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Diffstat (limited to 'charms/trusty/ceilometer-agent/hooks/charmhelpers/contrib/hahelpers/cluster.py')
| -rw-r--r-- | charms/trusty/ceilometer-agent/hooks/charmhelpers/contrib/hahelpers/cluster.py | 363 |
1 files changed, 0 insertions, 363 deletions
diff --git a/charms/trusty/ceilometer-agent/hooks/charmhelpers/contrib/hahelpers/cluster.py b/charms/trusty/ceilometer-agent/hooks/charmhelpers/contrib/hahelpers/cluster.py deleted file mode 100644 index e02350e..0000000 --- a/charms/trusty/ceilometer-agent/hooks/charmhelpers/contrib/hahelpers/cluster.py +++ /dev/null @@ -1,363 +0,0 @@ -# Copyright 2014-2015 Canonical Limited. -# -# Licensed under the Apache License, Version 2.0 (the "License"); -# you may not use this file except in compliance with the License. -# You may obtain a copy of the License at -# -# http://www.apache.org/licenses/LICENSE-2.0 -# -# Unless required by applicable law or agreed to in writing, software -# distributed under the License is distributed on an "AS IS" BASIS, -# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -# See the License for the specific language governing permissions and -# limitations under the License. - -# -# Copyright 2012 Canonical Ltd. -# -# Authors: -# James Page <james.page@ubuntu.com> -# Adam Gandelman <adamg@ubuntu.com> -# - -""" -Helpers for clustering and determining "cluster leadership" and other -clustering-related helpers. -""" - -import subprocess -import os - -from socket import gethostname as get_unit_hostname - -import six - -from charmhelpers.core.hookenv import ( - log, - relation_ids, - related_units as relation_list, - relation_get, - config as config_get, - INFO, - DEBUG, - WARNING, - unit_get, - is_leader as juju_is_leader, - status_set, -) -from charmhelpers.core.decorators import ( - retry_on_exception, -) -from charmhelpers.core.strutils import ( - bool_from_string, -) - -DC_RESOURCE_NAME = 'DC' - - -class HAIncompleteConfig(Exception): - pass - - -class HAIncorrectConfig(Exception): - pass - - -class CRMResourceNotFound(Exception): - pass - - -class CRMDCNotFound(Exception): - pass - - -def is_elected_leader(resource): - """ - Returns True if the charm executing this is the elected cluster leader. - - It relies on two mechanisms to determine leadership: - 1. If juju is sufficiently new and leadership election is supported, - the is_leader command will be used. - 2. If the charm is part of a corosync cluster, call corosync to - determine leadership. - 3. If the charm is not part of a corosync cluster, the leader is - determined as being "the alive unit with the lowest unit numer". In - other words, the oldest surviving unit. - """ - try: - return juju_is_leader() - except NotImplementedError: - log('Juju leadership election feature not enabled' - ', using fallback support', - level=WARNING) - - if is_clustered(): - if not is_crm_leader(resource): - log('Deferring action to CRM leader.', level=INFO) - return False - else: - peers = peer_units() - if peers and not oldest_peer(peers): - log('Deferring action to oldest service unit.', level=INFO) - return False - return True - - -def is_clustered(): - for r_id in (relation_ids('ha') or []): - for unit in (relation_list(r_id) or []): - clustered = relation_get('clustered', - rid=r_id, - unit=unit) - if clustered: - return True - return False - - -def is_crm_dc(): - """ - Determine leadership by querying the pacemaker Designated Controller - """ - cmd = ['crm', 'status'] - try: - status = subprocess.check_output(cmd, stderr=subprocess.STDOUT) - if not isinstance(status, six.text_type): - status = six.text_type(status, "utf-8") - except subprocess.CalledProcessError as ex: - raise CRMDCNotFound(str(ex)) - - current_dc = '' - for line in status.split('\n'): - if line.startswith('Current DC'): - # Current DC: juju-lytrusty-machine-2 (168108163) - partition with quorum - current_dc = line.split(':')[1].split()[0] - if current_dc == get_unit_hostname(): - return True - elif current_dc == 'NONE': - raise CRMDCNotFound('Current DC: NONE') - - return False - - -@retry_on_exception(5, base_delay=2, - exc_type=(CRMResourceNotFound, CRMDCNotFound)) -def is_crm_leader(resource, retry=False): - """ - Returns True if the charm calling this is the elected corosync leader, - as returned by calling the external "crm" command. - - We allow this operation to be retried to avoid the possibility of getting a - false negative. See LP #1396246 for more info. - """ - if resource == DC_RESOURCE_NAME: - return is_crm_dc() - cmd = ['crm', 'resource', 'show', resource] - try: - status = subprocess.check_output(cmd, stderr=subprocess.STDOUT) - if not isinstance(status, six.text_type): - status = six.text_type(status, "utf-8") - except subprocess.CalledProcessError: - status = None - - if status and get_unit_hostname() in status: - return True - - if status and "resource %s is NOT running" % (resource) in status: - raise CRMResourceNotFound("CRM resource %s not found" % (resource)) - - return False - - -def is_leader(resource): - log("is_leader is deprecated. Please consider using is_crm_leader " - "instead.", level=WARNING) - return is_crm_leader(resource) - - -def peer_units(peer_relation="cluster"): - peers = [] - for r_id in (relation_ids(peer_relation) or []): - for unit in (relation_list(r_id) or []): - peers.append(unit) - return peers - - -def peer_ips(peer_relation='cluster', addr_key='private-address'): - '''Return a dict of peers and their private-address''' - peers = {} - for r_id in relation_ids(peer_relation): - for unit in relation_list(r_id): - peers[unit] = relation_get(addr_key, rid=r_id, unit=unit) - return peers - - -def oldest_peer(peers): - """Determines who the oldest peer is by comparing unit numbers.""" - local_unit_no = int(os.getenv('JUJU_UNIT_NAME').split('/')[1]) - for peer in peers: - remote_unit_no = int(peer.split('/')[1]) - if remote_unit_no < local_unit_no: - return False - return True - - -def eligible_leader(resource): - log("eligible_leader is deprecated. Please consider using " - "is_elected_leader instead.", level=WARNING) - return is_elected_leader(resource) - - -def https(): - ''' - Determines whether enough data has been provided in configuration - or relation data to configure HTTPS - . - returns: boolean - ''' - use_https = config_get('use-https') - if use_https and bool_from_string(use_https): - return True - if config_get('ssl_cert') and config_get('ssl_key'): - return True - for r_id in relation_ids('identity-service'): - for unit in relation_list(r_id): - # TODO - needs fixing for new helper as ssl_cert/key suffixes with CN - rel_state = [ - relation_get('https_keystone', rid=r_id, unit=unit), - relation_get('ca_cert', rid=r_id, unit=unit), - ] - # NOTE: works around (LP: #1203241) - if (None not in rel_state) and ('' not in rel_state): - return True - return False - - -def determine_api_port(public_port, singlenode_mode=False): - ''' - Determine correct API server listening port based on - existence of HTTPS reverse proxy and/or haproxy. - - public_port: int: standard public port for given service - - singlenode_mode: boolean: Shuffle ports when only a single unit is present - - returns: int: the correct listening port for the API service - ''' - i = 0 - if singlenode_mode: - i += 1 - elif len(peer_units()) > 0 or is_clustered(): - i += 1 - if https(): - i += 1 - return public_port - (i * 10) - - -def determine_apache_port(public_port, singlenode_mode=False): - ''' - Description: Determine correct apache listening port based on public IP + - state of the cluster. - - public_port: int: standard public port for given service - - singlenode_mode: boolean: Shuffle ports when only a single unit is present - - returns: int: the correct listening port for the HAProxy service - ''' - i = 0 - if singlenode_mode: - i += 1 - elif len(peer_units()) > 0 or is_clustered(): - i += 1 - return public_port - (i * 10) - - -def get_hacluster_config(exclude_keys=None): - ''' - Obtains all relevant configuration from charm configuration required - for initiating a relation to hacluster: - - ha-bindiface, ha-mcastport, vip, os-internal-hostname, - os-admin-hostname, os-public-hostname, os-access-hostname - - param: exclude_keys: list of setting key(s) to be excluded. - returns: dict: A dict containing settings keyed by setting name. - raises: HAIncompleteConfig if settings are missing or incorrect. - ''' - settings = ['ha-bindiface', 'ha-mcastport', 'vip', 'os-internal-hostname', - 'os-admin-hostname', 'os-public-hostname', 'os-access-hostname'] - conf = {} - for setting in settings: - if exclude_keys and setting in exclude_keys: - continue - - conf[setting] = config_get(setting) - - if not valid_hacluster_config(): - raise HAIncorrectConfig('Insufficient or incorrect config data to ' - 'configure hacluster.') - return conf - - -def valid_hacluster_config(): - ''' - Check that either vip or dns-ha is set. If dns-ha then one of os-*-hostname - must be set. - - Note: ha-bindiface and ha-macastport both have defaults and will always - be set. We only care that either vip or dns-ha is set. - - :returns: boolean: valid config returns true. - raises: HAIncompatibileConfig if settings conflict. - raises: HAIncompleteConfig if settings are missing. - ''' - vip = config_get('vip') - dns = config_get('dns-ha') - if not(bool(vip) ^ bool(dns)): - msg = ('HA: Either vip or dns-ha must be set but not both in order to ' - 'use high availability') - status_set('blocked', msg) - raise HAIncorrectConfig(msg) - - # If dns-ha then one of os-*-hostname must be set - if dns: - dns_settings = ['os-internal-hostname', 'os-admin-hostname', - 'os-public-hostname', 'os-access-hostname'] - # At this point it is unknown if one or all of the possible - # network spaces are in HA. Validate at least one is set which is - # the minimum required. - for setting in dns_settings: - if config_get(setting): - log('DNS HA: At least one hostname is set {}: {}' - ''.format(setting, config_get(setting)), - level=DEBUG) - return True - - msg = ('DNS HA: At least one os-*-hostname(s) must be set to use ' - 'DNS HA') - status_set('blocked', msg) - raise HAIncompleteConfig(msg) - - log('VIP HA: VIP is set {}'.format(vip), level=DEBUG) - return True - - -def canonical_url(configs, vip_setting='vip'): - ''' - Returns the correct HTTP URL to this host given the state of HTTPS - configuration and hacluster. - - :configs : OSTemplateRenderer: A config tempating object to inspect for - a complete https context. - - :vip_setting: str: Setting in charm config that specifies - VIP address. - ''' - scheme = 'http' - if 'https' in configs.complete_contexts(): - scheme = 'https' - if is_clustered(): - addr = config_get(vip_setting) - else: - addr = unit_get('private-address') - return '%s://%s' % (scheme, addr) |