Merge lp:~brad-marshall/charms/trusty/percona-cluster/fix-nagios into lp:~openstack-charmers-archive/charms/trusty/percona-cluster/next

[Brad Marshall]

Synced charmhelpers, added nagios_servicegroup config option

[lp:~brad-marshall/charms/trusty/percona-cluster/fix-nagios]

48. By Liam Young on 2015-02-26

[hopem, r=niedbalski,gnuoy] Synced charm-helpers to get fix for LP #1423153

[Liam Young (gnuoy)]

update_nrpe_config() never seems to get called. The nrpe-external-master-relation-{joined,changed} symlinks are missing and update_nrpe_config() is not called from anyother hooks

review: Needs Fixing

[lp:~brad-marshall/charms/trusty/percona-cluster/fix-nagios]

49. By Billy Olsen on 2015-02-27

[hopem, r=wolsen] sync charm-helpers fix for LP #1425999

50. By Edward Hope-Morley on 2015-02-27

Reverted commit r49

51. By Jorge Niedbalski on 2015-02-27

[hopem, r=billy-olsen, niedbalski] Fixes bug LP: #1425999

52. By Brad Marshall on 2015-03-03

[bradm] Add nagios checks, sync charmhelpers, merged with upstream

[Brad Marshall (brad-marshall)]

This should be fixed, and now ready for a re-review

review: Needs Resubmitting

[Liam Young (gnuoy)]

Approve

review: Approve

=== modified file 'charm-helpers.yaml'
--- charm-helpers.yaml	2015-02-10 11:16:27 +0000
+++ charm-helpers.yaml	2015-03-03 02:26:44 +0000
@@ -8,3 +8,4 @@
     - payload.execd
     - contrib.network.ip
     - contrib.database
+    - contrib.charmsupport

=== modified file 'config.yaml'
--- config.yaml	2015-02-16 14:12:42 +0000
+++ config.yaml	2015-03-03 02:26:44 +0000
@@ -77,4 +77,19 @@
     type: boolean
     default: False
     description: Adds two config options (wsrep_drupal_282555_workaround and wsrep_retry_autocommit) as a workaround for Percona Primary Key bug (see lplp1366997).
-
+  nagios_context:
+    default: "juju"
+    type: string
+    description: |
+      Used by the nrpe-external-master subordinate charm.
+      A string that will be prepended to instance name to set the host name
+      in nagios. So for instance the hostname would be something like:
+          juju-myservice-0
+      If you're running multiple environments with the same services in them
+      this allows you to differentiate between them.
+  nagios_servicegroups:
+    default: ""
+    type: string
+    description: |
+        A comma-separated list of nagios servicegroups.
+        If left empty, the nagios_context will be used as the servicegroup

=== added directory 'hooks/charmhelpers/contrib/charmsupport'
=== added file 'hooks/charmhelpers/contrib/charmsupport/__init__.py'
--- hooks/charmhelpers/contrib/charmsupport/__init__.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/contrib/charmsupport/__init__.py	2015-03-03 02:26:44 +0000
@@ -0,0 +1,15 @@
+# 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/>.

=== added file 'hooks/charmhelpers/contrib/charmsupport/nrpe.py'
--- hooks/charmhelpers/contrib/charmsupport/nrpe.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/contrib/charmsupport/nrpe.py	2015-03-03 02:26:44 +0000
@@ -0,0 +1,358 @@
+# 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/>.
+
+"""Compatibility with the nrpe-external-master charm"""
+# Copyright 2012 Canonical Ltd.
+#
+# Authors:
+#  Matthew Wedgwood <[e-mail]>
+
+import subprocess
+import pwd
+import grp
+import os
+import glob
+import shutil
+import re
+import shlex
+import yaml
+
+from charmhelpers.core.hookenv import (
+    config,
+    local_unit,
+    log,
+    relation_ids,
+    relation_set,
+    relations_of_type,
+)
+
+from charmhelpers.core.host import service
+
+# This module adds compatibility with the nrpe-external-master and plain nrpe
+# subordinate charms. To use it in your charm:
+#
+# 1. Update metadata.yaml
+#
+#   provides:
+#     (...)
+#     nrpe-external-master:
+#       interface: nrpe-external-master
+#       scope: container
+#
+#   and/or
+#
+#   provides:
+#     (...)
+#     local-monitors:
+#       interface: local-monitors
+#       scope: container
+
+#
+# 2. Add the following to config.yaml
+#
+#    nagios_context:
+#      default: "juju"
+#      type: string
+#      description: |
+#        Used by the nrpe subordinate charms.
+#        A string that will be prepended to instance name to set the host name
+#        in nagios. So for instance the hostname would be something like:
+#            juju-myservice-0
+#        If you're running multiple environments with the same services in them
+#        this allows you to differentiate between them.
+#    nagios_servicegroups:
+#      default: ""
+#      type: string
+#      description: |
+#        A comma-separated list of nagios servicegroups.
+#        If left empty, the nagios_context will be used as the servicegroup
+#
+# 3. Add custom checks (Nagios plugins) to files/nrpe-external-master
+#
+# 4. Update your hooks.py with something like this:
+#
+#    from charmsupport.nrpe import NRPE
+#    (...)
+#    def update_nrpe_config():
+#        nrpe_compat = NRPE()
+#        nrpe_compat.add_check(
+#            shortname = "myservice",
+#            description = "Check MyService",
+#            check_cmd = "check_http -w 2 -c 10 http://localhost"
+#            )
+#        nrpe_compat.add_check(
+#            "myservice_other",
+#            "Check for widget failures",
+#            check_cmd = "/srv/myapp/scripts/widget_check"
+#            )
+#        nrpe_compat.write()
+#
+#    def config_changed():
+#        (...)
+#        update_nrpe_config()
+#
+#    def nrpe_external_master_relation_changed():
+#        update_nrpe_config()
+#
+#    def local_monitors_relation_changed():
+#        update_nrpe_config()
+#
+# 5. ln -s hooks.py nrpe-external-master-relation-changed
+#    ln -s hooks.py local-monitors-relation-changed
+
+
+class CheckException(Exception):
+    pass
+
+
+class Check(object):
+    shortname_re = '[A-Za-z0-9-_]+$'
+    service_template = ("""
+#---------------------------------------------------
+# This file is Juju managed
+#---------------------------------------------------
+define service {{
+    use                             active-service
+    host_name                       {nagios_hostname}
+    service_description             {nagios_hostname}[{shortname}] """
+                        """{description}
+    check_command                   check_nrpe!{command}
+    servicegroups                   {nagios_servicegroup}
+}}
+""")
+
+    def __init__(self, shortname, description, check_cmd):
+        super(Check, self).__init__()
+        # XXX: could be better to calculate this from the service name
+        if not re.match(self.shortname_re, shortname):
+            raise CheckException("shortname must match {}".format(
+                Check.shortname_re))
+        self.shortname = shortname
+        self.command = "check_{}".format(shortname)
+        # Note: a set of invalid characters is defined by the
+        # Nagios server config
+        # The default is: illegal_object_name_chars=`~!$%^&*"|'<>?,()=
+        self.description = description
+        self.check_cmd = self._locate_cmd(check_cmd)
+
+    def _locate_cmd(self, check_cmd):
+        search_path = (
+            '/usr/lib/nagios/plugins',
+            '/usr/local/lib/nagios/plugins',
+        )
+        parts = shlex.split(check_cmd)
+        for path in search_path:
+            if os.path.exists(os.path.join(path, parts[0])):
+                command = os.path.join(path, parts[0])
+                if len(parts) > 1:
+                    command += " " + " ".join(parts[1:])
+                return command
+        log('Check command not found: {}'.format(parts[0]))
+        return ''
+
+    def write(self, nagios_context, hostname, nagios_servicegroups):
+        nrpe_check_file = '/etc/nagios/nrpe.d/{}.cfg'.format(
+            self.command)
+        with open(nrpe_check_file, 'w') as nrpe_check_config:
+            nrpe_check_config.write("# check {}\n".format(self.shortname))
+            nrpe_check_config.write("command[{}]={}\n".format(
+                self.command, self.check_cmd))
+
+        if not os.path.exists(NRPE.nagios_exportdir):
+            log('Not writing service config as {} is not accessible'.format(
+                NRPE.nagios_exportdir))
+        else:
+            self.write_service_config(nagios_context, hostname,
+                                      nagios_servicegroups)
+
+    def write_service_config(self, nagios_context, hostname,
+                             nagios_servicegroups):
+        for f in os.listdir(NRPE.nagios_exportdir):
+            if re.search('.*{}.cfg'.format(self.command), f):
+                os.remove(os.path.join(NRPE.nagios_exportdir, f))
+
+        templ_vars = {
+            'nagios_hostname': hostname,
+            'nagios_servicegroup': nagios_servicegroups,
+            'description': self.description,
+            'shortname': self.shortname,
+            'command': self.command,
+        }
+        nrpe_service_text = Check.service_template.format(**templ_vars)
+        nrpe_service_file = '{}/service__{}_{}.cfg'.format(
+            NRPE.nagios_exportdir, hostname, self.command)
+        with open(nrpe_service_file, 'w') as nrpe_service_config:
+            nrpe_service_config.write(str(nrpe_service_text))
+
+    def run(self):
+        subprocess.call(self.check_cmd)
+
+
+class NRPE(object):
+    nagios_logdir = '/var/log/nagios'
+    nagios_exportdir = '/var/lib/nagios/export'
+    nrpe_confdir = '/etc/nagios/nrpe.d'
+
+    def __init__(self, hostname=None):
+        super(NRPE, self).__init__()
+        self.config = config()
+        self.nagios_context = self.config['nagios_context']
+        if 'nagios_servicegroups' in self.config and self.config['nagios_servicegroups']:
+            self.nagios_servicegroups = self.config['nagios_servicegroups']
+        else:
+            self.nagios_servicegroups = self.nagios_context
+        self.unit_name = local_unit().replace('/', '-')
+        if hostname:
+            self.hostname = hostname
+        else:
+            self.hostname = "{}-{}".format(self.nagios_context, self.unit_name)
+        self.checks = []
+
+    def add_check(self, *args, **kwargs):
+        self.checks.append(Check(*args, **kwargs))
+
+    def write(self):
+        try:
+            nagios_uid = pwd.getpwnam('nagios').pw_uid
+            nagios_gid = grp.getgrnam('nagios').gr_gid
+        except:
+            log("Nagios user not set up, nrpe checks not updated")
+            return
+
+        if not os.path.exists(NRPE.nagios_logdir):
+            os.mkdir(NRPE.nagios_logdir)
+            os.chown(NRPE.nagios_logdir, nagios_uid, nagios_gid)
+
+        nrpe_monitors = {}
+        monitors = {"monitors": {"remote": {"nrpe": nrpe_monitors}}}
+        for nrpecheck in self.checks:
+            nrpecheck.write(self.nagios_context, self.hostname,
+                            self.nagios_servicegroups)
+            nrpe_monitors[nrpecheck.shortname] = {
+                "command": nrpecheck.command,
+            }
+
+        service('restart', 'nagios-nrpe-server')
+
+        for rid in relation_ids("local-monitors"):
+            relation_set(relation_id=rid, monitors=yaml.dump(monitors))
+
+
+def get_nagios_hostcontext(relation_name='nrpe-external-master'):
+    """
+    Query relation with nrpe subordinate, return the nagios_host_context
+
+    :param str relation_name: Name of relation nrpe sub joined to
+    """
+    for rel in relations_of_type(relation_name):
+        if 'nagios_hostname' in rel:
+            return rel['nagios_host_context']
+
+
+def get_nagios_hostname(relation_name='nrpe-external-master'):
+    """
+    Query relation with nrpe subordinate, return the nagios_hostname
+
+    :param str relation_name: Name of relation nrpe sub joined to
+    """
+    for rel in relations_of_type(relation_name):
+        if 'nagios_hostname' in rel:
+            return rel['nagios_hostname']
+
+
+def get_nagios_unit_name(relation_name='nrpe-external-master'):
+    """
+    Return the nagios unit name prepended with host_context if needed
+
+    :param str relation_name: Name of relation nrpe sub joined to
+    """
+    host_context = get_nagios_hostcontext(relation_name)
+    if host_context:
+        unit = "%s:%s" % (host_context, local_unit())
+    else:
+        unit = local_unit()
+    return unit
+
+
+def add_init_service_checks(nrpe, services, unit_name):
+    """
+    Add checks for each service in list
+
+    :param NRPE nrpe: NRPE object to add check to
+    :param list services: List of services to check
+    :param str unit_name: Unit name to use in check description
+    """
+    for svc in services:
+        upstart_init = '/etc/init/%s.conf' % svc
+        sysv_init = '/etc/init.d/%s' % svc
+        if os.path.exists(upstart_init):
+            nrpe.add_check(
+                shortname=svc,
+                description='process check {%s}' % unit_name,
+                check_cmd='check_upstart_job %s' % svc
+            )
+        elif os.path.exists(sysv_init):
+            cronpath = '/etc/cron.d/nagios-service-check-%s' % svc
+            cron_file = ('*/5 * * * * root '
+                         '/usr/local/lib/nagios/plugins/check_exit_status.pl '
+                         '-s /etc/init.d/%s status > '
+                         '/var/lib/nagios/service-check-%s.txt\n' % (svc,
+                                                                     svc)
+                         )
+            f = open(cronpath, 'w')
+            f.write(cron_file)
+            f.close()
+            nrpe.add_check(
+                shortname=svc,
+                description='process check {%s}' % unit_name,
+                check_cmd='check_status_file.py -f '
+                          '/var/lib/nagios/service-check-%s.txt' % svc,
+            )
+
+
+def copy_nrpe_checks():
+    """
+    Copy the nrpe checks into place
+
+    """
+    NAGIOS_PLUGINS = '/usr/local/lib/nagios/plugins'
+    nrpe_files_dir = os.path.join(os.getenv('CHARM_DIR'), 'hooks',
+                                  'charmhelpers', 'contrib', 'openstack',
+                                  'files')
+
+    if not os.path.exists(NAGIOS_PLUGINS):
+        os.makedirs(NAGIOS_PLUGINS)
+    for fname in glob.glob(os.path.join(nrpe_files_dir, "check_*")):
+        if os.path.isfile(fname):
+            shutil.copy2(fname,
+                         os.path.join(NAGIOS_PLUGINS, os.path.basename(fname)))
+
+
+def add_haproxy_checks(nrpe, unit_name):
+    """
+    Add checks for each service in list
+
+    :param NRPE nrpe: NRPE object to add check to
+    :param str unit_name: Unit name to use in check description
+    """
+    nrpe.add_check(
+        shortname='haproxy_servers',
+        description='Check HAProxy {%s}' % unit_name,
+        check_cmd='check_haproxy.sh')
+    nrpe.add_check(
+        shortname='haproxy_queue',
+        description='Check HAProxy queue depth {%s}' % unit_name,
+        check_cmd='check_haproxy_queue_depth.sh')

=== added file 'hooks/charmhelpers/contrib/charmsupport/volumes.py'
--- hooks/charmhelpers/contrib/charmsupport/volumes.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/contrib/charmsupport/volumes.py	2015-03-03 02:26:44 +0000
@@ -0,0 +1,175 @@
+# 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/>.
+
+'''
+Functions for managing volumes in juju units. One volume is supported per unit.
+Subordinates may have their own storage, provided it is on its own partition.
+
+Configuration stanzas::
+
+  volume-ephemeral:
+    type: boolean
+    default: true
+    description: >
+      If false, a volume is mounted as sepecified in "volume-map"
+      If true, ephemeral storage will be used, meaning that log data
+         will only exist as long as the machine. YOU HAVE BEEN WARNED.
+  volume-map:
+    type: string
+    default: {}
+    description: >
+      YAML map of units to device names, e.g:
+        "{ rsyslog/0: /dev/vdb, rsyslog/1: /dev/vdb }"
+      Service units will raise a configure-error if volume-ephemeral
+      is 'true' and no volume-map value is set. Use 'juju set' to set a
+      value and 'juju resolved' to complete configuration.
+
+Usage::
+
+    from charmsupport.volumes import configure_volume, VolumeConfigurationError
+    from charmsupport.hookenv import log, ERROR
+    def post_mount_hook():
+        stop_service('myservice')
+    def post_mount_hook():
+        start_service('myservice')
+
+    if __name__ == '__main__':
+        try:
+            configure_volume(before_change=pre_mount_hook,
+                             after_change=post_mount_hook)
+        except VolumeConfigurationError:
+            log('Storage could not be configured', ERROR)
+
+'''
+
+# XXX: Known limitations
+# - fstab is neither consulted nor updated
+
+import os
+from charmhelpers.core import hookenv
+from charmhelpers.core import host
+import yaml
+
+
+MOUNT_BASE = '/srv/juju/volumes'
+
+
+class VolumeConfigurationError(Exception):
+    '''Volume configuration data is missing or invalid'''
+    pass
+
+
+def get_config():
+    '''Gather and sanity-check volume configuration data'''
+    volume_config = {}
+    config = hookenv.config()
+
+    errors = False
+
+    if config.get('volume-ephemeral') in (True, 'True', 'true', 'Yes', 'yes'):
+        volume_config['ephemeral'] = True
+    else:
+        volume_config['ephemeral'] = False
+
+    try:
+        volume_map = yaml.safe_load(config.get('volume-map', '{}'))
+    except yaml.YAMLError as e:
+        hookenv.log("Error parsing YAML volume-map: {}".format(e),
+                    hookenv.ERROR)
+        errors = True
+    if volume_map is None:
+        # probably an empty string
+        volume_map = {}
+    elif not isinstance(volume_map, dict):
+        hookenv.log("Volume-map should be a dictionary, not {}".format(
+            type(volume_map)))
+        errors = True
+
+    volume_config['device'] = volume_map.get(os.environ['JUJU_UNIT_NAME'])
+    if volume_config['device'] and volume_config['ephemeral']:
+        # asked for ephemeral storage but also defined a volume ID
+        hookenv.log('A volume is defined for this unit, but ephemeral '
+                    'storage was requested', hookenv.ERROR)
+        errors = True
+    elif not volume_config['device'] and not volume_config['ephemeral']:
+        # asked for permanent storage but did not define volume ID
+        hookenv.log('Ephemeral storage was requested, but there is no volume '
+                    'defined for this unit.', hookenv.ERROR)
+        errors = True
+
+    unit_mount_name = hookenv.local_unit().replace('/', '-')
+    volume_config['mountpoint'] = os.path.join(MOUNT_BASE, unit_mount_name)
+
+    if errors:
+        return None
+    return volume_config
+
+
+def mount_volume(config):
+    if os.path.exists(config['mountpoint']):
+        if not os.path.isdir(config['mountpoint']):
+            hookenv.log('Not a directory: {}'.format(config['mountpoint']))
+            raise VolumeConfigurationError()
+    else:
+        host.mkdir(config['mountpoint'])
+    if os.path.ismount(config['mountpoint']):
+        unmount_volume(config)
+    if not host.mount(config['device'], config['mountpoint'], persist=True):
+        raise VolumeConfigurationError()
+
+
+def unmount_volume(config):
+    if os.path.ismount(config['mountpoint']):
+        if not host.umount(config['mountpoint'], persist=True):
+            raise VolumeConfigurationError()
+
+
+def managed_mounts():
+    '''List of all mounted managed volumes'''
+    return filter(lambda mount: mount[0].startswith(MOUNT_BASE), host.mounts())
+
+
+def configure_volume(before_change=lambda: None, after_change=lambda: None):
+    '''Set up storage (or don't) according to the charm's volume configuration.
+       Returns the mount point or "ephemeral". before_change and after_change
+       are optional functions to be called if the volume configuration changes.
+    '''
+
+    config = get_config()
+    if not config:
+        hookenv.log('Failed to read volume configuration', hookenv.CRITICAL)
+        raise VolumeConfigurationError()
+
+    if config['ephemeral']:
+        if os.path.ismount(config['mountpoint']):
+            before_change()
+            unmount_volume(config)
+            after_change()
+        return 'ephemeral'
+    else:
+        # persistent storage
+        if os.path.ismount(config['mountpoint']):
+            mounts = dict(managed_mounts())
+            if mounts.get(config['mountpoint']) != config['device']:
+                before_change()
+                unmount_volume(config)
+                mount_volume(config)
+                after_change()
+        else:
+            before_change()
+            mount_volume(config)
+            after_change()
+        return config['mountpoint']

=== modified file 'hooks/charmhelpers/contrib/database/mysql.py'
--- hooks/charmhelpers/contrib/database/mysql.py	2015-02-27 10:17:54 +0000
+++ hooks/charmhelpers/contrib/database/mysql.py	2015-03-03 02:26:44 +0000
@@ -1,6 +1,5 @@
 """Helper for working with a MySQL database"""
 import json
-import socket
 import re
 import sys
 import platform
@@ -22,7 +21,6 @@
     log,
     DEBUG,
     INFO,
-    WARNING,
 )
 from charmhelpers.fetch import (
     apt_install,

=== added file 'hooks/charmhelpers/core/strutils.py'
--- hooks/charmhelpers/core/strutils.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/strutils.py	2015-03-03 02:26:44 +0000
@@ -0,0 +1,42 @@
+#!/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/>.
+
+import six
+
+
+def bool_from_string(value):
+    """Interpret string value as boolean.
+
+    Returns True if value translates to True otherwise False.
+    """
+    if isinstance(value, six.string_types):
+        value = six.text_type(value)
+    else:
+        msg = "Unable to interpret non-string value '%s' as boolean" % (value)
+        raise ValueError(msg)
+
+    value = value.strip().lower()
+
+    if value in ['y', 'yes', 'true', 't']:
+        return True
+    elif value in ['n', 'no', 'false', 'f']:
+        return False
+
+    msg = "Unable to interpret string value '%s' as boolean" % (value)
+    raise ValueError(msg)

=== removed file 'hooks/charmhelpers/core/strutils.py'
--- hooks/charmhelpers/core/strutils.py	2015-02-25 20:48:34 +0000
+++ hooks/charmhelpers/core/strutils.py	1970-01-01 00:00:00 +0000
@@ -1,42 +0,0 @@
-#!/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/>.
-
-import six
-
-
-def bool_from_string(value):
-    """Interpret string value as boolean.
-
-    Returns True if value translates to True otherwise False.
-    """
-    if isinstance(value, six.string_types):
-        value = six.text_type(value)
-    else:
-        msg = "Unable to interpret non-string value '%s' as boolean" % (value)
-        raise ValueError(msg)
-
-    value = value.strip().lower()
-
-    if value in ['y', 'yes', 'true', 't']:
-        return True
-    elif value in ['n', 'no', 'false', 'f']:
-        return False
-
-    msg = "Unable to interpret string value '%s' as boolean" % (value)
-    raise ValueError(msg)

=== added file 'hooks/charmhelpers/core/unitdata.py'
--- hooks/charmhelpers/core/unitdata.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/unitdata.py	2015-03-03 02:26:44 +0000
@@ -0,0 +1,477 @@
+#!/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/>.
+#
+#
+# Authors:
+#  Kapil Thangavelu <[e-mail]>
+#
+"""
+Intro
+-----
+
+A simple way to store state in units. This provides a key value
+storage with support for versioned, transactional operation,
+and can calculate deltas from previous values to simplify unit logic
+when processing changes.
+
+
+Hook Integration
+----------------
+
+There are several extant frameworks for hook execution, including
+
+ - charmhelpers.core.hookenv.Hooks
+ - charmhelpers.core.services.ServiceManager
+
+The storage classes are framework agnostic, one simple integration is
+via the HookData contextmanager. It will record the current hook
+execution environment (including relation data, config data, etc.),
+setup a transaction and allow easy access to the changes from
+previously seen values. One consequence of the integration is the
+reservation of particular keys ('rels', 'unit', 'env', 'config',
+'charm_revisions') for their respective values.
+
+Here's a fully worked integration example using hookenv.Hooks::
+
+       from charmhelper.core import hookenv, unitdata
+
+       hook_data = unitdata.HookData()
+       db = unitdata.kv()
+       hooks = hookenv.Hooks()
+
+       @hooks.hook
+       def config_changed():
+           # Print all changes to configuration from previously seen
+           # values.
+           for changed, (prev, cur) in hook_data.conf.items():
+               print('config changed', changed,
+                     'previous value', prev,
+                     'current value',  cur)
+
+           # Get some unit specific bookeeping
+           if not db.get('pkg_key'):
+               key = urllib.urlopen('https://example.com/pkg_key').read()
+               db.set('pkg_key', key)
+
+           # Directly access all charm config as a mapping.
+           conf = db.getrange('config', True)
+
+           # Directly access all relation data as a mapping
+           rels = db.getrange('rels', True)
+
+       if __name__ == '__main__':
+           with hook_data():
+               hook.execute()
+
+
+A more basic integration is via the hook_scope context manager which simply
+manages transaction scope (and records hook name, and timestamp)::
+
+  >>> from unitdata import kv
+  >>> db = kv()
+  >>> with db.hook_scope('install'):
+  ...    # do work, in transactional scope.
+  ...    db.set('x', 1)
+  >>> db.get('x')
+  1
+
+
+Usage
+-----
+
+Values are automatically json de/serialized to preserve basic typing
+and complex data struct capabilities (dicts, lists, ints, booleans, etc).
+
+Individual values can be manipulated via get/set::
+
+   >>> kv.set('y', True)
+   >>> kv.get('y')
+   True
+
+   # We can set complex values (dicts, lists) as a single key.
+   >>> kv.set('config', {'a': 1, 'b': True'})
+
+   # Also supports returning dictionaries as a record which
+   # provides attribute access.
+   >>> config = kv.get('config', record=True)
+   >>> config.b
+   True
+
+
+Groups of keys can be manipulated with update/getrange::
+
+   >>> kv.update({'z': 1, 'y': 2}, prefix="gui.")
+   >>> kv.getrange('gui.', strip=True)
+   {'z': 1, 'y': 2}
+
+When updating values, its very helpful to understand which values
+have actually changed and how have they changed. The storage
+provides a delta method to provide for this::
+
+   >>> data = {'debug': True, 'option': 2}
+   >>> delta = kv.delta(data, 'config.')
+   >>> delta.debug.previous
+   None
+   >>> delta.debug.current
+   True
+   >>> delta
+   {'debug': (None, True), 'option': (None, 2)}
+
+Note the delta method does not persist the actual change, it needs to
+be explicitly saved via 'update' method::
+
+   >>> kv.update(data, 'config.')
+
+Values modified in the context of a hook scope retain historical values
+associated to the hookname.
+
+   >>> with db.hook_scope('config-changed'):
+   ...      db.set('x', 42)
+   >>> db.gethistory('x')
+   [(1, u'x', 1, u'install', u'2015-01-21T16:49:30.038372'),
+    (2, u'x', 42, u'config-changed', u'2015-01-21T16:49:30.038786')]
+
+"""
+
+import collections
+import contextlib
+import datetime
+import json
+import os
+import pprint
+import sqlite3
+import sys
+
+__author__ = 'Kapil Thangavelu <[e-mail]>'
+
+
+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.
+
+    To support dicts, lists, integer, floats, and booleans values
+    are automatically json encoded/decoded.
+    """
+    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')
+        self.conn = sqlite3.connect('%s' % self.db_path)
+        self.cursor = self.conn.cursor()
+        self.revision = None
+        self._closed = False
+        self._init()
+
+    def close(self):
+        if self._closed:
+            return
+        self.flush(False)
+        self.cursor.close()
+        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]))
+        result = self.cursor.fetchone()
+        if not result:
+            return default
+        if record:
+            return Record(json.loads(result[0]))
+        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))
+        result = self.cursor.fetchall()
+
+        if not result:
+            return None
+        if not strip:
+            key_prefix = ''
+        return dict([
+            (k[len(key_prefix):], json.loads(v)) for k, v in result])
+
+    def update(self, mapping, prefix=""):
+        for k, v in mapping.items():
+            self.set("%s%s" % (prefix, k), v)
+
+    def unset(self, key):
+        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 set(self, key, value):
+        serialized = json.dumps(value)
+
+        self.cursor.execute(
+            'select data from kv where key=?', [key])
+        exists = self.cursor.fetchone()
+
+        # Skip mutations to the same value
+        if exists:
+            if exists[0] == serialized:
+                return value
+
+        if not exists:
+            self.cursor.execute(
+                'insert into kv (key, data) values (?, ?)',
+                (key, serialized))
+        else:
+            self.cursor.execute('''
+            update kv
+            set data = ?
+            where key = ?''', [serialized, key])
+
+        # Save
+        if not self.revision:
+            return value
+
+        self.cursor.execute(
+            'select 1 from kv_revisions where key=? and revision=?',
+            [key, self.revision])
+        exists = self.cursor.fetchone()
+
+        if not exists:
+            self.cursor.execute(
+                '''insert into kv_revisions (
+                revision, key, data) values (?, ?, ?)''',
+                (self.revision, key, serialized))
+        else:
+            self.cursor.execute(
+                '''
+                update kv_revisions
+                set data = ?
+                where key = ?
+                and   revision = ?''',
+                [serialized, key, self.revision])
+
+        return value
+
+    def delta(self, mapping, prefix):
+        """
+        return a delta containing values that have changed.
+        """
+        previous = self.getrange(prefix, strip=True)
+        if not previous:
+            pk = set()
+        else:
+            pk = set(previous.keys())
+        ck = set(mapping.keys())
+        delta = DeltaSet()
+
+        # added
+        for k in ck.difference(pk):
+            delta[k] = Delta(None, mapping[k])
+
+        # removed
+        for k in pk.difference(ck):
+            delta[k] = Delta(previous[k], None)
+
+        # changed
+        for k in pk.intersection(ck):
+            c = mapping[k]
+            p = previous[k]
+            if c != p:
+                delta[k] = Delta(p, c)
+
+        return delta
+
+    @contextlib.contextmanager
+    def hook_scope(self, name=""):
+        """Scope all future interactions to the current hook execution
+        revision."""
+        assert not self.revision
+        self.cursor.execute(
+            'insert into hooks (hook, date) values (?, ?)',
+            (name or sys.argv[0],
+             datetime.datetime.utcnow().isoformat()))
+        self.revision = self.cursor.lastrowid
+        try:
+            yield self.revision
+            self.revision = None
+        except:
+            self.flush(False)
+            self.revision = None
+            raise
+        else:
+            self.flush()
+
+    def flush(self, save=True):
+        if save:
+            self.conn.commit()
+        elif self._closed:
+            return
+        else:
+            self.conn.rollback()
+
+    def _init(self):
+        self.cursor.execute('''
+            create table if not exists kv (
+               key text,
+               data text,
+               primary key (key)
+               )''')
+        self.cursor.execute('''
+            create table if not exists kv_revisions (
+               key text,
+               revision integer,
+               data text,
+               primary key (key, revision)
+               )''')
+        self.cursor.execute('''
+            create table if not exists hooks (
+               version integer primary key autoincrement,
+               hook text,
+               date text
+               )''')
+        self.conn.commit()
+
+    def gethistory(self, key, deserialize=False):
+        self.cursor.execute(
+            '''
+            select kv.revision, kv.key, kv.data, h.hook, h.date
+            from kv_revisions kv,
+                 hooks h
+            where kv.key=?
+             and kv.revision = h.version
+            ''', [key])
+        if deserialize is False:
+            return self.cursor.fetchall()
+        return map(_parse_history, self.cursor.fetchall())
+
+    def debug(self, fh=sys.stderr):
+        self.cursor.execute('select * from kv')
+        pprint.pprint(self.cursor.fetchall(), stream=fh)
+        self.cursor.execute('select * from kv_revisions')
+        pprint.pprint(self.cursor.fetchall(), stream=fh)
+
+
+def _parse_history(d):
+    return (d[0], d[1], json.loads(d[2]), d[3],
+            datetime.datetime.strptime(d[-1], "%Y-%m-%dT%H:%M:%S.%f"))
+
+
+class HookData(object):
+    """Simple integration for existing hook exec frameworks.
+
+    Records all unit information, and stores deltas for processing
+    by the hook.
+
+    Sample::
+
+       from charmhelper.core import hookenv, unitdata
+
+       changes = unitdata.HookData()
+       db = unitdata.kv()
+       hooks = hookenv.Hooks()
+
+       @hooks.hook
+       def config_changed():
+           # View all changes to configuration
+           for changed, (prev, cur) in changes.conf.items():
+               print('config changed', changed,
+                     'previous value', prev,
+                     'current value',  cur)
+
+           # Get some unit specific bookeeping
+           if not db.get('pkg_key'):
+               key = urllib.urlopen('https://example.com/pkg_key').read()
+               db.set('pkg_key', key)
+
+       if __name__ == '__main__':
+           with changes():
+               hook.execute()
+
+    """
+    def __init__(self):
+        self.kv = kv()
+        self.conf = None
+        self.rels = None
+
+    @contextlib.contextmanager
+    def __call__(self):
+        from charmhelpers.core import hookenv
+        hook_name = hookenv.hook_name()
+
+        with self.kv.hook_scope(hook_name):
+            self._record_charm_version(hookenv.charm_dir())
+            delta_config, delta_relation = self._record_hook(hookenv)
+            yield self.kv, delta_config, delta_relation
+
+    def _record_charm_version(self, charm_dir):
+        # Record revisions.. charm revisions are meaningless
+        # to charm authors as they don't control the revision.
+        # so logic dependnent on revision is not particularly
+        # useful, however it is useful for debugging analysis.
+        charm_rev = open(
+            os.path.join(charm_dir, 'revision')).read().strip()
+        charm_rev = charm_rev or '0'
+        revs = self.kv.get('charm_revisions', [])
+        if charm_rev not in revs:
+            revs.append(charm_rev.strip() or '0')
+            self.kv.set('charm_revisions', revs)
+
+    def _record_hook(self, hookenv):
+        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('unit', data['unit'])
+        self.kv.set('relid', data.get('relid'))
+        return conf_delta, rels_delta
+
+
+class Record(dict):
+
+    __slots__ = ()
+
+    def __getattr__(self, k):
+        if k in self:
+            return self[k]
+        raise AttributeError(k)
+
+
+class DeltaSet(Record):
+
+    __slots__ = ()
+
+
+Delta = collections.namedtuple('Delta', ['previous', 'current'])
+
+
+_KV = None
+
+
+def kv():
+    global _KV
+    if _KV is None:
+        _KV = Storage()
+    return _KV

=== removed file 'hooks/charmhelpers/core/unitdata.py'
--- hooks/charmhelpers/core/unitdata.py	2015-02-25 20:48:34 +0000
+++ hooks/charmhelpers/core/unitdata.py	1970-01-01 00:00:00 +0000
@@ -1,477 +0,0 @@
-#!/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/>.
-#
-#
-# Authors:
-#  Kapil Thangavelu <[e-mail]>
-#
-"""
-Intro
------
-
-A simple way to store state in units. This provides a key value
-storage with support for versioned, transactional operation,
-and can calculate deltas from previous values to simplify unit logic
-when processing changes.
-
-
-Hook Integration
-----------------
-
-There are several extant frameworks for hook execution, including
-
- - charmhelpers.core.hookenv.Hooks
- - charmhelpers.core.services.ServiceManager
-
-The storage classes are framework agnostic, one simple integration is
-via the HookData contextmanager. It will record the current hook
-execution environment (including relation data, config data, etc.),
-setup a transaction and allow easy access to the changes from
-previously seen values. One consequence of the integration is the
-reservation of particular keys ('rels', 'unit', 'env', 'config',
-'charm_revisions') for their respective values.
-
-Here's a fully worked integration example using hookenv.Hooks::
-
-       from charmhelper.core import hookenv, unitdata
-
-       hook_data = unitdata.HookData()
-       db = unitdata.kv()
-       hooks = hookenv.Hooks()
-
-       @hooks.hook
-       def config_changed():
-           # Print all changes to configuration from previously seen
-           # values.
-           for changed, (prev, cur) in hook_data.conf.items():
-               print('config changed', changed,
-                     'previous value', prev,
-                     'current value',  cur)
-
-           # Get some unit specific bookeeping
-           if not db.get('pkg_key'):
-               key = urllib.urlopen('https://example.com/pkg_key').read()
-               db.set('pkg_key', key)
-
-           # Directly access all charm config as a mapping.
-           conf = db.getrange('config', True)
-
-           # Directly access all relation data as a mapping
-           rels = db.getrange('rels', True)
-
-       if __name__ == '__main__':
-           with hook_data():
-               hook.execute()
-
-
-A more basic integration is via the hook_scope context manager which simply
-manages transaction scope (and records hook name, and timestamp)::
-
-  >>> from unitdata import kv
-  >>> db = kv()
-  >>> with db.hook_scope('install'):
-  ...    # do work, in transactional scope.
-  ...    db.set('x', 1)
-  >>> db.get('x')
-  1
-
-
-Usage
------
-
-Values are automatically json de/serialized to preserve basic typing
-and complex data struct capabilities (dicts, lists, ints, booleans, etc).
-
-Individual values can be manipulated via get/set::
-
-   >>> kv.set('y', True)
-   >>> kv.get('y')
-   True
-
-   # We can set complex values (dicts, lists) as a single key.
-   >>> kv.set('config', {'a': 1, 'b': True'})
-
-   # Also supports returning dictionaries as a record which
-   # provides attribute access.
-   >>> config = kv.get('config', record=True)
-   >>> config.b
-   True
-
-
-Groups of keys can be manipulated with update/getrange::
-
-   >>> kv.update({'z': 1, 'y': 2}, prefix="gui.")
-   >>> kv.getrange('gui.', strip=True)
-   {'z': 1, 'y': 2}
-
-When updating values, its very helpful to understand which values
-have actually changed and how have they changed. The storage
-provides a delta method to provide for this::
-
-   >>> data = {'debug': True, 'option': 2}
-   >>> delta = kv.delta(data, 'config.')
-   >>> delta.debug.previous
-   None
-   >>> delta.debug.current
-   True
-   >>> delta
-   {'debug': (None, True), 'option': (None, 2)}
-
-Note the delta method does not persist the actual change, it needs to
-be explicitly saved via 'update' method::
-
-   >>> kv.update(data, 'config.')
-
-Values modified in the context of a hook scope retain historical values
-associated to the hookname.
-
-   >>> with db.hook_scope('config-changed'):
-   ...      db.set('x', 42)
-   >>> db.gethistory('x')
-   [(1, u'x', 1, u'install', u'2015-01-21T16:49:30.038372'),
-    (2, u'x', 42, u'config-changed', u'2015-01-21T16:49:30.038786')]
-
-"""
-
-import collections
-import contextlib
-import datetime
-import json
-import os
-import pprint
-import sqlite3
-import sys
-
-__author__ = 'Kapil Thangavelu <[e-mail]>'
-
-
-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.
-
-    To support dicts, lists, integer, floats, and booleans values
-    are automatically json encoded/decoded.
-    """
-    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')
-        self.conn = sqlite3.connect('%s' % self.db_path)
-        self.cursor = self.conn.cursor()
-        self.revision = None
-        self._closed = False
-        self._init()
-
-    def close(self):
-        if self._closed:
-            return
-        self.flush(False)
-        self.cursor.close()
-        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]))
-        result = self.cursor.fetchone()
-        if not result:
-            return default
-        if record:
-            return Record(json.loads(result[0]))
-        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))
-        result = self.cursor.fetchall()
-
-        if not result:
-            return None
-        if not strip:
-            key_prefix = ''
-        return dict([
-            (k[len(key_prefix):], json.loads(v)) for k, v in result])
-
-    def update(self, mapping, prefix=""):
-        for k, v in mapping.items():
-            self.set("%s%s" % (prefix, k), v)
-
-    def unset(self, key):
-        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 set(self, key, value):
-        serialized = json.dumps(value)
-
-        self.cursor.execute(
-            'select data from kv where key=?', [key])
-        exists = self.cursor.fetchone()
-
-        # Skip mutations to the same value
-        if exists:
-            if exists[0] == serialized:
-                return value
-
-        if not exists:
-            self.cursor.execute(
-                'insert into kv (key, data) values (?, ?)',
-                (key, serialized))
-        else:
-            self.cursor.execute('''
-            update kv
-            set data = ?
-            where key = ?''', [serialized, key])
-
-        # Save
-        if not self.revision:
-            return value
-
-        self.cursor.execute(
-            'select 1 from kv_revisions where key=? and revision=?',
-            [key, self.revision])
-        exists = self.cursor.fetchone()
-
-        if not exists:
-            self.cursor.execute(
-                '''insert into kv_revisions (
-                revision, key, data) values (?, ?, ?)''',
-                (self.revision, key, serialized))
-        else:
-            self.cursor.execute(
-                '''
-                update kv_revisions
-                set data = ?
-                where key = ?
-                and   revision = ?''',
-                [serialized, key, self.revision])
-
-        return value
-
-    def delta(self, mapping, prefix):
-        """
-        return a delta containing values that have changed.
-        """
-        previous = self.getrange(prefix, strip=True)
-        if not previous:
-            pk = set()
-        else:
-            pk = set(previous.keys())
-        ck = set(mapping.keys())
-        delta = DeltaSet()
-
-        # added
-        for k in ck.difference(pk):
-            delta[k] = Delta(None, mapping[k])
-
-        # removed
-        for k in pk.difference(ck):
-            delta[k] = Delta(previous[k], None)
-
-        # changed
-        for k in pk.intersection(ck):
-            c = mapping[k]
-            p = previous[k]
-            if c != p:
-                delta[k] = Delta(p, c)
-
-        return delta
-
-    @contextlib.contextmanager
-    def hook_scope(self, name=""):
-        """Scope all future interactions to the current hook execution
-        revision."""
-        assert not self.revision
-        self.cursor.execute(
-            'insert into hooks (hook, date) values (?, ?)',
-            (name or sys.argv[0],
-             datetime.datetime.utcnow().isoformat()))
-        self.revision = self.cursor.lastrowid
-        try:
-            yield self.revision
-            self.revision = None
-        except:
-            self.flush(False)
-            self.revision = None
-            raise
-        else:
-            self.flush()
-
-    def flush(self, save=True):
-        if save:
-            self.conn.commit()
-        elif self._closed:
-            return
-        else:
-            self.conn.rollback()
-
-    def _init(self):
-        self.cursor.execute('''
-            create table if not exists kv (
-               key text,
-               data text,
-               primary key (key)
-               )''')
-        self.cursor.execute('''
-            create table if not exists kv_revisions (
-               key text,
-               revision integer,
-               data text,
-               primary key (key, revision)
-               )''')
-        self.cursor.execute('''
-            create table if not exists hooks (
-               version integer primary key autoincrement,
-               hook text,
-               date text
-               )''')
-        self.conn.commit()
-
-    def gethistory(self, key, deserialize=False):
-        self.cursor.execute(
-            '''
-            select kv.revision, kv.key, kv.data, h.hook, h.date
-            from kv_revisions kv,
-                 hooks h
-            where kv.key=?
-             and kv.revision = h.version
-            ''', [key])
-        if deserialize is False:
-            return self.cursor.fetchall()
-        return map(_parse_history, self.cursor.fetchall())
-
-    def debug(self, fh=sys.stderr):
-        self.cursor.execute('select * from kv')
-        pprint.pprint(self.cursor.fetchall(), stream=fh)
-        self.cursor.execute('select * from kv_revisions')
-        pprint.pprint(self.cursor.fetchall(), stream=fh)
-
-
-def _parse_history(d):
-    return (d[0], d[1], json.loads(d[2]), d[3],
-            datetime.datetime.strptime(d[-1], "%Y-%m-%dT%H:%M:%S.%f"))
-
-
-class HookData(object):
-    """Simple integration for existing hook exec frameworks.
-
-    Records all unit information, and stores deltas for processing
-    by the hook.
-
-    Sample::
-
-       from charmhelper.core import hookenv, unitdata
-
-       changes = unitdata.HookData()
-       db = unitdata.kv()
-       hooks = hookenv.Hooks()
-
-       @hooks.hook
-       def config_changed():
-           # View all changes to configuration
-           for changed, (prev, cur) in changes.conf.items():
-               print('config changed', changed,
-                     'previous value', prev,
-                     'current value',  cur)
-
-           # Get some unit specific bookeeping
-           if not db.get('pkg_key'):
-               key = urllib.urlopen('https://example.com/pkg_key').read()
-               db.set('pkg_key', key)
-
-       if __name__ == '__main__':
-           with changes():
-               hook.execute()
-
-    """
-    def __init__(self):
-        self.kv = kv()
-        self.conf = None
-        self.rels = None
-
-    @contextlib.contextmanager
-    def __call__(self):
-        from charmhelpers.core import hookenv
-        hook_name = hookenv.hook_name()
-
-        with self.kv.hook_scope(hook_name):
-            self._record_charm_version(hookenv.charm_dir())
-            delta_config, delta_relation = self._record_hook(hookenv)
-            yield self.kv, delta_config, delta_relation
-
-    def _record_charm_version(self, charm_dir):
-        # Record revisions.. charm revisions are meaningless
-        # to charm authors as they don't control the revision.
-        # so logic dependnent on revision is not particularly
-        # useful, however it is useful for debugging analysis.
-        charm_rev = open(
-            os.path.join(charm_dir, 'revision')).read().strip()
-        charm_rev = charm_rev or '0'
-        revs = self.kv.get('charm_revisions', [])
-        if charm_rev not in revs:
-            revs.append(charm_rev.strip() or '0')
-            self.kv.set('charm_revisions', revs)
-
-    def _record_hook(self, hookenv):
-        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('unit', data['unit'])
-        self.kv.set('relid', data.get('relid'))
-        return conf_delta, rels_delta
-
-
-class Record(dict):
-
-    __slots__ = ()
-
-    def __getattr__(self, k):
-        if k in self:
-            return self[k]
-        raise AttributeError(k)
-
-
-class DeltaSet(Record):
-
-    __slots__ = ()
-
-
-Delta = collections.namedtuple('Delta', ['previous', 'current'])
-
-
-_KV = None
-
-
-def kv():
-    global _KV
-    if _KV is None:
-        _KV = Storage()
-    return _KV

=== added symlink 'hooks/nrpe-external-master-relation-changed'
=== target is u'percona_hooks.py'
=== added symlink 'hooks/nrpe-external-master-relation-joined'
=== target is u'percona_hooks.py'
=== modified file 'hooks/percona_hooks.py'
--- hooks/percona_hooks.py	2015-02-16 14:12:42 +0000
+++ hooks/percona_hooks.py	2015-03-03 02:26:44 +0000
@@ -69,6 +69,8 @@
     is_address_in_network,
 )
 
+from charmhelpers.contrib.charmsupport import nrpe
+
 hooks = Hooks()
 
 LEADER_RES = 'grp_percona_cluster'
@@ -426,6 +428,23 @@
             relation_clear(r_id)
 
 
[e-mail]('nrpe-external-master-relation-joined',
+            'nrpe-external-master-relation-changed')
+def update_nrpe_config():
+    # python-dbus is used by check_upstart_job
+    apt_install('python-dbus')
+    hostname = nrpe.get_nagios_hostname()
+    current_unit = nrpe.get_nagios_unit_name()
+    nrpe_setup = nrpe.NRPE(hostname=hostname)
+    nrpe.add_init_service_checks(nrpe_setup, 'mysql', current_unit)
+    nrpe_setup.add_check(
+        shortname='mysql_proc',
+        description='Check MySQL process {%s}' % current_unit,
+        check_cmd='check_procs -c 1:1 -C mysqld'
+    )
+    nrpe_setup.write()
+
+
 def main():
     try:
         hooks.execute(sys.argv)