charm-rabbitmq-server/hooks/rabbit_utils.py

1205 lines
39 KiB
Python

# Copyright 2016 Canonical Ltd
#
# 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.
import json
import os
import re
import sys
import subprocess
import glob
import tempfile
import time
import shutil
import socket
from collections import OrderedDict
from rabbitmq_context import (
RabbitMQSSLContext,
RabbitMQClusterContext,
RabbitMQEnvContext,
)
from charmhelpers.core.templating import render
from charmhelpers.contrib.openstack.utils import (
_determine_os_workload_status,
get_hostname,
pause_unit,
resume_unit,
is_unit_paused_set,
)
from charmhelpers.contrib.hahelpers.cluster import (
distributed_wait,
)
from charmhelpers.core.hookenv import (
relation_id,
relation_ids,
related_units,
relations_for_id,
log, ERROR,
WARNING,
INFO, DEBUG,
service_name,
status_set,
cached,
relation_set,
relation_get,
application_version_set,
config,
is_leader,
leader_get,
local_unit,
)
from charmhelpers.core.host import (
pwgen,
mkdir,
write_file,
cmp_pkgrevno,
path_hash,
service as system_service,
)
from charmhelpers.contrib.peerstorage import (
peer_store,
peer_retrieve
)
from charmhelpers.fetch import (
apt_update,
apt_install,
)
from charmhelpers.fetch import get_upstream_version
PACKAGES = ['rabbitmq-server', 'python3-amqplib', 'lockfile-progs']
VERSION_PACKAGE = 'rabbitmq-server'
RABBITMQ_CTL = '/usr/sbin/rabbitmqctl'
COOKIE_PATH = '/var/lib/rabbitmq/.erlang.cookie'
ENV_CONF = '/etc/rabbitmq/rabbitmq-env.conf'
RABBITMQ_CONF = '/etc/rabbitmq/rabbitmq.config'
ENABLED_PLUGINS = '/etc/rabbitmq/enabled_plugins'
RABBIT_USER = 'rabbitmq'
LIB_PATH = '/var/lib/rabbitmq/'
HOSTS_FILE = '/etc/hosts'
_named_passwd = '/var/lib/charm/{}/{}.passwd'
_local_named_passwd = '/var/lib/charm/{}/{}.local_passwd'
# hook_contexts are used as a convenient mechanism to render templates
# logically, consider building a hook_context for template rendering so
# the charm doesn't concern itself with template specifics etc.
CONFIG_FILES = OrderedDict([
(RABBITMQ_CONF, {
'hook_contexts': [
RabbitMQSSLContext(),
RabbitMQClusterContext(),
],
'services': ['rabbitmq-server']
}),
(ENV_CONF, {
'hook_contexts': [
RabbitMQEnvContext(),
],
'services': ['rabbitmq-server']
}),
(ENABLED_PLUGINS, {
'hook_contexts': None,
'services': ['rabbitmq-server']
}),
])
class ConfigRenderer(object):
"""
This class is a generic configuration renderer for
a given dict mapping configuration files and hook_contexts.
"""
def __init__(self, config):
"""
:param config: see CONFIG_FILES
:type config: dict
"""
self.config_data = {}
for config_path, data in config.items():
hook_contexts = data.get('hook_contexts', None)
if hook_contexts:
ctxt = {}
for svc_context in hook_contexts:
ctxt.update(svc_context())
self.config_data[config_path] = ctxt
def write(self, config_path):
data = self.config_data.get(config_path, None)
if data:
log("writing config file: %s , data: %s" % (config_path,
str(data)),
level='DEBUG')
render(os.path.basename(config_path), config_path,
data, perms=0o644)
def write_all(self):
"""Write all the defined configuration files"""
for service in self.config_data.keys():
self.write(service)
def complete_contexts(self):
return []
class RabbitmqError(Exception):
pass
def list_vhosts():
"""
Returns a list of all the available vhosts
"""
try:
cmd = [RABBITMQ_CTL, 'list_vhosts']
# NOTE(ajkavanagh): In focal and above, rabbitmq-server now has a
# --formatter option.
if caching_cmp_pkgrevno('rabbitmq-server', '3.8.2') >= 0:
cmd.append('--formatter=json')
output = subprocess.check_output(cmd)
output = output.decode('utf-8')
if caching_cmp_pkgrevno('rabbitmq-server', '3.8.2') >= 0:
decoded = json.loads(output)
return [l['name'] for l in decoded]
# NOTE(jamespage): Earlier rabbitmqctl versions append "...done"
# to the output of list_vhosts
elif '...done' in output:
return output.split('\n')[1:-2]
else:
return output.split('\n')[1:-1]
except Exception as ex:
# if no vhosts, just raises an exception
log(str(ex), level='DEBUG')
return []
def vhost_queue_info(vhost):
"""Provide a list of queue info objects for the given vhost in RabbitMQ
Each object provides name (str), messages (int), and consumers (int)
@raises CalledProcessError on failure to list_queues of the vhost
"""
cmd = [RABBITMQ_CTL, '-p', vhost, 'list_queues',
'name', 'messages', 'consumers']
# NOTE(ajkavanagh): In focal and above, rabbitmq-server now has a
# --formatter option.
if caching_cmp_pkgrevno('rabbitmq-server', '3.8.2') >= 0:
cmd.append('--formatter=json')
output = subprocess.check_output(cmd).decode('utf-8')
queue_info = []
if caching_cmp_pkgrevno('rabbitmq-server', '3.8.2') >= 0:
decoded = json.loads(output)
# note that the json is already in the desired output of queue_info
# below
return decoded
# NOTE(jamespage): Earlier rabbitmqctl versions append "...done"
# to the output of list_queues
elif '...done' in output:
queues = output.split('\n')[1:-2]
else:
queues = output.split('\n')[1:-1]
for queue in queues:
[qname, qmsgs, qconsumers] = queue.split()
queue_info.append({
'name': qname,
'messages': int(qmsgs),
'consumers': int(qconsumers)
})
return queue_info
def vhost_exists(vhost):
return vhost in list_vhosts()
def create_vhost(vhost):
if vhost_exists(vhost):
return
rabbitmqctl('add_vhost', vhost)
log('Created new vhost (%s).' % vhost)
def user_exists(user):
cmd = [RABBITMQ_CTL, 'list_users']
# NOTE(ajkavanagh): In focal and above, rabbitmq-server now has a
# --formatter option.
if caching_cmp_pkgrevno('rabbitmq-server', '3.8.2') >= 0:
cmd.append('--formatter=json')
out = subprocess.check_output(cmd).decode('utf-8')
decoded = json.loads(out)
users = [l['user'] for l in decoded]
return user in users
# NOTE(ajkavanagh): pre 3.8.2 the code needs to deal with just a text
# output
out = subprocess.check_output(cmd).decode('utf-8')
lines = out.split('\n')[1:]
for line in lines:
_user = line.split('\t')[0]
if _user == user:
return True
return False
def create_user(user, password, tags=[]):
exists = user_exists(user)
if not exists:
log('Creating new user (%s).' % user)
rabbitmqctl('add_user', user, password)
if 'administrator' in tags:
log('Granting admin access to {}'.format(user))
log('Adding tags [{}] to user {}'.format(
', '.join(tags),
user
))
rabbitmqctl('set_user_tags', user, ' '.join(tags))
def grant_permissions(user, vhost):
log("Granting permissions", level='DEBUG')
rabbitmqctl('set_permissions', '-p',
vhost, user, '.*', '.*', '.*')
def set_policy(vhost, policy_name, match, value):
log("setting policy", level='DEBUG')
rabbitmqctl('set_policy', '-p', vhost,
policy_name, match, value)
@cached
def caching_cmp_pkgrevno(package, revno, pkgcache=None):
return cmp_pkgrevno(package, revno, pkgcache)
def set_ha_mode(vhost, mode, params=None, sync_mode='automatic'):
"""Valid mode values:
* 'all': Queue is mirrored across all nodes in the cluster. When a new
node is added to the cluster, the queue will be mirrored to that node.
* 'exactly': Queue is mirrored to count nodes in the cluster.
* 'nodes': Queue is mirrored to the nodes listed in node names
More details at http://www.rabbitmq.com./ha.html
:param vhost: virtual host name
:param mode: ha mode
:param params: values to pass to the policy, possible values depend on the
mode chosen.
:param sync_mode: when `mode` is 'exactly' this used to indicate how the
sync has to be done
http://www.rabbitmq.com./ha.html#eager-synchronisation
"""
if caching_cmp_pkgrevno('rabbitmq-server', '3.0.0') < 0:
log(("Mirroring queues cannot be enabled, only supported "
"in rabbitmq-server >= 3.0"), level=WARNING)
log(("More information at http://www.rabbitmq.com/blog/"
"2012/11/19/breaking-things-with-rabbitmq-3-0"), level='INFO')
return
if mode == 'all':
value = '{"ha-mode": "all", "ha-sync-mode": "%s"}' % sync_mode
elif mode == 'exactly':
value = '{"ha-mode":"exactly","ha-params":%s,"ha-sync-mode":"%s"}' \
% (params, sync_mode)
elif mode == 'nodes':
value = '{"ha-mode":"nodes","ha-params":[%s]},"ha-sync-mode": "%s"' % (
",".join(params), sync_mode)
else:
raise RabbitmqError(("Unknown mode '%s', known modes: "
"all, exactly, nodes"))
log("Setting HA policy to vhost '%s'" % vhost, level='INFO')
set_policy(vhost, 'HA', r'^(?!amq\.).*', value)
def clear_ha_mode(vhost, name='HA', force=False):
"""
Clear policy from the `vhost` by `name`
"""
if cmp_pkgrevno('rabbitmq-server', '3.0.0') < 0:
log(("Mirroring queues not supported "
"in rabbitmq-server >= 3.0"), level=WARNING)
log(("More information at http://www.rabbitmq.com/blog/"
"2012/11/19/breaking-things-with-rabbitmq-3-0"), level='INFO')
return
log("Clearing '%s' policy from vhost '%s'" % (name, vhost), level='INFO')
try:
rabbitmqctl('clear_policy', '-p', vhost, name)
except subprocess.CalledProcessError as ex:
if not force:
raise ex
def set_all_mirroring_queues(enable):
"""
:param enable: if True then enable mirroring queue for all the vhosts,
otherwise the HA policy is removed
"""
if cmp_pkgrevno('rabbitmq-server', '3.0.0') < 0:
log(("Mirroring queues not supported "
"in rabbitmq-server >= 3.0"), level=WARNING)
log(("More information at http://www.rabbitmq.com/blog/"
"2012/11/19/breaking-things-with-rabbitmq-3-0"), level='INFO')
return
if enable:
status_set('active', 'Enabling queue mirroring')
else:
status_set('active', 'Disabling queue mirroring')
for vhost in list_vhosts():
if enable:
set_ha_mode(vhost, 'all')
else:
clear_ha_mode(vhost, force=True)
def rabbitmqctl(action, *args):
''' Run rabbitmqctl with action and args. This function uses
subprocess.check_call. For uses that need check_output
use a direct subprocess call or rabbitmqctl_normalized_output
function.
'''
cmd = []
# wait will run for ever. Timeout in a reasonable amount of time
if 'wait' in action:
cmd.extend(["timeout", "180"])
cmd.extend([RABBITMQ_CTL, action])
for arg in args:
cmd.append(arg)
log("Running {}".format(cmd), 'DEBUG')
subprocess.check_call(cmd)
def configure_notification_ttl(vhost, ttl=3600000):
''' Configure 1h minute TTL for notfication topics in the provided vhost
This is a workaround for filling notification queues in OpenStack
until a more general service discovery mechanism exists so that
notifications can be enabled/disabled on each individual service.
'''
rabbitmqctl('set_policy',
'TTL', '^(versioned_)?notifications.*',
'{{"message-ttl":{ttl}}}'.format(ttl=ttl),
'--priority', '1',
'--apply-to', 'queues',
'-p', vhost)
def rabbitmqctl_normalized_output(*args):
''' Run rabbitmqctl with args. Normalize output by removing
whitespace and return it to caller for further processing.
'''
cmd = [RABBITMQ_CTL]
cmd.extend(args)
out = (subprocess
.check_output(cmd, stderr=subprocess.STDOUT)
.decode('utf-8'))
# Output is in Erlang External Term Format (ETF). The amount of whitespace
# (including newlines in the middle of data structures) in the output
# depends on the data presented. ETF resembles JSON, but it is not.
# Writing our own parser is a bit out of scope, enabling management-plugin
# to use REST interface might be overkill at this stage.
#
# Removing whitespace will let our simple pattern matching work and is a
# compromise.
return out.translate(str.maketrans(dict.fromkeys(' \t\n')))
def wait_app():
''' Wait until rabbitmq has fully started '''
run_dir = '/var/run/rabbitmq/'
if os.path.isdir(run_dir):
pid_file = run_dir + 'pid'
else:
pid_file = '/var/lib/rabbitmq/mnesia/rabbit@' \
+ socket.gethostname() + '.pid'
log('Waiting for rabbitmq app to start: {}'.format(pid_file), DEBUG)
try:
rabbitmqctl('wait', pid_file)
log('Confirmed rabbitmq app is running', DEBUG)
return True
except subprocess.CalledProcessError as ex:
status_set('blocked', 'RabbitMQ failed to start')
try:
status_cmd = ['rabbitmqctl', 'status']
log(subprocess.check_output(status_cmd).decode('utf-8'), DEBUG)
except Exception:
pass
raise ex
def cluster_wait():
''' Wait for operations based on modulo distribution
Use the distributed_wait function to determine how long to wait before
running an operation like restart or cluster join. By setting modulo to
the exact number of nodes in the cluster we get serial operations.
Check for explicit configuration parameters for modulo distribution.
The config setting modulo-nodes has first priority. If modulo-nodes is not
set, check min-cluster-size. Finally, if neither value is set, determine
how many peers there are from the cluster relation.
@side_effect: distributed_wait is called which calls time.sleep()
@return: None
'''
wait = config('known-wait')
if config('modulo-nodes') is not None:
# modulo-nodes has first priority
num_nodes = config('modulo-nodes')
elif config('min-cluster-size'):
# min-cluster-size is consulted next
num_nodes = config('min-cluster-size')
else:
# If nothing explicit is configured, determine cluster size based on
# peer relations
num_nodes = 1
for rid in relation_ids('cluster'):
num_nodes += len(related_units(rid))
distributed_wait(modulo=num_nodes, wait=wait)
def start_app():
''' Start the rabbitmq app and wait until it is fully started '''
status_set('maintenance', 'Starting rabbitmq application')
rabbitmqctl('start_app')
wait_app()
def join_cluster(node):
''' Join cluster with node '''
if cmp_pkgrevno('rabbitmq-server', '3.0.1') >= 0:
cluster_cmd = 'join_cluster'
else:
cluster_cmd = 'cluster'
status_set('maintenance',
'Clustering with remote rabbit host (%s).' % node)
rabbitmqctl('stop_app')
# Intentionally using check_output so we can see rabbitmqctl error
# message if it fails
cmd = [RABBITMQ_CTL, cluster_cmd, node]
subprocess.check_output(cmd, stderr=subprocess.STDOUT)
start_app()
log('Host clustered with %s.' % node, 'INFO')
def cluster_with():
if is_unit_paused_set():
log("Do not run cluster_with while unit is paused", "WARNING")
return
log('Clustering with new node')
# check the leader and try to cluster with it
node = leader_node()
if node:
if node in running_nodes():
log('Host already clustered with %s.' % node)
cluster_rid = relation_id('cluster', local_unit())
is_clustered = relation_get(attribute='clustered',
rid=cluster_rid,
unit=local_unit())
log('am I clustered?: %s' % bool(is_clustered), level=DEBUG)
if not is_clustered:
# NOTE(freyes): this node needs to be marked as clustered, it's
# part of the cluster according to 'rabbitmqctl cluster_status'
# (LP: #1691510)
relation_set(relation_id=cluster_rid,
clustered=get_unit_hostname(),
timestamp=time.time())
return False
# NOTE: The primary problem rabbitmq has clustering is when
# more than one node attempts to cluster at the same time.
# The asynchronous nature of hook firing nearly guarantees
# this. Using cluster_wait based on modulo_distribution
cluster_wait()
try:
join_cluster(node)
# NOTE: toggle the cluster relation to ensure that any peers
# already clustered re-assess status correctly
relation_set(clustered=get_unit_hostname(), timestamp=time.time())
return True
except subprocess.CalledProcessError as e:
status_set('blocked', 'Failed to cluster with %s. Exception: %s'
% (node, e))
start_app()
else:
status_set('waiting', 'Leader not available for clustering')
return False
return False
def check_cluster_memberships():
''' Iterate over RabbitMQ node list, compare it to charm cluster
relationships, and forget about any nodes previously abruptly removed
from the cluster '''
for rid in relation_ids('cluster'):
for node in nodes():
if not any(rel.get('clustered', None) == node.split('@')[1]
for rel in relations_for_id(relid=rid)) and \
node not in running_nodes():
log("check_cluster_memberships(): '{}' in nodes but not in "
"charm relations or running_nodes, telling RabbitMQ to "
"forget about it.".format(node), level=DEBUG)
forget_cluster_node(node)
def forget_cluster_node(node):
''' Remove previously departed node from cluster '''
if cmp_pkgrevno('rabbitmq-server', '3.0.0') < 0:
log('rabbitmq-server version < 3.0.0, '
'forget_cluster_node not supported.', level=DEBUG)
return
try:
rabbitmqctl('forget_cluster_node', node)
except subprocess.CalledProcessError as e:
if e.returncode == 2:
log("Unable to remove node '{}' from cluster. It is either still "
"running or already removed. (Output: '{}')"
"".format(node, e.output), level=ERROR)
return
else:
raise
log("Removed previously departed node from cluster: '{}'."
"".format(node), level=INFO)
def leave_cluster():
''' Leave cluster gracefully '''
try:
rabbitmqctl('stop_app')
rabbitmqctl('reset')
start_app()
log('Successfully left cluster gracefully.')
except Exception:
# error, no nodes available for clustering
log('Cannot leave cluster, we might be the last disc-node in the '
'cluster.', level=ERROR)
raise
def _manage_plugin(plugin, action):
os.environ['HOME'] = '/root'
_rabbitmq_plugins = \
glob.glob('/usr/lib/rabbitmq/lib/rabbitmq_server-*'
'/sbin/rabbitmq-plugins')[0]
subprocess.check_call([_rabbitmq_plugins, action, plugin])
def enable_plugin(plugin):
_manage_plugin(plugin, 'enable')
def disable_plugin(plugin):
_manage_plugin(plugin, 'disable')
def get_managment_port():
if get_upstream_version(VERSION_PACKAGE) >= '3':
return 15672
else:
return 55672
def execute(cmd, die=False, echo=False):
""" Executes a command
if die=True, script will exit(1) if command does not return 0
if echo=True, output of command will be printed to stdout
returns a tuple: (stdout, stderr, return code)
"""
p = subprocess.Popen(cmd.split(" "),
stdout=subprocess.PIPE,
stdin=subprocess.PIPE,
stderr=subprocess.PIPE)
stdout = ""
stderr = ""
def print_line(l):
if echo:
print(l.strip('\n'))
sys.stdout.flush()
for l in iter(p.stdout.readline, ''):
print_line(l)
stdout += l
for l in iter(p.stderr.readline, ''):
print_line(l)
stderr += l
p.communicate()
rc = p.returncode
if die and rc != 0:
log("command %s return non-zero." % cmd, level=ERROR)
return (stdout, stderr, rc)
def get_rabbit_password_on_disk(username, password=None, local=False):
''' Retrieve, generate or store a rabbit password for
the provided username on disk'''
if local:
_passwd_file = _local_named_passwd.format(service_name(), username)
else:
_passwd_file = _named_passwd.format(service_name(), username)
_password = None
if os.path.exists(_passwd_file):
with open(_passwd_file, 'r') as passwd:
_password = passwd.read().strip()
else:
mkdir(os.path.dirname(_passwd_file), owner=RABBIT_USER,
group=RABBIT_USER, perms=0o775)
os.chmod(os.path.dirname(_passwd_file), 0o775)
_password = password or pwgen(length=64)
write_file(_passwd_file, _password, owner=RABBIT_USER,
group=RABBIT_USER, perms=0o660)
return _password
def migrate_passwords_to_peer_relation():
'''Migrate any passwords storage on disk to cluster peer relation'''
for f in glob.glob('/var/lib/charm/{}/*.passwd'.format(service_name())):
_key = os.path.basename(f)
with open(f, 'r') as passwd:
_value = passwd.read().strip()
try:
peer_store(_key, _value)
os.unlink(f)
except ValueError:
# NOTE cluster relation not yet ready - skip for now
pass
def get_rabbit_password(username, password=None, local=False):
''' Retrieve, generate or store a rabbit password for
the provided username using peer relation cluster'''
if local:
return get_rabbit_password_on_disk(username, password, local)
else:
migrate_passwords_to_peer_relation()
_key = '{}.passwd'.format(username)
try:
_password = peer_retrieve(_key)
if _password is None:
_password = password or pwgen(length=64)
peer_store(_key, _password)
except ValueError:
# cluster relation is not yet started, use on-disk
_password = get_rabbit_password_on_disk(username, password)
return _password
def update_hosts_file(map):
"""Rabbitmq does not currently like ipv6 addresses so we need to use dns
names instead. In order to make them resolvable we ensure they are in
/etc/hosts.
"""
with open(HOSTS_FILE, 'r') as hosts:
lines = hosts.readlines()
log("Updating hosts file with: %s (current: %s)" % (map, lines),
level=INFO)
newlines = []
for ip, hostname in map.items():
if not ip or not hostname:
continue
keepers = []
for line in lines:
_line = line.split()
if len(line) < 2 or not (_line[0] == ip or hostname in _line[1:]):
keepers.append(line)
else:
log("Removing line '%s' from hosts file" % (line))
lines = keepers
newlines.append("%s %s\n" % (ip, hostname))
lines += newlines
with tempfile.NamedTemporaryFile(delete=False) as tmpfile:
with open(tmpfile.name, 'w') as hosts:
for line in lines:
hosts.write(line)
shutil.move(tmpfile.name, HOSTS_FILE)
os.chmod(HOSTS_FILE, 0o644)
def restart_map():
'''Determine the correct resource map to be passed to
charmhelpers.core.restart_on_change() based on the services configured.
:returns: dict: A dictionary mapping config file to lists of services
that should be restarted when file changes.
'''
_map = []
for f, ctxt in CONFIG_FILES.items():
svcs = []
for svc in ctxt['services']:
svcs.append(svc)
if svcs:
_map.append((f, svcs))
return OrderedDict(_map)
def services():
''' Returns a list of services associate with this charm '''
_services = []
for v in restart_map().values():
_services = _services + v
return list(set(_services))
@cached
def nodes(get_running=False):
''' Get list of nodes registered in the RabbitMQ cluster '''
# NOTE(ajkavanagh): In focal and above, rabbitmq-server now has a
# --formatter option.
if caching_cmp_pkgrevno('rabbitmq-server', '3.8.2') >= 0:
cmd = [RABBITMQ_CTL, 'cluster_status', '--formatter=json']
output = subprocess.check_output(cmd).decode('utf-8')
decoded = json.loads(output)
if get_running:
return decoded['running_nodes']
return decoded['disk_nodes'] + decoded['ram_nodes']
out = rabbitmqctl_normalized_output('cluster_status')
cluster_status = {}
for m in re.finditer(r"{([^,]+),(?!\[{)\[([^\]]*)", out):
state = m.group(1)
items = m.group(2).split(',')
items = [x.replace("'", '').strip() for x in items]
cluster_status.update({state: items})
if get_running:
return cluster_status.get('running_nodes', [])
return cluster_status.get('disc', []) + cluster_status.get('ram', [])
@cached
def running_nodes():
''' Determine the current set of running nodes in the RabbitMQ cluster '''
return nodes(get_running=True)
@cached
def leader_node():
''' Provide the leader node for clustering
@returns leader node's hostname or None
'''
# Each rabbitmq node should join_cluster with the leader
# to avoid split-brain clusters.
try:
leader_node_hostname = peer_retrieve('leader_node_hostname')
except ValueError:
# This is a single unit
return None
if leader_node_hostname:
return "rabbit@" + leader_node_hostname
else:
return None
def get_node_hostname(ip_addr):
''' Resolve IP address to hostname '''
try:
nodename = get_hostname(ip_addr, fqdn=False)
except Exception:
log('Cannot resolve hostname for %s using DNS servers' % ip_addr,
level=WARNING)
log('Falling back to use socket.gethostname()',
level=WARNING)
# If the private-address is not resolvable using DNS
# then use the current hostname
nodename = socket.gethostname()
log('local nodename: %s' % nodename, level=INFO)
return nodename
@cached
def clustered():
''' Determine whether local rabbitmq-server is clustered '''
# NOTE: A rabbitmq node can only join a cluster once.
# Simply checking for more than one running node tells us
# if this unit is in a cluster.
if len(running_nodes()) > 1:
return True
else:
return False
def assess_cluster_status(*args):
''' Assess the status for the current running unit '''
if is_unit_paused_set():
return "maintenance", "Paused"
# NOTE: ensure rabbitmq is actually installed before doing
# any checks
if rabbitmq_is_installed():
# Clustering Check
if not is_sufficient_peers():
return 'waiting', ("Waiting for all {} peers to complete the "
"cluster.".format(config('min-cluster-size')))
peer_ids = relation_ids('cluster')
if peer_ids and len(related_units(peer_ids[0])):
if not clustered():
return 'waiting', 'Unit has peers, but RabbitMQ not clustered'
# General status check
ret = wait_app()
if ret:
# we're active - so just return the 'active' state, but if 'active'
# is returned, then it is ignored by the assess_status system.
return 'active', "message is ignored"
else:
return 'waiting', 'RabbitMQ is not yet installed'
def restart_on_change(restart_map, stopstart=False):
"""Restart services based on configuration files changing
This function is used a decorator, for example::
@restart_on_change({
'/etc/ceph/ceph.conf': [ 'cinder-api', 'cinder-volume' ]
'/etc/apache/sites-enabled/*': [ 'apache2' ]
})
def config_changed():
pass # your code here
In this example, the cinder-api and cinder-volume services
would be restarted if /etc/ceph/ceph.conf is changed by the
ceph_client_changed function. The apache2 service would be
restarted if any file matching the pattern got changed, created
or removed. Standard wildcards are supported, see documentation
for the 'glob' module for more information.
"""
def wrap(f):
def wrapped_f(*args, **kwargs):
if is_unit_paused_set():
return f(*args, **kwargs)
checksums = {path: path_hash(path) for path in restart_map}
f(*args, **kwargs)
restarts = []
for path in restart_map:
if path_hash(path) != checksums[path]:
restarts += restart_map[path]
services_list = list(OrderedDict.fromkeys(restarts))
cluster_wait()
if not stopstart:
for svc_name in services_list:
system_service('restart', svc_name)
wait_app()
else:
for action in ['stop', 'start']:
for svc_name in services_list:
system_service(action, svc_name)
wait_app()
return wrapped_f
return wrap
def assess_status(configs):
"""Assess status of current unit
Decides what the state of the unit should be based on the current
configuration.
SIDE EFFECT: calls set_os_workload_status(...) which sets the workload
status of the unit.
Also calls status_set(...) directly if paused state isn't complete.
@param configs: a templating.OSConfigRenderer() object
@returns None - this function is executed for its side-effect
"""
assess_status_func(configs)()
rmq_version = get_upstream_version(VERSION_PACKAGE)
if rmq_version:
application_version_set(rmq_version)
def assess_status_func(configs):
"""Helper function to create the function that will assess_status() for
the unit.
Uses charmhelpers.contrib.openstack.utils.make_assess_status_func() to
create the appropriate status function and then returns it.
Used directly by assess_status() and also for pausing and resuming
the unit.
NOTE(ajkavanagh) ports are not checked due to race hazards with services
that don't behave sychronously w.r.t their service scripts. e.g.
apache2.
@param configs: a templating.OSConfigRenderer() object
@return f() -> None : a function that assesses the unit's workload status
"""
def _assess_status_func():
state, message = _determine_os_workload_status(
configs, {},
charm_func=assess_cluster_status,
services=services(), ports=None)
if state == 'active' and clustered():
message = 'Unit is ready and clustered'
# Remind the administrator cluster_series_upgrading is set.
# If the cluster has completed the series upgrade, run the
# complete-cluster-series-upgrade action to clear this setting.
if leader_get('cluster_series_upgrading'):
message += (", Run complete-cluster-series-upgrade when the "
"cluster has completed its upgrade.")
# Edge case when the first rabbitmq unit is upgraded it will show
# waiting for peers. Force "active" workload state for various
# testing suites like zaza to recognize a successful series upgrade
# of the first unit.
if state == "waiting":
state = "active"
status_set(state, message)
return _assess_status_func
def pause_unit_helper(configs):
"""Helper function to pause a unit, and then call assess_status(...) in
effect, so that the status is correctly updated.
Uses charmhelpers.contrib.openstack.utils.pause_unit() to do the work.
@param configs: a templating.OSConfigRenderer() object
@returns None - this function is executed for its side-effect
"""
_pause_resume_helper(pause_unit, configs)
def resume_unit_helper(configs):
"""Helper function to resume a unit, and then call assess_status(...) in
effect, so that the status is correctly updated.
Uses charmhelpers.contrib.openstack.utils.resume_unit() to do the work.
@param configs: a templating.OSConfigRenderer() object
@returns None - this function is executed for its side-effect
"""
_pause_resume_helper(resume_unit, configs)
def _pause_resume_helper(f, configs):
"""Helper function that uses the make_assess_status_func(...) from
charmhelpers.contrib.openstack.utils to create an assess_status(...)
function that can be used with the pause/resume of the unit
@param f: the function to be used with the assess_status(...) function
@returns None - this function is executed for its side-effect
"""
# TODO(ajkavanagh) - ports= has been left off because of the race hazard
# that exists due to service_start()
f(assess_status_func(configs),
services=services(),
ports=None)
def get_unit_hostname():
"""Return this unit's hostname.
@returns hostname
"""
return socket.gethostname()
def is_sufficient_peers():
"""Sufficient number of expected peers to build a complete cluster
If min-cluster-size has been provided, check that we have sufficient
number of peers who have presented a hostname for a complete cluster.
If not defined assume a single unit.
@returns boolean
"""
min_size = config('min-cluster-size')
if min_size:
log("Checking for minimum of {} peer units".format(min_size),
level=DEBUG)
# Include this unit
units = 1
for rid in relation_ids('cluster'):
for unit in related_units(rid):
if relation_get(attribute='hostname',
rid=rid, unit=unit):
units += 1
if units < min_size:
log("Insufficient number of peer units to form cluster "
"(expected=%s, got=%s)" % (min_size, units), level=INFO)
return False
else:
log("Sufficient number of peer units to form cluster {}"
"".format(min_size, level=DEBUG))
return True
else:
log("min-cluster-size is not defined, race conditions may occur if "
"this is not a single unit deployment.", level=WARNING)
return True
def rabbitmq_is_installed():
"""Determine if rabbitmq is installed
@returns boolean
"""
return os.path.exists(RABBITMQ_CTL)
def cluster_ready():
"""Determine if each node in the cluster is ready and the cluster is
complete with the expected number of peers.
Once cluster_ready returns True it is safe to execute client relation
hooks. Having min-cluster-size set will guarantee cluster_ready will not
return True until the expected number of peers are clustered and ready.
If min-cluster-size is not set it must assume the cluster is ready in order
to allow for single unit deployments.
@returns boolean
"""
min_size = config('min-cluster-size')
units = 1
for rid in relation_ids('cluster'):
units += len(related_units(rid))
if not min_size:
min_size = units
if not is_sufficient_peers():
return False
elif min_size > 1:
if not clustered():
return False
clustered_units = 1
for rid in relation_ids('cluster'):
for remote_unit in related_units(rid):
if not relation_get(attribute='clustered',
rid=rid,
unit=remote_unit):
log("{} is not yet clustered".format(remote_unit),
DEBUG)
return False
else:
clustered_units += 1
if clustered_units < min_size:
log("Fewer than minimum cluster size:{} rabbit units reporting "
"clustered".format(min_size),
DEBUG)
return False
else:
log("All {} rabbit units reporting clustered"
"".format(min_size),
DEBUG)
return True
log("Must assume this is a single unit returning 'cluster' ready", DEBUG)
return True
def client_node_is_ready():
"""Determine if the leader node has set amqp client data
@returns boolean
"""
# Bail if this unit is paused
if is_unit_paused_set():
return False
for rid in relation_ids('amqp'):
if leader_get(attribute='{}_password'.format(rid)):
return True
return False
def leader_node_is_ready():
"""Determine if the leader node is ready to handle client relationship
hooks.
IFF rabbit is not paused, is installed, this is the leader node and the
cluster is complete.
@returns boolean
"""
# Paused check must run before other checks
# Bail if this unit is paused
if is_unit_paused_set():
return False
return (rabbitmq_is_installed() and
is_leader() and
cluster_ready())
def archive_upgrade_available():
"""Check if the change in sources.list would warrant running
apt-get update/upgrade
@returns boolean:
True: the "source" had changed, so upgrade is available
False: the "source" had not changed, no upgrade needed
"""
log('checking if upgrade is available', DEBUG)
c = config()
old_source = c.previous('source')
log('Previous "source" config options was: {}'.format(old_source), DEBUG)
new_source = c['source']
log('Current "source" config options is: {}'.format(new_source), DEBUG)
if old_source != new_source:
log('The "source" config option change warrants the upgrade.', INFO)
return old_source != new_source
def install_or_upgrade_packages():
"""Run apt-get update/upgrade mantra.
This is called from either install hook, or from config-changed,
if upgrade is warranted
"""
status_set('maintenance', 'Installing/upgrading RabbitMQ packages')
apt_update(fatal=True)
apt_install(PACKAGES, fatal=True)