Simplify curator extension

extensions/curator/Dockerfile

@@ -1,13 +1,17 @@
-FROM alpine:3.8
+FROM bitnami/elasticsearch-curator:5.8.1
 
-ENV CURATOR_VERSION=5.8.1
+USER root
 
-RUN apk --update add --no-cache tini python py-pip \
-  && pip install elasticsearch-curator==${CURATOR_VERSION}
+RUN install_packages cron && \
+    echo \
+        '* * * * *' \
+        root \
+        LC_ALL=C.UTF-8 LANG=C.UTF-8 \
+        /opt/bitnami/python/bin/curator \
+        --config=/usr/share/curator/config/curator.yml \
+        /usr/share/curator/config/delete_log_files_curator.yml \
+        '>/proc/1/fd/1' '2>/proc/1/fd/2' \
+        >>/etc/crontab
 
-COPY entrypoint.sh /
-
-WORKDIR /usr/share/curator
-COPY config ./config
-
-ENTRYPOINT ["/entrypoint.sh"]
+ENTRYPOINT ["cron"]
+CMD ["-f", "-L8"]

extensions/curator/README.md

@@ -11,8 +11,10 @@ command line argument referencing the `curator-compose.yml` file:
 $ docker-compose -f docker-compose.yml -f extensions/curator/curator-compose.yml up
 ```
 
+This sample setup demonstrates how to run `curator` every minute using `cron`.
+
 All configuration files are available in the `config/` directory.
 
 ## Documentation
 
-https://github.com/elastic/curator
+https://www.elastic.co/guide/en/elasticsearch/client/curator/current/index.html

extensions/curator/config/curator.yml

@@ -1,24 +1,12 @@
----
-# Remember, leave a key empty if there is no value. None will be a string,
-# not a Python "NoneType"
+# Curator configuration
+# https://www.elastic.co/guide/en/elasticsearch/client/curator/current/configfile.html
+
 client:
   hosts:
-    - ${ELASTICSEARCH_HOST}
+    - elasticsearch
   port: 9200
-  url_prefix:
-  use_ssl: False
-  certificate:
-  client_cert:
-  client_key:
-  aws_key:
-  aws_secret_key:
-  aws_region:
-  ssl_no_validate: False
-  http_auth:
-  timeout: 30
-  master_only: False
+  http_auth: elastic:changeme
 
 logging:
-  loglevel: DEBUG
-  logfile:
+  loglevel: INFO
   logformat: default

extensions/curator/config/delete_log_files_curator.yml

@@ -2,10 +2,11 @@ actions:
   1:
     action: delete_indices
     description: >-
-      Delete indices. Find which to delete by first limiting the list to logstash-
-      prefixed indices. Then further filter those to prevent deletion of anything
-      less than ${UNIT_COUNT} days old. Ignore the error if the filter does not result in an
-      actionable list of indices (ignore_empty_list) and exit cleanly.
+      Delete indices. Find which to delete by first limiting the list to
+      logstash- prefixed indices. Then further filter those to prevent deletion
+      of anything less than the number of days specified by unit_count.
+      Ignore the error if the filter does not result in an actionable list of
+      indices (ignore_empty_list) and exit cleanly.
     options:
       ignore_empty_list: True
       disable_action: False
@@ -17,4 +18,4 @@ actions:
       source: creation_date
       direction: older
       unit: days
-      unit_count: ${UNIT_COUNT}
+      unit_count: 2

extensions/curator/curator-compose.yml

@@ -4,12 +4,16 @@ services:
   curator:
     build:
       context: extensions/curator/
-    environment:
-      ELASTICSEARCH_HOST: elasticsearch
-      CRON: 0 0 * * *
-      CONFIG_FILE: /usr/share/curator/config/curator.yml
-      COMMAND: /usr/share/curator/config/delete_log_files_curator.yml
-      UNIT_COUNT: 2
+    init: true
+    volumes:
+      - type: bind
+        source: ./extensions/curator/config/curator.yml
+        target: /usr/share/curator/config/curator.yml
+        read_only: true
+      - type: bind
+        source: ./extensions/curator/config/delete_log_files_curator.yml
+        target: /usr/share/curator/config/delete_log_files_curator.yml
+        read_only: true
     networks:
       - elk
     depends_on:

extensions/curator/entrypoint.sh

@@ -1,6 +0,0 @@
-#!/bin/sh
-
-echo "$CRON /usr/bin/curator  --config ${CONFIG_FILE} ${COMMAND}" >>/etc/crontabs/root
-
-# https://github.com/krallin/tini/blob/master/README.md#subreaping
-tini -s -- crond -f -d 8 -l 8