Improve Redis support by mounting read-write redis-session.ini into the container

Related to https://github.com/nextcloud/docker/issues/763

Fixes https://github.com/mother-of-all-self-hosting/ansible-role-nextcloud/issues/4

defaults/main.yml

@@ -24,6 +24,7 @@ nextcloud_systemd_required_services_list_custom: []
 nextcloud_base_path: "{{ nextcloud_base_path }}/nextcloud"
 nextcloud_config_path: "{{ nextcloud_base_path }}/config"
 nextcloud_data_path: "{{ nextcloud_base_path }}/data"
+nextcloud_redis_session_ini_path: "{{ nextcloud_base_path }}/redis-session.ini"
 nextcloud_customized_container_src_path: "{{ nextcloud_base_path }}/customized-container-src"
 
 # SVG support for imagick can be setup like this:

tasks/install.yml

@@ -1,17 +1,28 @@
 ---
 
-- name: Ensure Nextcloud path exists
+- name: Ensure Nextcloud paths exists
   ansible.builtin.file:
     path: "{{ item.path }}"
-    state: directory
+    state: "{{ item.state }}"
     mode: 0700
     owner: "{{ nextcloud_uid }}"
     group: "{{ nextcloud_gid }}"
   with_items:
-    - {path: "{{ nextcloud_base_path }}", when: true}
-    - {path: "{{ nextcloud_config_path }}", when: true}
-    - {path: "{{ nextcloud_data_path }}", when: true}
-    - {path: "{{ nextcloud_customized_container_src_path }}", when: "{{ nextcloud_container_image_customizations_enabled }}"}
+    - path: "{{ nextcloud_base_path }}"
+      state: directory
+      when: true
+    - path: "{{ nextcloud_config_path }}"
+      state: directory
+      when: true
+    - path: "{{ nextcloud_data_path }}"
+      state: directory
+      when: true
+    - path: "{{ nextcloud_customized_container_src_path }}"
+      state: directory
+      when: "{{ nextcloud_container_image_customizations_enabled }}"
+    - path: "{{ nextcloud_redis_session_ini_path }}"
+      state: "{{ 'touch' if nextcloud_redis_is_configured else 'absent' }}"
+      when: true
   when: item.when | bool
 
 - name: Ensure Nextcloud support files installed

templates/systemd/server.service.j2

@@ -12,6 +12,13 @@ Environment="HOME={{ devture_systemd_docker_base_systemd_unit_home_path }}"
 ExecStartPre=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} kill {{ nextcloud_identifier }}-server 2>/dev/null || true'
 ExecStartPre=-{{ devture_systemd_docker_base_host_command_sh }} -c '{{ devture_systemd_docker_base_host_command_docker }} rm {{ nextcloud_identifier }}-server 2>/dev/null || true'
 
+{#
+	`redis-session.ini` is mounted from the host, because the container's entrypoint tries to modify `/usr/local/etc/php/conf.d/redis-session.ini`
+	during startup when Redis is enabled and it can't do it on a `--read-only` filesystem.
+	See:
+	- https://github.com/nextcloud/docker/issues/763
+	- https://github.com/nextcloud/docker/blob/289f0bb8a3f1bd24d1633bbd01798c5476368827/26/apache/entrypoint.sh#L75-L100
+#}
 ExecStartPre={{ devture_systemd_docker_base_host_command_docker }} create \
 			--rm \
 			--name={{ nextcloud_identifier }}-server \
@@ -21,6 +28,9 @@ ExecStartPre={{ devture_systemd_docker_base_host_command_docker }} create \
 			--cap-drop=ALL \
 			--read-only \
 			--mount type=bind,src={{ nextcloud_data_path }},dst=/var/www/html \
+			{% if nextcloud_redis_is_configured %}
+			--mount type=bind,src={{ nextcloud_redis_session_ini_path }},dst=/usr/local/etc/php/conf.d/redis-session.ini \
+			{% endif %}
 			{% for mount in nextcloud_container_additional_mounts %}
 			--mount {{ mount }} \
 			{% endfor %}

vars/main.yml

@@ -1 +1,3 @@
 nextcloud_url: "{{ nextcloud_scheme }}://{{ nextcloud_hostname }}{{ nextcloud_path_prefix }}"
+
+nextcloud_redis_is_configured: "{{ nextcloud_redis_hostname != '' }}"