+++ /dev/null
-#!/usr/bin/env python
-# Copyright (C) The Arvados Authors. All rights reserved.
-#
-# SPDX-License-Identifier: AGPL-3.0
-
-from __future__ import absolute_import, print_function
-
-import logging
-from operator import attrgetter
-
-import libcloud.common.types as cloud_types
-from libcloud.compute.base import NodeDriver, NodeAuthSSHKey
-
-from ...config import CLOUD_ERRORS
-from ...status import tracker
-from .. import RetryMixin
-
-class BaseComputeNodeDriver(RetryMixin):
- """Abstract base class for compute node drivers.
-
- libcloud drivers abstract away many of the differences between
- cloud providers, but managing compute nodes requires some
- cloud-specific features (e.g., keeping track of node FQDNs and
- boot times). Compute node drivers are responsible for translating
- the node manager's cloud requests to a specific cloud's
- vocabulary.
-
- Subclasses must implement arvados_create_kwargs, sync_node,
- node_fqdn, and node_start_time.
- """
-
-
- @RetryMixin._retry()
- def _create_driver(self, driver_class, **auth_kwargs):
- return driver_class(**auth_kwargs)
-
- @RetryMixin._retry()
- def sizes(self):
- if self._sizes is None:
- self._sizes = {sz.id: sz for sz in self.real.list_sizes()}
- return self._sizes
-
- def __init__(self, auth_kwargs, list_kwargs, create_kwargs,
- driver_class, retry_wait=1, max_retry_wait=180):
- """Base initializer for compute node drivers.
-
- Arguments:
- * auth_kwargs: A dictionary of arguments that are passed into the
- driver_class constructor to instantiate a libcloud driver.
- * list_kwargs: A dictionary of arguments that are passed to the
- libcloud driver's list_nodes method to return the list of compute
- nodes.
- * create_kwargs: A dictionary of arguments that are passed to the
- libcloud driver's create_node method to create a new compute node.
- * driver_class: The class of a libcloud driver to use.
- """
-
- super(BaseComputeNodeDriver, self).__init__(retry_wait, max_retry_wait,
- logging.getLogger(self.__class__.__name__),
- type(self),
- None)
- self.real = self._create_driver(driver_class, **auth_kwargs)
- self.list_kwargs = list_kwargs
- self.create_kwargs = create_kwargs
- # Transform entries in create_kwargs. For each key K, if this class
- # has an _init_K method, remove the entry and call _init_K with the
- # corresponding value. If _init_K returns None, the entry stays out
- # of the dictionary (we expect we're holding the value somewhere
- # else, like an instance variable). Otherwise, _init_K returns a
- # key-value tuple pair, and we add that entry to create_kwargs.
- for key in self.create_kwargs.keys():
- init_method = getattr(self, '_init_' + key, None)
- if init_method is not None:
- new_pair = init_method(self.create_kwargs.pop(key))
- if new_pair is not None:
- self.create_kwargs[new_pair[0]] = new_pair[1]
-
- self._sizes = None
-
- def _init_ping_host(self, ping_host):
- self.ping_host = ping_host
-
- def _init_ssh_key(self, filename):
- with open(filename) as ssh_file:
- key = NodeAuthSSHKey(ssh_file.read())
- return 'auth', key
-
- def search_for_now(self, term, list_method, key=attrgetter('id'), **kwargs):
- """Return one matching item from a list of cloud objects.
-
- Raises ValueError if the number of matching objects is not exactly 1.
-
- Arguments:
- * term: The value that identifies a matching item.
- * list_method: A string that names the method to call for a
- list of objects.
- * key: A function that accepts a cloud object and returns a
- value search for a `term` match on each item. Returns the
- object's 'id' attribute by default.
- """
- try:
- list_func = getattr(self, list_method)
- except AttributeError:
- list_func = getattr(self.real, list_method)
- items = list_func(**kwargs)
- results = [item for item in items if key(item) == term]
- count = len(results)
- if count != 1:
- raise ValueError("{} returned {} results for {!r}".format(
- list_method, count, term))
- return results[0]
-
- def search_for(self, term, list_method, key=attrgetter('id'), **kwargs):
- """Return one cached matching item from a list of cloud objects.
-
- See search_for_now() for details of arguments and exceptions.
- This method caches results, so it's good to find static cloud objects
- like node sizes, regions, etc.
- """
- cache_key = (list_method, term)
- if cache_key not in self.SEARCH_CACHE:
- self.SEARCH_CACHE[cache_key] = self.search_for_now(
- term, list_method, key, **kwargs)
- return self.SEARCH_CACHE[cache_key]
-
- def list_nodes(self, **kwargs):
- l = self.list_kwargs.copy()
- l.update(kwargs)
- try:
- return self.real.list_nodes(**l)
- except CLOUD_ERRORS:
- tracker.counter_add('list_nodes_errors')
- raise
-
- def create_cloud_name(self, arvados_node):
- """Return a cloud node name for the given Arvados node record.
-
- Subclasses must override this method. It should return a string
- that can be used as the name for a newly-created cloud node,
- based on identifying information in the Arvados node record.
-
- Arguments:
- * arvados_node: This Arvados node record to seed the new cloud node.
- """
- raise NotImplementedError("BaseComputeNodeDriver.create_cloud_name")
-
- def arvados_create_kwargs(self, size, arvados_node):
- """Return dynamic keyword arguments for create_node.
-
- Subclasses must override this method. It should return a dictionary
- of keyword arguments to pass to the libcloud driver's create_node
- method. These arguments will extend the static arguments in
- create_kwargs.
-
- Arguments:
- * size: The node size that will be created (libcloud NodeSize object)
- * arvados_node: The Arvados node record that will be associated
- with this cloud node, as returned from the API server.
- """
- raise NotImplementedError("BaseComputeNodeDriver.arvados_create_kwargs")
-
- def broken(self, cloud_node):
- """Return true if libcloud has indicated the node is in a "broken" state."""
- return False
-
- def _make_ping_url(self, arvados_node):
- return 'https://{}/arvados/v1/nodes/{}/ping?ping_secret={}'.format(
- self.ping_host, arvados_node['uuid'],
- arvados_node['info']['ping_secret'])
-
- @staticmethod
- def _name_key(cloud_object):
- return cloud_object.name
-
- def create_node(self, size, arvados_node):
- try:
- kwargs = self.create_kwargs.copy()
- kwargs.update(self.arvados_create_kwargs(size, arvados_node))
- kwargs['size'] = size.real
- return self.real.create_node(**kwargs)
- except CLOUD_ERRORS as create_error:
- # Workaround for bug #6702: sometimes the create node request
- # succeeds but times out and raises an exception instead of
- # returning a result. If this happens, we get stuck in a retry
- # loop forever because subsequent create_node attempts will fail
- # due to node name collision. So check if the node we intended to
- # create shows up in the cloud node list and return it if found.
- try:
- return self.search_for_now(kwargs['name'], 'list_nodes', self._name_key)
- except ValueError:
- tracker.counter_add('create_node_errors')
- raise create_error
-
- def post_create_node(self, cloud_node):
- # ComputeNodeSetupActor calls this method after the cloud node is
- # created. Any setup tasks that need to happen afterward (e.g.,
- # tagging) should be done in this method.
- pass
-
- def sync_node(self, cloud_node, arvados_node):
- # When a compute node first pings the API server, the API server
- # will automatically assign some attributes on the corresponding
- # node record, like hostname. This method should propagate that
- # information back to the cloud node appropriately.
- raise NotImplementedError("BaseComputeNodeDriver.sync_node")
-
- @classmethod
- def node_fqdn(cls, node):
- # This method should return the FQDN of the node object argument.
- # Different clouds store this in different places.
- raise NotImplementedError("BaseComputeNodeDriver.node_fqdn")
-
- @classmethod
- def node_start_time(cls, node):
- # This method should return the time the node was started, in
- # seconds since the epoch UTC.
- raise NotImplementedError("BaseComputeNodeDriver.node_start_time")
-
- def destroy_node(self, cloud_node):
- try:
- return self.real.destroy_node(cloud_node)
- except CLOUD_ERRORS:
- # Sometimes the destroy node request succeeds but times out and
- # raises an exception instead of returning success. If this
- # happens, we get a noisy stack trace. Check if the node is still
- # on the node list. If it is gone, we can declare victory.
- try:
- self.search_for_now(cloud_node.id, 'list_nodes')
- except ValueError:
- # If we catch ValueError, that means search_for_now didn't find
- # it, which means destroy_node actually succeeded.
- return True
- # The node is still on the list. Re-raise.
- tracker.counter_add('destroy_node_errors')
- raise
-
- # Now that we've defined all our own methods, delegate generic, public
- # attributes of libcloud drivers that we haven't defined ourselves.
- def _delegate_to_real(attr_name):
- return property(
- lambda self: getattr(self.real, attr_name),
- lambda self, value: setattr(self.real, attr_name, value),
- doc=getattr(getattr(NodeDriver, attr_name), '__doc__', None))
-
- # node id
- @classmethod
- def node_id(cls):
- raise NotImplementedError("BaseComputeNodeDriver.node_id")
-
- _locals = locals()
- for _attr_name in dir(NodeDriver):
- if (not _attr_name.startswith('_')) and (_attr_name not in _locals):
- _locals[_attr_name] = _delegate_to_real(_attr_name)
projects / arvados.git / blobdiff