Add Journalbeat docker image (#58)

This PR adds Journalbeat to the available Beats.

README.md

@@ -8,6 +8,7 @@ Documentation can be found on the [Elastic website][elastic]:
 * [auditbeat][auditbeat]
 * [filebeat][filebeat]
 * [heartbeat][heartbeat]
+* [journalbeat][journalbeat]
 * [metricbeat][metricbeat]
 * [packetbeat][packetbeat]
 
@@ -16,6 +17,7 @@ Documentation can be found on the [Elastic website][elastic]:
 [auditbeat]: https://www.elastic.co/guide/en/beats/auditbeat/current/running-on-docker.html
 [filebeat]: https://www.elastic.co/guide/en/beats/filebeat/current/running-on-docker.html
 [heartbeat]: https://www.elastic.co/guide/en/beats/heartbeat/current/running-on-docker.html
+[journalbeat]: https://www.elastic.co/guide/en/beats/journalbeat/current/running-on-docker.html
 [metricbeat]: https://www.elastic.co/guide/en/beats/metricbeat/current/running-on-docker.html
 [packetbeat]: https://www.elastic.co/guide/en/beats/packetbeat/current/running-on-docker.html
 

beats.txt

@@ -1,5 +1,6 @@
 auditbeat
 filebeat
 heartbeat
+journalbeat
 metricbeat
 packetbeat

build/journalbeat/config/journalbeat.yml

@@ -0,0 +1,11 @@
+journalbeat.inputs:
+- paths: []
+
+processors:
+- add_host_metadata:
+- add_cloud_metadata:
+
+output.elasticsearch:
+  hosts: ['elasticsearch:9200']
+  username: elastic
+  password: changeme

templates/docker-compose.yml.j2

@@ -24,4 +24,10 @@ services:
       - NET_RAW
       - NET_ADMIN
     {%- endif %}
+
+    {% if beat == 'journalbeat' %}
+    volumes:
+      - /etc/machine-id:/etc/machine-id
+      - /etc/hostname:/etc/hostname:ro
+    {%- endif %}
 {% endfor %}