databases: use initdb folder to create DBs and users

This way when the database is cleared the user is automatically created
without the need to run Ansible.

Signed-off-by: Jakub Sokołowski <jakub@status.im>

README.md

@@ -31,6 +31,8 @@ postgres_ha_databases:
 ```
 The `user` field is optional. DB name is used by default.
 
+:warning: __WARNING:__ This only takes effect at database creation.
+
 Backup settings can be adjusted using:
 ```yaml
 postgres_ha_backup: false

defaults/main.yml

@@ -5,6 +5,7 @@ postgres_ha_compose_file: '{{ postgres_ha_service_path }}/docker-compose.yml'
 
 postgres_ha_cont_name: '{{ postgres_ha_service_name }}'
 postgres_ha_cont_data_vol: '{{ postgres_ha_service_path }}/data'
+postgres_ha_cont_init_vol: '{{ postgres_ha_service_path }}/init'
 postgres_ha_cont_backup_vol: '{{ postgres_ha_service_path }}/backup'
 postgres_ha_cont_image: 'postgres:15.1-alpine'
 postgres_ha_cont_port: 5432

tasks/config.yml

@@ -9,8 +9,20 @@
   with_items:
     - '{{ postgres_ha_service_path }}'
     - '{{ postgres_ha_cont_data_vol }}'
+    - '{{ postgres_ha_cont_init_vol }}'
     - '{{ postgres_ha_cont_backup_vol }}'
 
+- name: Create dbinit SQL files
+  when: postgres_ha_is_master
+  template:
+    src:   '{{ item }}'
+    dest:  '{{ postgres_ha_cont_init_vol }}/{{ item | basename }}'
+    owner: '{{ postgres_ha_host_uid }}'
+    group: 'dockremap'
+    mode:  0640
+  with_fileglob:
+    - 'templates/init/*.sql'
+
 - name: 'Create compose file'
   template:
     src:   'docker-compose.yml.j2'

tasks/databases.yml

@@ -1,25 +0,0 @@
----
-- name: 'Create user: {{ db.get("user", db.name) }}'
-  command: >
-    docker exec {{ postgres_ha_cont_name }}
-      psql
-        --username={{ postgres_ha_admin_user }}
-        --port={{ postgres_ha_cont_port }}
-        --command
-      "DO $$
-      BEGIN
-        CREATE USER \"{{ db.get("user", db.name) }}\" PASSWORD '{{ db.pass | mandatory }}';
-        EXCEPTION WHEN DUPLICATE_OBJECT THEN
-        RAISE NOTICE 'not creating role {{ db.get("user", db.name) }} -- it already exists';
-      END
-      $$;"
-
-- name: 'Create database: {{ db.name | mandatory }}'
-  shell: >
-    echo "SELECT
-        'CREATE DATABASE \"{{ db.name }}\" WITH OWNER \"{{ db.get("user", db.name) }}\";'
-        WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = '{{ db.name }}')\\\gexec" |
-    docker exec -i {{ postgres_ha_cont_name }} \
-      psql \
-        --username={{ postgres_ha_admin_user }} \
-        --port={{ postgres_ha_cont_port }}

tasks/main.yml

@@ -16,12 +16,6 @@
 - import_tasks: start.yml
   when: not postgres_ha_is_master
 
-- include_tasks: databases.yml
-  when: postgres_ha_is_master
-  with_items: '{{ postgres_ha_databases }}'
-  loop_control:
-    loop_var: db
-
 - import_tasks: consul.yml
 
 - import_tasks: backup.yml

templates/docker-compose.yml.j2

@@ -21,6 +21,7 @@ services:
       - '/tmp:size={{ postgres_ha_cont_tmp_size }}'
     volumes:
       - '{{ postgres_ha_cont_data_vol }}:/var/lib/postgresql/data'
+      - '{{ postgres_ha_cont_init_vol }}:/docker-entrypoint-initdb.d'
       - '{{ postgres_ha_cont_backup_vol }}:/backup'
     command: |
       -p {{ postgres_ha_cont_port }}

templates/init/databases.sql

@@ -0,0 +1,7 @@
+-- File managed by Ansible.
+{% for db in postgres_ha_databases %}
+
+-- Create {{ db.name }} database.
+CREATE USER "{{ db.get("user", db.name) }}" PASSWORD '{{ db.pass | mandatory }}';
+CREATE DATABASE "{{ db.name }}" WITH OWNER "{{ db.get("user", db.name) }}";
+{% endfor %}