Merge lp:~1chb1n/charms/trusty/mongodb/sync-fetch-helpers-liberty into lp:charms/trusty/mongodb

[Ryan Beisner]

Sync hooks/charmhelpers for liberty cloud archive enablement.

Resolves:
2015-08-26 13:00:47 INFO install charmhelpers.fetch.SourceConfigError: Unsupported cloud: source option trusty-liberty/proposed

[uosci-testing-bot (uosci-testing-bot)]

charm_lint_check #8336 mongodb for 1chb1n mp268413
    LINT OK: passed

Build: http://10.245.162.77:8080/job/charm_lint_check/8336/

[uosci-testing-bot (uosci-testing-bot)]

charm_unit_test #7733 mongodb for 1chb1n mp268413
    UNIT OK: passed

Build: http://10.245.162.77:8080/job/charm_unit_test/7733/

[uosci-testing-bot (uosci-testing-bot)]

charm_amulet_test #5878 mongodb for 1chb1n mp268413
    AMULET OK: passed

Build: http://10.245.162.77:8080/job/charm_amulet_test/5878/

[lp:~1chb1n/charms/trusty/mongodb/sync-fetch-helpers-liberty]

77. By Ryan Beisner on 2015-08-19

resync all hooks/charmhelpers

[uosci-testing-bot (uosci-testing-bot)]

charm_lint_check #8364 mongodb for 1chb1n mp268413
    LINT OK: passed

Build: http://10.245.162.77:8080/job/charm_lint_check/8364/

[uosci-testing-bot (uosci-testing-bot)]

charm_unit_test #7762 mongodb for 1chb1n mp268413
    UNIT OK: passed

Build: http://10.245.162.77:8080/job/charm_unit_test/7762/

[uosci-testing-bot (uosci-testing-bot)]

charm_amulet_test #5908 mongodb for 1chb1n mp268413
    AMULET OK: passed

Build: http://10.245.162.77:8080/job/charm_amulet_test/5908/

[Liam Young (gnuoy)]

Approve

review: Approve

=== modified file 'hooks/charmhelpers/contrib/charmsupport/nrpe.py'
--- hooks/charmhelpers/contrib/charmsupport/nrpe.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/contrib/charmsupport/nrpe.py	2015-08-19 13:58:57 +0000
@@ -247,7 +247,9 @@
 
         service('restart', 'nagios-nrpe-server')
 
-        for rid in relation_ids("local-monitors"):
+        monitor_ids = relation_ids("local-monitors") + \
+            relation_ids("nrpe-external-master")
+        for rid in monitor_ids:
             relation_set(relation_id=rid, monitors=yaml.dump(monitors))
 
 

=== modified file 'hooks/charmhelpers/contrib/hahelpers/cluster.py'
--- hooks/charmhelpers/contrib/hahelpers/cluster.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/contrib/hahelpers/cluster.py	2015-08-19 13:58:57 +0000
@@ -44,6 +44,7 @@
     ERROR,
     WARNING,
     unit_get,
+    is_leader as juju_is_leader
 )
 from charmhelpers.core.decorators import (
     retry_on_exception,
@@ -52,6 +53,8 @@
     bool_from_string,
 )
 
+DC_RESOURCE_NAME = 'DC'
+
 
 class HAIncompleteConfig(Exception):
     pass
@@ -61,17 +64,30 @@
     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 the charm is part of a corosync cluster, call corosync to
+        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.
-        2. If the charm is not part of a corosync cluster, the leader is
+        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)
@@ -95,7 +111,33 @@
     return False
 
 
-@retry_on_exception(5, base_delay=2, exc_type=CRMResourceNotFound)
+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,
@@ -104,6 +146,8 @@
     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)

=== modified file 'hooks/charmhelpers/contrib/python/packages.py'
--- hooks/charmhelpers/contrib/python/packages.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/contrib/python/packages.py	2015-08-19 13:58:57 +0000
@@ -17,8 +17,11 @@
 # You should have received a copy of the GNU Lesser General Public License
 # along with charm-helpers.  If not, see <http://www.gnu.org/licenses/>.
 
+import os
+import subprocess
+
 from charmhelpers.fetch import apt_install, apt_update
-from charmhelpers.core.hookenv import log
+from charmhelpers.core.hookenv import charm_dir, log
 
 try:
     from pip import main as pip_execute
@@ -33,6 +36,8 @@
 def parse_options(given, available):
     """Given a set of options, check if available"""
     for key, value in sorted(given.items()):
+        if not value:
+            continue
         if key in available:
             yield "--{0}={1}".format(key, value)
 
@@ -51,11 +56,15 @@
     pip_execute(command)
 
 
-def pip_install(package, fatal=False, upgrade=False, **options):
+def pip_install(package, fatal=False, upgrade=False, venv=None, **options):
     """Install a python package"""
-    command = ["install"]
+    if venv:
+        venv_python = os.path.join(venv, 'bin/pip')
+        command = [venv_python, "install"]
+    else:
+        command = ["install"]
 
-    available_options = ('proxy', 'src', 'log', "index-url", )
+    available_options = ('proxy', 'src', 'log', 'index-url', )
     for option in parse_options(options, available_options):
         command.append(option)
 
@@ -69,7 +78,10 @@
 
     log("Installing {} package with options: {}".format(package,
                                                         command))
-    pip_execute(command)
+    if venv:
+        subprocess.check_call(command)
+    else:
+        pip_execute(command)
 
 
 def pip_uninstall(package, **options):
@@ -94,3 +106,16 @@
     """Returns the list of current python installed packages
     """
     return pip_execute(["list"])
+
+
+def pip_create_virtualenv(path=None):
+    """Create an isolated Python environment."""
+    apt_install('python-virtualenv')
+
+    if path:
+        venv_path = path
+    else:
+        venv_path = os.path.join(charm_dir(), 'venv')
+
+    if not os.path.exists(venv_path):
+        subprocess.check_call(['virtualenv', venv_path])

=== added file 'hooks/charmhelpers/core/files.py'
--- hooks/charmhelpers/core/files.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/files.py	2015-08-19 13:58:57 +0000
@@ -0,0 +1,45 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2014-2015 Canonical Limited.
+#
+# This file is part of charm-helpers.
+#
+# charm-helpers is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# charm-helpers 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 Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with charm-helpers.  If not, see <http://www.gnu.org/licenses/>.
+
+__author__ = 'Jorge Niedbalski <[e-mail]>'
+
+import os
+import subprocess
+
+
+def sed(filename, before, after, flags='g'):
+    """
+    Search and replaces the given pattern on filename.
+
+    :param filename: relative or absolute file path.
+    :param before: expression to be replaced (see 'man sed')
+    :param after: expression to replace with (see 'man sed')
+    :param flags: sed-compatible regex flags in example, to make
+    the  search and replace case insensitive, specify ``flags="i"``.
+    The ``g`` flag is always specified regardless, so you do not
+    need to remember to include it when overriding this parameter.
+    :returns: If the sed command exit code was zero then return,
+    otherwise raise CalledProcessError.
+    """
+    expression = r's/{0}/{1}/{2}'.format(before,
+                                         after, flags)
+
+    return subprocess.check_call(["sed", "-i", "-r", "-e",
+                                  expression,
+                                  os.path.expanduser(filename)])

=== modified file 'hooks/charmhelpers/core/hookenv.py'
--- hooks/charmhelpers/core/hookenv.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/core/hookenv.py	2015-08-19 13:58:57 +0000
@@ -20,11 +20,18 @@
 # Authors:
 #  Charm Helpers Developers <[e-mail]>
 
+from __future__ import print_function
+import copy
+from distutils.version import LooseVersion
+from functools import wraps
+import glob
 import os
 import json
 import yaml
 import subprocess
 import sys
+import errno
+import tempfile
 from subprocess import CalledProcessError
 
 import six
@@ -56,15 +63,18 @@
 
     will cache the result of unit_get + 'test' for future calls.
     """
+    @wraps(func)
     def wrapper(*args, **kwargs):
         global cache
         key = str((func, args, kwargs))
         try:
             return cache[key]
         except KeyError:
-            res = func(*args, **kwargs)
-            cache[key] = res
-            return res
+            pass  # Drop out of the exception handler scope.
+        res = func(*args, **kwargs)
+        cache[key] = res
+        return res
+    wrapper._wrapped = func
     return wrapper
 
 
@@ -87,7 +97,18 @@
     if not isinstance(message, six.string_types):
         message = repr(message)
     command += [message]
-    subprocess.call(command)
+    # Missing juju-log should not cause failures in unit tests
+    # Send log output to stderr
+    try:
+        subprocess.call(command)
+    except OSError as e:
+        if e.errno == errno.ENOENT:
+            if level:
+                message = "{}: {}".format(level, message)
+            message = "juju-log: {}".format(message)
+            print(message, file=sys.stderr)
+        else:
+            raise
 
 
 class Serializable(UserDict):
@@ -153,9 +174,19 @@
     return os.environ.get('JUJU_RELATION', None)
 
 
-def relation_id():
-    """The relation ID for the current relation hook"""
-    return os.environ.get('JUJU_RELATION_ID', None)
+@cached
+def relation_id(relation_name=None, service_or_unit=None):
+    """The relation ID for the current or a specified relation"""
+    if not relation_name and not service_or_unit:
+        return os.environ.get('JUJU_RELATION_ID', None)
+    elif relation_name and service_or_unit:
+        service_name = service_or_unit.split('/')[0]
+        for relid in relation_ids(relation_name):
+            remote_service = remote_service_name(relid)
+            if remote_service == service_name:
+                return relid
+    else:
+        raise ValueError('Must specify neither or both of relation_name and service_or_unit')
 
 
 def local_unit():
@@ -165,7 +196,7 @@
 
 def remote_unit():
     """The remote unit for the current relation hook"""
-    return os.environ['JUJU_REMOTE_UNIT']
+    return os.environ.get('JUJU_REMOTE_UNIT', None)
 
 
 def service_name():
@@ -173,9 +204,20 @@
     return local_unit().split('/')[0]
 
 
+@cached
+def remote_service_name(relid=None):
+    """The remote service name for a given relation-id (or the current relation)"""
+    if relid is None:
+        unit = remote_unit()
+    else:
+        units = related_units(relid)
+        unit = units[0] if units else None
+    return unit.split('/')[0] if unit else None
+
+
 def hook_name():
     """The name of the currently executing hook"""
-    return os.path.basename(sys.argv[0])
+    return os.environ.get('JUJU_HOOK_NAME', os.path.basename(sys.argv[0]))
 
 
 class Config(dict):
@@ -225,23 +267,7 @@
         self.path = os.path.join(charm_dir(), Config.CONFIG_FILE_NAME)
         if os.path.exists(self.path):
             self.load_previous()
-
-    def __getitem__(self, key):
-        """For regular dict lookups, check the current juju config first,
-        then the previous (saved) copy. This ensures that user-saved values
-        will be returned by a dict lookup.
-
-        """
-        try:
-            return dict.__getitem__(self, key)
-        except KeyError:
-            return (self._prev_dict or {})[key]
-
-    def keys(self):
-        prev_keys = []
-        if self._prev_dict is not None:
-            prev_keys = self._prev_dict.keys()
-        return list(set(prev_keys + list(dict.keys(self))))
+        atexit(self._implicit_save)
 
     def load_previous(self, path=None):
         """Load previous copy of config from disk.
@@ -260,6 +286,9 @@
         self.path = path or self.path
         with open(self.path) as f:
             self._prev_dict = json.load(f)
+        for k, v in copy.deepcopy(self._prev_dict).items():
+            if k not in self:
+                self[k] = v
 
     def changed(self, key):
         """Return True if the current value for this key is different from
@@ -291,13 +320,13 @@
         instance.
 
         """
-        if self._prev_dict:
-            for k, v in six.iteritems(self._prev_dict):
-                if k not in self:
-                    self[k] = v
         with open(self.path, 'w') as f:
             json.dump(self, f)
 
+    def _implicit_save(self):
+        if self.implicit_save:
+            self.save()
+
 
 @cached
 def config(scope=None):
@@ -340,18 +369,49 @@
     """Set relation information for the current unit"""
     relation_settings = relation_settings if relation_settings else {}
     relation_cmd_line = ['relation-set']
+    accepts_file = "--file" in subprocess.check_output(
+        relation_cmd_line + ["--help"], universal_newlines=True)
     if relation_id is not None:
         relation_cmd_line.extend(('-r', relation_id))
-    for k, v in (list(relation_settings.items()) + list(kwargs.items())):
-        if v is None:
-            relation_cmd_line.append('{}='.format(k))
-        else:
-            relation_cmd_line.append('{}={}'.format(k, v))
-    subprocess.check_call(relation_cmd_line)
+    settings = relation_settings.copy()
+    settings.update(kwargs)
+    for key, value in settings.items():
+        # Force value to be a string: it always should, but some call
+        # sites pass in things like dicts or numbers.
+        if value is not None:
+            settings[key] = "{}".format(value)
+    if accepts_file:
+        # --file was introduced in Juju 1.23.2. Use it by default if
+        # available, since otherwise we'll break if the relation data is
+        # too big. Ideally we should tell relation-set to read the data from
+        # stdin, but that feature is broken in 1.23.2: Bug #1454678.
+        with tempfile.NamedTemporaryFile(delete=False) as settings_file:
+            settings_file.write(yaml.safe_dump(settings).encode("utf-8"))
+        subprocess.check_call(
+            relation_cmd_line + ["--file", settings_file.name])
+        os.remove(settings_file.name)
+    else:
+        for key, value in settings.items():
+            if value is None:
+                relation_cmd_line.append('{}='.format(key))
+            else:
+                relation_cmd_line.append('{}={}'.format(key, value))
+        subprocess.check_call(relation_cmd_line)
     # Flush cache of any relation-gets for local unit
     flush(local_unit())
 
 
+def relation_clear(r_id=None):
+    ''' Clears any relation data already set on relation r_id '''
+    settings = relation_get(rid=r_id,
+                            unit=local_unit())
+    for setting in settings:
+        if setting not in ['public-address', 'private-address']:
+            settings[setting] = None
+    relation_set(relation_id=r_id,
+                 **settings)
+
+
 @cached
 def relation_ids(reltype=None):
     """A list of relation_ids"""
@@ -431,6 +491,63 @@
 
 
 @cached
+def relation_to_interface(relation_name):
+    """
+    Given the name of a relation, return the interface that relation uses.
+
+    :returns: The interface name, or ``None``.
+    """
+    return relation_to_role_and_interface(relation_name)[1]
+
+
+@cached
+def relation_to_role_and_interface(relation_name):
+    """
+    Given the name of a relation, return the role and the name of the interface
+    that relation uses (where role is one of ``provides``, ``requires``, or ``peer``).
+
+    :returns: A tuple containing ``(role, interface)``, or ``(None, None)``.
+    """
+    _metadata = metadata()
+    for role in ('provides', 'requires', 'peer'):
+        interface = _metadata.get(role, {}).get(relation_name, {}).get('interface')
+        if interface:
+            return role, interface
+    return None, None
+
+
+@cached
+def role_and_interface_to_relations(role, interface_name):
+    """
+    Given a role and interface name, return a list of relation names for the
+    current charm that use that interface under that role (where role is one
+    of ``provides``, ``requires``, or ``peer``).
+
+    :returns: A list of relation names.
+    """
+    _metadata = metadata()
+    results = []
+    for relation_name, relation in _metadata.get(role, {}).items():
+        if relation['interface'] == interface_name:
+            results.append(relation_name)
+    return results
+
+
+@cached
+def interface_to_relations(interface_name):
+    """
+    Given an interface, return a list of relation names for the current
+    charm that use that interface.
+
+    :returns: A list of relation names.
+    """
+    results = []
+    for role in ('provides', 'requires', 'peer'):
+        results.extend(role_and_interface_to_relations(role, interface_name))
+    return results
+
+
+@cached
 def charm_name():
     """Get the name of the current charm as is specified on metadata.yaml"""
     return metadata().get('name')
@@ -496,6 +613,11 @@
         return None
 
 
+def unit_public_ip():
+    """Get this unit's public IP address"""
+    return unit_get('public-address')
+
+
 def unit_private_ip():
     """Get this unit's private IP address"""
     return unit_get('private-address')
@@ -528,10 +650,14 @@
             hooks.execute(sys.argv)
     """
 
-    def __init__(self, config_save=True):
+    def __init__(self, config_save=None):
         super(Hooks, self).__init__()
         self._hooks = {}
-        self._config_save = config_save
+
+        # For unknown reasons, we allow the Hooks constructor to override
+        # config().implicit_save.
+        if config_save is not None:
+            config().implicit_save = config_save
 
     def register(self, name, function):
         """Register a hook"""
@@ -539,13 +665,16 @@
 
     def execute(self, args):
         """Execute a registered hook based on args[0]"""
+        _run_atstart()
         hook_name = os.path.basename(args[0])
         if hook_name in self._hooks:
-            self._hooks[hook_name]()
-            if self._config_save:
-                cfg = config()
-                if cfg.implicit_save:
-                    cfg.save()
+            try:
+                self._hooks[hook_name]()
+            except SystemExit as x:
+                if x.code is None or x.code == 0:
+                    _run_atexit()
+                raise
+            _run_atexit()
         else:
             raise UnregisteredHookError(hook_name)
 
@@ -566,3 +695,202 @@
 def charm_dir():
     """Return the root directory of the current charm"""
     return os.environ.get('CHARM_DIR')
+
+
+@cached
+def action_get(key=None):
+    """Gets the value of an action parameter, or all key/value param pairs"""
+    cmd = ['action-get']
+    if key is not None:
+        cmd.append(key)
+    cmd.append('--format=json')
+    action_data = json.loads(subprocess.check_output(cmd).decode('UTF-8'))
+    return action_data
+
+
+def action_set(values):
+    """Sets the values to be returned after the action finishes"""
+    cmd = ['action-set']
+    for k, v in list(values.items()):
+        cmd.append('{}={}'.format(k, v))
+    subprocess.check_call(cmd)
+
+
+def action_fail(message):
+    """Sets the action status to failed and sets the error message.
+
+    The results set by action_set are preserved."""
+    subprocess.check_call(['action-fail', message])
+
+
+def action_name():
+    """Get the name of the currently executing action."""
+    return os.environ.get('JUJU_ACTION_NAME')
+
+
+def action_uuid():
+    """Get the UUID of the currently executing action."""
+    return os.environ.get('JUJU_ACTION_UUID')
+
+
+def action_tag():
+    """Get the tag for the currently executing action."""
+    return os.environ.get('JUJU_ACTION_TAG')
+
+
+def status_set(workload_state, message):
+    """Set the workload state with a message
+
+    Use status-set to set the workload state with a message which is visible
+    to the user via juju status. If the status-set command is not found then
+    assume this is juju < 1.23 and juju-log the message unstead.
+
+    workload_state -- valid juju workload state.
+    message        -- status update message
+    """
+    valid_states = ['maintenance', 'blocked', 'waiting', 'active']
+    if workload_state not in valid_states:
+        raise ValueError(
+            '{!r} is not a valid workload state'.format(workload_state)
+        )
+    cmd = ['status-set', workload_state, message]
+    try:
+        ret = subprocess.call(cmd)
+        if ret == 0:
+            return
+    except OSError as e:
+        if e.errno != errno.ENOENT:
+            raise
+    log_message = 'status-set failed: {} {}'.format(workload_state,
+                                                    message)
+    log(log_message, level='INFO')
+
+
+def status_get():
+    """Retrieve the previously set juju workload state
+
+    If the status-set command is not found then assume this is juju < 1.23 and
+    return 'unknown'
+    """
+    cmd = ['status-get']
+    try:
+        raw_status = subprocess.check_output(cmd, universal_newlines=True)
+        status = raw_status.rstrip()
+        return status
+    except OSError as e:
+        if e.errno == errno.ENOENT:
+            return 'unknown'
+        else:
+            raise
+
+
+def translate_exc(from_exc, to_exc):
+    def inner_translate_exc1(f):
+        def inner_translate_exc2(*args, **kwargs):
+            try:
+                return f(*args, **kwargs)
+            except from_exc:
+                raise to_exc
+
+        return inner_translate_exc2
+
+    return inner_translate_exc1
+
+
+@translate_exc(from_exc=OSError, to_exc=NotImplementedError)
+def is_leader():
+    """Does the current unit hold the juju leadership
+
+    Uses juju to determine whether the current unit is the leader of its peers
+    """
+    cmd = ['is-leader', '--format=json']
+    return json.loads(subprocess.check_output(cmd).decode('UTF-8'))
+
+
+@translate_exc(from_exc=OSError, to_exc=NotImplementedError)
+def leader_get(attribute=None):
+    """Juju leader get value(s)"""
+    cmd = ['leader-get', '--format=json'] + [attribute or '-']
+    return json.loads(subprocess.check_output(cmd).decode('UTF-8'))
+
+
+@translate_exc(from_exc=OSError, to_exc=NotImplementedError)
+def leader_set(settings=None, **kwargs):
+    """Juju leader set value(s)"""
+    # Don't log secrets.
+    # log("Juju leader-set '%s'" % (settings), level=DEBUG)
+    cmd = ['leader-set']
+    settings = settings or {}
+    settings.update(kwargs)
+    for k, v in settings.items():
+        if v is None:
+            cmd.append('{}='.format(k))
+        else:
+            cmd.append('{}={}'.format(k, v))
+    subprocess.check_call(cmd)
+
+
+@cached
+def juju_version():
+    """Full version string (eg. '1.23.3.1-trusty-amd64')"""
+    # Per https://bugs.launchpad.net/juju-core/+bug/1455368/comments/1
+    jujud = glob.glob('/var/lib/juju/tools/machine-*/jujud')[0]
+    return subprocess.check_output([jujud, 'version'],
+                                   universal_newlines=True).strip()
+
+
+@cached
+def has_juju_version(minimum_version):
+    """Return True if the Juju version is at least the provided version"""
+    return LooseVersion(juju_version()) >= LooseVersion(minimum_version)
+
+
+_atexit = []
+_atstart = []
+
+
+def atstart(callback, *args, **kwargs):
+    '''Schedule a callback to run before the main hook.
+
+    Callbacks are run in the order they were added.
+
+    This is useful for modules and classes to perform initialization
+    and inject behavior. In particular:
+
+        - Run common code before all of your hooks, such as logging
+          the hook name or interesting relation data.
+        - Defer object or module initialization that requires a hook
+          context until we know there actually is a hook context,
+          making testing easier.
+        - Rather than requiring charm authors to include boilerplate to
+          invoke your helper's behavior, have it run automatically if
+          your object is instantiated or module imported.
+
+    This is not at all useful after your hook framework as been launched.
+    '''
+    global _atstart
+    _atstart.append((callback, args, kwargs))
+
+
+def atexit(callback, *args, **kwargs):
+    '''Schedule a callback to run on successful hook completion.
+
+    Callbacks are run in the reverse order that they were added.'''
+    _atexit.append((callback, args, kwargs))
+
+
+def _run_atstart():
+    '''Hook frameworks must invoke this before running the main hook body.'''
+    global _atstart
+    for callback, args, kwargs in _atstart:
+        callback(*args, **kwargs)
+    del _atstart[:]
+
+
+def _run_atexit():
+    '''Hook frameworks must invoke this after the main hook body has
+    successfully completed. Do not invoke it if the hook fails.'''
+    global _atexit
+    for callback, args, kwargs in reversed(_atexit):
+        callback(*args, **kwargs)
+    del _atexit[:]

=== modified file 'hooks/charmhelpers/core/host.py'
--- hooks/charmhelpers/core/host.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/core/host.py	2015-08-19 13:58:57 +0000
@@ -24,6 +24,7 @@
 import os
 import re
 import pwd
+import glob
 import grp
 import random
 import string
@@ -62,6 +63,36 @@
     return service_result
 
 
+def service_pause(service_name, init_dir=None):
+    """Pause a system service.
+
+    Stop it, and prevent it from starting again at boot."""
+    if init_dir is None:
+        init_dir = "/etc/init"
+    stopped = service_stop(service_name)
+    # XXX: Support systemd too
+    override_path = os.path.join(
+        init_dir, '{}.override'.format(service_name))
+    with open(override_path, 'w') as fh:
+        fh.write("manual\n")
+    return stopped
+
+
+def service_resume(service_name, init_dir=None):
+    """Resume a system service.
+
+    Reenable starting again at boot. Start the service"""
+    # XXX: Support systemd too
+    if init_dir is None:
+        init_dir = "/etc/init"
+    override_path = os.path.join(
+        init_dir, '{}.override'.format(service_name))
+    if os.path.exists(override_path):
+        os.unlink(override_path)
+    started = service_start(service_name)
+    return started
+
+
 def service(action, service_name):
     """Control a system service"""
     cmd = ['service', service_name, action]
@@ -90,7 +121,7 @@
             ['service', service_name, 'status'],
             stderr=subprocess.STDOUT).decode('UTF-8')
     except subprocess.CalledProcessError as e:
-        return 'unrecognized service' not in e.output
+        return b'unrecognized service' not in e.output
     else:
         return True
 
@@ -117,6 +148,16 @@
     return user_info
 
 
+def user_exists(username):
+    """Check if a user exists"""
+    try:
+        pwd.getpwnam(username)
+        user_exists = True
+    except KeyError:
+        user_exists = False
+    return user_exists
+
+
 def add_group(group_name, system_group=False):
     """Add a group to the system"""
     try:
@@ -139,11 +180,7 @@
 
 def add_user_to_group(username, group):
     """Add a user to a group"""
-    cmd = [
-        'gpasswd', '-a',
-        username,
-        group
-    ]
+    cmd = ['gpasswd', '-a', username, group]
     log("Adding user {} to group {}".format(username, group))
     subprocess.check_call(cmd)
 
@@ -253,6 +290,17 @@
     return system_mounts
 
 
+def fstab_mount(mountpoint):
+    """Mount filesystem using fstab"""
+    cmd_args = ['mount', mountpoint]
+    try:
+        subprocess.check_output(cmd_args)
+    except subprocess.CalledProcessError as e:
+        log('Error unmounting {}\n{}'.format(mountpoint, e.output))
+        return False
+    return True
+
+
 def file_hash(path, hash_type='md5'):
     """
     Generate a hash checksum of the contents of 'path' or None if not found.
@@ -269,6 +317,21 @@
         return None
 
 
+def path_hash(path):
+    """
+    Generate a hash checksum of all files matching 'path'. Standard wildcards
+    like '*' and '?' are supported, see documentation for the 'glob' module for
+    more information.
+
+    :return: dict: A { filename: hash } dictionary for all matched files.
+                   Empty if none found.
+    """
+    return {
+        filename: file_hash(filename)
+        for filename in glob.iglob(path)
+    }
+
+
 def check_hash(path, checksum, hash_type='md5'):
     """
     Validate a file using a cryptographic checksum.
@@ -296,23 +359,25 @@
 
         @restart_on_change({
             '/etc/ceph/ceph.conf': [ 'cinder-api', 'cinder-volume' ]
+            '/etc/apache/sites-enabled/*': [ 'apache2' ]
             })
-        def ceph_client_changed():
+        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.
+    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):
-            checksums = {}
-            for path in restart_map:
-                checksums[path] = file_hash(path)
+            checksums = {path: path_hash(path) for path in restart_map}
             f(*args, **kwargs)
             restarts = []
             for path in restart_map:
-                if checksums[path] != file_hash(path):
+                if path_hash(path) != checksums[path]:
                     restarts += restart_map[path]
             services_list = list(OrderedDict.fromkeys(restarts))
             if not stopstart:
@@ -339,34 +404,93 @@
 def pwgen(length=None):
     """Generate a random pasword."""
     if length is None:
+        # A random length is ok to use a weak PRNG
         length = random.choice(range(35, 45))
     alphanumeric_chars = [
         l for l in (string.ascii_letters + string.digits)
         if l not in 'l0QD1vAEIOUaeiou']
+    # Use a crypto-friendly PRNG (e.g. /dev/urandom) for making the
+    # actual password
+    random_generator = random.SystemRandom()
     random_chars = [
-        random.choice(alphanumeric_chars) for _ in range(length)]
+        random_generator.choice(alphanumeric_chars) for _ in range(length)]
     return(''.join(random_chars))
 
 
-def list_nics(nic_type):
+def is_phy_iface(interface):
+    """Returns True if interface is not virtual, otherwise False."""
+    if interface:
+        sys_net = '/sys/class/net'
+        if os.path.isdir(sys_net):
+            for iface in glob.glob(os.path.join(sys_net, '*')):
+                if '/virtual/' in os.path.realpath(iface):
+                    continue
+
+                if interface == os.path.basename(iface):
+                    return True
+
+    return False
+
+
+def get_bond_master(interface):
+    """Returns bond master if interface is bond slave otherwise None.
+
+    NOTE: the provided interface is expected to be physical
+    """
+    if interface:
+        iface_path = '/sys/class/net/%s' % (interface)
+        if os.path.exists(iface_path):
+            if '/virtual/' in os.path.realpath(iface_path):
+                return None
+
+            master = os.path.join(iface_path, 'master')
+            if os.path.exists(master):
+                master = os.path.realpath(master)
+                # make sure it is a bond master
+                if os.path.exists(os.path.join(master, 'bonding')):
+                    return os.path.basename(master)
+
+    return None
+
+
+def list_nics(nic_type=None):
     '''Return a list of nics of given type(s)'''
     if isinstance(nic_type, six.string_types):
         int_types = [nic_type]
     else:
         int_types = nic_type
+
     interfaces = []
-    for int_type in int_types:
-        cmd = ['ip', 'addr', 'show', 'label', int_type + '*']
+    if nic_type:
+        for int_type in int_types:
+            cmd = ['ip', 'addr', 'show', 'label', int_type + '*']
+            ip_output = subprocess.check_output(cmd).decode('UTF-8')
+            ip_output = ip_output.split('\n')
+            ip_output = (line for line in ip_output if line)
+            for line in ip_output:
+                if line.split()[1].startswith(int_type):
+                    matched = re.search('.*: (' + int_type +
+                                        r'[0-9]+\.[0-9]+)@.*', line)
+                    if matched:
+                        iface = matched.groups()[0]
+                    else:
+                        iface = line.split()[1].replace(":", "")
+
+                    if iface not in interfaces:
+                        interfaces.append(iface)
+    else:
+        cmd = ['ip', 'a']
         ip_output = subprocess.check_output(cmd).decode('UTF-8').split('\n')
-        ip_output = (line for line in ip_output if line)
+        ip_output = (line.strip() for line in ip_output if line)
+
+        key = re.compile('^[0-9]+:\s+(.+):')
         for line in ip_output:
-            if line.split()[1].startswith(int_type):
-                matched = re.search('.*: (' + int_type + r'[0-9]+\.[0-9]+)@.*', line)
-                if matched:
-                    interface = matched.groups()[0]
-                else:
-                    interface = line.split()[1].replace(":", "")
-                interfaces.append(interface)
+            matched = re.search(key, line)
+            if matched:
+                iface = matched.group(1)
+                iface = iface.partition("@")[0]
+                if iface not in interfaces:
+                    interfaces.append(iface)
 
     return interfaces
 

=== added file 'hooks/charmhelpers/core/hugepage.py'
--- hooks/charmhelpers/core/hugepage.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/hugepage.py	2015-08-19 13:58:57 +0000
@@ -0,0 +1,62 @@
+# -*- coding: utf-8 -*-
+
+# Copyright 2014-2015 Canonical Limited.
+#
+# This file is part of charm-helpers.
+#
+# charm-helpers is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# charm-helpers 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 Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with charm-helpers.  If not, see <http://www.gnu.org/licenses/>.
+
+import yaml
+from charmhelpers.core import fstab
+from charmhelpers.core import sysctl
+from charmhelpers.core.host import (
+    add_group,
+    add_user_to_group,
+    fstab_mount,
+    mkdir,
+)
+
+
+def hugepage_support(user, group='hugetlb', nr_hugepages=256,
+                     max_map_count=65536, mnt_point='/run/hugepages/kvm',
+                     pagesize='2MB', mount=True):
+    """Enable hugepages on system.
+
+    Args:
+    user (str)  -- Username to allow access to hugepages to
+    group (str) -- Group name to own hugepages
+    nr_hugepages (int) -- Number of pages to reserve
+    max_map_count (int) -- Number of Virtual Memory Areas a process can own
+    mnt_point (str) -- Directory to mount hugepages on
+    pagesize (str) -- Size of hugepages
+    mount (bool) -- Whether to Mount hugepages
+    """
+    group_info = add_group(group)
+    gid = group_info.gr_gid
+    add_user_to_group(user, group)
+    sysctl_settings = {
+        'vm.nr_hugepages': nr_hugepages,
+        'vm.max_map_count': max_map_count,
+        'vm.hugetlb_shm_group': gid,
+    }
+    sysctl.create(yaml.dump(sysctl_settings), '/etc/sysctl.d/10-hugepage.conf')
+    mkdir(mnt_point, owner='root', group='root', perms=0o755, force=False)
+    lfstab = fstab.Fstab()
+    fstab_entry = lfstab.get_entry_by_attr('mountpoint', mnt_point)
+    if fstab_entry:
+        lfstab.remove_entry(fstab_entry)
+    entry = lfstab.Entry('nodev', mnt_point, 'hugetlbfs',
+                         'mode=1770,gid={},pagesize={}'.format(gid, pagesize), 0, 0)
+    lfstab.add_entry(entry)
+    if mount:
+        fstab_mount(mnt_point)

=== modified file 'hooks/charmhelpers/core/services/base.py'
--- hooks/charmhelpers/core/services/base.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/core/services/base.py	2015-08-19 13:58:57 +0000
@@ -15,9 +15,9 @@
 # along with charm-helpers.  If not, see <http://www.gnu.org/licenses/>.
 
 import os
-import re
 import json
-from collections import Iterable
+from inspect import getargspec
+from collections import Iterable, OrderedDict
 
 from charmhelpers.core import host
 from charmhelpers.core import hookenv
@@ -119,7 +119,7 @@
         """
         self._ready_file = os.path.join(hookenv.charm_dir(), 'READY-SERVICES.json')
         self._ready = None
-        self.services = {}
+        self.services = OrderedDict()
         for service in services or []:
             service_name = service['service']
             self.services[service_name] = service
@@ -128,15 +128,18 @@
         """
         Handle the current hook by doing The Right Thing with the registered services.
         """
-        hook_name = hookenv.hook_name()
-        if hook_name == 'stop':
-            self.stop_services()
-        else:
-            self.provide_data()
-            self.reconfigure_services()
-        cfg = hookenv.config()
-        if cfg.implicit_save:
-            cfg.save()
+        hookenv._run_atstart()
+        try:
+            hook_name = hookenv.hook_name()
+            if hook_name == 'stop':
+                self.stop_services()
+            else:
+                self.reconfigure_services()
+                self.provide_data()
+        except SystemExit as x:
+            if x.code is None or x.code == 0:
+                hookenv._run_atexit()
+        hookenv._run_atexit()
 
     def provide_data(self):
         """
@@ -145,15 +148,36 @@
         A provider must have a `name` attribute, which indicates which relation
         to set data on, and a `provide_data()` method, which returns a dict of
         data to set.
+
+        The `provide_data()` method can optionally accept two parameters:
+
+          * ``remote_service`` The name of the remote service that the data will
+            be provided to.  The `provide_data()` method will be called once
+            for each connected service (not unit).  This allows the method to
+            tailor its data to the given service.
+          * ``service_ready`` Whether or not the service definition had all of
+            its requirements met, and thus the ``data_ready`` callbacks run.
+
+        Note that the ``provided_data`` methods are now called **after** the
+        ``data_ready`` callbacks are run.  This gives the ``data_ready`` callbacks
+        a chance to generate any data necessary for the providing to the remote
+        services.
         """
-        hook_name = hookenv.hook_name()
-        for service in self.services.values():
+        for service_name, service in self.services.items():
+            service_ready = self.is_ready(service_name)
             for provider in service.get('provided_data', []):
-                if re.match(r'{}-relation-(joined|changed)'.format(provider.name), hook_name):
-                    data = provider.provide_data()
-                    _ready = provider._is_ready(data) if hasattr(provider, '_is_ready') else data
-                    if _ready:
-                        hookenv.relation_set(None, data)
+                for relid in hookenv.relation_ids(provider.name):
+                    units = hookenv.related_units(relid)
+                    if not units:
+                        continue
+                    remote_service = units[0].split('/')[0]
+                    argspec = getargspec(provider.provide_data)
+                    if len(argspec.args) > 1:
+                        data = provider.provide_data(remote_service, service_ready)
+                    else:
+                        data = provider.provide_data()
+                    if data:
+                        hookenv.relation_set(relid, data)
 
     def reconfigure_services(self, *service_names):
         """

=== modified file 'hooks/charmhelpers/core/services/helpers.py'
--- hooks/charmhelpers/core/services/helpers.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/core/services/helpers.py	2015-08-19 13:58:57 +0000
@@ -16,7 +16,9 @@
 
 import os
 import yaml
+
 from charmhelpers.core import hookenv
+from charmhelpers.core import host
 from charmhelpers.core import templating
 
 from charmhelpers.core.services.base import ManagerCallback
@@ -45,12 +47,14 @@
     """
     name = None
     interface = None
-    required_keys = []
 
     def __init__(self, name=None, additional_required_keys=None):
+        if not hasattr(self, 'required_keys'):
+            self.required_keys = []
+
         if name is not None:
             self.name = name
-        if additional_required_keys is not None:
+        if additional_required_keys:
             self.required_keys.extend(additional_required_keys)
         self.get_data()
 
@@ -134,7 +138,10 @@
     """
     name = 'db'
     interface = 'mysql'
-    required_keys = ['host', 'user', 'password', 'database']
+
+    def __init__(self, *args, **kwargs):
+        self.required_keys = ['host', 'user', 'password', 'database']
+        RelationContext.__init__(self, *args, **kwargs)
 
 
 class HttpRelation(RelationContext):
@@ -146,7 +153,10 @@
     """
     name = 'website'
     interface = 'http'
-    required_keys = ['host', 'port']
+
+    def __init__(self, *args, **kwargs):
+        self.required_keys = ['host', 'port']
+        RelationContext.__init__(self, *args, **kwargs)
 
     def provide_data(self):
         return {
@@ -231,28 +241,42 @@
     action.
 
     :param str source: The template source file, relative to
-    `$CHARM_DIR/templates`
+        `$CHARM_DIR/templates`
 
     :param str target: The target to write the rendered template to
     :param str owner: The owner of the rendered file
     :param str group: The group of the rendered file
     :param int perms: The permissions of the rendered file
+    :param partial on_change_action: functools partial to be executed when
+                                     rendered file changes
     """
     def __init__(self, source, target,
-                 owner='root', group='root', perms=0o444):
+                 owner='root', group='root', perms=0o444,
+                 on_change_action=None):
         self.source = source
         self.target = target
         self.owner = owner
         self.group = group
         self.perms = perms
+        self.on_change_action = on_change_action
 
     def __call__(self, manager, service_name, event_name):
+        pre_checksum = ''
+        if self.on_change_action and os.path.isfile(self.target):
+            pre_checksum = host.file_hash(self.target)
         service = manager.get_service(service_name)
         context = {}
         for ctx in service.get('required_data', []):
             context.update(ctx)
         templating.render(self.source, self.target, context,
                           self.owner, self.group, self.perms)
+        if self.on_change_action:
+            if pre_checksum == host.file_hash(self.target):
+                hookenv.log(
+                    'No change detected: {}'.format(self.target),
+                    hookenv.DEBUG)
+            else:
+                self.on_change_action()
 
 
 # Convenience aliases for templates

=== modified file 'hooks/charmhelpers/core/strutils.py'
--- hooks/charmhelpers/core/strutils.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/core/strutils.py	2015-08-19 13:58:57 +0000
@@ -33,9 +33,9 @@
 
     value = value.strip().lower()
 
-    if value in ['y', 'yes', 'true', 't']:
+    if value in ['y', 'yes', 'true', 't', 'on']:
         return True
-    elif value in ['n', 'no', 'false', 'f']:
+    elif value in ['n', 'no', 'false', 'f', 'off']:
         return False
 
     msg = "Unable to interpret string value '%s' as boolean" % (value)

=== modified file 'hooks/charmhelpers/core/unitdata.py'
--- hooks/charmhelpers/core/unitdata.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/core/unitdata.py	2015-08-19 13:58:57 +0000
@@ -152,6 +152,7 @@
 import collections
 import contextlib
 import datetime
+import itertools
 import json
 import os
 import pprint
@@ -164,8 +165,7 @@
 class Storage(object):
     """Simple key value database for local unit state within charms.
 
-    Modifications are automatically committed at hook exit. That's
-    currently regardless of exit code.
+    Modifications are not persisted unless :meth:`flush` is called.
 
     To support dicts, lists, integer, floats, and booleans values
     are automatically json encoded/decoded.
@@ -173,8 +173,11 @@
     def __init__(self, path=None):
         self.db_path = path
         if path is None:
-            self.db_path = os.path.join(
-                os.environ.get('CHARM_DIR', ''), '.unit-state.db')
+            if 'UNIT_STATE_DB' in os.environ:
+                self.db_path = os.environ['UNIT_STATE_DB']
+            else:
+                self.db_path = os.path.join(
+                    os.environ.get('CHARM_DIR', ''), '.unit-state.db')
         self.conn = sqlite3.connect('%s' % self.db_path)
         self.cursor = self.conn.cursor()
         self.revision = None
@@ -189,15 +192,8 @@
         self.conn.close()
         self._closed = True
 
-    def _scoped_query(self, stmt, params=None):
-        if params is None:
-            params = []
-        return stmt, params
-
     def get(self, key, default=None, record=False):
-        self.cursor.execute(
-            *self._scoped_query(
-                'select data from kv where key=?', [key]))
+        self.cursor.execute('select data from kv where key=?', [key])
         result = self.cursor.fetchone()
         if not result:
             return default
@@ -206,33 +202,81 @@
         return json.loads(result[0])
 
     def getrange(self, key_prefix, strip=False):
-        stmt = "select key, data from kv where key like '%s%%'" % key_prefix
-        self.cursor.execute(*self._scoped_query(stmt))
+        """
+        Get a range of keys starting with a common prefix as a mapping of
+        keys to values.
+
+        :param str key_prefix: Common prefix among all keys
+        :param bool strip: Optionally strip the common prefix from the key
+            names in the returned dict
+        :return dict: A (possibly empty) dict of key-value mappings
+        """
+        self.cursor.execute("select key, data from kv where key like ?",
+                            ['%s%%' % key_prefix])
         result = self.cursor.fetchall()
 
         if not result:
-            return None
+            return {}
         if not strip:
             key_prefix = ''
         return dict([
             (k[len(key_prefix):], json.loads(v)) for k, v in result])
 
     def update(self, mapping, prefix=""):
+        """
+        Set the values of multiple keys at once.
+
+        :param dict mapping: Mapping of keys to values
+        :param str prefix: Optional prefix to apply to all keys in `mapping`
+            before setting
+        """
         for k, v in mapping.items():
             self.set("%s%s" % (prefix, k), v)
 
     def unset(self, key):
+        """
+        Remove a key from the database entirely.
+        """
         self.cursor.execute('delete from kv where key=?', [key])
         if self.revision and self.cursor.rowcount:
             self.cursor.execute(
                 'insert into kv_revisions values (?, ?, ?)',
                 [key, self.revision, json.dumps('DELETED')])
 
+    def unsetrange(self, keys=None, prefix=""):
+        """
+        Remove a range of keys starting with a common prefix, from the database
+        entirely.
+
+        :param list keys: List of keys to remove.
+        :param str prefix: Optional prefix to apply to all keys in ``keys``
+            before removing.
+        """
+        if keys is not None:
+            keys = ['%s%s' % (prefix, key) for key in keys]
+            self.cursor.execute('delete from kv where key in (%s)' % ','.join(['?'] * len(keys)), keys)
+            if self.revision and self.cursor.rowcount:
+                self.cursor.execute(
+                    'insert into kv_revisions values %s' % ','.join(['(?, ?, ?)'] * len(keys)),
+                    list(itertools.chain.from_iterable((key, self.revision, json.dumps('DELETED')) for key in keys)))
+        else:
+            self.cursor.execute('delete from kv where key like ?',
+                                ['%s%%' % prefix])
+            if self.revision and self.cursor.rowcount:
+                self.cursor.execute(
+                    'insert into kv_revisions values (?, ?, ?)',
+                    ['%s%%' % prefix, self.revision, json.dumps('DELETED')])
+
     def set(self, key, value):
+        """
+        Set a value in the database.
+
+        :param str key: Key to set the value for
+        :param value: Any JSON-serializable value to be set
+        """
         serialized = json.dumps(value)
 
-        self.cursor.execute(
-            'select data from kv where key=?', [key])
+        self.cursor.execute('select data from kv where key=?', [key])
         exists = self.cursor.fetchone()
 
         # Skip mutations to the same value
@@ -443,7 +487,7 @@
         data = hookenv.execution_environment()
         self.conf = conf_delta = self.kv.delta(data['conf'], 'config')
         self.rels = rels_delta = self.kv.delta(data['rels'], 'rels')
-        self.kv.set('env', data['env'])
+        self.kv.set('env', dict(data['env']))
         self.kv.set('unit', data['unit'])
         self.kv.set('relid', data.get('relid'))
         return conf_delta, rels_delta

=== modified file 'hooks/charmhelpers/fetch/__init__.py'
--- hooks/charmhelpers/fetch/__init__.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/fetch/__init__.py	2015-08-19 13:58:57 +0000
@@ -90,6 +90,14 @@
     'kilo/proposed': 'trusty-proposed/kilo',
     'trusty-kilo/proposed': 'trusty-proposed/kilo',
     'trusty-proposed/kilo': 'trusty-proposed/kilo',
+    # Liberty
+    'liberty': 'trusty-updates/liberty',
+    'trusty-liberty': 'trusty-updates/liberty',
+    'trusty-liberty/updates': 'trusty-updates/liberty',
+    'trusty-updates/liberty': 'trusty-updates/liberty',
+    'liberty/proposed': 'trusty-proposed/liberty',
+    'trusty-liberty/proposed': 'trusty-proposed/liberty',
+    'trusty-proposed/liberty': 'trusty-proposed/liberty',
 }
 
 # The order of this list is very important. Handlers should be listed in from
@@ -158,7 +166,7 @@
 
 def apt_cache(in_memory=True):
     """Build and return an apt cache"""
-    import apt_pkg
+    from apt import apt_pkg
     apt_pkg.init()
     if in_memory:
         apt_pkg.config.set("Dir::Cache::pkgcache", "")
@@ -215,19 +223,27 @@
     _run_apt_command(cmd, fatal)
 
 
+def apt_mark(packages, mark, fatal=False):
+    """Flag one or more packages using apt-mark"""
+    cmd = ['apt-mark', mark]
+    if isinstance(packages, six.string_types):
+        cmd.append(packages)
+    else:
+        cmd.extend(packages)
+    log("Holding {}".format(packages))
+
+    if fatal:
+        subprocess.check_call(cmd, universal_newlines=True)
+    else:
+        subprocess.call(cmd, universal_newlines=True)
+
+
 def apt_hold(packages, fatal=False):
-    """Hold one or more packages"""
-    cmd = ['apt-mark', 'hold']
-    if isinstance(packages, six.string_types):
-        cmd.append(packages)
-    else:
-        cmd.extend(packages)
-    log("Holding {}".format(packages))
-
-    if fatal:
-        subprocess.check_call(cmd)
-    else:
-        subprocess.call(cmd)
+    return apt_mark(packages, 'hold', fatal=fatal)
+
+
+def apt_unhold(packages, fatal=False):
+    return apt_mark(packages, 'unhold', fatal=fatal)
 
 
 def add_source(source, key=None):
@@ -370,8 +386,9 @@
     for handler in handlers:
         try:
             installed_to = handler.install(source, *args, **kwargs)
-        except UnhandledSource:
-            pass
+        except UnhandledSource as e:
+            log('Install source attempt unsuccessful: {}'.format(e),
+                level='WARNING')
     if not installed_to:
         raise UnhandledSource("No handler found for source {}".format(source))
     return installed_to

=== modified file 'hooks/charmhelpers/fetch/archiveurl.py'
--- hooks/charmhelpers/fetch/archiveurl.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/fetch/archiveurl.py	2015-08-19 13:58:57 +0000
@@ -77,6 +77,8 @@
     def can_handle(self, source):
         url_parts = self.parse_url(source)
         if url_parts.scheme not in ('http', 'https', 'ftp', 'file'):
+            # XXX: Why is this returning a boolean and a string? It's
+            # doomed to fail since "bool(can_handle('foo://'))"  will be True.
             return "Wrong source type"
         if get_archive_handler(self.base_url(source)):
             return True
@@ -155,7 +157,11 @@
             else:
                 algorithms = hashlib.algorithms_available
             if key in algorithms:
-                check_hash(dld_file, value, key)
+                if len(value) != 1:
+                    raise TypeError(
+                        "Expected 1 hash value, not %d" % len(value))
+                expected = value[0]
+                check_hash(dld_file, expected, key)
         if checksum:
             check_hash(dld_file, checksum, hash_type)
         return extract(dld_file, dest)

=== modified file 'hooks/charmhelpers/fetch/giturl.py'
--- hooks/charmhelpers/fetch/giturl.py	2015-02-25 00:24:56 +0000
+++ hooks/charmhelpers/fetch/giturl.py	2015-08-19 13:58:57 +0000
@@ -45,14 +45,16 @@
         else:
             return True
 
-    def clone(self, source, dest, branch):
+    def clone(self, source, dest, branch, depth=None):
         if not self.can_handle(source):
             raise UnhandledSource("Cannot handle {}".format(source))
 
-        repo = Repo.clone_from(source, dest)
-        repo.git.checkout(branch)
+        if depth:
+            Repo.clone_from(source, dest, branch=branch, depth=depth)
+        else:
+            Repo.clone_from(source, dest, branch=branch)
 
-    def install(self, source, branch="master", dest=None):
+    def install(self, source, branch="master", dest=None, depth=None):
         url_parts = self.parse_url(source)
         branch_name = url_parts.path.strip("/").split("/")[-1]
         if dest:
@@ -63,9 +65,9 @@
         if not os.path.exists(dest_dir):
             mkdir(dest_dir, perms=0o755)
         try:
-            self.clone(source, dest_dir, branch)
+            self.clone(source, dest_dir, branch, depth)
         except GitCommandError as e:
-            raise UnhandledSource(e.message)
+            raise UnhandledSource(e)
         except OSError as e:
             raise UnhandledSource(e.strerror)
         return dest_dir