Merge lp:~brad-marshall/charms/trusty/ntp/add-nrpe-checks into lp:charms/trusty/ntp

[Brad Marshall]

Adds some basic nrpe checks for ntp.

[lp:~brad-marshall/charms/trusty/ntp/add-nrpe-checks]

24. By Brad Marshall on 2015-03-23

[bradm] Add ntpmon checks from paulgear

25. By Brad Marshall on 2015-03-23

[bradm] Adding missed string

[Marco Ceppi (marcoceppi)]

LGTM +1

review: Approve

=== modified file 'charm-helpers-sync.yaml'
--- charm-helpers-sync.yaml	2014-08-05 05:12:15 +0000
+++ charm-helpers-sync.yaml	2015-03-23 00:51:45 +0000
@@ -4,3 +4,4 @@
     - core
     - fetch
     - contrib.templating.jinja
+    - contrib.charmsupport

=== modified file 'config.yaml'
--- config.yaml	2014-06-20 14:08:13 +0000
+++ config.yaml	2015-03-23 00:51:45 +0000
@@ -1,5 +1,27 @@
 options:
   source:
-    default: 
+    default: ""
     type: string
     description: Space separated list of NTP servers to use as source for time.
+  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
+  nagios_ntpmon_checks:
+    default: "offset peers reachability sync"
+    type: string
+    description: |
+        A space-seperated list of nagios ntpmon checks to enable.
+        If left empty, no ntpmon checks will be used.

=== added directory 'files'
=== added directory 'files/nagios'
=== added file 'files/nagios/check_ntpd.pl'
--- files/nagios/check_ntpd.pl	1970-01-01 00:00:00 +0000
+++ files/nagios/check_ntpd.pl	2015-03-23 00:51:45 +0000
@@ -0,0 +1,154 @@
+#!/usr/bin/perl -w
+# Script from http://exchange.nagios.org/directory/Plugins/Network-Protocols/NTP-and-Time/check_ntpd/details
+
+use Getopt::Long;
+use strict;
+
+GetOptions(
+		"critical=i" => \(my $critical_threshold = '50'),
+		"warning=i" => \(my $warning_threshold = '75'),
+		"peer_critical=i" => \(my $peer_critical_threshold = '1'),
+		"peer_warning=i" => \(my $peer_warning_threshold = '2'),
+		"help" => \&display_help,
+);
+
+my $ntpq_path = `/usr/bin/which ntpq`;
+$ntpq_path =~ s/\n//g;
+my @server_list = `$ntpq_path -pn`;
+my %server_health;
+my $peer_count;
+my $overall_health = 0;
+my $good_count;
+my $selected_primary;
+my $selected_backup = 0;
+
+# Cleanup server list
+for(my $i = 0; $i < @server_list; $i++) {
+	if($server_list[$i] =~ /LOCAL/) {
+		splice(@server_list, $i, 1);
+		$i--;
+	} elsif($server_list[$i] =~ /^===/) {
+		splice(@server_list, $i, 1);
+		$i--;
+	} elsif($server_list[$i] =~ /jitter$/) {
+		splice(@server_list, $i, 1);
+		$i--;
+	} elsif($server_list[$i] =~ /^No association/) {
+		splice(@server_list, $i, 1);
+		$i--;
+	}
+}
+
+# Get number of peers
+$peer_count = @server_list;
+
+# Cycle through peers
+for(my $i = 0; $i < @server_list; $i++) {
+	#split each element of the peer line
+	my @tmp_array = split(" ", $server_list[$i]);
+
+	# Check for first character of peer
+	# space = Discarded due to high stratum and/or failed sanity checks.
+	# x = Designated falseticker by the intersection algorithm.
+	# . = Culled from the end of the candidate list.
+	# - = Discarded by the clustering algorithm.
+	# + = Included in the final selection set.
+	# # = Selected for synchronization but distance exceeds maximum.
+	# * = Selected for synchronization.
+	# o = Selected for synchronization, pps signal in use.
+	if(substr($tmp_array[0], 0, 1) eq '*') {
+		$selected_primary = "true";
+	} elsif(substr($tmp_array[0], 0, 1) eq '+') {
+		$selected_backup++;
+	}
+
+	$good_count = 0;
+	# Read in the octal number in column 6
+	my $rearch = oct($tmp_array[6]);
+
+	# while $rearch is not 0
+	while($rearch) {
+		# 1s place 0 or 1?
+		$good_count += $rearch % 2;
+		# Bit shift to the right
+		$rearch = $rearch >> 1;
+	}
+
+	# Calculate good packets received
+	$rearch = int(($good_count / 8) * 100);
+	
+	# Set percentage in hash
+	$server_health{$tmp_array[0]} = $rearch;
+}
+
+# Cycle through hash and tally weighted average of peer health
+while(my($key, $val) = each(%server_health)) {
+	$overall_health += $val * (1 / $peer_count);
+}
+
+########################### Nagios Status checks ###########################
+#if overall health is below critical threshold, crit
+if($overall_health <= $critical_threshold) {
+	print_overall_health("Critical");
+	print_server_list();
+	exit 2;
+}
+
+#if overall health is below warning and above critical threshold, warn
+if(($overall_health <= $warning_threshold) && ($overall_health > $critical_threshold)) {
+	print_overall_health("Warning");
+	print_server_list();
+	exit 1;
+}
+
+#if the number of peers is below the critical threshold, crit
+if($peer_count <= $peer_critical_threshold) {
+	print_overall_health("Critical");
+	print_server_list();
+	exit 2;
+#if the number of peers is below the warning threshold, warn
+} elsif($peer_count <= $peer_warning_threshold) {
+	print_overall_health("Warning");
+	print_server_list();
+	exit 1;
+}
+
+#check to make sure we have one backup and one selected ntp server
+#if there is no primary ntp server selected, crit
+if($selected_primary ne "true") {
+	print_overall_health("Critical");
+	print_server_list();
+	exit 2;
+#if there is no backup ntp server selected, warn
+} elsif($selected_backup < 1) {
+	print_overall_health("Warning");
+	print_server_list();
+	exit 1;
+}
+
+print_overall_health("OK");
+print_server_list();
+exit 0;
+
+sub print_server_list {
+	print "---------------------------\n";
+	while(my($key, $val) = each(%server_health)) {
+		print "Received " . $val . "% of the traffic from " . $key . "\n";
+	}
+}
+
+sub print_overall_health {
+	print $_[0] . " - NTPd Health is " . $overall_health . "% with " . $peer_count . " peers.\n";
+}
+
+sub display_help {
+	print "This nagios check is to determine the health of the NTPd client on the local system.  It uses the reach attribute from 'ntpq -pn' to determine the health of each listed peer, and determines the average health based on the number of peers.  For example, if there are 3 peers, and one peer has dropped 2 of the last 8 packets, it's health will be 75%.  This will result in an overall health of about 92% ((100+100+75) / 3).\n";
+	print "\n";
+	print "Available Options:\n";
+	print "\t--critical|-c <num>\t-Set the critical threshold for overall health (default:50)\n";
+	print "\t--warning|-w <num>\t-Set the warning threshold for overall health (default:75)\n";
+	print "\t--peer_critical <num>\t-Set the critical threshold for number of peers (default:1)\n";
+	print "\t--peer_warning <num>\t-Set the warning threshold for number of peers (default:2)\n";
+	print "\t--help|-h\t\t-display this help\n";
+	exit 0;
+}

=== added file 'files/nagios/check_ntpmon.py'
--- files/nagios/check_ntpmon.py	1970-01-01 00:00:00 +0000
+++ files/nagios/check_ntpmon.py	2015-03-23 00:51:45 +0000
@@ -0,0 +1,361 @@
+#!/usr/bin/python
+#
+# Author:       Paul Gear
+# Copyright:    (c) 2015 Gear Consulting Pty Ltd <http://libertysys.com.au/>
+# License:      GPLv3 <http://www.gnu.org/licenses/gpl.html>
+# Description:  NTP metrics as a Nagios check.
+#
+# This program is free software: you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free Software
+# Foundation, either version 3 of the License, or (at your option) any later
+# version.
+#
+# This program 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 General Public License for more
+# details.
+#
+# You should have received a copy of the GNU General Public License along with
+# this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+import argparse
+import re
+import subprocess
+import sys
+import traceback
+import warnings
+
+
+def ishostnamey(name):
+    """Return true if the passed name is roughly hostnamey.  NTP is rather casual about how it
+    reports hostnames and IP addresses, so we can't be too strict.  This function simply tests
+    that all of the characters in the string are letters, digits, dash, or period."""
+    return re.search(r'^[\w.-]*$', name) is not None and name.find('_') == -1
+
+
+def isipaddressy(name):
+    """Return true if the passed name is roughly IP addressy.  NTP is rather casual about how it
+    reports hostnames and IP addresses, so we can't be too strict.  This function simply tests
+    that all of the characters in the string are hexadecimal digits, period, or colon."""
+    return re.search(r'^[0-9a-f.:]*$', name) is not None
+
+
+class CheckNTPMon(object):
+
+    def __init__(self,
+                 warnpeers=2,
+                 okpeers=4,
+                 warnoffset=10,
+                 critoffset=50,
+                 warnreach=75,
+                 critreach=50):
+
+        self.warnpeers = warnpeers
+        self.okpeers = okpeers
+        self.warnoffset = warnoffset
+        self.critoffset = critoffset
+        self.warnreach = warnreach
+        self.critreach = critreach
+
+    def peers(self, n):
+        """Return 0 if the number of peers is OK
+        Return 1 if the number of peers is WARNING
+        Return 2 if the number of peers is CRITICAL"""
+        if n >= self.okpeers:
+            print "OK: %d usable peers" % n
+            return 0
+        elif n < self.warnpeers:
+            print "CRITICAL: Too few peers (%d) - must be at least %d" % (n, self.warnpeers)
+            return 2
+        else:
+            print "WARNING: Too few peers (%d) - should be at least %d" % (n, self.okpeers)
+            return 1
+
+    def offset(self, offset):
+        """Return 0 if the offset is OK
+        Return 1 if the offset is WARNING
+        Return 2 if the offset is CRITICAL"""
+        if abs(offset) > self.critoffset:
+            print "CRITICAL: Offset too high (%g) - must be less than %g" % \
+                    (offset, self.critoffset)
+            return 2
+        if abs(offset) > self.warnoffset:
+            print "WARNING: Offset too high (%g) - should be less than %g" % \
+                    (offset, self.warnoffset)
+            return 1
+        else:
+            print "OK: Offset normal (%g)" % (offset)
+            return 0
+
+    def reachability(self, percent):
+        """Return 0 if the reachability percentage is OK
+        Return 1 if the reachability percentage is warning
+        Return 2 if the reachability percentage is critical
+        Raise a ValueError if reachability is not a percentage"""
+        if percent < 0 or percent > 100:
+            raise ValueError('Value must be a percentage')
+        if percent <= self.critreach:
+            print "CRITICAL: Reachability too low (%g%%) - must be more than %g%%" % \
+                    (percent, self.critreach)
+            return 2
+        elif percent <= self.warnreach:
+            print "WARNING: Reachability too low (%g%%) - should be more than %g%%" % \
+                    (percent, self.warnreach)
+            return 1
+        else:
+            print "OK: Reachability normal (%g%%)" % (percent)
+            return 0
+
+    def sync(self, synchost):
+        """Return 0 if the synchost is non-zero in length and is a roughly valid host identifier, return 2 otherwise."""
+        synced = len(synchost) > 0 and (ishostnamey(synchost) or isipaddressy(synchost))
+        if synced:
+            print "OK: time is in sync with %s" % (synchost)
+        else:
+            print "CRITICAL: no sync host selected"
+        return 0 if synced else 2
+
+
+class NTPPeers(object):
+    """Turn the peer lines returned by 'ntpq -pn' into a data structure usable for checks."""
+
+    noiselines = [
+        r'remote\s+refid\s+st\s+t\s+when\s+poll\s+reach\s+',
+        r'^=*$',
+        r'No association ID.s returned',
+    ]
+    ignorepeers = [".LOCL.", ".INIT.", ".XFAC."]
+
+    def isnoiseline(self, line):
+        for regex in self.noiselines:
+            if re.search(regex, line) is not None:
+                return True
+        return False
+
+    def shouldignore(self, fields, l):
+        if len(fields) != 10:
+            warnings.warn('Invalid ntpq peer line - there are %d fields: %s' % (len(fields), l))
+            return True
+        if fields[1] in self.ignorepeers:
+            return True
+        if int(fields[2]) > 15:
+            return True
+        return False
+
+    def parsetally(self, tally, peerdata, offset):
+        """Parse the tally code and add the appropriate items to the peer data based on that code.
+           See the explanation of tally codes in the ntpq documentation for how these work:
+             - http://www.eecis.udel.edu/~mills/ntp/html/decode.html#peer
+             - http://www.eecis.udel.edu/~mills/ntp/html/ntpq.html
+             - http://psp2.ntp.org/bin/view/Support/TroubleshootingNTP
+        """
+        if tally in ['*', 'o'] and 'syncpeer' not in self.ntpdata:
+            # this is our sync peer
+            self.ntpdata['syncpeer'] = peerdata['peer']
+            self.ntpdata['offsetsyncpeer'] = offset
+            self.ntpdata['survivors'] += 1
+            self.ntpdata['offsetsurvivors'] += offset
+        elif tally in ['+', '#']:
+            # valid peer
+            self.ntpdata['survivors'] += 1
+            self.ntpdata['offsetsurvivors'] += offset
+        elif tally in [' ', 'x', '.', '-']:
+            # discarded peer
+            self.ntpdata['discards'] += 1
+            self.ntpdata['offsetdiscards'] += offset
+        else:
+            self.ntpdata['unknown'] += 1
+            return False
+        return True
+
+    def __init__(self, peerlines, check=None):
+        self.ntpdata = {
+            'survivors': 0,
+            'offsetsurvivors': 0,
+            'discards': 0,
+            'offsetdiscards': 0,
+            'unknown': 0,
+            'peers': 0,
+            'offsetall': 0,
+            'totalreach': 0,
+        }
+        self.check = check
+
+        for l in peerlines:
+            if self.isnoiseline(l):
+                continue
+
+            # first column is the tally field, the rest are whitespace-separated fields
+            tally = l[0]
+            fields = l[1:-1].split()
+
+            if self.shouldignore(fields, l):
+                continue
+
+            fieldnames = ['peer', 'refid', 'stratum', 'type', 'lastpoll', 'interval', 'reach',
+                          'delay', 'offset', 'jitter']
+            peerdata = dict(zip(fieldnames, fields))
+
+            offset = abs(float(peerdata['offset']))
+            if not self.parsetally(tally, peerdata, offset):
+                warnings.warn('Unknown tally code detected - please report a bug: %s' % (l))
+                continue
+
+            self.ntpdata['peers'] += 1
+            self.ntpdata['offsetall'] += offset
+
+            # reachability - this counts the number of bits set in the reachability field
+            # (which is displayed in octal in the ntpq output)
+            # http://stackoverflow.com/questions/9829578/fast-way-of-counting-bits-in-python
+            self.ntpdata['totalreach'] += bin(int(peerdata['reach'], 8)).count("1")
+
+        # reachability as a percentage of the last 8 polls, across all peers
+        self.ntpdata['reachability'] = float(self.ntpdata['totalreach']) * 100 / self.ntpdata['peers'] / 8
+
+        # average offsets
+        if self.ntpdata['survivors'] > 0:
+            self.ntpdata['averageoffsetsurvivors'] = \
+                    self.ntpdata['offsetsurvivors'] / self.ntpdata['survivors']
+        if self.ntpdata['discards'] > 0:
+            self.ntpdata['averageoffsetdiscards'] = \
+                    self.ntpdata['offsetdiscards'] / self.ntpdata['discards']
+        self.ntpdata['averageoffset'] = self.ntpdata['offsetall'] / self.ntpdata['peers']
+
+    def dump(self):
+        if self.ntpdata.get('syncpeer'):
+            print "Synced to: %s, offset %g ms" % \
+                    (self.ntpdata['syncpeer'], self.ntpdata['offsetsyncpeer'])
+        else:
+            print "No remote sync peer"
+        print "%d total peers, average offset %g ms" % \
+                (self.ntpdata['peers'], self.ntpdata['averageoffset'])
+        if self.ntpdata['survivors'] > 0:
+            print "%d good peers, average offset %g ms" % \
+                    (self.ntpdata['survivors'], self.ntpdata['averageoffsetsurvivors'])
+        if self.ntpdata['discards'] > 0:
+            print "%d discarded peers, average offset %g ms" % \
+                    (self.ntpdata['discards'], self.ntpdata['averageoffsetdiscards'])
+        print "Average reachability of all peers: %d%%" % (self.ntpdata['reachability'])
+
+    def check_peers(self, check=None):
+        """Check the number of usable peers"""
+        if check is None:
+            check = self.check if self.check else CheckNTPMon()
+        return check.peers(self.ntpdata['peers'])
+
+    def check_offset(self, check=None):
+        """Check the offset from the sync peer, returning critical, warning,
+        or OK based on the CheckNTPMon results.
+        If there is no sync peer, use the average offset of survivors instead.
+        If there are no survivors, use the average offset of discards instead, and return warning as a minimum.
+        If there are no discards, return critical.
+        """
+        if check is None:
+            check = self.check if self.check else CheckNTPMon()
+        if 'offsetsyncpeer' in self.ntpdata:
+            return check.offset(self.ntpdata['offsetsyncpeer'])
+        if 'averageoffsetsurvivors' in self.ntpdata:
+            return check.offset(self.ntpdata['averageoffsetsurvivors'])
+        if 'averageoffsetdiscards' in self.ntpdata:
+            result = check.offset(self.ntpdata['averageoffsetdiscards'])
+            return 1 if result < 1 else result
+        else:
+            print "CRITICAL: No peers for which to check offset"
+            return 2
+
+    def check_reachability(self, check=None):
+        """Check reachability of all peers"""
+        if check is None:
+            check = self.check if self.check else CheckNTPMon()
+        return check.reachability(self.ntpdata['reachability'])
+
+    def check_sync(self, check=None):
+        """Check whether host is in sync with a peer"""
+        if check is None:
+            check = self.check if self.check else CheckNTPMon()
+        if self.ntpdata.get('syncpeer') is None:
+            print "CRITICAL: No sync peer"
+            return 2
+        return check.sync(self.ntpdata['syncpeer'])
+
+    def checks(self, methods=None, check=None):
+        ret = 0
+        if not methods:
+            methods = [self.check_offset, self.check_peers, self.check_reachability, self.check_sync]
+        for method in methods:
+            check = method()
+            if ret < check:
+                ret = check
+        return ret
+
+    @staticmethod
+    def query():
+        lines = None
+        try:
+            output = subprocess.check_output(["ntpq", "-pn"])
+            lines = output.split("\n")
+        except:
+            traceback.print_exc(file=sys.stdout)
+        return lines
+
+
+def main():
+    methodnames = ['offset', 'peers', 'reachability', 'sync']
+    options = {
+        'warnpeers':  [  2, int,   'Minimum number of peers to be considered non-critical'],
+        'okpeers':    [  4, int,   'Minimum number of peers to be considered OK'],
+        'warnoffset': [ 10, float, 'Minimum offset to be considered warning'],
+        'critoffset': [ 50, float, 'Minimum offset to be considered critical'],
+        'warnreach':  [ 75, float, 'Minimum peer reachability percentage to be considered OK'],
+        'critreach':  [ 50, float, 'Minimum peer reachability percentage to be considered non-crtical'],
+    }
+
+    # Create check ranges; will be used by parse_args to store options
+    checkntpmon = CheckNTPMon()
+
+    # parse command line
+    parser = argparse.ArgumentParser(description='Nagios NTP check incorporating the logic of NTPmon')
+    parser.add_argument('--check', choices=methodnames,
+            help='Select check to run; if omitted, run all checks and return the worst result.')
+    parser.add_argument('--debug', action='store_true',
+            help='Include "ntpq -pn" output and internal state dump along with check results.')
+    for o in options.keys():
+        helptext = options[o][2] + ' (default: %d)' % (options[o][0])
+        parser.add_argument('--' + o, default=options[o][0], help=helptext, type=options[o][1])
+    args = parser.parse_args(namespace=checkntpmon)
+
+    # run ntpq
+    lines = NTPPeers.query()
+    if lines is None:
+        # Unknown result
+        print "Cannot get peers from ntpq."
+        print "Please check that an NTP server is installed and functional."
+        sys.exit(3)
+
+    # initialise our object with the results of ntpq and our preferred check thresholds
+    ntp = NTPPeers(lines, checkntpmon)
+
+    if args.debug:
+        print "\n".join(lines)
+        ntp.dump()
+
+    # work out which method to run
+    # (methods must be in the same order as methodnames above)
+    methods = [ntp.check_offset, ntp.check_peers, ntp.check_reachability, ntp.check_sync]
+    checkmethods = dict(zip(methodnames, methods))
+
+    # if check argument is specified, run just that check
+    ret = 0
+    if checkmethods.get(args.check):
+        method = checkmethods[args.check]
+        ret = method()
+    # else check all the methods
+    else:
+        ret = ntp.checks(methods)
+
+    sys.exit(ret)
+
+if __name__ == "__main__":
+    main()
+

=== modified file 'hooks/charmhelpers/__init__.py'
--- hooks/charmhelpers/__init__.py	2013-07-09 11:17:24 +0000
+++ hooks/charmhelpers/__init__.py	2015-03-23 00:51:45 +0000
@@ -0,0 +1,38 @@
+# 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/>.
+
+# Bootstrap charm-helpers, installing its dependencies if necessary using
+# only standard libraries.
+import subprocess
+import sys
+
+try:
+    import six  # flake8: noqa
+except ImportError:
+    if sys.version_info.major == 2:
+        subprocess.check_call(['apt-get', 'install', '-y', 'python-six'])
+    else:
+        subprocess.check_call(['apt-get', 'install', '-y', 'python3-six'])
+    import six  # flake8: noqa
+
+try:
+    import yaml  # flake8: noqa
+except ImportError:
+    if sys.version_info.major == 2:
+        subprocess.check_call(['apt-get', 'install', '-y', 'python-yaml'])
+    else:
+        subprocess.check_call(['apt-get', 'install', '-y', 'python3-yaml'])
+    import yaml  # flake8: noqa

=== modified file 'hooks/charmhelpers/contrib/__init__.py'
--- hooks/charmhelpers/contrib/__init__.py	2014-09-08 16:38:59 +0000
+++ hooks/charmhelpers/contrib/__init__.py	2015-03-23 00:51:45 +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 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	2015-03-23 00:51:45 +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	2015-03-23 00:51:45 +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	2015-03-23 00:51:45 +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/templating/__init__.py'
--- hooks/charmhelpers/contrib/templating/__init__.py	2014-09-08 16:38:59 +0000
+++ hooks/charmhelpers/contrib/templating/__init__.py	2015-03-23 00:51:45 +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/>.

=== modified file 'hooks/charmhelpers/contrib/templating/jinja.py'
--- hooks/charmhelpers/contrib/templating/jinja.py	2014-09-08 16:38:59 +0000
+++ hooks/charmhelpers/contrib/templating/jinja.py	2015-03-23 00:51:45 +0000
@@ -1,21 +1,37 @@
+# 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/>.
+
 """
 Templating using the python-jinja2 package.
 """
-from charmhelpers.fetch import (
-    apt_install,
-)
-
-
-DEFAULT_TEMPLATES_DIR = 'templates'
-
-
+import six
+from charmhelpers.fetch import apt_install
 try:
     import jinja2
 except ImportError:
-    apt_install(["python-jinja2"])
+    if six.PY3:
+        apt_install(["python3-jinja2"])
+    else:
+        apt_install(["python-jinja2"])
     import jinja2
 
 
+DEFAULT_TEMPLATES_DIR = 'templates'
+
+
 def render(template_name, context, template_dir=DEFAULT_TEMPLATES_DIR):
     templates = jinja2.Environment(
         loader=jinja2.FileSystemLoader(template_dir))

=== modified file 'hooks/charmhelpers/core/__init__.py'
--- hooks/charmhelpers/core/__init__.py	2013-07-09 11:17:24 +0000
+++ hooks/charmhelpers/core/__init__.py	2015-03-23 00:51:45 +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/core/decorators.py'
--- hooks/charmhelpers/core/decorators.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/decorators.py	2015-03-23 00:51:45 +0000
@@ -0,0 +1,57 @@
+# 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/>.
+
+#
+# Copyright 2014 Canonical Ltd.
+#
+# Authors:
+#  Edward Hope-Morley <[e-mail]>
+#
+
+import time
+
+from charmhelpers.core.hookenv import (
+    log,
+    INFO,
+)
+
+
+def retry_on_exception(num_retries, base_delay=0, exc_type=Exception):
+    """If the decorated function raises exception exc_type, allow num_retries
+    retry attempts before raise the exception.
+    """
+    def _retry_on_exception_inner_1(f):
+        def _retry_on_exception_inner_2(*args, **kwargs):
+            retries = num_retries
+            multiplier = 1
+            while True:
+                try:
+                    return f(*args, **kwargs)
+                except exc_type:
+                    if not retries:
+                        raise
+
+                delay = base_delay * multiplier
+                multiplier += 1
+                log("Retrying '%s' %d more times (delay=%s)" %
+                    (f.__name__, retries, delay), level=INFO)
+                retries -= 1
+                if delay:
+                    time.sleep(delay)
+
+        return _retry_on_exception_inner_2
+
+    return _retry_on_exception_inner_1

=== modified file 'hooks/charmhelpers/core/fstab.py'
--- hooks/charmhelpers/core/fstab.py	2014-07-16 05:40:55 +0000
+++ hooks/charmhelpers/core/fstab.py	2015-03-23 00:51:45 +0000
@@ -1,12 +1,29 @@
 #!/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 io
+import os
+
 __author__ = 'Jorge Niedbalski R. <[e-mail]>'
 
-import os
-
-
-class Fstab(file):
+
+class Fstab(io.FileIO):
     """This class extends file in order to implement a file reader/writer
     for file `/etc/fstab`
     """
@@ -24,8 +41,8 @@
                 options = "defaults"
 
             self.options = options
-            self.d = d
-            self.p = p
+            self.d = int(d)
+            self.p = int(p)
 
         def __eq__(self, o):
             return str(self) == str(o)
@@ -45,7 +62,7 @@
             self._path = path
         else:
             self._path = self.DEFAULT_PATH
-        file.__init__(self, self._path, 'r+')
+        super(Fstab, self).__init__(self._path, 'rb+')
 
     def _hydrate_entry(self, line):
         # NOTE: use split with no arguments to split on any
@@ -58,8 +75,9 @@
     def entries(self):
         self.seek(0)
         for line in self.readlines():
+            line = line.decode('us-ascii')
             try:
-                if not line.startswith("#"):
+                if line.strip() and not line.strip().startswith("#"):
                     yield self._hydrate_entry(line)
             except ValueError:
                 pass
@@ -75,18 +93,18 @@
         if self.get_entry_by_attr('device', entry.device):
             return False
 
-        self.write(str(entry) + '\n')
+        self.write((str(entry) + '\n').encode('us-ascii'))
         self.truncate()
         return entry
 
     def remove_entry(self, entry):
         self.seek(0)
 
-        lines = self.readlines()
+        lines = [l.decode('us-ascii') for l in self.readlines()]
 
         found = False
         for index, line in enumerate(lines):
-            if not line.startswith("#"):
+            if line.strip() and not line.strip().startswith("#"):
                 if self._hydrate_entry(line) == entry:
                     found = True
                     break
@@ -97,7 +115,7 @@
         lines.remove(line)
 
         self.seek(0)
-        self.write(''.join(lines))
+        self.write(''.join(lines).encode('us-ascii'))
         self.truncate()
         return True
 

=== modified file 'hooks/charmhelpers/core/hookenv.py'
--- hooks/charmhelpers/core/hookenv.py	2014-09-08 16:38:59 +0000
+++ hooks/charmhelpers/core/hookenv.py	2015-03-23 00:51:45 +0000
@@ -1,3 +1,19 @@
+# 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/>.
+
 "Interactions with the Juju environment"
 # Copyright 2013 Canonical Ltd.
 #
@@ -9,9 +25,14 @@
 import yaml
 import subprocess
 import sys
-import UserDict
 from subprocess import CalledProcessError
 
+import six
+if not six.PY3:
+    from UserDict import UserDict
+else:
+    from collections import UserDict
+
 CRITICAL = "CRITICAL"
 ERROR = "ERROR"
 WARNING = "WARNING"
@@ -63,16 +84,18 @@
     command = ['juju-log']
     if level:
         command += ['-l', level]
+    if not isinstance(message, six.string_types):
+        message = repr(message)
     command += [message]
     subprocess.call(command)
 
 
-class Serializable(UserDict.IterableUserDict):
+class Serializable(UserDict):
     """Wrapper, an object that can be serialized to yaml or json"""
 
     def __init__(self, obj):
         # wrap the object
-        UserDict.IterableUserDict.__init__(self)
+        UserDict.__init__(self)
         self.data = obj
 
     def __getattr__(self, attr):
@@ -203,6 +226,23 @@
         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))))
+
     def load_previous(self, path=None):
         """Load previous copy of config from disk.
 
@@ -252,7 +292,7 @@
 
         """
         if self._prev_dict:
-            for k, v in self._prev_dict.iteritems():
+            for k, v in six.iteritems(self._prev_dict):
                 if k not in self:
                     self[k] = v
         with open(self.path, 'w') as f:
@@ -267,7 +307,8 @@
         config_cmd_line.append(scope)
     config_cmd_line.append('--format=json')
     try:
-        config_data = json.loads(subprocess.check_output(config_cmd_line))
+        config_data = json.loads(
+            subprocess.check_output(config_cmd_line).decode('UTF-8'))
         if scope is not None:
             return config_data
         return Config(config_data)
@@ -286,10 +327,10 @@
     if unit:
         _args.append(unit)
     try:
-        return json.loads(subprocess.check_output(_args))
+        return json.loads(subprocess.check_output(_args).decode('UTF-8'))
     except ValueError:
         return None
-    except CalledProcessError, e:
+    except CalledProcessError as e:
         if e.returncode == 2:
             return None
         raise
@@ -301,7 +342,7 @@
     relation_cmd_line = ['relation-set']
     if relation_id is not None:
         relation_cmd_line.extend(('-r', relation_id))
-    for k, v in (relation_settings.items() + kwargs.items()):
+    for k, v in (list(relation_settings.items()) + list(kwargs.items())):
         if v is None:
             relation_cmd_line.append('{}='.format(k))
         else:
@@ -318,7 +359,8 @@
     relid_cmd_line = ['relation-ids', '--format=json']
     if reltype is not None:
         relid_cmd_line.append(reltype)
-        return json.loads(subprocess.check_output(relid_cmd_line)) or []
+        return json.loads(
+            subprocess.check_output(relid_cmd_line).decode('UTF-8')) or []
     return []
 
 
@@ -329,7 +371,8 @@
     units_cmd_line = ['relation-list', '--format=json']
     if relid is not None:
         units_cmd_line.extend(('-r', relid))
-    return json.loads(subprocess.check_output(units_cmd_line)) or []
+    return json.loads(
+        subprocess.check_output(units_cmd_line).decode('UTF-8')) or []
 
 
 @cached
@@ -369,21 +412,31 @@
 
 
 @cached
+def metadata():
+    """Get the current charm metadata.yaml contents as a python object"""
+    with open(os.path.join(charm_dir(), 'metadata.yaml')) as md:
+        return yaml.safe_load(md)
+
+
+@cached
 def relation_types():
     """Get a list of relation types supported by this charm"""
-    charmdir = os.environ.get('CHARM_DIR', '')
-    mdf = open(os.path.join(charmdir, 'metadata.yaml'))
-    md = yaml.safe_load(mdf)
     rel_types = []
+    md = metadata()
     for key in ('provides', 'requires', 'peers'):
         section = md.get(key)
         if section:
             rel_types.extend(section.keys())
-    mdf.close()
     return rel_types
 
 
 @cached
+def charm_name():
+    """Get the name of the current charm as is specified on metadata.yaml"""
+    return metadata().get('name')
+
+
+@cached
 def relations():
     """Get a nested dictionary of relation data for all related units"""
     rels = {}
@@ -438,7 +491,7 @@
     """Get the unit ID for the remote unit"""
     _args = ['unit-get', '--format=json', attribute]
     try:
-        return json.loads(subprocess.check_output(_args))
+        return json.loads(subprocess.check_output(_args).decode('UTF-8'))
     except ValueError:
         return None
 
@@ -475,9 +528,10 @@
             hooks.execute(sys.argv)
     """
 
-    def __init__(self):
+    def __init__(self, config_save=True):
         super(Hooks, self).__init__()
         self._hooks = {}
+        self._config_save = config_save
 
     def register(self, name, function):
         """Register a hook"""
@@ -488,9 +542,10 @@
         hook_name = os.path.basename(args[0])
         if hook_name in self._hooks:
             self._hooks[hook_name]()
-            cfg = config()
-            if cfg.implicit_save:
-                cfg.save()
+            if self._config_save:
+                cfg = config()
+                if cfg.implicit_save:
+                    cfg.save()
         else:
             raise UnregisteredHookError(hook_name)
 
@@ -511,3 +566,29 @@
 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])

=== modified file 'hooks/charmhelpers/core/host.py'
--- hooks/charmhelpers/core/host.py	2014-09-08 16:38:59 +0000
+++ hooks/charmhelpers/core/host.py	2015-03-23 00:51:45 +0000
@@ -1,3 +1,19 @@
+# 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/>.
+
 """Tools for working with the host system"""
 # Copyright 2012 Canonical Ltd.
 #
@@ -6,19 +22,20 @@
 #  Matthew Wedgwood <[e-mail]>
 
 import os
+import re
 import pwd
 import grp
 import random
 import string
 import subprocess
 import hashlib
-import shutil
 from contextlib import contextmanager
-
 from collections import OrderedDict
 
-from hookenv import log
-from fstab import Fstab
+import six
+
+from .hookenv import log
+from .fstab import Fstab
 
 
 def service_start(service_name):
@@ -54,7 +71,9 @@
 def service_running(service):
     """Determine whether a system service is running"""
     try:
-        output = subprocess.check_output(['service', service, 'status'], stderr=subprocess.STDOUT)
+        output = subprocess.check_output(
+            ['service', service, 'status'],
+            stderr=subprocess.STDOUT).decode('UTF-8')
     except subprocess.CalledProcessError:
         return False
     else:
@@ -67,9 +86,11 @@
 def service_available(service_name):
     """Determine whether a system service is available"""
     try:
-        subprocess.check_output(['service', service_name, 'status'], stderr=subprocess.STDOUT)
-    except subprocess.CalledProcessError:
-        return False
+        subprocess.check_output(
+            ['service', service_name, 'status'],
+            stderr=subprocess.STDOUT).decode('UTF-8')
+    except subprocess.CalledProcessError as e:
+        return 'unrecognized service' not in e.output
     else:
         return True
 
@@ -96,6 +117,26 @@
     return user_info
 
 
+def add_group(group_name, system_group=False):
+    """Add a group to the system"""
+    try:
+        group_info = grp.getgrnam(group_name)
+        log('group {0} already exists!'.format(group_name))
+    except KeyError:
+        log('creating group {0}'.format(group_name))
+        cmd = ['addgroup']
+        if system_group:
+            cmd.append('--system')
+        else:
+            cmd.extend([
+                '--group',
+            ])
+        cmd.append(group_name)
+        subprocess.check_call(cmd)
+        group_info = grp.getgrnam(group_name)
+    return group_info
+
+
 def add_user_to_group(username, group):
     """Add a user to a group"""
     cmd = [
@@ -115,7 +156,7 @@
     cmd.append(from_path)
     cmd.append(to_path)
     log(" ".join(cmd))
-    return subprocess.check_output(cmd).strip()
+    return subprocess.check_output(cmd).decode('UTF-8').strip()
 
 
 def symlink(source, destination):
@@ -130,28 +171,31 @@
     subprocess.check_call(cmd)
 
 
-def mkdir(path, owner='root', group='root', perms=0555, force=False):
+def mkdir(path, owner='root', group='root', perms=0o555, force=False):
     """Create a directory"""
     log("Making dir {} {}:{} {:o}".format(path, owner, group,
                                           perms))
     uid = pwd.getpwnam(owner).pw_uid
     gid = grp.getgrnam(group).gr_gid
     realpath = os.path.abspath(path)
-    if os.path.exists(realpath):
-        if force and not os.path.isdir(realpath):
+    path_exists = os.path.exists(realpath)
+    if path_exists and force:
+        if not os.path.isdir(realpath):
             log("Removing non-directory file {} prior to mkdir()".format(path))
             os.unlink(realpath)
-    else:
+            os.makedirs(realpath, perms)
+    elif not path_exists:
         os.makedirs(realpath, perms)
     os.chown(realpath, uid, gid)
-
-
-def write_file(path, content, owner='root', group='root', perms=0444):
-    """Create or overwrite a file with the contents of a string"""
+    os.chmod(realpath, perms)
+
+
+def write_file(path, content, owner='root', group='root', perms=0o444):
+    """Create or overwrite a file with the contents of a byte string."""
     log("Writing file {} {}:{} {:o}".format(path, owner, group, perms))
     uid = pwd.getpwnam(owner).pw_uid
     gid = grp.getgrnam(group).gr_gid
-    with open(path, 'w') as target:
+    with open(path, 'wb') as target:
         os.fchown(target.fileno(), uid, gid)
         os.fchmod(target.fileno(), perms)
         target.write(content)
@@ -177,7 +221,7 @@
     cmd_args.extend([device, mountpoint])
     try:
         subprocess.check_output(cmd_args)
-    except subprocess.CalledProcessError, e:
+    except subprocess.CalledProcessError as e:
         log('Error mounting {} at {}\n{}'.format(device, mountpoint, e.output))
         return False
 
@@ -191,7 +235,7 @@
     cmd_args = ['umount', mountpoint]
     try:
         subprocess.check_output(cmd_args)
-    except subprocess.CalledProcessError, e:
+    except subprocess.CalledProcessError as e:
         log('Error unmounting {}\n{}'.format(mountpoint, e.output))
         return False
 
@@ -209,17 +253,42 @@
     return system_mounts
 
 
-def file_hash(path):
-    """Generate a md5 hash of the contents of 'path' or None if not found """
+def file_hash(path, hash_type='md5'):
+    """
+    Generate a hash checksum of the contents of 'path' or None if not found.
+
+    :param str hash_type: Any hash alrgorithm supported by :mod:`hashlib`,
+                          such as md5, sha1, sha256, sha512, etc.
+    """
     if os.path.exists(path):
-        h = hashlib.md5()
-        with open(path, 'r') as source:
-            h.update(source.read())  # IGNORE:E1101 - it does have update
+        h = getattr(hashlib, hash_type)()
+        with open(path, 'rb') as source:
+            h.update(source.read())
         return h.hexdigest()
     else:
         return None
 
 
+def check_hash(path, checksum, hash_type='md5'):
+    """
+    Validate a file using a cryptographic checksum.
+
+    :param str checksum: Value of the checksum used to validate the file.
+    :param str hash_type: Hash algorithm used to generate `checksum`.
+        Can be any hash alrgorithm supported by :mod:`hashlib`,
+        such as md5, sha1, sha256, sha512, etc.
+    :raises ChecksumError: If the file fails the checksum
+
+    """
+    actual_checksum = file_hash(path, hash_type)
+    if checksum != actual_checksum:
+        raise ChecksumError("'%s' != '%s'" % (checksum, actual_checksum))
+
+
+class ChecksumError(ValueError):
+    pass
+
+
 def restart_on_change(restart_map, stopstart=False):
     """Restart services based on configuration files changing
 
@@ -236,11 +305,11 @@
     ceph_client_changed function.
     """
     def wrap(f):
-        def wrapped_f(*args):
+        def wrapped_f(*args, **kwargs):
             checksums = {}
             for path in restart_map:
                 checksums[path] = file_hash(path)
-            f(*args)
+            f(*args, **kwargs)
             restarts = []
             for path in restart_map:
                 if checksums[path] != file_hash(path):
@@ -270,29 +339,39 @@
 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.letters + string.digits)
+        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):
     '''Return a list of nics of given type(s)'''
-    if isinstance(nic_type, basestring):
+    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 + '*']
-        ip_output = subprocess.check_output(cmd).split('\n')
+        ip_output = subprocess.check_output(cmd).decode('UTF-8').split('\n')
         ip_output = (line for line in ip_output if line)
         for line in ip_output:
             if line.split()[1].startswith(int_type):
-                interfaces.append(line.split()[1].replace(":", ""))
+                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)
+
     return interfaces
 
 
@@ -304,7 +383,7 @@
 
 def get_nic_mtu(nic):
     cmd = ['ip', 'addr', 'show', nic]
-    ip_output = subprocess.check_output(cmd).split('\n')
+    ip_output = subprocess.check_output(cmd).decode('UTF-8').split('\n')
     mtu = ""
     for line in ip_output:
         words = line.split()
@@ -315,7 +394,7 @@
 
 def get_nic_hwaddr(nic):
     cmd = ['ip', '-o', '-0', 'addr', 'show', nic]
-    ip_output = subprocess.check_output(cmd)
+    ip_output = subprocess.check_output(cmd).decode('UTF-8')
     hwaddr = ""
     words = ip_output.split()
     if 'link/ether' in words:
@@ -330,10 +409,13 @@
     *  0 => Installed revno is the same as supplied arg
     * -1 => Installed revno is less than supplied arg
 
+    This function imports apt_cache function from charmhelpers.fetch if
+    the pkgcache argument is None. Be sure to add charmhelpers.fetch if
+    you call this function, or pass an apt_pkg.Cache() instance.
     '''
     import apt_pkg
-    from charmhelpers.fetch import apt_cache
     if not pkgcache:
+        from charmhelpers.fetch import apt_cache
         pkgcache = apt_cache()
     pkg = pkgcache[package]
     return apt_pkg.version_compare(pkg.current_ver.ver_str, revno)
@@ -348,13 +430,21 @@
         os.chdir(cur)
 
 
-def chownr(path, owner, group):
+def chownr(path, owner, group, follow_links=True):
     uid = pwd.getpwnam(owner).pw_uid
     gid = grp.getgrnam(group).gr_gid
+    if follow_links:
+        chown = os.chown
+    else:
+        chown = os.lchown
 
     for root, dirs, files in os.walk(path):
         for name in dirs + files:
             full = os.path.join(root, name)
             broken_symlink = os.path.lexists(full) and not os.path.exists(full)
             if not broken_symlink:
-                os.chown(full, uid, gid)
+                chown(full, uid, gid)
+
+
+def lchownr(path, owner, group):
+    chownr(path, owner, group, follow_links=False)

=== added directory 'hooks/charmhelpers/core/services'
=== added file 'hooks/charmhelpers/core/services/__init__.py'
--- hooks/charmhelpers/core/services/__init__.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/services/__init__.py	2015-03-23 00:51:45 +0000
@@ -0,0 +1,18 @@
+# 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/>.
+
+from .base import *  # NOQA
+from .helpers import *  # NOQA

=== added file 'hooks/charmhelpers/core/services/base.py'
--- hooks/charmhelpers/core/services/base.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/services/base.py	2015-03-23 00:51:45 +0000
@@ -0,0 +1,329 @@
+# 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 os
+import re
+import json
+from collections import Iterable
+
+from charmhelpers.core import host
+from charmhelpers.core import hookenv
+
+
+__all__ = ['ServiceManager', 'ManagerCallback',
+           'PortManagerCallback', 'open_ports', 'close_ports', 'manage_ports',
+           'service_restart', 'service_stop']
+
+
+class ServiceManager(object):
+    def __init__(self, services=None):
+        """
+        Register a list of services, given their definitions.
+
+        Service definitions are dicts in the following formats (all keys except
+        'service' are optional)::
+
+            {
+                "service": <service name>,
+                "required_data": <list of required data contexts>,
+                "provided_data": <list of provided data contexts>,
+                "data_ready": <one or more callbacks>,
+                "data_lost": <one or more callbacks>,
+                "start": <one or more callbacks>,
+                "stop": <one or more callbacks>,
+                "ports": <list of ports to manage>,
+            }
+
+        The 'required_data' list should contain dicts of required data (or
+        dependency managers that act like dicts and know how to collect the data).
+        Only when all items in the 'required_data' list are populated are the list
+        of 'data_ready' and 'start' callbacks executed.  See `is_ready()` for more
+        information.
+
+        The 'provided_data' list should contain relation data providers, most likely
+        a subclass of :class:`charmhelpers.core.services.helpers.RelationContext`,
+        that will indicate a set of data to set on a given relation.
+
+        The 'data_ready' value should be either a single callback, or a list of
+        callbacks, to be called when all items in 'required_data' pass `is_ready()`.
+        Each callback will be called with the service name as the only parameter.
+        After all of the 'data_ready' callbacks are called, the 'start' callbacks
+        are fired.
+
+        The 'data_lost' value should be either a single callback, or a list of
+        callbacks, to be called when a 'required_data' item no longer passes
+        `is_ready()`.  Each callback will be called with the service name as the
+        only parameter.  After all of the 'data_lost' callbacks are called,
+        the 'stop' callbacks are fired.
+
+        The 'start' value should be either a single callback, or a list of
+        callbacks, to be called when starting the service, after the 'data_ready'
+        callbacks are complete.  Each callback will be called with the service
+        name as the only parameter.  This defaults to
+        `[host.service_start, services.open_ports]`.
+
+        The 'stop' value should be either a single callback, or a list of
+        callbacks, to be called when stopping the service.  If the service is
+        being stopped because it no longer has all of its 'required_data', this
+        will be called after all of the 'data_lost' callbacks are complete.
+        Each callback will be called with the service name as the only parameter.
+        This defaults to `[services.close_ports, host.service_stop]`.
+
+        The 'ports' value should be a list of ports to manage.  The default
+        'start' handler will open the ports after the service is started,
+        and the default 'stop' handler will close the ports prior to stopping
+        the service.
+
+
+        Examples:
+
+        The following registers an Upstart service called bingod that depends on
+        a mongodb relation and which runs a custom `db_migrate` function prior to
+        restarting the service, and a Runit service called spadesd::
+
+            manager = services.ServiceManager([
+                {
+                    'service': 'bingod',
+                    'ports': [80, 443],
+                    'required_data': [MongoRelation(), config(), {'my': 'data'}],
+                    'data_ready': [
+                        services.template(source='bingod.conf'),
+                        services.template(source='bingod.ini',
+                                          target='/etc/bingod.ini',
+                                          owner='bingo', perms=0400),
+                    ],
+                },
+                {
+                    'service': 'spadesd',
+                    'data_ready': services.template(source='spadesd_run.j2',
+                                                    target='/etc/sv/spadesd/run',
+                                                    perms=0555),
+                    'start': runit_start,
+                    'stop': runit_stop,
+                },
+            ])
+            manager.manage()
+        """
+        self._ready_file = os.path.join(hookenv.charm_dir(), 'READY-SERVICES.json')
+        self._ready = None
+        self.services = {}
+        for service in services or []:
+            service_name = service['service']
+            self.services[service_name] = service
+
+    def manage(self):
+        """
+        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()
+
+    def provide_data(self):
+        """
+        Set the relation data for each provider in the ``provided_data`` list.
+
+        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.
+        """
+        hook_name = hookenv.hook_name()
+        for service in self.services.values():
+            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)
+
+    def reconfigure_services(self, *service_names):
+        """
+        Update all files for one or more registered services, and,
+        if ready, optionally restart them.
+
+        If no service names are given, reconfigures all registered services.
+        """
+        for service_name in service_names or self.services.keys():
+            if self.is_ready(service_name):
+                self.fire_event('data_ready', service_name)
+                self.fire_event('start', service_name, default=[
+                    service_restart,
+                    manage_ports])
+                self.save_ready(service_name)
+            else:
+                if self.was_ready(service_name):
+                    self.fire_event('data_lost', service_name)
+                self.fire_event('stop', service_name, default=[
+                    manage_ports,
+                    service_stop])
+                self.save_lost(service_name)
+
+    def stop_services(self, *service_names):
+        """
+        Stop one or more registered services, by name.
+
+        If no service names are given, stops all registered services.
+        """
+        for service_name in service_names or self.services.keys():
+            self.fire_event('stop', service_name, default=[
+                manage_ports,
+                service_stop])
+
+    def get_service(self, service_name):
+        """
+        Given the name of a registered service, return its service definition.
+        """
+        service = self.services.get(service_name)
+        if not service:
+            raise KeyError('Service not registered: %s' % service_name)
+        return service
+
+    def fire_event(self, event_name, service_name, default=None):
+        """
+        Fire a data_ready, data_lost, start, or stop event on a given service.
+        """
+        service = self.get_service(service_name)
+        callbacks = service.get(event_name, default)
+        if not callbacks:
+            return
+        if not isinstance(callbacks, Iterable):
+            callbacks = [callbacks]
+        for callback in callbacks:
+            if isinstance(callback, ManagerCallback):
+                callback(self, service_name, event_name)
+            else:
+                callback(service_name)
+
+    def is_ready(self, service_name):
+        """
+        Determine if a registered service is ready, by checking its 'required_data'.
+
+        A 'required_data' item can be any mapping type, and is considered ready
+        if `bool(item)` evaluates as True.
+        """
+        service = self.get_service(service_name)
+        reqs = service.get('required_data', [])
+        return all(bool(req) for req in reqs)
+
+    def _load_ready_file(self):
+        if self._ready is not None:
+            return
+        if os.path.exists(self._ready_file):
+            with open(self._ready_file) as fp:
+                self._ready = set(json.load(fp))
+        else:
+            self._ready = set()
+
+    def _save_ready_file(self):
+        if self._ready is None:
+            return
+        with open(self._ready_file, 'w') as fp:
+            json.dump(list(self._ready), fp)
+
+    def save_ready(self, service_name):
+        """
+        Save an indicator that the given service is now data_ready.
+        """
+        self._load_ready_file()
+        self._ready.add(service_name)
+        self._save_ready_file()
+
+    def save_lost(self, service_name):
+        """
+        Save an indicator that the given service is no longer data_ready.
+        """
+        self._load_ready_file()
+        self._ready.discard(service_name)
+        self._save_ready_file()
+
+    def was_ready(self, service_name):
+        """
+        Determine if the given service was previously data_ready.
+        """
+        self._load_ready_file()
+        return service_name in self._ready
+
+
+class ManagerCallback(object):
+    """
+    Special case of a callback that takes the `ServiceManager` instance
+    in addition to the service name.
+
+    Subclasses should implement `__call__` which should accept three parameters:
+
+        * `manager`       The `ServiceManager` instance
+        * `service_name`  The name of the service it's being triggered for
+        * `event_name`    The name of the event that this callback is handling
+    """
+    def __call__(self, manager, service_name, event_name):
+        raise NotImplementedError()
+
+
+class PortManagerCallback(ManagerCallback):
+    """
+    Callback class that will open or close ports, for use as either
+    a start or stop action.
+    """
+    def __call__(self, manager, service_name, event_name):
+        service = manager.get_service(service_name)
+        new_ports = service.get('ports', [])
+        port_file = os.path.join(hookenv.charm_dir(), '.{}.ports'.format(service_name))
+        if os.path.exists(port_file):
+            with open(port_file) as fp:
+                old_ports = fp.read().split(',')
+            for old_port in old_ports:
+                if bool(old_port):
+                    old_port = int(old_port)
+                    if old_port not in new_ports:
+                        hookenv.close_port(old_port)
+        with open(port_file, 'w') as fp:
+            fp.write(','.join(str(port) for port in new_ports))
+        for port in new_ports:
+            if event_name == 'start':
+                hookenv.open_port(port)
+            elif event_name == 'stop':
+                hookenv.close_port(port)
+
+
+def service_stop(service_name):
+    """
+    Wrapper around host.service_stop to prevent spurious "unknown service"
+    messages in the logs.
+    """
+    if host.service_running(service_name):
+        host.service_stop(service_name)
+
+
+def service_restart(service_name):
+    """
+    Wrapper around host.service_restart to prevent spurious "unknown service"
+    messages in the logs.
+    """
+    if host.service_available(service_name):
+        if host.service_running(service_name):
+            host.service_restart(service_name)
+        else:
+            host.service_start(service_name)
+
+
+# Convenience aliases
+open_ports = close_ports = manage_ports = PortManagerCallback()

=== added file 'hooks/charmhelpers/core/services/helpers.py'
--- hooks/charmhelpers/core/services/helpers.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/services/helpers.py	2015-03-23 00:51:45 +0000
@@ -0,0 +1,267 @@
+# 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 os
+import yaml
+from charmhelpers.core import hookenv
+from charmhelpers.core import templating
+
+from charmhelpers.core.services.base import ManagerCallback
+
+
+__all__ = ['RelationContext', 'TemplateCallback',
+           'render_template', 'template']
+
+
+class RelationContext(dict):
+    """
+    Base class for a context generator that gets relation data from juju.
+
+    Subclasses must provide the attributes `name`, which is the name of the
+    interface of interest, `interface`, which is the type of the interface of
+    interest, and `required_keys`, which is the set of keys required for the
+    relation to be considered complete.  The data for all interfaces matching
+    the `name` attribute that are complete will used to populate the dictionary
+    values (see `get_data`, below).
+
+    The generated context will be namespaced under the relation :attr:`name`,
+    to prevent potential naming conflicts.
+
+    :param str name: Override the relation :attr:`name`, since it can vary from charm to charm
+    :param list additional_required_keys: Extend the list of :attr:`required_keys`
+    """
+    name = None
+    interface = None
+
+    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:
+            self.required_keys.extend(additional_required_keys)
+        self.get_data()
+
+    def __bool__(self):
+        """
+        Returns True if all of the required_keys are available.
+        """
+        return self.is_ready()
+
+    __nonzero__ = __bool__
+
+    def __repr__(self):
+        return super(RelationContext, self).__repr__()
+
+    def is_ready(self):
+        """
+        Returns True if all of the `required_keys` are available from any units.
+        """
+        ready = len(self.get(self.name, [])) > 0
+        if not ready:
+            hookenv.log('Incomplete relation: {}'.format(self.__class__.__name__), hookenv.DEBUG)
+        return ready
+
+    def _is_ready(self, unit_data):
+        """
+        Helper method that tests a set of relation data and returns True if
+        all of the `required_keys` are present.
+        """
+        return set(unit_data.keys()).issuperset(set(self.required_keys))
+
+    def get_data(self):
+        """
+        Retrieve the relation data for each unit involved in a relation and,
+        if complete, store it in a list under `self[self.name]`.  This
+        is automatically called when the RelationContext is instantiated.
+
+        The units are sorted lexographically first by the service ID, then by
+        the unit ID.  Thus, if an interface has two other services, 'db:1'
+        and 'db:2', with 'db:1' having two units, 'wordpress/0' and 'wordpress/1',
+        and 'db:2' having one unit, 'mediawiki/0', all of which have a complete
+        set of data, the relation data for the units will be stored in the
+        order: 'wordpress/0', 'wordpress/1', 'mediawiki/0'.
+
+        If you only care about a single unit on the relation, you can just
+        access it as `{{ interface[0]['key'] }}`.  However, if you can at all
+        support multiple units on a relation, you should iterate over the list,
+        like::
+
+            {% for unit in interface -%}
+                {{ unit['key'] }}{% if not loop.last %},{% endif %}
+            {%- endfor %}
+
+        Note that since all sets of relation data from all related services and
+        units are in a single list, if you need to know which service or unit a
+        set of data came from, you'll need to extend this class to preserve
+        that information.
+        """
+        if not hookenv.relation_ids(self.name):
+            return
+
+        ns = self.setdefault(self.name, [])
+        for rid in sorted(hookenv.relation_ids(self.name)):
+            for unit in sorted(hookenv.related_units(rid)):
+                reldata = hookenv.relation_get(rid=rid, unit=unit)
+                if self._is_ready(reldata):
+                    ns.append(reldata)
+
+    def provide_data(self):
+        """
+        Return data to be relation_set for this interface.
+        """
+        return {}
+
+
+class MysqlRelation(RelationContext):
+    """
+    Relation context for the `mysql` interface.
+
+    :param str name: Override the relation :attr:`name`, since it can vary from charm to charm
+    :param list additional_required_keys: Extend the list of :attr:`required_keys`
+    """
+    name = 'db'
+    interface = 'mysql'
+
+    def __init__(self, *args, **kwargs):
+        self.required_keys = ['host', 'user', 'password', 'database']
+        super(HttpRelation).__init__(self, *args, **kwargs)
+
+
+class HttpRelation(RelationContext):
+    """
+    Relation context for the `http` interface.
+
+    :param str name: Override the relation :attr:`name`, since it can vary from charm to charm
+    :param list additional_required_keys: Extend the list of :attr:`required_keys`
+    """
+    name = 'website'
+    interface = 'http'
+
+    def __init__(self, *args, **kwargs):
+        self.required_keys = ['host', 'port']
+        super(HttpRelation).__init__(self, *args, **kwargs)
+
+    def provide_data(self):
+        return {
+            'host': hookenv.unit_get('private-address'),
+            'port': 80,
+        }
+
+
+class RequiredConfig(dict):
+    """
+    Data context that loads config options with one or more mandatory options.
+
+    Once the required options have been changed from their default values, all
+    config options will be available, namespaced under `config` to prevent
+    potential naming conflicts (for example, between a config option and a
+    relation property).
+
+    :param list *args: List of options that must be changed from their default values.
+    """
+
+    def __init__(self, *args):
+        self.required_options = args
+        self['config'] = hookenv.config()
+        with open(os.path.join(hookenv.charm_dir(), 'config.yaml')) as fp:
+            self.config = yaml.load(fp).get('options', {})
+
+    def __bool__(self):
+        for option in self.required_options:
+            if option not in self['config']:
+                return False
+            current_value = self['config'][option]
+            default_value = self.config[option].get('default')
+            if current_value == default_value:
+                return False
+            if current_value in (None, '') and default_value in (None, ''):
+                return False
+        return True
+
+    def __nonzero__(self):
+        return self.__bool__()
+
+
+class StoredContext(dict):
+    """
+    A data context that always returns the data that it was first created with.
+
+    This is useful to do a one-time generation of things like passwords, that
+    will thereafter use the same value that was originally generated, instead
+    of generating a new value each time it is run.
+    """
+    def __init__(self, file_name, config_data):
+        """
+        If the file exists, populate `self` with the data from the file.
+        Otherwise, populate with the given data and persist it to the file.
+        """
+        if os.path.exists(file_name):
+            self.update(self.read_context(file_name))
+        else:
+            self.store_context(file_name, config_data)
+            self.update(config_data)
+
+    def store_context(self, file_name, config_data):
+        if not os.path.isabs(file_name):
+            file_name = os.path.join(hookenv.charm_dir(), file_name)
+        with open(file_name, 'w') as file_stream:
+            os.fchmod(file_stream.fileno(), 0o600)
+            yaml.dump(config_data, file_stream)
+
+    def read_context(self, file_name):
+        if not os.path.isabs(file_name):
+            file_name = os.path.join(hookenv.charm_dir(), file_name)
+        with open(file_name, 'r') as file_stream:
+            data = yaml.load(file_stream)
+            if not data:
+                raise OSError("%s is empty" % file_name)
+            return data
+
+
+class TemplateCallback(ManagerCallback):
+    """
+    Callback class that will render a Jinja2 template, for use as a ready
+    action.
+
+    :param str source: The template source file, relative to
+    `$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
+    """
+    def __init__(self, source, target,
+                 owner='root', group='root', perms=0o444):
+        self.source = source
+        self.target = target
+        self.owner = owner
+        self.group = group
+        self.perms = perms
+
+    def __call__(self, manager, service_name, event_name):
+        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)
+
+
+# Convenience aliases for templates
+render_template = template = TemplateCallback

=== added file 'hooks/charmhelpers/core/strutils.py'
--- hooks/charmhelpers/core/strutils.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/strutils.py	2015-03-23 00:51:45 +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)

=== added file 'hooks/charmhelpers/core/sysctl.py'
--- hooks/charmhelpers/core/sysctl.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/sysctl.py	2015-03-23 00:51:45 +0000
@@ -0,0 +1,56 @@
+#!/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 yaml
+
+from subprocess import check_call
+
+from charmhelpers.core.hookenv import (
+    log,
+    DEBUG,
+    ERROR,
+)
+
+__author__ = 'Jorge Niedbalski R. <[e-mail]>'
+
+
+def create(sysctl_dict, sysctl_file):
+    """Creates a sysctl.conf file from a YAML associative array
+
+    :param sysctl_dict: a YAML-formatted string of sysctl options eg "{ 'kernel.max_pid': 1337 }"
+    :type sysctl_dict: str
+    :param sysctl_file: path to the sysctl file to be saved
+    :type sysctl_file: str or unicode
+    :returns: None
+    """
+    try:
+        sysctl_dict_parsed = yaml.safe_load(sysctl_dict)
+    except yaml.YAMLError:
+        log("Error parsing YAML sysctl_dict: {}".format(sysctl_dict),
+            level=ERROR)
+        return
+
+    with open(sysctl_file, "w") as fd:
+        for key, value in sysctl_dict_parsed.items():
+            fd.write("{}={}\n".format(key, value))
+
+    log("Updating sysctl_file: %s values: %s" % (sysctl_file, sysctl_dict_parsed),
+        level=DEBUG)
+
+    check_call(["sysctl", "-p", sysctl_file])

=== added file 'hooks/charmhelpers/core/templating.py'
--- hooks/charmhelpers/core/templating.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/templating.py	2015-03-23 00:51:45 +0000
@@ -0,0 +1,68 @@
+# 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 os
+
+from charmhelpers.core import host
+from charmhelpers.core import hookenv
+
+
+def render(source, target, context, owner='root', group='root',
+           perms=0o444, templates_dir=None, encoding='UTF-8'):
+    """
+    Render a template.
+
+    The `source` path, if not absolute, is relative to the `templates_dir`.
+
+    The `target` path should be absolute.
+
+    The context should be a dict containing the values to be replaced in the
+    template.
+
+    The `owner`, `group`, and `perms` options will be passed to `write_file`.
+
+    If omitted, `templates_dir` defaults to the `templates` folder in the charm.
+
+    Note: Using this requires python-jinja2; if it is not installed, calling
+    this will attempt to use charmhelpers.fetch.apt_install to install it.
+    """
+    try:
+        from jinja2 import FileSystemLoader, Environment, exceptions
+    except ImportError:
+        try:
+            from charmhelpers.fetch import apt_install
+        except ImportError:
+            hookenv.log('Could not import jinja2, and could not import '
+                        'charmhelpers.fetch to install it',
+                        level=hookenv.ERROR)
+            raise
+        apt_install('python-jinja2', fatal=True)
+        from jinja2 import FileSystemLoader, Environment, exceptions
+
+    if templates_dir is None:
+        templates_dir = os.path.join(hookenv.charm_dir(), 'templates')
+    loader = Environment(loader=FileSystemLoader(templates_dir))
+    try:
+        source = source
+        template = loader.get_template(source)
+    except exceptions.TemplateNotFound as e:
+        hookenv.log('Could not load template %s from %s.' %
+                    (source, templates_dir),
+                    level=hookenv.ERROR)
+        raise e
+    content = template.render(context)
+    host.mkdir(os.path.dirname(target), owner, group, perms=0o755)
+    host.write_file(target, content.encode(encoding), owner, group, perms)

=== added file 'hooks/charmhelpers/core/unitdata.py'
--- hooks/charmhelpers/core/unitdata.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/core/unitdata.py	2015-03-23 00:51:45 +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

=== modified file 'hooks/charmhelpers/fetch/__init__.py'
--- hooks/charmhelpers/fetch/__init__.py	2014-09-08 16:38:59 +0000
+++ hooks/charmhelpers/fetch/__init__.py	2015-03-23 00:51:45 +0000
@@ -1,3 +1,19 @@
+# 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 importlib
 from tempfile import NamedTemporaryFile
 import time
@@ -5,10 +21,6 @@
 from charmhelpers.core.host import (
     lsb_release
 )
-from urlparse import (
-    urlparse,
-    urlunparse,
-)
 import subprocess
 from charmhelpers.core.hookenv import (
     config,
@@ -16,6 +28,12 @@
 )
 import os
 
+import six
+if six.PY3:
+    from urllib.parse import urlparse, urlunparse
+else:
+    from urlparse import urlparse, urlunparse
+
 
 CLOUD_ARCHIVE = """# Ubuntu Cloud Archive
 deb http://ubuntu-cloud.archive.canonical.com/ubuntu {} main
@@ -62,9 +80,16 @@
     'trusty-juno/updates': 'trusty-updates/juno',
     'trusty-updates/juno': 'trusty-updates/juno',
     'juno/proposed': 'trusty-proposed/juno',
-    'juno/proposed': 'trusty-proposed/juno',
     'trusty-juno/proposed': 'trusty-proposed/juno',
     'trusty-proposed/juno': 'trusty-proposed/juno',
+    # Kilo
+    'kilo': 'trusty-updates/kilo',
+    'trusty-kilo': 'trusty-updates/kilo',
+    'trusty-kilo/updates': 'trusty-updates/kilo',
+    'trusty-updates/kilo': 'trusty-updates/kilo',
+    'kilo/proposed': 'trusty-proposed/kilo',
+    'trusty-kilo/proposed': 'trusty-proposed/kilo',
+    'trusty-proposed/kilo': 'trusty-proposed/kilo',
 }
 
 # The order of this list is very important. Handlers should be listed in from
@@ -72,6 +97,7 @@
 FETCH_HANDLERS = (
     'charmhelpers.fetch.archiveurl.ArchiveUrlFetchHandler',
     'charmhelpers.fetch.bzrurl.BzrUrlFetchHandler',
+    'charmhelpers.fetch.giturl.GitUrlFetchHandler',
 )
 
 APT_NO_LOCK = 100  # The return code for "couldn't acquire lock" in APT.
@@ -148,7 +174,7 @@
     cmd = ['apt-get', '--assume-yes']
     cmd.extend(options)
     cmd.append('install')
-    if isinstance(packages, basestring):
+    if isinstance(packages, six.string_types):
         cmd.append(packages)
     else:
         cmd.extend(packages)
@@ -181,7 +207,7 @@
 def apt_purge(packages, fatal=False):
     """Purge one or more packages"""
     cmd = ['apt-get', '--assume-yes', 'purge']
-    if isinstance(packages, basestring):
+    if isinstance(packages, six.string_types):
         cmd.append(packages)
     else:
         cmd.extend(packages)
@@ -192,7 +218,7 @@
 def apt_hold(packages, fatal=False):
     """Hold one or more packages"""
     cmd = ['apt-mark', 'hold']
-    if isinstance(packages, basestring):
+    if isinstance(packages, six.string_types):
         cmd.append(packages)
     else:
         cmd.extend(packages)
@@ -208,7 +234,8 @@
     """Add a package source to this system.
 
     @param source: a URL or sources.list entry, as supported by
-    add-apt-repository(1). Examples:
+    add-apt-repository(1). Examples::
+
         ppa:charmers/example
         deb https://stub:[e-mail]/ubuntu trusty main
 
@@ -217,6 +244,7 @@
         pocket for the release.
         'cloud:' may be used to activate official cloud archive pockets,
         such as 'cloud:icehouse'
+        'distro' may be used as a noop
 
     @param key: A key to be added to the system's APT keyring and used
     to verify the signatures on packages. Ideally, this should be an
@@ -250,12 +278,14 @@
         release = lsb_release()['DISTRIB_CODENAME']
         with open('/etc/apt/sources.list.d/proposed.list', 'w') as apt:
             apt.write(PROPOSED_POCKET.format(release))
+    elif source == 'distro':
+        pass
     else:
-        raise SourceConfigError("Unknown source: {!r}".format(source))
+        log("Unknown source: {!r}".format(source))
 
     if key:
         if '-----BEGIN PGP PUBLIC KEY BLOCK-----' in key:
-            with NamedTemporaryFile() as key_file:
+            with NamedTemporaryFile('w+') as key_file:
                 key_file.write(key)
                 key_file.flush()
                 key_file.seek(0)
@@ -292,14 +322,14 @@
     sources = safe_load((config(sources_var) or '').strip()) or []
     keys = safe_load((config(keys_var) or '').strip()) or None
 
-    if isinstance(sources, basestring):
+    if isinstance(sources, six.string_types):
         sources = [sources]
 
     if keys is None:
         for source in sources:
             add_source(source, None)
     else:
-        if isinstance(keys, basestring):
+        if isinstance(keys, six.string_types):
             keys = [keys]
 
         if len(sources) != len(keys):
@@ -311,22 +341,35 @@
         apt_update(fatal=True)
 
 
-def install_remote(source):
+def install_remote(source, *args, **kwargs):
     """
     Install a file tree from a remote source
 
     The specified source should be a url of the form:
         scheme://[host]/path[#[option=value][&...]]
 
-    Schemes supported are based on this modules submodules
-    Options supported are submodule-specific"""
+    Schemes supported are based on this modules submodules.
+    Options supported are submodule-specific.
+    Additional arguments are passed through to the submodule.
+
+    For example::
+
+        dest = install_remote('http://example.com/archive.tgz',
+                              checksum='deadbeef',
+                              hash_type='sha1')
+
+    This will download `archive.tgz`, validate it using SHA1 and, if
+    the file is ok, extract it and return the directory in which it
+    was extracted.  If the checksum fails, it will raise
+    :class:`charmhelpers.core.host.ChecksumError`.
+    """
     # We ONLY check for True here because can_handle may return a string
     # explaining why it can't handle a given source.
     handlers = [h for h in plugins() if h.can_handle(source) is True]
     installed_to = None
     for handler in handlers:
         try:
-            installed_to = handler.install(source)
+            installed_to = handler.install(source, *args, **kwargs)
         except UnhandledSource:
             pass
     if not installed_to:
@@ -383,7 +426,7 @@
         while result is None or result == APT_NO_LOCK:
             try:
                 result = subprocess.check_call(cmd, env=env)
-            except subprocess.CalledProcessError, e:
+            except subprocess.CalledProcessError as e:
                 retry_count = retry_count + 1
                 if retry_count > APT_NO_LOCK_RETRY_COUNT:
                     raise

=== modified file 'hooks/charmhelpers/fetch/archiveurl.py'
--- hooks/charmhelpers/fetch/archiveurl.py	2014-07-16 05:40:55 +0000
+++ hooks/charmhelpers/fetch/archiveurl.py	2015-03-23 00:51:45 +0000
@@ -1,6 +1,22 @@
+# 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 os
-import urllib2
-import urlparse
+import hashlib
+import re
 
 from charmhelpers.fetch import (
     BaseFetchHandler,
@@ -10,11 +26,54 @@
     get_archive_handler,
     extract,
 )
-from charmhelpers.core.host import mkdir
+from charmhelpers.core.host import mkdir, check_hash
+
+import six
+if six.PY3:
+    from urllib.request import (
+        build_opener, install_opener, urlopen, urlretrieve,
+        HTTPPasswordMgrWithDefaultRealm, HTTPBasicAuthHandler,
+    )
+    from urllib.parse import urlparse, urlunparse, parse_qs
+    from urllib.error import URLError
+else:
+    from urllib import urlretrieve
+    from urllib2 import (
+        build_opener, install_opener, urlopen,
+        HTTPPasswordMgrWithDefaultRealm, HTTPBasicAuthHandler,
+        URLError
+    )
+    from urlparse import urlparse, urlunparse, parse_qs
+
+
+def splituser(host):
+    '''urllib.splituser(), but six's support of this seems broken'''
+    _userprog = re.compile('^(.*)@(.*)$')
+    match = _userprog.match(host)
+    if match:
+        return match.group(1, 2)
+    return None, host
+
+
+def splitpasswd(user):
+    '''urllib.splitpasswd(), but six's support of this is missing'''
+    _passwdprog = re.compile('^([^:]*):(.*)$', re.S)
+    match = _passwdprog.match(user)
+    if match:
+        return match.group(1, 2)
+    return user, None
 
 
 class ArchiveUrlFetchHandler(BaseFetchHandler):
-    """Handler for archives via generic URLs"""
+    """
+    Handler to download archive files from arbitrary URLs.
+
+    Can fetch from http, https, ftp, and file URLs.
+
+    Can install either tarballs (.tar, .tgz, .tbz2, etc) or zip files.
+
+    Installs the contents of the archive in $CHARM_DIR/fetched/.
+    """
     def can_handle(self, source):
         url_parts = self.parse_url(source)
         if url_parts.scheme not in ('http', 'https', 'ftp', 'file'):
@@ -24,22 +83,28 @@
         return False
 
     def download(self, source, dest):
+        """
+        Download an archive file.
+
+        :param str source: URL pointing to an archive file.
+        :param str dest: Local path location to download archive file to.
+        """
         # propogate all exceptions
         # URLError, OSError, etc
-        proto, netloc, path, params, query, fragment = urlparse.urlparse(source)
+        proto, netloc, path, params, query, fragment = urlparse(source)
         if proto in ('http', 'https'):
-            auth, barehost = urllib2.splituser(netloc)
+            auth, barehost = splituser(netloc)
             if auth is not None:
-                source = urlparse.urlunparse((proto, barehost, path, params, query, fragment))
-                username, password = urllib2.splitpasswd(auth)
-                passman = urllib2.HTTPPasswordMgrWithDefaultRealm()
+                source = urlunparse((proto, barehost, path, params, query, fragment))
+                username, password = splitpasswd(auth)
+                passman = HTTPPasswordMgrWithDefaultRealm()
                 # Realm is set to None in add_password to force the username and password
                 # to be used whatever the realm
                 passman.add_password(None, source, username, password)
-                authhandler = urllib2.HTTPBasicAuthHandler(passman)
-                opener = urllib2.build_opener(authhandler)
-                urllib2.install_opener(opener)
-        response = urllib2.urlopen(source)
+                authhandler = HTTPBasicAuthHandler(passman)
+                opener = build_opener(authhandler)
+                install_opener(opener)
+        response = urlopen(source)
         try:
             with open(dest, 'w') as dest_file:
                 dest_file.write(response.read())
@@ -48,16 +113,49 @@
                 os.unlink(dest)
             raise e
 
-    def install(self, source):
+    # Mandatory file validation via Sha1 or MD5 hashing.
+    def download_and_validate(self, url, hashsum, validate="sha1"):
+        tempfile, headers = urlretrieve(url)
+        check_hash(tempfile, hashsum, validate)
+        return tempfile
+
+    def install(self, source, dest=None, checksum=None, hash_type='sha1'):
+        """
+        Download and install an archive file, with optional checksum validation.
+
+        The checksum can also be given on the `source` URL's fragment.
+        For example::
+
+            handler.install('http://example.com/file.tgz#sha1=deadbeef')
+
+        :param str source: URL pointing to an archive file.
+        :param str dest: Local destination path to install to. If not given,
+            installs to `$CHARM_DIR/archives/archive_file_name`.
+        :param str checksum: If given, validate the archive file after download.
+        :param str hash_type: Algorithm used to generate `checksum`.
+            Can be any hash alrgorithm supported by :mod:`hashlib`,
+            such as md5, sha1, sha256, sha512, etc.
+
+        """
         url_parts = self.parse_url(source)
         dest_dir = os.path.join(os.environ.get('CHARM_DIR'), 'fetched')
         if not os.path.exists(dest_dir):
-            mkdir(dest_dir, perms=0755)
+            mkdir(dest_dir, perms=0o755)
         dld_file = os.path.join(dest_dir, os.path.basename(url_parts.path))
         try:
             self.download(source, dld_file)
-        except urllib2.URLError as e:
+        except URLError as e:
             raise UnhandledSource(e.reason)
         except OSError as e:
             raise UnhandledSource(e.strerror)
-        return extract(dld_file)
+        options = parse_qs(url_parts.fragment)
+        for key, value in options.items():
+            if not six.PY3:
+                algorithms = hashlib.algorithms
+            else:
+                algorithms = hashlib.algorithms_available
+            if key in algorithms:
+                check_hash(dld_file, value, key)
+        if checksum:
+            check_hash(dld_file, checksum, hash_type)
+        return extract(dld_file, dest)

=== modified file 'hooks/charmhelpers/fetch/bzrurl.py'
--- hooks/charmhelpers/fetch/bzrurl.py	2014-07-16 05:40:55 +0000
+++ hooks/charmhelpers/fetch/bzrurl.py	2015-03-23 00:51:45 +0000
@@ -1,3 +1,19 @@
+# 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 os
 from charmhelpers.fetch import (
     BaseFetchHandler,
@@ -5,12 +21,18 @@
 )
 from charmhelpers.core.host import mkdir
 
+import six
+if six.PY3:
+    raise ImportError('bzrlib does not support Python3')
+
 try:
     from bzrlib.branch import Branch
+    from bzrlib import bzrdir, workingtree, errors
 except ImportError:
     from charmhelpers.fetch import apt_install
     apt_install("python-bzrlib")
     from bzrlib.branch import Branch
+    from bzrlib import bzrdir, workingtree, errors
 
 
 class BzrUrlFetchHandler(BaseFetchHandler):
@@ -31,8 +53,14 @@
             from bzrlib.plugin import load_plugins
             load_plugins()
         try:
+            local_branch = bzrdir.BzrDir.create_branch_convenience(dest)
+        except errors.AlreadyControlDirError:
+            local_branch = Branch.open(dest)
+        try:
             remote_branch = Branch.open(source)
-            remote_branch.bzrdir.sprout(dest).open_branch()
+            remote_branch.push(local_branch)
+            tree = workingtree.WorkingTree.open(dest)
+            tree.update()
         except Exception as e:
             raise e
 
@@ -42,7 +70,7 @@
         dest_dir = os.path.join(os.environ.get('CHARM_DIR'), "fetched",
                                 branch_name)
         if not os.path.exists(dest_dir):
-            mkdir(dest_dir, perms=0755)
+            mkdir(dest_dir, perms=0o755)
         try:
             self.branch(source, dest_dir)
         except OSError as e:

=== added file 'hooks/charmhelpers/fetch/giturl.py'
--- hooks/charmhelpers/fetch/giturl.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/fetch/giturl.py	2015-03-23 00:51:45 +0000
@@ -0,0 +1,71 @@
+# 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 os
+from charmhelpers.fetch import (
+    BaseFetchHandler,
+    UnhandledSource
+)
+from charmhelpers.core.host import mkdir
+
+import six
+if six.PY3:
+    raise ImportError('GitPython does not support Python 3')
+
+try:
+    from git import Repo
+except ImportError:
+    from charmhelpers.fetch import apt_install
+    apt_install("python-git")
+    from git import Repo
+
+from git.exc import GitCommandError  # noqa E402
+
+
+class GitUrlFetchHandler(BaseFetchHandler):
+    """Handler for git branches via generic and github URLs"""
+    def can_handle(self, source):
+        url_parts = self.parse_url(source)
+        # TODO (mattyw) no support for ssh git@ yet
+        if url_parts.scheme not in ('http', 'https', 'git'):
+            return False
+        else:
+            return True
+
+    def clone(self, source, dest, branch):
+        if not self.can_handle(source):
+            raise UnhandledSource("Cannot handle {}".format(source))
+
+        repo = Repo.clone_from(source, dest)
+        repo.git.checkout(branch)
+
+    def install(self, source, branch="master", dest=None):
+        url_parts = self.parse_url(source)
+        branch_name = url_parts.path.strip("/").split("/")[-1]
+        if dest:
+            dest_dir = os.path.join(dest, branch_name)
+        else:
+            dest_dir = os.path.join(os.environ.get('CHARM_DIR'), "fetched",
+                                    branch_name)
+        if not os.path.exists(dest_dir):
+            mkdir(dest_dir, perms=0o755)
+        try:
+            self.clone(source, dest_dir, branch)
+        except GitCommandError as e:
+            raise UnhandledSource(e.message)
+        except OSError as e:
+            raise UnhandledSource(e.strerror)
+        return dest_dir

=== added symlink 'hooks/nrpe-external-master-relation-changed'
=== target is u'ntp_hooks.py'
=== added symlink 'hooks/nrpe-external-master-relation-joined'
=== target is u'ntp_hooks.py'
=== modified file 'hooks/ntp_hooks.py'
--- hooks/ntp_hooks.py	2014-08-05 05:12:15 +0000
+++ hooks/ntp_hooks.py	2015-03-23 00:51:45 +0000
@@ -9,6 +9,9 @@
 import shutil
 import os
 
+from charmhelpers.contrib.charmsupport import nrpe
+
+NAGIOS_PLUGINS = '/usr/local/lib/nagios/plugins'
 
 NTP_CONF = '/etc/ntp.conf'
 NTP_CONF_ORIG = '{}.orig'.format(NTP_CONF)
@@ -48,6 +51,42 @@
             ntpconf.write(render(os.path.basename(NTP_CONF),
                                  {'servers': remote_sources}))
 
+    update_nrpe_config()
+
+
[e-mail]('nrpe-external-master-relation-joined',
+            'nrpe-external-master-relation-changed')
+def update_nrpe_config():
+    # python-dbus is used by check_upstart_job
+    fetch.apt_install('python-dbus')
+    nagios_ntpmon_checks = hookenv.config('nagios_ntpmon_checks')
+    if os.path.isdir(NAGIOS_PLUGINS):
+        host.rsync(os.path.join(os.getenv('CHARM_DIR'), 'files', 'nagios',
+                   'check_ntpd.pl'),
+                   os.path.join(NAGIOS_PLUGINS, 'check_ntpd.pl'))
+        if nagios_ntpmon_checks:
+            host.rsync(os.path.join(os.getenv('CHARM_DIR'), 'files', 'nagios',
+                       'check_ntpmon.py'),
+                       os.path.join(NAGIOS_PLUGINS, 'check_ntpmon.py'))
+
+    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, ['ntp'], current_unit)
+    nrpe_setup.add_check(
+        shortname="ntp_status",
+        description='Check NTP status {%s}' % current_unit,
+        check_cmd='check_ntpd.pl'
+    )
+    for nc in nagios_ntpmon_checks.split(" "):
+        nrpe_setup.add_check(
+            shortname="ntpmon_%s" % nc,
+            description='Check NTPmon %s {%s}' % (nc, current_unit),
+            check_cmd='check_ntpmon.py --check %s' % nc
+        )
+
+    nrpe_setup.write()
+
 
 if __name__ == '__main__':
     try:

=== modified file 'metadata.yaml'
--- metadata.yaml	2013-09-16 09:14:14 +0000
+++ metadata.yaml	2015-03-23 00:51:45 +0000
@@ -10,8 +10,12 @@
   .
   This charm can be deployed alongside principle charms to enable NTP
   management across deployed services.
-categories:
+tags:
     - misc
+provides:
+  nrpe-external-master:
+    interface: nrpe-external-master
+    scope: container
 requires:
   juju-info:
     interface: juju-info