raise OperationFailed(e.message) + return params['dev'] + + def _get_storage_device_name(self, vm_name): + dev_list = [dev for dev in self.get_list(vm_name) + if dev.startswith('hd')] + if len(dev_list) == 0: + return 'hda' + dev_list.sort() + last_dev = dev_list.pop() + # TODO: Improve to device names "greater then" hdz + next_dev_letter_pos = string.ascii_lowercase.index(last_dev[2]) + 1 + return 'hd' + string.ascii_lowercase[next_dev_letter_pos] + + def get_list(self, vm_name): + dom = VMModel.get_vm(vm_name, self.conn) + xml = dom.XMLDesc(0) + devices = objectify.fromstring(xml).devices + storages = [disk.target.attrib['dev'] + for disk in devices.xpath("./disk[@device='disk']")] + storages += [disk.target.attrib['dev'] + for disk in devices.xpath("./disk[@device='cdrom']")] + return storages + + +class StorageModel(object): + def __init__(self, **kargs): + self.conn = kargs['conn'] + self.kargs = kargs + + def _get_device_xml(self, vm_name, dev_name): + # Get VM xml and then devices xml + dom = VMModel.get_vm(vm_name, self.conn) + xml = dom.XMLDesc(0) + devices = objectify.fromstring(xml).devices + disk = devices.xpath("./disk/target[@dev='%s']/.." % dev_name) + return disk[0] + + def lookup(self, vm_name, dev_name): + # Retrieve disk xml and format return dict + disk = self._get_device_xml(vm_name, dev_name) + if disk is None: + raise NotFoundError('The storage device "%s" does not exist in ' + 'the guest "%s"' % (dev_name, vm_name)) + source = disk.source + path = "" + if source is not None: + src_type = disk.attrib['type'] + if src_type == 'network': + host = source.host + path = (source.attrib['protocol'] + '://' + + host.attrib['name'] + ':' + + host.attrib['port'] + source.attrib['name']) + else: + path = source.attrib[DEV_TYPE_SRC_ATTR_MAP[src_type]] + dev_type = disk.attrib['device'] + return {'dev': dev_name, + 'type': dev_type, + 'path': path} + + def delete(self, vm_name, dev_name): + # Get storage device xml + disk = self._get_device_xml(vm_name, dev_name) + if disk is None: + raise NotFoundError('The storage device "%s" does not exist in ' + 'the guest "%s"' % (dev_name, vm_name)) + try: + conn = self.conn.get() + dom = conn.lookupByName(vm_name) + dom.detachDeviceFlags(etree.tostring(disk), + libvirt.VIR_DOMAIN_AFFECT_CURRENT) + except Exception as e: + msg = 'Was not possible to detach storage device: %s' % e.message + kimchi_log.error(msg) + raise OperationFailed(e.message) + + def update(self, vm_name, dev_name, params): + info = self.lookup(vm_name, dev_name) + backup_params = info.copy() + try: + self.delete(vm_name, dev_name) + except: + msg = 'Was not possible to update storage device: %s' % e.message + kimchi_log.error(msg) + raise OperationFailed(e.message) + + info.update(params) + kargs = {'conn': self.conn} + stgModel = StoragesModel(**kargs) + try: + dev_name = stgModel.create(vm_name, info) + return dev_name + except Exception as e: + # Restoring previous device + dev_name = stgModel.create(vm_name, backup_params) + msg = 'Was not possible to update storage device: %s' % e.message + kimchi_log.error(msg) + raise OperationFailed(e.message) diff --git a/src/kimchi/xmlutils.py b/src/kimchi/xmlutils.py index 51ff0ec..176ceb1 100644 --- a/src/kimchi/xmlutils.py +++ b/src/kimchi/xmlutils.py @@ -40,3 +40,8 @@ def xml_item_update(xml, xpath, value): item = root.find(xpath) item.text = value return ElementTree.tostring(root, encoding="utf-8") + +def xml_get_child(xml, xpath): + root = ElementTree.fromstring(xml) + item = root.find(xpath) + return ElementTree.tostring(item, encoding="utf-8")