#
# Copyright 2014 Red Hat, Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
#
# Refer to the README and COPYING files for full details of the license
#
from __future__ import absolute_import
"""
VM Plugins
============
There are two VM-related plugin extension points, there's the
VM Type Plugin, that allows you to modify at a higher level the inner
workings of the VM class (domain concept in the initfile).
The other plugin extension point, the [VM Provider Plugin], that allows you to
create an alternative implementation of the provisioning details for the VM,
for example, using a remote libvirt instance or similar.
"""
from copy import deepcopy
import contextlib
import errno
import functools
from future.builtins import super
import logging
import os
import shutil
import tempfile
import warnings
from abc import (ABCMeta, abstractmethod)
import six
from six import with_metaclass
from scp import SCPClient, SCPException
from .. import (
utils,
log_utils,
plugins,
ssh,
)
from lago.config import config
LOGGER = logging.getLogger(__name__)
LogTask = functools.partial(log_utils.LogTask, logger=LOGGER)
[docs]class VMError(utils.LagoException):
pass
[docs]class LagoVMNotRunningError(utils.LagoUserException):
def __init__(self, vm_name):
super().__init__('VM {} is not running'.format(vm_name))
[docs]class LagoCopyFilesToVMError(utils.LagoUserException):
def __init__(self, local_files, err):
super().__init__(
'Failed to copy files/directory {}\n{}'.format(local_files, err)
)
[docs]class LagoCopyFilesFromVMError(utils.LagoUserException):
def __init__(self, remote_files, local_files, err=''):
super().__init__(
'Failed to copy files/directory from {} to {}\n{}'.format(
remote_files, local_files, err
)
)
[docs]class LagoVMDoesNotExistError(utils.LagoException):
pass
[docs]class LagoFailedToGetVMStateError(utils.LagoException):
pass
[docs]def check_running(func):
@functools.wraps(func)
def wrapper(self, *args, **kwargs):
if not self.running():
raise LagoVMNotRunningError(self.name())
return func(self, *args, **kwargs)
return wrapper
[docs]class VMProviderPlugin(plugins.Plugin):
"""
If you want to use a custom provider for you VMs (say, ovirt for example),
you have to inherit from this class, and then define the
'default_vm_provider' in your config to be your plugin, or explicitly
specify it on each domain definition in the initfile with 'vm-provider' key
You will have to override at least all the abstractmethods in order to
write a provider plugin, even if they are just runnig `pass`.
"""
def __init__(self, vm):
self.vm = vm
[docs] @abstractmethod
def start(self, *args, **kwargs):
"""
Start a domain
Returns:
None
"""
pass
[docs] @abstractmethod
def stop(self, *args, **kwargs):
"""
Stop a domain
Returns:
None
"""
pass
[docs] @abstractmethod
def shutdown(self, *args, **kwargs):
"""
Shutdown a domain
Returns:
None
"""
pass
[docs] @abstractmethod
def reboot(self, *args, **kwargs):
"""
Reboot a domain
Returns:
None
"""
pass
[docs] @abstractmethod
def bootstrap(self, *args, **kwargs):
"""
Does any actions needed to get the domain ready to be used, ran on
prefix init.
Return:
None
"""
pass
[docs] @abstractmethod
def state(self, *args, **kwargs):
"""
Return the current state of the domain
Returns:
str: Small description of the current domain state
"""
pass
[docs] @abstractmethod
def running(self, *args, **kwargs):
"""
Returns:
(bool): True if the VM is running
"""
pass
[docs] @abstractmethod
def create_snapshot(self, name, *args, **kwargs):
"""
Take any actions needed to create a snapshot
Args:
name(str): Name for the snapshot, will be used as key to retrieve
it later
Returns:
None
"""
pass
[docs] @abstractmethod
def revert_snapshot(self, name, *args, **kwargs):
"""
Take any actions needed to revert/restore a snapshot
Args:
name(str): Name for the snapshot, same that was set on creation
Returns:
None
"""
pass
[docs] def export_disks(self, standalone, dst_dir, compress, *args, **kwargs):
"""
Export 'disks' as a standalone image or a layered image.
Args:
disks(list): The names of the disks to export
(None means all the disks)
standalone(bool): If true create a copy of the layered image
else create a new disk which is a combination of the current
layer and the base disk.
dst_dir (str): dir to place the exported images
compress (bool): if true, compress the exported image.
"""
pass
[docs] def interactive_console(self):
"""
Run an interactive console
Returns:
lago.utils.CommandStatus: resulf of the interactive execution
"""
return self.vm.interactive_ssh()
[docs] def name(self):
return self.vm.name()
[docs] @check_running
def _has_tar_and_gzip(self):
with self.vm._ssh() as client:
_, stdout, _ = client.exec_command("ls /usr/bin/tar")
if stdout.read().strip() != "/usr/bin/tar":
return False
_, stdout, _ = client.exec_command("ls /usr/bin/gzip")
if stdout.read().strip() != "/usr/bin/gzip":
return False
return True
[docs] @staticmethod
def _prepare_tar_gz_command(remote_paths, compression_level):
cmd = "tar --dereference -c {} | gzip -f -{}"
remote_paths_arg = " ".join(remote_paths)
return cmd.format(remote_paths_arg, compression_level)
[docs] def _pipe_ssh_cmd_output_to_file(self, cmd, out_file):
with self.vm._ssh() as client:
_, stdout, _ = client.exec_command(cmd)
out_file.write(stdout.read())
out_file.flush()
os.fsync(out_file.fileno())
[docs] @contextlib.contextmanager
def _tar_gz_archive_from(self, remote_paths, compression_level=5):
with tempfile.NamedTemporaryFile() as archive_file:
tar_gz_cmd = self._prepare_tar_gz_command(
remote_paths, compression_level
)
self._pipe_ssh_cmd_output_to_file(tar_gz_cmd, archive_file)
LOGGER.debug(
"Created %s archive with collected paths", archive_file.name
)
yield archive_file
[docs]class VMPlugin(with_metaclass(ABCMeta, plugins.Plugin)):
'''
This class takes care of the high level abstraction for a VM (a domain in
the initfile lingo). From starting/stopping it to loading and calling the
provider if needed. If you want to change only the way the VM is
provisioned you can take a look to the `class:VMProviderPlugin` instead.
This base class includes also some basic methods implemented with ssh.
VM properties:
* name
* cpus
* memory
* disks
* metadata
* network/mac addr
* virt_env
'''
def __init__(self, env, spec):
self.virt_env = env
self._spec = self._normalize_spec(spec.copy())
self._ssh_client = None
self.service_providers = plugins.load_plugins(
namespace=plugins.PLUGIN_ENTRY_POINTS['vm-service'],
instantiate=False,
)
self._service_class = self._get_service_provider()
self.vm_providers = plugins.load_plugins(
namespace=plugins.PLUGIN_ENTRY_POINTS['vm-provider'],
instantiate=False,
)
self.provider = self._get_vm_provider()
[docs] def start(self, *args, **kwargs):
"""
Thin method that just uses the provider
"""
return self.provider.start(*args, **kwargs)
[docs] def stop(self, *args, **kwargs):
"""
Thin method that just uses the provider
"""
return self.provider.stop(*args, **kwargs)
[docs] def shutdown(self, *args, **kwargs):
"""
Thin method that just uses the provider
"""
return self.provider.shutdown(*args, **kwargs)
[docs] def reboot(self, *args, **kwargs):
"""
Thin method that just uses the provider
"""
return self.provider.reboot(*args, **kwargs)
[docs] def bootstrap(self, *args, **kwargs):
"""
Thin method that just uses the provider
"""
return self.provider.bootstrap(*args, **kwargs)
[docs] def state(self, *args, **kwargs):
"""
Thin method that just uses the provider
"""
return self.provider.state(*args, **kwargs)
[docs] def running(self, *args, **kwargs):
"""
Thin method that just uses the provider
"""
return self.provider.running(*args, **kwargs)
[docs] def create_snapshot(self, name, *args, **kwargs):
"""
Thin method that just uses the provider
"""
return self.provider.create_snapshot(name, *args, **kwargs)
[docs] def revert_snapshot(self, name, *args, **kwargs):
"""
Thin method that just uses the provider
"""
return self.provider.revert_snapshot(name, *args, **kwargs)
[docs] def interactive_console(self, *args, **kwargs):
"""
Thin method that just uses the provider
"""
return self.provider.interactive_console(*args, **kwargs)
[docs] def export_disks(
self,
standalone=True,
dst_dir=None,
compress=False,
collect_only=False,
with_threads=True,
*args,
**kwargs
):
"""
Thin method that just uses the provider
"""
return self.provider.export_disks(
standalone, dst_dir, compress, collect_only, with_threads, *args,
**kwargs
)
[docs] def copy_to(self, local_path, remote_path, recursive=True):
with LogTask(
'Copy %s to %s:%s' % (local_path, self.name(), remote_path),
):
try:
with self._scp() as scp:
scp.put(
files=local_path,
remote_path=remote_path,
recursive=recursive,
)
except (OSError, SCPException) as err:
raise LagoCopyFilesToVMError(local_path, str(err))
[docs] def copy_from(
self, remote_path, local_path, recursive=True, propagate_fail=True
):
with LogTask(
'Copy from %s:%s to %s' % (self.name(), remote_path, local_path),
propagate_fail=propagate_fail
):
try:
with self._scp(propagate_fail=propagate_fail) as scp:
scp.get(
recursive=recursive,
remote_path=remote_path,
local_path=local_path,
)
except SCPException as err:
err_substr = ': No such file or directory'
if all(
(
len(err.args) > 0,
isinstance(err.args[0], six.string_types),
err_substr in err.args[0],
)
):
raise ExtractPathNoPathError(err.args[0])
else:
raise LagoCopyFilesFromVMError(
remote_path, local_path, err.args[0]
)
@property
def metadata(self):
return self._spec['metadata'].copy()
@property
def disks(self):
return self._spec['disks'][:]
@property
def spec(self):
return deepcopy(self._spec)
@property
def mgmt_name(self):
return self._spec.get('mgmt_net', None)
@property
def mgmt_net(self):
return self.virt_env.get_net(name=self.mgmt_name)
@property
def vm_type(self):
return self._spec['vm-type']
@property
def groups(self):
"""
Returns:
list of str: The names of the groups to which this vm belongs
(as specified in the init file)
"""
groups = self._spec.get('groups', [])
if groups:
return groups[:]
else:
return groups
@property
def cpu_vendor(self):
return getattr(self.provider, 'cpu_vendor')
@property
def cpu_model(self):
return getattr(self.provider, 'cpu_model')
[docs] def name(self):
return str(self._spec['name'])
[docs] def iscsi_name(self):
return 'iqn.2014-07.org.lago:%s' % self.name()
[docs] def ip(self):
res = self.mgmt_net.resolve(self.name())
return res.encode('ascii', 'ignore')
[docs] def all_ips(self):
nets = {}
ips = []
nets = self.virt_env.get_nets()
for net in nets.values():
mapping = net.mapping()
for hostname, ip in mapping.items():
# hostname is <hostname>-<ifacename>
if hostname.startswith(self.name() + "-"):
ips.append(str(ip))
return ips
[docs] def ips_in_net(self, net_name):
ips = []
net = self.virt_env.get_net(name=net_name)
mapping = net.mapping()
for hostname, ip in mapping.items():
# hostname is <hostname>-<ifacename>
if hostname.startswith(self.name() + "-"):
ips.append(str(ip))
return ips
[docs] def ssh(
self,
command,
data=None,
show_output=True,
propagate_fail=True,
tries=None,
):
if not self.running():
raise RuntimeError('Attempt to ssh into a not running host')
return ssh.ssh(
ip_addr=self.ip(),
host_name=self.name(),
command=command,
data=None,
show_output=True,
propagate_fail=True,
tries=None,
ssh_key=self.virt_env.prefix.paths.ssh_id_rsa(),
username=self._spec.get('ssh-user'),
password=self._spec.get('ssh-password'),
)
[docs] def wait_for_ssh(self):
return ssh.wait_for_ssh(
ip_addr=self.ip(),
host_name=self.name(),
connect_timeout=self._spec.get('boot_time_sec', 600),
ssh_key=self.virt_env.prefix.paths.ssh_id_rsa(),
username=self._spec.get('ssh-user'),
password=self._spec.get('ssh-password'),
)
[docs] def ssh_script(self, path, show_output=True):
return ssh.ssh_script(
ip_addr=self.ip(),
host_name=self.name(),
ssh_key=self.virt_env.prefix.paths.ssh_id_rsa(),
path=path,
show_output=show_output,
username=self._spec.get('ssh-user'),
password=self._spec.get('ssh-password'),
)
[docs] def ssh_reachable(self, tries=None, propagate_fail=True):
"""
Check if the VM is reachable with ssh
Args:
tries(int): Number of tries to try connecting to the host
propagate_fail(bool): If set to true, this event will appear
in the log and fail the outter stage. Otherwise, it will be
discarded.
Returns:
bool: True if the VM is reachable.
"""
if not self.running():
return False
try:
ssh.get_ssh_client(
ip_addr=self.ip(),
host_name=self.name(),
ssh_tries=tries,
propagate_fail=propagate_fail,
ssh_key=self.virt_env.prefix.paths.ssh_id_rsa(),
username=self._spec.get('ssh-user'),
password=self._spec.get('ssh-password'),
)
except ssh.LagoSSHTimeoutException:
return False
return True
[docs] def save(self, path=None):
if path is None:
path = self.virt_env.virt_path('vm-%s' % self.name())
dst_dir = os.path.dirname(path)
if not os.path.exists(dst_dir):
os.makedirs(dst_dir)
with open(path, 'w') as f:
utils.json_dump(self._spec, f)
[docs] @check_running
def service(self, name):
if self._service_class is None:
self._detect_service_provider()
return self._service_class(self, name)
[docs] @check_running
def interactive_ssh(self, command=None):
if command is None:
command = ['bash']
return ssh.interactive_ssh(
ip_addr=self.ip(),
host_name=self.name(),
ssh_key=self.virt_env.prefix.paths.ssh_id_rsa(),
command=command,
username=self._spec.get('ssh-user'),
password=self._spec.get('ssh-password'),
)
[docs] def nics(self):
return self._spec['nics'][:]
[docs] def nets(self):
return [nic['net'] for nic in self._spec['nics']]
[docs] def distro(self):
distro = self._spec.get('distro', None)
if distro is None:
distro = self._template_metadata().get('distro', None)
return distro
[docs] def root_password(self):
root_password = self._spec.get('root-password', None)
if root_password is None:
root_password = self._spec.get('ssh-password', '')
return root_password
[docs] def collect_artifacts(self, host_path, ignore_nopath):
self.extract_paths(
[
(
guest_path,
os.path.join(host_path, guest_path.replace('/', '_')),
) for guest_path in self._artifact_paths()
],
ignore_nopath=ignore_nopath
)
[docs] def guest_agent(self):
if 'guest-agent' not in self._spec:
for possible_name in ('qemu-guest-agent', 'qemu-ga'):
try:
if self.service(possible_name).exists():
self._spec['guest-agent'] = possible_name
self.save()
break
except RuntimeError as err:
raise RuntimeError(
'Could not find guest agent service: %s' % err
)
else:
raise RuntimeError('Could not find guest agent service')
return self.service(self._spec['guest-agent'])
[docs] def has_guest_agent(self):
try:
self.guest_agent()
except RuntimeError:
return False
return True
[docs] def _get_vm_provider(self):
default_provider = config.get('default_vm_provider')
provider_name = self._spec.get('vm-provider', default_provider)
provider = self.vm_providers.get(provider_name)
self._spec['vm-provider'] = provider_name
return provider(vm=self)
[docs] @classmethod
def _normalize_spec(cls, spec):
spec['snapshots'] = spec.get('snapshots', {})
spec['metadata'] = spec.get('metadata', {})
if 'root-password' not in spec:
root_password = config.get('root_password')
if root_password:
spec['ssh-password'] = root_password
else:
spec['ssh-password'] = config.get('ssh_password')
if 'ssh-user' not in spec:
spec['ssh-user'] = config.get('ssh_user')
return spec
[docs] @contextlib.contextmanager
def _ssh(self, propagate_fail=True):
client = ssh.get_ssh_client(
propagate_fail=propagate_fail,
ip_addr=self.ip(),
host_name=self.name(),
ssh_key=self.virt_env.prefix.paths.ssh_id_rsa(),
username=self._spec.get('ssh-user'),
password=self._spec.get('ssh-password'),
)
try:
yield client
finally:
client.close()
[docs] @contextlib.contextmanager
def _scp(self, propagate_fail=True):
with self._ssh(propagate_fail) as ssh_client:
scp = SCPClient(ssh_client.get_transport())
yield scp
[docs] def _detect_service_provider(self):
LOGGER.debug('Detecting service provider for %s', self.name())
for provider_name, service_class in self.service_providers.items():
if service_class.is_supported(self):
LOGGER.debug(
'Setting %s as service provider for %s',
provider_name,
self.name(),
)
self._service_class = service_class
self._spec['service_provider'] = provider_name
self.save()
return
raise RuntimeError('No service provider detected for %s' % self.name())
[docs] def _artifact_paths(self):
return self._spec.get('artifacts', [])
[docs] def _get_service_provider(self):
"""
**NOTE**: Can be reduced to just one get call once we remove support
for the service_class spec entry
Returns:
class: class for the loaded provider for that vm_spec
None: if no provider was specified in the vm_spec
"""
service_class = self._spec.get('service_class', None)
if service_class is not None:
warnings.warn(
'The service_class key for a domain is deprecated, you should '
'change it to service_provider instead'
)
service_provider = _resolve_service_class(
class_name=service_class,
service_providers=self.service_providers,
)
else:
service_provider = self.service_providers.get(
self._spec.get('service_provider', None),
None,
)
return service_provider
[docs]def _resolve_service_class(class_name, service_providers):
"""
**NOTE**: This must be remved once the service_class spec entry is fully
deprecated
Retrieves a service plugin class from the class name instead of the
provider name
Args:
class_name(str): Class name of the service plugin to retrieve
service_providers(dict): provider_name->provider_class of the loaded
service providers
Returns:
class: Class of the plugin that matches that name
Raises:
lago.plugins.NoSuchPluginError: if there was no service plugin that
matched the search
"""
for plugin in service_providers.itervalues():
if plugin.__class__.__name__ == class_name:
return plugin
raise plugins.NoSuchPluginError(
'No service provider plugin with class name %s found, loaded '
'providers: %s' % (
class_name,
[
plugin.__class__.__name__
for plugin in service_providers.itervalues()
],
)
)
