X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/505be2eb9ac1f36a5e31b374451193bc1ab7e90e..0561bd0c3c07257fd58ded6c7cfa5feeae97af57:/services/nodemanager/arvnodeman/computenode/driver/__init__.py diff --git a/services/nodemanager/arvnodeman/computenode/driver/__init__.py b/services/nodemanager/arvnodeman/computenode/driver/__init__.py index 724c772733..8f881b04e3 100644 --- a/services/nodemanager/arvnodeman/computenode/driver/__init__.py +++ b/services/nodemanager/arvnodeman/computenode/driver/__init__.py @@ -1,15 +1,20 @@ #!/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 NETWORK_ERRORS +from ...config import CLOUD_ERRORS +from .. import RetryMixin -class BaseComputeNodeDriver(object): +class BaseComputeNodeDriver(RetryMixin): """Abstract base class for compute node drivers. libcloud drivers abstract away many of the differences between @@ -22,9 +27,18 @@ class BaseComputeNodeDriver(object): Subclasses must implement arvados_create_kwargs, sync_node, node_fqdn, and node_start_time. """ - CLOUD_ERRORS = NETWORK_ERRORS + (cloud_types.LibcloudError,) - def __init__(self, auth_kwargs, list_kwargs, create_kwargs, driver_class): + + @RetryMixin._retry() + def _create_driver(self, driver_class, **auth_kwargs): + return driver_class(**auth_kwargs) + + @RetryMixin._retry() + def _set_sizes(self): + self.sizes = {sz.id: sz for sz in self.real.list_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: @@ -37,7 +51,12 @@ class BaseComputeNodeDriver(object): libcloud driver's create_node method to create a new compute node. * driver_class: The class of a libcloud driver to use. """ - self.real = driver_class(**auth_kwargs) + + 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 @@ -53,6 +72,8 @@ class BaseComputeNodeDriver(object): if new_pair is not None: self.create_kwargs[new_pair[0]] = new_pair[1] + self._set_sizes() + def _init_ping_host(self, ping_host): self.ping_host = ping_host @@ -61,35 +82,62 @@ class BaseComputeNodeDriver(object): key = NodeAuthSSHKey(ssh_file.read()) return 'auth', key - def search_for(self, term, list_method, key=attrgetter('id'), **kwargs): + 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 on this - instance's libcloud driver for a list of objects. + * 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: - items = getattr(self.real, list_method)(**kwargs) - results = [item for item in items - if key(item) == term] - count = len(results) - if count != 1: - raise ValueError("{} returned {} results for '{}'".format( - list_method, count, term)) - self.SEARCH_CACHE[cache_key] = results[0] + self.SEARCH_CACHE[cache_key] = self.search_for_now( + term, list_method, key, **kwargs) return self.SEARCH_CACHE[cache_key] - def list_nodes(self): - return self.real.list_nodes(**self.list_kwargs) + def list_nodes(self, **kwargs): + l = self.list_kwargs.copy() + l.update(kwargs) + return self.real.list_nodes(**l) - def arvados_create_kwargs(self, arvados_node): + 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 @@ -98,21 +146,42 @@ class BaseComputeNodeDriver(object): 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): - kwargs = self.create_kwargs.copy() - kwargs.update(self.arvados_create_kwargs(arvados_node)) - kwargs['size'] = size - return self.real.create_node(**kwargs) + try: + kwargs = self.create_kwargs.copy() + kwargs.update(self.arvados_create_kwargs(size, arvados_node)) + kwargs['size'] = size + 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: + raise create_error def post_create_node(self, cloud_node): # ComputeNodeSetupActor calls this method after the cloud node is @@ -139,13 +208,22 @@ class BaseComputeNodeDriver(object): # seconds since the epoch UTC. raise NotImplementedError("BaseComputeNodeDriver.node_start_time") - @classmethod - def is_cloud_exception(cls, exception): - # libcloud compute drivers typically raise bare Exceptions to - # represent API errors. Return True for any exception that is - # exactly an Exception, or a better-known higher-level exception. - return (isinstance(exception, cls.CLOUD_ERRORS) or - type(exception) is Exception) + def destroy_node(self, cloud_node): + try: + return self.real.destroy_node(cloud_node) + except CLOUD_ERRORS as destroy_error: + # 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. + raise # Now that we've defined all our own methods, delegate generic, public # attributes of libcloud drivers that we haven't defined ourselves. @@ -155,6 +233,11 @@ class BaseComputeNodeDriver(object): 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):