Merge lp:~hloeung/jenkins-agent-charm/reactive-rewrite into lp:jenkins-agent-charm

[Haw Loeung]

Charm rewrite using Python and the Reactive framework

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

This merge proposal is being monitored by mergebot. Change the status to Approved to merge.

[Tom Haddon (mthaddon)]

Some comments and questions inline.

review: Needs Fixing

[Tom Haddon (mthaddon)]

Missed one other thing as well.

[Tom Haddon (mthaddon)]

Some comments inline with suggestions for testing.

[Tom Haddon (mthaddon)]

Er, we we obviously *do* want the max-complexity check

[Tom Haddon (mthaddon)]

A few comments inline

[Haw Loeung (hloeung)]

review: Needs Resubmitting

[lp:~hloeung/jenkins-agent-charm/reactive-rewrite]

50. By Haw Loeung on 2019-03-01

Added basic functional test

51. By Haw Loeung on 2019-03-01

Fixed to use the module itself instead of sys.modules

[Tom Haddon (mthaddon)]

LGTM, thanks

review: Approve

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

Change successfully merged at revision 22

=== added file '.bzrignore'
--- .bzrignore	1970-01-01 00:00:00 +0000
+++ .bzrignore	2019-03-01 05:39:53 +0000
@@ -0,0 +1,11 @@
+*.pyc
+*.swp
+*~
+.coverage
+.pytest_cache/
+.tox/
+.unit-state.db
+__pycache__/
+builds/
+deps/
+revision
 
=== added file 'Makefile'
--- Makefile	1970-01-01 00:00:00 +0000
+++ Makefile	2019-03-01 05:39:53 +0000
@@ -0,0 +1,30 @@
+help:
+	@echo "This project supports the following targets"
+	@echo ""
+	@echo " make help - show this text"
+	@echo " make lint - run flake8"
+	@echo " make test - run the functional test and unittests"
+	@echo " make unittest - run the the unittest"
+	@echo " make functionaltest - run the functional tests"
+	@echo " make clean - remove unneeded files"
+	@echo ""
+
+lint:
+	@echo "Running flake8"
+	@tox -e lint
+
+test: unittest functionaltest lint
+
+unittest:
+	@tox -e unit
+
+functionaltest:
+	@tox -e functional
+
+clean:
+	@echo "Cleaning files"
+	@if [ -d ./.tox ] ; then rm -r ./.tox ; fi
+	@if [ -d ./.pytest_cache ] ; then rm -r ./.pytest_cache ; fi
+
+# The targets below don't depend on a file
+.PHONY: lint test unittest functionaltest clean help
 
=== modified file 'README.md'
--- README.md	2014-05-15 16:06:29 +0000
+++ README.md	2019-03-01 05:39:53 +0000
@@ -21,3 +21,8 @@
     juju deploy --to <special-mabine-number> jenkins-slave ppc-slave
 
 See the Jenkins charm for more details.
+
+
+# Notes
+
+We can't use interface:jenkins-slave yet as it's not fully implemented.
 
=== added directory 'actions'
=== added file 'files/jenkins-slave-sudoers'
--- files/jenkins-slave-sudoers	1970-01-01 00:00:00 +0000
+++ files/jenkins-slave-sudoers	2019-03-01 05:39:53 +0000
@@ -0,0 +1,5 @@
+# Created automatically during charm installation
+# Any manual changes to it will be lost
+
+# User rules for jenkins
+jenkins ALL=(ALL) NOPASSWD: ALL
 
=== removed symlink 'hooks/config-changed'
=== target was u'install'
=== removed file 'hooks/configure-slave'
--- hooks/configure-slave	2016-06-03 02:54:52 +0000
+++ hooks/configure-slave	1970-01-01 00:00:00 +0000
@@ -1,27 +0,0 @@
-#!/bin/bash
-
-set -e
-
-# Grab the jenkins master url as a passed in parameter
-url="$1"
-
-# Set the slave hostname to match the juju unit
-slavehost="$(echo ${JUJU_UNIT_NAME} | sed s,/,-,)"
-
-# Set the slave and url fields
-juju-log "Configuring jenkins-slave with ${url}..."
-sed -i -e "s!^JENKINS_HOSTNAME.*!JENKINS_HOSTNAME=${slavehost}!" \
-       -e "s!^#*JENKINS_URL.*!JENKINS_URL=${url}!" \
-        /etc/default/jenkins-slave
-
-# Startup the jenkins-slave service
-# This is called in the install, config-changed and upgrade-charm paths
-# It needs to be tolerant of a running or stopped jenkins-slave
-status="$(service jenkins-slave status || true)"
-if echo "${status}" | egrep -q "stop|inactive"; then
-    juju-log "Starting jenkins-slave..."
-    service jenkins-slave start 
-else
-    juju-log "Restarting jenkins-slave..."
-    service jenkins-slave restart
-fi
 
=== removed symlink 'hooks/install.d/03_nrpe_relation_changed'
=== target was u'canonical_ci_utils.py'
=== removed file 'hooks/install.d/add_sudoers'
--- hooks/install.d/add_sudoers	2015-08-13 18:04:16 +0000
+++ hooks/install.d/add_sudoers	1970-01-01 00:00:00 +0000
@@ -1,18 +0,0 @@
-#!/bin/bash
-
-set -eu
-
-temp_sudoers="$(mktemp /tmp/jenkins.XXXXXX)"
-
-cat > "$temp_sudoers" << EOF
-# Created automatically during charm installation
-# Any manual changes to it will be lost
-
-# User rules for jenkins
-jenkins ALL=(ALL) NOPASSWD: ALL
-EOF
-
-visudo -c -f "$temp_sudoers"
-install -m 440 "$temp_sudoers" /etc/sudoers.d/jenkins
-rm "$temp_sudoers"
-visudo -c
 
=== removed file 'hooks/install.d/canonical_ci_utils.py'
--- hooks/install.d/canonical_ci_utils.py	2015-12-03 10:40:55 +0000
+++ hooks/install.d/canonical_ci_utils.py	1970-01-01 00:00:00 +0000
@@ -1,91 +0,0 @@
-#!/usr/bin/python
-
-import os
-import sys
-
-from charmhelpers.canonical_ci import nrpe
-
-
-from charmhelpers.core.hookenv import (
-    config,
-    local_unit,
-    log,
-    relation_ids,
-    unit_get,
-    ERROR,
-    INFO,
-)
-
-from charmhelpers.core.host import (
-    service_reload,
-)
-
-# Constants set in jenkins/hooks/install.
-JENKINS_HOME = '/var/lib/jenkins'
-JENKINS_USER = 'jenkins'
-JENKINS_GROUP = 'nogroup'
-JENKINS_PORT = 8080
-
-# Local constants
-NRPE_CHECK_PS = "/etc/nagios/nrpe.d/check_jenkins_slave_ps.cfg"
-
-
-def update_nrpe_config():
-    if not relation_ids('nrpe-external-master'):
-        log('No relation to an nrpe-external-master, not configuring '
-            'nagios.')
-        return
-    with open(NRPE_CHECK_PS, "w") as conf:
-        log("Writing config: %s." % NRPE_CHECK_PS, INFO)
-        conf.write(nrpe.CONF_HEADER)
-        conf.write(
-            "command[check_jenkins_slave_ps]="
-            "/usr/lib/nagios/plugins/check_procs -c 1:1 -a slave.jar")
-
-    # config
-    unit_name = local_unit().replace('/', '-')
-    n_hostname = "%s-%s" % (config("nagios_context"), unit_name)
-    n_servicegroup = config("nagios_servicegroups") if config("nagios_servicegroups") else config("nagios_context")
-    service_file = (
-        '/var/lib/nagios/export/service__%s_check_jenkins_slave.cfg' %
-        n_hostname)
-
-    # There is a race between this code and the nrpe_external_master install
-    # hook. Both need to write files to /var/lib/nagios/export, but only one
-    # needs to create it. So tolerate failure if the directory exists.
-    try:
-        os.makedirs(os.path.dirname(service_file))
-    except os.error:
-        pass
-
-    with open(service_file, "w") as conf:
-        log("Writing config: %s." % conf, INFO)
-        conf.write(nrpe.CONF_HEADER)
-        conf.write(nrpe.NRPE_SERVICE_ENTRY % {
-            'nagios_hostname': n_hostname,
-            'check_name': 'check_jenkins_slave_ps',
-            'nagios_servicegroup': n_servicegroup,
-        })
-
-    # reboot
-    if os.path.isfile('/etc/init.d/nagios-nrpe-server'):
-        service_reload('nagios-nrpe-server')
-
-
-hooks = {
-    '03_nrpe_relation_changed': update_nrpe_config
-}
-
-
-def main(hook):
-    try:
-        hooks[hook]()
-    except KeyError:
-        e = 'Invalid install.d hook: %s.' % hook
-        log(e, ERROR)
-        raise Exception(e)
-
-
-if __name__ == '__main__':
-    if os.path.islink(sys.argv[0]):
-        main(os.path.basename(sys.argv[0]))
 
=== removed file 'hooks/nrpe-external-master-relation-changed'
--- hooks/nrpe-external-master-relation-changed	2015-08-19 20:00:15 +0000
+++ hooks/nrpe-external-master-relation-changed	1970-01-01 00:00:00 +0000
@@ -1,7 +0,0 @@
-#!/bin/sh
-set -e
-
-home=`dirname $0`
-
-juju-log "Running install hook once more to pick up new NRPE relation changes"
-exec $home/install
 
=== removed symlink 'hooks/slave-relation-broken'
=== target was u'slave-relation-departed'
=== removed file 'hooks/slave-relation-changed'
--- hooks/slave-relation-changed	2015-08-05 13:20:44 +0000
+++ hooks/slave-relation-changed	1970-01-01 00:00:00 +0000
@@ -1,19 +0,0 @@
-#!/bin/bash
-
-set -e
-
-# Setup connection to master instance once set
-url="$(relation-get url)"
-
-if [ "x$url" = "x" ]; then
-	juju-log "Master hasn't exported its url yet, exiting..."
-	exit 0
-fi
-
-master_url="$(config-get master_url)"
-if [ -n "${master_url}" ]; then
-	juju-log "Config option 'master_url' is set. Can't use slave relation."
-	exit 0
-fi
-
-hooks/configure-slave "${url}"
 
=== removed file 'hooks/slave-relation-departed'
--- hooks/slave-relation-departed	2012-07-27 11:23:24 +0000
+++ hooks/slave-relation-departed	1970-01-01 00:00:00 +0000
@@ -1,3 +0,0 @@
-#!/bin/bash
-
-stop jenkins-slave || true
 
=== removed file 'hooks/slave-relation-joined'
--- hooks/slave-relation-joined	2015-08-04 16:46:21 +0000
+++ hooks/slave-relation-joined	1970-01-01 00:00:00 +0000
@@ -1,20 +0,0 @@
-#!/bin/bash
-
-set -e
-
-# Set the slave hostname to match the juju unit
-# in the jenkins master instance
-slavehost=`echo ${JUJU_UNIT_NAME} | sed s,/,-,`
-noexecutors=`cat /proc/cpuinfo | grep processor | wc -l`
-config_labels=`config-get labels`
-labels=`uname -p`
-
-if [ -n "$config_labels" ]; then
-    labels=$config_labels
-fi
-
-# Set all relations
-relation-set executors=$noexecutors
-relation-set labels="$labels"
-relation-set slavehost=$slavehost
-relation-set slaveaddress=`unit-get private-address`
 
=== removed file 'hooks/start'
--- hooks/start	2011-08-02 08:53:54 +0000
+++ hooks/start	1970-01-01 00:00:00 +0000
@@ -1,3 +0,0 @@
-#!/bin/bash
-
-start jenkins-slave || true
 
=== removed file 'hooks/stop'
--- hooks/stop	2011-08-02 08:53:54 +0000
+++ hooks/stop	1970-01-01 00:00:00 +0000
@@ -1,3 +0,0 @@
-#!/bin/bash
-
-stop jenkins-slave
 
=== removed symlink 'hooks/upgrade-charm'
=== target was u'install'
=== added file 'layer.yaml'
--- layer.yaml	1970-01-01 00:00:00 +0000
+++ layer.yaml	2019-03-01 05:39:53 +0000
@@ -0,0 +1,5 @@
+includes:
+  - layer:basic
+  - layer:apt
+  - layer:nagios
+repo: lp:jenkins-slave-charm
 
=== added directory 'lib'
=== modified file 'metadata.yaml'
--- metadata.yaml	2019-02-18 00:41:09 +0000
+++ metadata.yaml	2019-03-01 05:39:53 +0000
@@ -9,8 +9,12 @@
   This charm provides support for jenkins slaves
   .
   https://launchpad.net/jenkins-slave-charm
-categories:
+tags:
   - applications
+series:
+  - bionic
+  - xenial
+  - trusty
 provides:
   slave:
     interface: jenkins-slave
 
=== added directory 'reactive'
=== renamed file 'hooks/install' => 'reactive/jenkins_slave.py'
--- hooks/install	2016-06-14 01:04:43 +0000
+++ reactive/jenkins_slave.py	2019-03-01 05:39:53 +0000
@@ -1,121 +1,231 @@
-#!/bin/bash
-
-set -eu
-
-
-install_exec_d () {
-    if [[ -d exec.d ]]; then
-	 shopt -s nullglob
-	 for f in exec.d/*/charm-pre-install; do
-	     [[ -x "$f" ]] || continue
-	     ${SHELL} -c "$f"|| {
-		  ## bail out if anyone fails
-		  juju-log -l ERROR "$f: returned exit_status=$? "
-	     }
-	 done
-	 shopt -u nullglob
-    fi
-}
-
-# Get rid of the legacy jenkins-slave package, including config files.
-clean_up_old_package () {
-    juju-log "Removing the old jenkin-slave package... (obsoleted by this charm)"
-    dpkg --purge jenkins-slave
-    juju-log "Removing the old jenkin-slave package... done."
-}
-
-# Install the slave if it is not installed already.
-install_slave () {
-    juju-log "Installing jenkins-slave..."
-    juju-log "Installing jenkins-slave (dependencies)..."
-    apt-get -y install -qq wget adduser default-jre-headless
+import os
+
+from charmhelpers.core import hookenv, host, templating, unitdata
+from charmhelpers.contrib.charmsupport import nrpe
+from charmhelpers.fetch import apt_purge
+from charms import apt, reactive
+
+
[e-mail]('upgrade-charm')
+def upgrade_charm():
+    hookenv.status_set('maintenance', 'forcing reconfiguration on upgrade-charm')
+    reactive.clear_flag('jenkins-slave.active')
+    reactive.clear_flag('jenkins-slave.installed')
+
+
[e-mail]_not('jenkins-slave.installed')
+def install():
+    hookenv.status_set('maintenance', 'installing jenkins-slave')
+    reactive.clear_flag('jenkins-slave.active')
+
+    config = hookenv.config()
+
+    hookenv.log('Adding jenkins-slave dependencies to be installed')
+    packages = ['wget', 'default-jre-headless']
+
+    # Install extra packages needed by the slave.
+    tools = config.get('tools')
+    if tools:
+        hookenv.log('Adding jenkins-slave additional tools to be installed: {}'.format(tools))
+        for package in tools.split():
+            packages.append(package)
+    apt.queue_install(packages)
+    if not apt.install_queued():
+        return  # apt layer already set blocked state.
+
+    # Get rid of the legacy jenkins-slave package, including config files.
+    hookenv.log('Removing the old jenkins-slave package... (obsoleted by this charm)')
+    apt_purge(['jenkins-slave'])
 
     # Create jenkins user if it doesn't exist.
-    if ! id jenkins > /dev/null 2>&1 ; then
-	juju-log "Installing jenkins-slave (user account)..."
-        adduser --system --home /var/lib/jenkins --group \
-	    --disabled-password --quiet --shell /bin/bash \
-            jenkins 
-    else
-	juju-log "Installing jenkins-slave (user account already exists)..."
-    fi
-    juju-log "Installing jenkins-slave (directories)..."
+    if host.user_exists('jenkins'):
+        hookenv.log('Installing jenkins-slave (user account already exists)...')
+    else:
+        hookenv.log('Installing jenkins-slave (user account)...')
+        host.adduser(username='jenkins', system_user=True, home_dir='/var/lib/jenkins')
+
     # And ensure required directories exist and are set up.
-    mkdir -p /var/lib/jenkins
-    chown -R jenkins:jenkins /var/lib/jenkins || true
-    mkdir -p /var/log/jenkins
-    chown -R jenkins:jenkins /var/log/jenkins || true
-    juju-log "Installing jenkins-slave (common files)..."
-    install -m 0555 files/download-slave.sh /usr/local/sbin/download-slave.sh
-    # XXX obviously we lose conffile handling here...
-    install -m 0444 files/jenkins-slave-default /etc/default/jenkins-slave
-    install -m 0444 files/jenkins-slave-logrotate-config /etc/logrotate.d/jenkins-slave
-
-    distro=$(source /etc/lsb-release ; echo $DISTRIB_CODENAME)
-    case $distro in
-	xenial)
-	    # LTS or bust!
-	    juju-log "Installing jenkins-slave (system unit)..."
-	    install -m 0444 files/jenkins-slave-systemd-config /lib/systemd/system/jenkins-slave.service
-	    systemctl enable jenkins-slave
-	    ;;
-        *)
-	    # Probably an LTS, and it's not, then too bad.
-	    juju-log "Installing jenkins-slave (upstart job)..."
-            install -m 0444 files/jenkins-slave-upstart-config /etc/init/jenkins-slave.conf
-	    ;;
-     esac
-    juju-log "Installing jenkins-slave... done."
-}
-
-
-# Install extra packages needed by the slave.
-install_tools () {
-    juju-log "Installing tools..."
-    apt-get -y install -qq $(config-get tools)
-}
-
-
-# Configure slave
-set_up_slave () {
-    # If a master_url value is specified, use that to configure the slave.
-    master_url="$(config-get master_url)"
-    if [ -n "${master_url}" ]; then
-        juju-log "Using 'master_url' to configure the slave."
-        hooks/configure-slave "${master_url}"
-    else
-        juju-log "No 'master_url' set; not configuring slave at this time."
-    fi
-}
-
-# Execute any hook overlay which may be provided
-# by forks of this charm.
-install_extra_hooks () {
-    # XXX for canonical_ci_utils.py
-    apt-get -y install -qq python-yaml
-
-    juju-log "Installing hooks..."
-    if [[ -d hooks/install.d ]]
-    then
-        for i in $(ls -1 hooks/install.d/*)
-        do
-            if [[ -x "$i" ]]
-            then
-                ./$i
-            fi
-        done
-    else
-        juju-log "No extra hooks found."
-    fi
-}
-
-
-apt-get update -qq
-install_exec_d
-clean_up_old_package
-install_slave
-install_tools
-set_up_slave
-install_extra_hooks
-
-exit 0
+    hookenv.log('Installing jenkins-slave (directories)...')
+    host.mkdir('/var/lib/jenkins', owner='jenkins', group='jenkins')
+    host.mkdir('/var/log/jenkins', owner='jenkins', group='jenkins')
+
+    hookenv.log('Installing jenkins-slave (common files)...')
+    write_default_conf()
+    file_to_units('files/download-slave.sh', '/usr/local/sbin/download-slave.sh')
+    file_to_units('files/jenkins-slave-logrotate-config', '/etc/logrotate.d/jenkins-slave')
+
+    if host.lsb_release()['DISTRIB_CODENAME'] == 'trusty':
+        hookenv.log('Installing jenkins-slave (upstart job)...')
+        file_to_units('files/jenkins-slave-upstart-config', '/etc/init/jenkins-slave.conf')
+    else:
+        hookenv.log('Installing jenkins-slave (system unit)...')
+        file_to_units('files/jenkins-slave-systemd-config', '/lib/systemd/system/jenkins-slave.service')
+        host.service('enable', 'jenkins-slave')
+
+    hookenv.log('Installing jenkins-slave... done.')
+    reactive.clear_flag('jenkins-slave.blocked')
+    reactive.clear_flag('jenkins-slave.configured')
+    reactive.set_flag('jenkins-slave.installed')
+
+
[e-mail]('config.changed')
+def config_changed():
+    reactive.clear_flag('jenkins-slave.blocked')
+    reactive.clear_flag('jenkins-slave.configured')
+    reactive.clear_flag('nagios-nrpe.configured')
+
+
[e-mail]('jenkins-slave.installed')
[e-mail]_not('jenkins-slave.configured')
[e-mail]_not('jenkins-slave.blocked')
+def configure_jenkins_slave():
+    hookenv.status_set('maintenance', 'configuring jenkins-slave')
+    reactive.clear_flag('jenkins-slave.active')
+
+    config = hookenv.config()
+    kv = unitdata.kv()
+
+    if config.get('master_url'):
+        hookenv.log("Using 'master_url' to configure the slave.")
+        write_default_conf(config.get('master_url'))
+    elif kv.get('url'):
+        hookenv.log("Using url from relation as 'master_url'")
+        write_default_conf(kv.get('url'))
+    else:
+        hookenv.log("No 'master_url' set; not configuring slave at this time.")
+        hookenv.status_set('blocked', "requires either slave relation or 'master_url'")
+        reactive.set_flag('jenkins-slave.blocked')
+        return
+
+    file_to_units('files/jenkins-slave-sudoers', '/etc/sudoers.d/jenkins', perms=0o440)
+
+    reactive.clear_flag('nagios-nrpe.configured')
+    reactive.set_flag('jenkins-slave.configured')
+
+
[e-mail]('jenkins-slave.blocked')
+def blocked_on_jenkins_url():
+    reactive.clear_flag('jenkins-slave.active')
+
+
[e-mail]('jenkins-slave.configured')
[e-mail]('nrpe-external-master.available')
[e-mail]('jenkins-slave.active')
[e-mail]_not('nagios-nrpe.configured')
+def configure_nagios(nagios):
+    hookenv.status_set('maintenance', 'setting up NRPE checks')
+
+    # Use charmhelpers.contrib.charmsupport's nrpe to determine hostname
+    hostname = nrpe.get_nagios_hostname()
+    nrpe_setup = nrpe.NRPE(hostname=hostname, primary=True)
+
+    cmd = '/usr/lib/nagios/plugins/check_procs -c 1:1 -a slave.jar'
+    nrpe_setup.add_check('jenkins_slave_ps', 'Jenkins Slave Process', cmd)
+
+    nrpe_setup.write()
+    reactive.set_flag('nagios-nrpe.configured')
+
+
[e-mail]('jenkins-slave.configured')
[e-mail]_not('jenkins-slave.active')
+def set_active():
+    # Startup the jenkins-slave service. This is called in the
+    # install, config-changed and upgrade-charm paths. It needs to be
+    # tolerant of a running or stopped jenkins-slave.
+    if host.service_running('jenkins-slave'):
+        hookenv.log('Restarting jenkins-slave...')
+        host.service_restart('jenkins-slave')
+    else:
+        hookenv.log('Starting jenkins-slave...')
+        host.service_start('jenkins-slave')
+
+    hookenv.status_set('active', 'ready')
+    reactive.set_flag('jenkins-slave.active')
+
+
+# We can't use interface:jenkins-slave yet as it's not implemented.
[e-mail]('slave-relation-joined', 'slave-relation-changed')
+def slave_relation_changed():
+    reactive.set_flag('slave-relation.available')
+    reactive.clear_flag('jenkins-slave.blocked')
+    reactive.clear_flag('jenkins-slave.configured')
+    reactive.clear_flag('slave-relation.configured')
+
+
[e-mail]('slave-relation-departed', 'slave-relation-broken')
+def slave_relation_removed():
+    kv = unitdata.kv()
+    kv.set('url', None)
+    reactive.clear_flag('slave-relation.available')
+
+
[e-mail]('slave-relation.available')
[e-mail]_not('slave-relation.configured')
+def slave_relation():
+    hookenv.status_set('maintenance', 'setting up jenkins via slave relation')
+    config = hookenv.config()
+    kv = unitdata.kv()
+
+    if config.get('master_url'):
+        hookenv.log("Config option 'master_url' is set. Can't use slave relation.")
+        reactive.set_flag('slave-relation.configured')
+        return
+
+    url = hookenv.relation_get('url')
+    if url:
+        kv.set('url', url)
+        write_default_conf(url)
+    else:
+        hookenv.log("Master hasn't exported its url yet, exiting...")
+        return
+
+    reactive.clear_flag('jenkins-slave.active')
+
+    # Set the slave hostname to match the juju unit
+    # in the jenkins master instance
+    slave_host = hookenv.local_unit().replace('/', '-')
+    slave_address = hookenv.unit_private_ip()
+    noexecutors = os.cpu_count()
+    config_labels = config.get('labels')
+
+    if config_labels:
+        labels = config_labels
+    else:
+        labels = os.uname()[4]
+
+    # Set all relations
+    hookenv.relation_set(executors=noexecutors)
+    hookenv.relation_set(labels=labels)
+    hookenv.relation_set(slavehost=slave_host)
+    hookenv.relation_set(slaveaddress=slave_address)
+    reactive.set_flag('slave-relation.configured')
+
+
+def file_to_units(local_path, unit_path, perms=None, owner='root', group='root'):
+    """ copy a file from the charm onto our unit(s) """
+    file_perms = perms
+    if not perms:
+        # Let's try manually work it out
+        if local_path[-3:] == '.py' or local_path[-3:] == '.sh':
+            file_perms = 0o755
+        else:
+            file_perms = 0o644
+
+    with open(local_path, 'r') as fh:
+        host.write_file(
+            path=unit_path,
+            content=fh.read().encode(),
+            owner=owner,
+            group=group,
+            perms=file_perms,
+        )
+
+
+def write_default_conf(master_url=None, owner='root', group='root',
+                       conf_path='/etc/default/jenkins-slave'):
+    templates_dir = os.path.join(hookenv.charm_dir(), 'templates')
+    slave_host = hookenv.local_unit().replace('/', '-')
+    templating.render('jenkins-slave-default', conf_path,
+                      {'master_url': master_url, 'slave_host': slave_host},
+                      owner=owner, group=group, perms=0o444,
+                      templates_dir=templates_dir)
 
=== added file 'requirements.txt'
--- requirements.txt	1970-01-01 00:00:00 +0000
+++ requirements.txt	2019-03-01 05:39:53 +0000
@@ -0,0 +1,1 @@
+# Include python requirements here
 
=== removed file 'revision'
--- revision	2015-08-04 16:46:21 +0000
+++ revision	1970-01-01 00:00:00 +0000
@@ -1,1 +0,0 @@
-9
 
=== added directory 'templates'
=== renamed file 'files/jenkins-slave-default' => 'templates/jenkins-slave-default'
--- files/jenkins-slave-default	2016-06-03 03:37:31 +0000
+++ templates/jenkins-slave-default	2019-03-01 05:39:53 +0000
@@ -32,12 +32,20 @@
 # URL of jenkins server to connect to 
 # Not specifying this parameter will stop the slave 
 # job from running.
+{% if master_url %}
+JENKINS_URL="{{ master_url }}"
+{% else %}
 #JENKINS_URL=""
+{% endif %}
 
 # Name of slave configuration to use at JENKINS_URL
 # Override if it need to be something other than the
 # hostname of the server the slave is running on.
+{% if slave_host %}
+JENKINS_HOSTNAME="{{ slave_host }}"
+{% else %}
 JENKINS_HOSTNAME="$(hostname)"
+{% endif %}
 
 # Log file location for use in Debian init script
 JENKINS_SLAVE_LOG=/var/log/jenkins/$NAME.log
 
=== added directory 'tests'
=== added directory 'tests/functional'
=== added file 'tests/functional/requirements.txt'
--- tests/functional/requirements.txt	1970-01-01 00:00:00 +0000
+++ tests/functional/requirements.txt	2019-03-01 05:39:53 +0000
@@ -0,0 +1,6 @@
+flake8
+juju
+mock
+pytest
+pytest-asyncio
+requests
 
=== added file 'tests/functional/test_jenkins_slave.py'
--- tests/functional/test_jenkins_slave.py	1970-01-01 00:00:00 +0000
+++ tests/functional/test_jenkins_slave.py	2019-03-01 05:39:53 +0000
@@ -0,0 +1,50 @@
+import os
+import pytest
+from juju.model import Model
+
+# Treat tests as coroutines
+pytestmark = pytest.mark.asyncio
+
+series = ['bionic']
+juju_repository = os.getenv('JUJU_REPOSITORY', '.').rstrip('/')
+
+
[e-mail]
+async def model():
+    model = Model()
+    await model.connect_current()
+    yield model
+    await model.disconnect()
+
+
[e-mail]
+async def apps(model):
+    apps = []
+    for entry in series:
+        app = model.applications['jenkins-slave-{}'.format(entry)]
+        apps.append(app)
+    return apps
+
+
[e-mail]
+async def units(apps):
+    units = []
+    for app in apps:
+        units.extend(app.units)
+    return units
+
+
[e-mail]('series', series)
+async def test_jenkins_slave_deploy(model, series):
+    # Starts a deploy for each series
+    await model.deploy('{}/builds/jenkins-slave'.format(juju_repository),
+                       series=series,
+                       application_name='jenkins-slave-{}'.format(series))
+    assert True
+
+
+async def test_jenkins_slave_status(apps, model):
+    # Verifies status for all deployed series of the charm
+    for app in apps:
+        await model.block_until(lambda: app.status == 'active')
+    assert True
 
=== added directory 'tests/unit'
=== added directory 'tests/unit/files'
=== added file 'tests/unit/files/jenkins-slave-default'
--- tests/unit/files/jenkins-slave-default	1970-01-01 00:00:00 +0000
+++ tests/unit/files/jenkins-slave-default	2019-03-01 05:39:53 +0000
@@ -0,0 +1,59 @@
+#
+# This file is managed by Juju.  Attempt no changes here.
+#
+
+# defaults for jenkins-slave component of the jenkins continuous integration 
+# system
+
+# pulled in from the init script; makes things easier.
+NAME=jenkins-slave
+
+# location of java
+JAVA=/usr/bin/java
+
+# arguments to pass to java - optional
+#JAVA_ARGS="-Xmx256m"
+
+# for daemon to use
+PIDFILE=/var/run/jenkins/$NAME.pid
+
+# user id to be invoked as (otherwise will run as root; not wise!)
+JENKINS_USER=jenkins
+
+# location of jenkins arch indep files
+JENKINS_ROOT=/usr/share/jenkins
+
+# jenkins home location
+JENKINS_HOME=/var/lib/jenkins
+
+# jenkins /run location
+JENKINS_RUN=/var/run/jenkins
+
+# URL of jenkins server to connect to 
+# Not specifying this parameter will stop the slave 
+# job from running.
+
+#JENKINS_URL=""
+
+
+# Name of slave configuration to use at JENKINS_URL
+# Override if it need to be something other than the
+# hostname of the server the slave is running on.
+
+JENKINS_HOSTNAME="jenkins-slave-3"
+
+
+# Log file location for use in Debian init script
+JENKINS_SLAVE_LOG=/var/log/jenkins/$NAME.log
+
+# OS LIMITS SETUP
+#   comment this out to observe /etc/security/limits.conf
+#   this is on by default because http://github.com/feniix/hudson/commit/d13c08ea8f5a3fa730ba174305e6429b74853927
+#   reported that Ubuntu's PAM configuration doesn't include pam_limits.so, and as a result the # of file
+#   descriptors are forced to 1024 regardless of /etc/security/limits.confa
+# NOTE - Ubuntu Users - this is not used by the upstart configuration - please use an upstart overrides file
+# to change the OS limits setup.
+MAXOPENFILES=8192
+
+# Arguments to pass to jenkins slave on startup
+JENKINS_ARGS="-jnlpUrl $JENKINS_URL/computer/$JENKINS_HOSTNAME/slave-agent.jnlp"
 \ No newline at end of file
 
=== added file 'tests/unit/files/somefile'
=== added file 'tests/unit/files/somefile.py'
=== added file 'tests/unit/requirements.txt'
--- tests/unit/requirements.txt	1970-01-01 00:00:00 +0000
+++ tests/unit/requirements.txt	2019-03-01 05:39:53 +0000
@@ -0,0 +1,5 @@
+charmhelpers
+charms.reactive
+mock
+pytest
+pytest-cov
 
=== added file 'tests/unit/test_jenkins_slave.py'
--- tests/unit/test_jenkins_slave.py	1970-01-01 00:00:00 +0000
+++ tests/unit/test_jenkins_slave.py	2019-03-01 05:39:53 +0000
@@ -0,0 +1,218 @@
+import grp
+import os
+import pwd
+import shutil
+import sys
+import tempfile
+import unittest
+from unittest import mock
+
+sys.modules['charms.apt'] = mock.MagicMock()
+from charms import apt  # NOQA: E402
+
+# Add path to where our reactive layer lives and import.
+sys.path.append(os.path.dirname(os.path.dirname(os.path.dirname(os.path.realpath(__file__)))))
+from reactive.jenkins_slave import (
+    config_changed,
+    install,
+    configure_jenkins_slave,
+    file_to_units,
+    write_default_conf,
+)  # NOQA: E402
+
+
+INITIAL_CONF = 'tests/unit/files/jenkins-slave-default'
+
+
+class TestSetDefaultConf(unittest.TestCase):
+    def setUp(self):
+        self.tmpdir = tempfile.mkdtemp(prefix='charm-unittests-')
+        temp_file = tempfile.NamedTemporaryFile(delete=False, dir=self.tmpdir)
+        with open(INITIAL_CONF, 'rb') as f:
+            conf = f.read().decode('utf-8')
+        temp_file.write(conf.encode())
+        temp_file.close()
+        self.conf_file = temp_file.name
+        self.user = pwd.getpwuid(os.getuid()).pw_name
+        self.group = grp.getgrgid(os.getgid()).gr_name
+        self.charm_dir = os.path.dirname(os.path.dirname(os.path.dirname(os.path.realpath(__file__))))
+
+        # charmhelpers is getting difficult to test against, as it writes
+        # to system directories even for things that should be idempotent,
+        # like accessing config options.
+        patcher = mock.patch('charmhelpers.core.hookenv.charm_dir')
+        self.mock_charm_dir = patcher.start()
+        self.addCleanup(patcher.stop)
+        self.mock_charm_dir.return_value = self.charm_dir
+
+        patcher = mock.patch('charmhelpers.core.hookenv.config')
+        self.mock_config = patcher.start()
+        self.addCleanup(patcher.stop)
+        self.mock_config.return_value = {'tools': []}
+
+        patcher = mock.patch('charmhelpers.core.hookenv.local_unit')
+        self.mock_local_unit = patcher.start()
+        self.addCleanup(patcher.stop)
+        self.mock_local_unit.return_value = 'mock-jenkins-slave/0'
+
+        patcher = mock.patch('charmhelpers.core.hookenv.log')
+        self.mock_log = patcher.start()
+        self.addCleanup(patcher.stop)
+        self.mock_log.return_value = ''
+
+    def tearDown(self):
+        shutil.rmtree(self.tmpdir)
+
+    @mock.patch('charms.reactive.clear_flag')
+    def test_hook_config_changed(self, clear_flag):
+        config_changed()
+        expected = [mock.call('jenkins-slave.blocked'),
+                    mock.call('jenkins-slave.configured'),
+                    mock.call('nagios-nrpe.configured')]
+        self.assertEqual(clear_flag.call_args_list, expected)
+
+    @mock.patch('charmhelpers.core.host.adduser')
+    @mock.patch('charmhelpers.core.host.mkdir')
+    @mock.patch('charmhelpers.core.host.service')
+    @mock.patch('reactive.jenkins_slave.apt_purge')
+    @mock.patch('reactive.jenkins_slave.file_to_units')
+    @mock.patch('reactive.jenkins_slave.write_default_conf')
+    def test_hook_install(self, write_default_conf, file_to_units, apt_purge, service, mkdir, adduser):
+        install()
+        expected = [mock.call(home_dir='/var/lib/jenkins', system_user=True, username='jenkins')]
+        self.assertEqual(adduser.call_args_list, expected)
+        expected = [mock.call('/var/lib/jenkins', group='jenkins', owner='jenkins'),
+                    mock.call('/var/log/jenkins', group='jenkins', owner='jenkins')]
+        self.assertEqual(mkdir.call_args_list, expected)
+        self.assertEqual(service.call_args_list, [mock.call('enable', 'jenkins-slave')])
+        self.assertEqual(apt_purge.call_args_list, [mock.call(['jenkins-slave'])])
+        expected = [mock.call('files/download-slave.sh', '/usr/local/sbin/download-slave.sh'),
+                    mock.call('files/jenkins-slave-logrotate-config', '/etc/logrotate.d/jenkins-slave'),
+                    mock.call('files/jenkins-slave-systemd-config', '/lib/systemd/system/jenkins-slave.service')]
+        self.assertEqual(file_to_units.call_args_list, expected)
+        self.assertEqual(write_default_conf.call_args_list, [mock.call()])
+        expected = [mock.call.queue_install(['wget', 'default-jre-headless']),
+                    mock.call.install_queued()]
+        self.assertEqual(apt.method_calls, expected)
+
+    @mock.patch('charms.reactive.clear_flag')
+    @mock.patch('charms.reactive.set_flag')
+    @mock.patch('charmhelpers.core.hookenv.config')
+    @mock.patch('charmhelpers.core.unitdata.kv')
+    @mock.patch('reactive.jenkins_slave.write_default_conf')
+    @mock.patch('reactive.jenkins_slave.file_to_units')
+    def test_configure_jenkins_slave_no_url(self, file_to_units, write_default_conf, unitdata_kv, config,
+                                            set_flag, clear_flag):
+        config.return_value = {}
+        unitdata_kv.return_value = {}
+        configure_jenkins_slave()
+        self.assertEqual(write_default_conf.call_args_list, [])
+        self.assertEqual(set_flag.call_args_list, [mock.call('jenkins-slave.blocked')])
+        self.assertEqual(clear_flag.call_args_list, [mock.call('jenkins-slave.active')])
+
+    @mock.patch('charms.reactive.clear_flag')
+    @mock.patch('charms.reactive.set_flag')
+    @mock.patch('charmhelpers.core.hookenv.config')
+    @mock.patch('charmhelpers.core.unitdata.kv')
+    @mock.patch('reactive.jenkins_slave.write_default_conf')
+    @mock.patch('reactive.jenkins_slave.file_to_units')
+    def test_configure_jenkins_slave_master_url(self, file_to_units, write_default_conf, unitdata_kv, config,
+                                                set_flag, clear_flag):
+        config.return_value = {'master_url': 'http://10.1.1.1:8080'}
+        unitdata_kv.return_value = {}
+        configure_jenkins_slave()
+        self.assertEqual(write_default_conf.call_args_list, [mock.call('http://10.1.1.1:8080')])
+        self.assertEqual(set_flag.call_args_list, [mock.call('jenkins-slave.configured')])
+        expected = [mock.call('jenkins-slave.active'), mock.call('nagios-nrpe.configured')]
+        self.assertEqual(clear_flag.call_args_list, expected)
+
+    @mock.patch('charms.reactive.clear_flag')
+    @mock.patch('charms.reactive.set_flag')
+    @mock.patch('charmhelpers.core.hookenv.config')
+    @mock.patch('charmhelpers.core.unitdata.kv')
+    @mock.patch('reactive.jenkins_slave.write_default_conf')
+    @mock.patch('reactive.jenkins_slave.file_to_units')
+    def test_configure_jenkins_slave_relation_url(self, file_to_units, write_default_conf, unitdata_kv, config,
+                                                  set_flag, clear_flag):
+        config.return_value = {}
+        unitdata_kv.return_value = {'url': 'http://10.22.22.22:8080'}
+        configure_jenkins_slave()
+        print(write_default_conf.call_args_list)
+        self.assertEqual(write_default_conf.call_args_list, [mock.call('http://10.22.22.22:8080')])
+        self.assertEqual(set_flag.call_args_list, [mock.call('jenkins-slave.configured')])
+        expected = [mock.call('jenkins-slave.active'), mock.call('nagios-nrpe.configured')]
+        self.assertEqual(clear_flag.call_args_list, expected)
+
+    def test_write_default_conf_update(self):
+        write_default_conf('http://10.1.1.1:8080', self.user, self.group, self.conf_file)
+        self.assertTrue(conf_match(self.conf_file, 'JENKINS_URL', 'http://10.1.1.1:8080'))
+
+    def test_write_default_conf_reset(self):
+        write_default_conf(None, self.user, self.group, self.conf_file)
+        self.assertTrue(conf_match(self.conf_file, '#JENKINS_URL', ''))
+
+    def test_file_to_units_executable_sh(self):
+        source = os.path.join(self.charm_dir, 'files/download-slave.sh')
+        dest = os.path.join(self.tmpdir, os.path.basename(source))
+        file_to_units(source, dest, owner=self.user, group=self.group)
+        with open(dest, 'rb') as fh:
+            want = fh.read().decode('utf-8')
+        self.assertTrue(conf_equals(source, want))
+        self.assertEqual(pwd.getpwuid(os.stat(dest).st_uid).pw_name, self.user)
+        self.assertEqual(grp.getgrgid(os.stat(dest).st_gid).gr_name, self.group)
+        self.assertTrue(os.access(dest, os.X_OK))
+
+    def test_file_to_units_executable_py(self):
+        source = os.path.join(self.charm_dir, 'tests/unit/files/somefile.py')
+        dest = os.path.join(self.tmpdir, os.path.basename(source))
+        file_to_units(source, dest, owner=self.user, group=self.group)
+        with open(dest, 'rb') as fh:
+            want = fh.read().decode('utf-8')
+        self.assertTrue(conf_equals(source, want))
+        self.assertEqual(pwd.getpwuid(os.stat(dest).st_uid).pw_name, self.user)
+        self.assertEqual(grp.getgrgid(os.stat(dest).st_gid).gr_name, self.group)
+        self.assertTrue(os.access(dest, os.X_OK))
+
+    def test_file_to_units_non_executable(self):
+        source = os.path.join(self.charm_dir, 'files/jenkins-slave-logrotate-config')
+        dest = os.path.join(self.tmpdir, os.path.basename(source))
+        file_to_units(source, dest, owner=self.user, group=self.group)
+        with open(dest, 'rb') as fh:
+            want = fh.read().decode('utf-8')
+        self.assertTrue(conf_equals(dest, want))
+        self.assertEqual(pwd.getpwuid(os.stat(dest).st_uid).pw_name, self.user)
+        self.assertEqual(grp.getgrgid(os.stat(dest).st_gid).gr_name, self.group)
+        self.assertFalse(os.access(dest, os.X_OK))
+
+    def test_file_to_units_non_executable_x_on_disk(self):
+        source = os.path.join(self.charm_dir, 'tests/unit/files/somefile')
+        dest = os.path.join(self.tmpdir, os.path.basename(source))
+        file_to_units(source, dest, owner=self.user, group=self.group)
+        with open(dest, 'rb') as fh:
+            want = fh.read().decode('utf-8')
+        self.assertTrue(conf_equals(source, want))
+        self.assertEqual(pwd.getpwuid(os.stat(dest).st_uid).pw_name, self.user)
+        self.assertEqual(grp.getgrgid(os.stat(dest).st_gid).gr_name, self.group)
+        self.assertFalse(os.access(dest, os.X_OK))
+
+
+def conf_equals(conf_file, want):
+    with open(conf_file, 'rb') as conf:
+        got = conf.read().decode('utf-8')
+        if got == want:
+            return True
+        print('{}\n != \n{}'.format(got, want))
+    return False
+
+
+def conf_match(conf_file, key, value):
+    with open(conf_file, 'rb') as conf:
+        for line in conf.readlines():
+            line = line.decode('utf-8').rstrip('\n')
+            if line == '{}="{}"'.format(key, value):
+                return True
+    return False
+
+
+if __name__ == '__main__':
+    unittest.main()
 
=== added file 'tox.ini'
--- tox.ini	1970-01-01 00:00:00 +0000
+++ tox.ini	2019-03-01 05:39:53 +0000
@@ -0,0 +1,37 @@
+[tox]
+skipsdist=True
+envlist = unit, functional
+skip_missing_interpreters = True
+
+[testenv]
+basepython = python3
+setenv =
+  PYTHONPATH = .
+
+[testenv:unit]
+commands = pytest -v --ignore {toxinidir}/tests/functional --cov=lib --cov=reactive --cov=actions --cov-report=term
+deps = -r{toxinidir}/tests/unit/requirements.txt
+       -r{toxinidir}/requirements.txt
+setenv = PYTHONPATH={toxinidir}/lib
+
+[testenv:functional]
+passenv =
+  HOME
+  JUJU_REPOSITORY
+  PATH
+commands = pytest -v --ignore {toxinidir}/tests/unit
+deps = -r{toxinidir}/tests/functional/requirements.txt
+       -r{toxinidir}/requirements.txt
+
+[testenv:lint]
+commands = flake8
+deps = flake8
+
+[flake8]
+exclude =
+    .git,
+    __pycache__,
+    .tox,
+    hooks/install.d/,
+max-line-length = 120
+max-complexity = 10