feat(elasticsearch): add role for single-node deployment using docker containers

README.md

@@ -11,6 +11,10 @@ concise area of concern.
 - [`roles/authelia`](roles/authelia/README.md): Deploys an [authelia.com](https://www.authelia.com)
   instance, an authentication provider with beta OIDC provider support.
 
+- [`roles/elasticsearch`](roles/elasticsearch/README.md): Deploy [elasticsearch](https://www.docker.elastic.co/r/elasticsearch/elasticsearch-oss),
+  a popular (distributed) search and analytics engine, mostly known by it's
+  letter "E" in the ELK-stack.
+
 - [`roles/gitea`](roles/gitea/README.md): Deploy [gitea.io](https://gitea.io), a
   lightweight, self-hosted git service.
 

roles/elasticsearch/README.md

@@ -0,0 +1,22 @@
+# `finallycoffee.services.elastiscsearch`
+
+A simple ansible role which deploys a single-node elastic container to provide
+an easy way to do some indexing.
+
+## Usage
+
+Per default, `/opt/elasticsearch/data` is used to persist data, it is
+customizable by using either `elasticsearch_base_path` or `elasticsearch_data_path`.
+
+As elasticsearch be can be quite memory heavy, the maximum amount of allowed RAM
+can be configured using `elasticsearch_allocated_ram_mb`, defaulting to 512 (mb).
+
+The cluster name and discovery type can be overridden using
+`elasticsearch_config_cluster_name` (default: elastic) and
+`elasticsearch_config_discovery_type` (default: single-node), should one
+need a multi-node elasticsearch deployment.
+
+Per default, no ports or networks are mapped, and explizit mapping using
+either ports (`elasticsearch_container_ports`) or networks
+(`elasticsearch_container_networks`) is required in order for other services
+to use elastic.

roles/elasticsearch/defaults/main.yml

@@ -0,0 +1,35 @@
+---
+
+elasticsearch_version: 7.10.2
+
+elasticsearch_base_path: /opt/elasticsearch
+elasticsearch_data_path: "{{ elasticsearch_base_path }}/data"
+
+elasticsearch_config_cluster_name: elastic
+elasticsearch_config_discovery_type: single-node
+elasticsearch_config_boostrap_memory_lock: true
+elasticsearch_allocated_ram_mb: 512
+
+elasticsearch_container_image_name: docker.elastic.co/elasticsearch/elasticsearch-oss
+elasticsearch_container_image_tag: ~
+elasticsearch_container_image: >-
+  {{ elasticsearch_container_image_name }}:{{ elasticsearch_container_image_tag | default(elasticsearch_version, true) }}
+
+elasticsearch_container_name: elasticsearch
+elasticsearch_container_env:
+  "ES_JAVA_OPTS": "-Xms{{ elasticsearch_allocated_ram_mb }}m -Xmx{{ elasticsearch_allocated_ram_mb }}m"
+  "cluster.name": "{{ elasticsearch_config_cluster_name }}"
+  "discovery.type": "{{ elasticsearch_config_discovery_type }}"
+  "bootstrap.memory_lock": "{{ 'true' if elasticsearch_config_boostrap_memory_lock else 'false' }}"
+elasticsearch_container_user: ~
+elasticsearch_container_ports: ~
+elasticsearch_container_labels:
+  version: "{{ elasticsearch_version }}"
+elasticsearch_container_ulimits:
+#  - "memlock:{{ (1.5 * 1024 * elasticsearch_allocated_ram_mb) | int }}:{{ (1.5 * 1024 * elasticsearch_allocated_ram_mb) | int }}"
+  - "memlock:-1:-1"
+elasticsearch_container_volumes:
+  - "{{ elasticsearch_data_path }}:/usr/share/elasticsearch/data:z"
+elasticsearch_container_networks: ~
+elasticsearch_container_purge_networks: ~
+elasticsearch_container_restart_policy: unless-stopped

roles/elasticsearch/tasks/main.yml

@@ -0,0 +1,32 @@
+---
+
+- name: Ensure host directories are present
+  file:
+    path: "{{ item }}"
+    state: directory
+    mode: "0777"
+  loop:
+    - "{{ elasticsearch_base_path }}"
+    - "{{ elasticsearch_data_path }}"
+
+- name: Ensure elastic container image is present
+  docker_image:
+    name: "{{ elasticsearch_container_image }}"
+    state: present
+    source: pull
+    force_source: "{{ elasticsearch_container_image_tag|default(false, true)|bool }}"
+
+- name: Ensure elastic container is running
+  docker_container:
+    name: "{{ elasticsearch_container_name }}"
+    image: "{{ elasticsearch_container_image }}"
+    env: "{{ elasticsearch_container_env | default(omit, True) }}"
+    user: "{{ elasticsearch_container_user | default(omit, True) }}"
+    ports: "{{ elasticsearch_container_ports | default(omit, True) }}"
+    labels: "{{ elasticsearch_container_labels | default(omit, True) }}"
+    volumes: "{{ elasticsearch_container_volumes }}"
+    ulimits: "{{ elasticsearch_container_ulimits }}"
+    networks: "{{ elasticsearch_container_networks | default(omit, True) }}"
+    purge_networks: "{{ elasticsearch_container_purge_networks | default(omit, True) }}"
+    restart_policy: "{{ elasticsearch_container_restart_policy }}"
+    state: started