Some improvements, including elasticsearch.yml configuration

defaults/main.yml

@@ -1,2 +1,5 @@
 ---
 elasticsearch_nextcloud_os_supported: False
+
+elasticsearch_nextcloud_host: "127.0.0.1"
+elasticsearch_nextcloud_port: "9200"

tasks/main.yml

@@ -41,3 +41,14 @@
       - elasticsearch=6.1.0
     state: latest
     update_cache: yes
+
+- name: Set config file
+  template:
+    src: elasticsearch.yml.j2
+    dest: /etc/elasticsearch/elasticsearch.yml
+    owner: root
+    group: elasticsearch
+
+- name: Enable ingest-attachment plugin
+  shell:
+    cmd: "{{ nextcloud_elasticsearch_bin_dir }}/elasticsearch-plugin install ingest-attachment"

templates/elasticsearch.yml.j2

@@ -0,0 +1,88 @@
+# ======================== Elasticsearch Configuration =========================
+#
+# NOTE: Elasticsearch comes with reasonable defaults for most settings.
+#       Before you set out to tweak and tune the configuration, make sure you
+#       understand what are you trying to accomplish and the consequences.
+#
+# The primary way of configuring a node is via this file. This template lists
+# the most important settings you may want to configure for a production cluster.
+#
+# Please consult the documentation for further information on configuration options:
+# https://www.elastic.co/guide/en/elasticsearch/reference/index.html
+#
+# ---------------------------------- Cluster -----------------------------------
+#
+# Use a descriptive name for your cluster:
+#
+#cluster.name: my-application
+#
+# ------------------------------------ Node ------------------------------------
+#
+# Use a descriptive name for the node:
+#
+#node.name: node-1
+#
+# Add custom attributes to the node:
+#
+#node.attr.rack: r1
+#
+# ----------------------------------- Paths ------------------------------------
+#
+# Path to directory where to store the data (separate multiple locations by comma):
+#
+path.data: {{ elasticsearch_nextcloud_data_path }}
+#
+# Path to log files:
+#
+path.logs: /var/log/elasticsearch
+#
+# ----------------------------------- Memory -----------------------------------
+#
+# Lock the memory on startup:
+#
+#bootstrap.memory_lock: true
+#
+# Make sure that the heap size is set to about half the memory available
+# on the system and that the owner of the process is allowed to use this
+# limit.
+#
+# Elasticsearch performs poorly when the system is swapping the memory.
+#
+# ---------------------------------- Network -----------------------------------
+#
+# Set the bind address to a specific IP (IPv4 or IPv6):
+#
+network.host: {{ elasticsearch_nextcloud_host }}
+#
+# Set a custom port for HTTP:
+#
+http.port: {{ elasticsearch_nextcloud_port }}
+#
+# For more information, consult the network module documentation.
+#
+# --------------------------------- Discovery ----------------------------------
+#
+# Pass an initial list of hosts to perform discovery when new node is started:
+# The default list of hosts is ["127.0.0.1", "[::1]"]
+#
+#discovery.zen.ping.unicast.hosts: ["host1", "host2"]
+#
+# Prevent the "split brain" by configuring the majority of nodes (total number of master-eligible nodes / 2 + 1):
+#
+#discovery.zen.minimum_master_nodes: 
+#
+# For more information, consult the zen discovery module documentation.
+#
+# ---------------------------------- Gateway -----------------------------------
+#
+# Block initial recovery after a full cluster restart until N nodes are started:
+#
+#gateway.recover_after_nodes: 3
+#
+# For more information, consult the gateway module documentation.
+#
+# ---------------------------------- Various -----------------------------------
+#
+# Require explicit names when deleting indices:
+#
+#action.destructive_requires_name: true

vars/debian.yml

@@ -1,2 +1,5 @@
 ---
 elasticsearch_nextcloud_os_supported: True
+
+elasticsearch_nextcloud_data_path: "/var/lib/elasticsearch"
+nextcloud_elasticsearch_bin_dir: "/usr/share/elasticsearch/bin"