#
# Copyright (C) 2013, 2015, 2019 University of Zurich.
#
# 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 3 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, see <http://www.gnu.org/licenses/>.
#
__author__ = 'Nicolas Baer <nicolas.baer@uzh.ch>'
# compatibility imports
from future.utils import with_metaclass
# stdlib imports
from builtins import object
from abc import ABCMeta, abstractmethod
[docs]class AbstractCloudProvider(with_metaclass(ABCMeta, object)):
"""Defines the contract for a cloud provider to proper function with
elasticluster.
"""
@abstractmethod
def __init__(self, **config):
"""The constructor of a `CloudProvider` class is called only
using keyword arguments.
Usually these are configuration option of the corresponding
`setup` section in the configuration file.
"""
pass
[docs] @abstractmethod
def to_vars_dict(self):
"""
Return local state which is relevant for the cluster setup process.
"""
return {}
[docs] @abstractmethod
def start_instance(self, key_name, public_key_path, private_key_path,
security_group, flavor, image_id, image_userdata,
username=None, node_name=None):
"""Starts a new instance on the cloud using the given properties.
Multiple instances might be started in different threads at the same
time. The implementation should handle any problems regarding this
itself.
:param str key_name: name of the ssh key to connect
:param str public_key_path: path to ssh public key
:param str private_key_path: path to ssh private key
:param str security_group: firewall rule definition to apply on the
instance
:param str flavor: machine type to use for the instance
:param str image_name: image type (os) to use for the instance
:param str image_userdata: command to execute after startup
:param str username: username for the given ssh key, default None
:return: Dictionary of instance attributes to record.
"""
pass
[docs] @abstractmethod
def pause_instance(self, instance_id):
"""Pauses the instance - retaining disks and configuration.
:param str instance_id: instance identifier
:return: dict - Dictionary of configuration required to restart instance.
"""
pass
[docs] @abstractmethod
def resume_instance(self, instance_config):
"""Restart an instance from a dictionary of configuration.
:param dict instance_config:
Dictionary of configuration returned from `pause_instance`:meth:
:return: str - instance_id
"""
pass
[docs] @abstractmethod
def stop_instance(self, instance_id):
"""Stops the instance gracefully.
:param str instance_id: instance identifier
:return: None
"""
pass
[docs] @abstractmethod
def get_ips(self, instance_id):
"""Retrieves the private and public ip addresses for a given instance.
:return: list (IPs)
"""
pass
[docs] @abstractmethod
def is_instance_running(self, instance_id):
"""Checks if the instance is up and running.
:param str instance_id: instance identifier
:return: bool - True if running, False otherwise
"""
pass
[docs]class AbstractSetupProvider(with_metaclass(ABCMeta, object)):
"""
TODO: define...
"""
#: to identify this provider type in messages; override in subclasses
HUMAN_READABLE_NAME = 'setup provider'
[docs] @abstractmethod
def setup_cluster(self, cluster, extra_args=tuple()):
"""
Configure all nodes of a cluster.
This method *must* be idempotent, i.e. it should always be
safe to call multiple times over.
:param cluster: cluster to configure
:type cluster: :py:class:`elasticluster.cluster.Cluster`
:param list extra_args:
List of additional command-line arguments
that are appended to each invocation of the setup program.
:return: `True` if the cluster is correctly configured, even
if the method didn't actually do anything. `False` if the
cluster is not configured.
"""
pass
[docs] @abstractmethod
def cleanup(self):
"""Cleanup any temporary file or directory created during setup.
This method is called every time a cluster is stopped.
:return: None
"""
pass