Environment vars (sleighzy#2)

* Added support for Env Vars

* Added default value for zookeeper_environment

* Updated README to show EnvVars example

* Update README with file info for defaults.

* Change default template to support Python3

README.md

@@ -34,6 +34,8 @@ The Oracle Java 8 JDK role from Ansible Galaxy can be used if one is needed.
     zookeeper_election_port: 3888
     zookeeper_mirror: "http://www-eu.apache.org/dist/zookeeper"
     zookeeper_servers: "{{groups['zookeeper-nodes']}}"
+    zookeeper_environment:
+        "JVMFLAGS": "-javaagent:/opt/jolokia/jolokia-jvm-1.6.0-agent.jar"
 
 
 ### Default Ports
@@ -47,15 +49,16 @@ The Oracle Java 8 JDK role from Ansible Galaxy can be used if one is needed.
 
 ### Default Directories and Files
 
-| Directory / File | |
-|-----|----|
-| Installation directory | `/usr/share/zookeeper-<version>`
-| Symlink to install directory | `/usr/share/zookeeper` |
-| Symlink to configuration | `/etc/zookeeper/zoo.cfg` |
-| Log files | `/var/log/zookeeper` |
-| Data directory for snapshots and myid file | `/var/lib/zookeeper` |
-| Data directory for transaction log files | `/var/lib/zookeeper` |
-| Systemd service | `/usr/lib/systemd/system/zookeeper.service` |
+ Description                               | Directory / File 
+-------------------------------------------|------------------
+Installation directory                     | `/usr/share/zookeeper-<version>`
+Symlink to install directory               | `/usr/share/zookeeper` 
+Symlink to configuration                   | `/etc/zookeeper/zoo.cfg` 
+Log files                                  | `/var/log/zookeeper` 
+Data directory for snapshots and myid file | `/var/lib/zookeeper` 
+Data directory for transaction log files   | `/var/lib/zookeeper` 
+Systemd service                            | `/usr/lib/systemd/system/zookeeper.service` 
+System Defaults                            | `/etc/default/zookeeper` 
 
 ## Starting and Stopping ZooKeeper services
 * The ZooKeeper service can be started via: `systemctl start zookeeper`

defaults/main.yaml

@@ -24,4 +24,5 @@ zookeeper_id: 1
 zookeeper_leader_port: 2888
 zookeeper_election_port: 3888
 
-zookeeper_servers: "{{groups['zookeeper-nodes']}}"
+zookeeper_servers: "{{groups['zookeeper-nodes']}}"
+zookeeper_environment: {}

tasks/main.yaml

@@ -114,6 +114,15 @@
   tags:
     - zookeeper_config
 
+- name: Template /etc/default
+  template:
+    src: default.j2
+    dest: '/etc/default/zookeeper'
+  notify:
+    - Restart ZooKeeper service
+  tags:
+    - zookeeper_config
+
 # Uncomment the log4j.properties line for setting the maximum number of logs to rollover and keep
 - name: Set maximum log rollover history
   replace:

templates/default.j2

@@ -0,0 +1,6 @@
+ZOO_LOG_DIR={{ zookeeper_log_dir }}
+ZOO_LOG4J_PROP=INFO,ROLLINGFILE
+
+{% for key, value in zookeeper_environment.items() %}
+{{key}}={{value}}
+{% endfor %}

templates/zookeeper.service.j2

@@ -6,8 +6,7 @@ After=network.target
 
 [Service]
 Type=forking
-Environment='ZOO_LOG_DIR={{ zookeeper_log_dir }}'
-Environment='ZOO_LOG4J_PROP=INFO,ROLLINGFILE'
+EnvironmentFile=/etc/default/zookeeper
 ExecStart={{ zookeeper_dir }}/bin/zkServer.sh start
 ExecStop={{ zookeeper_dir }}/bin/zkServer.sh stop
 Restart=on-failure