Add Logstash 6 for Monasca on Centos 8

On Centos 8 we have Elasticsearch and Kibana 6, but Logstash (used by
Monasca) is stuck on 2 which is not compatible. See the product
compatibility matrix [1]. This adds Logstash 6, so that Monasca
can use the full ELK 6 stack on Centos 8.

Note that Monasca doesn't officially support ELK 6, but it does work.

[1] https://www.elastic.co/support/matrix#matrix_compatibility

Partial-Bug: #1884090
Change-Id: Id6f79e301cc109a029913f5628bab1848c138e7f

3 files changed, 43 insertions, 0 deletions

diff --git a/docker/logstash6/Dockerfile.j2 b/docker/logstash6/Dockerfile.j2
new file mode 100644
index 000000000..7368f58b2
--- /dev/null
+++ b/docker/logstash6/Dockerfile.j2
@@ -0,0 +1,29 @@
+FROM {{ namespace }}/{{ image_prefix }}base:{{ tag }}
+{% block labels %}
+LABEL maintainer="{{ maintainer }}" name="{{ image_name }}" build-date="{{ build_date }}"
+{% endblock %}
+
+{% block logstash_header %}{% endblock %}
+
+{% import "macros.j2" as macros with context %}
+
+{{ macros.configure_user(name='logstash', shell='/bin/bash', homedir='/usr/share/logstash') }}
+
+ENV JAVA_HOME /usr/lib/jvm/jre-11-openjdk/
+
+{% set logstash_packages = [
+    'java-11-openjdk-headless',
+    'logstash-oss',
+] %}
+
+COPY elasticsearch.repo /etc/yum.repos.d/
+
+{{ macros.install_packages(logstash_packages | customizable("packages")) }}
+COPY extend_start.sh /usr/local/bin/kolla_extend_start
+
+RUN chmod 755 /usr/local/bin/kolla_extend_start
+
+{% block logstash_footer %}{% endblock %}
+{% block footer %}{% endblock %}
+
+USER logstash
diff --git a/docker/logstash6/elasticsearch.repo b/docker/logstash6/elasticsearch.repo
new file mode 100644
index 000000000..7172d13a8
--- /dev/null
+++ b/docker/logstash6/elasticsearch.repo
@@ -0,0 +1,6 @@
+[elasticsearch-kibana-logstash-6.x]
+name=ELK repository for 6.x packages
+baseurl=https://artifacts.elastic.co/packages/oss-6.x/yum
+gpgcheck=1
+gpgkey=https://artifacts.elastic.co/GPG-KEY-elasticsearch
+enabled=1
diff --git a/docker/logstash6/extend_start.sh b/docker/logstash6/extend_start.sh
new file mode 100644
index 000000000..99152b1b5
--- /dev/null
+++ b/docker/logstash6/extend_start.sh
@@ -0,0 +1,8 @@
+#!/bin/bash
+
+if [[ ! -d "/var/log/kolla/logstash" ]]; then
+    mkdir -p /var/log/kolla/logstash
+fi
+if [[ $(stat -c %a /var/log/kolla/logstash) != "755" ]]; then
+    chmod 755 /var/log/kolla/logstash
+fi