Make Riot-web configuration extensible

Fixes #71 (Github Issue).

roles/matrix-riot-web/defaults/main.yml

@@ -43,3 +43,36 @@ matrix_riot_web_registration_enabled: false
 
 # Controls whether Riot shows the presence features
 matrix_riot_web_enable_presence_by_hs_url: ~
+
+# Default riot-web configuration template which covers the generic use case.
+# You can customize it by controlling the various variables inside it.
+#
+# For a more advanced customization, you can extend the default (see `matrix_riot_web_configuration_extension_json`)
+# or completely replace this variable with your own template.
+#
+# The side-effect of this lookup is that Ansible would even parse the JSON for us, returning a dict.
+# This is unlike what it does when looking up YAML template files (no automatic parsing there).
+matrix_riot_web_configuration_default: "{{ lookup('template', 'templates/config.json.j2') }}"
+
+# Your custom JSON configuration for riot-web should go to `matrix_riot_web_configuration_extension_json`.
+# This configuration extends the default starting configuration (`matrix_riot_web_configuration_default`).
+#
+# You can override individual variables from the default configuration, or introduce new ones.
+#
+# If you need something more special, you can take full control by
+# completely redefining `matrix_riot_web_configuration_default`.
+#
+# Example configuration extension follows:
+#
+# matrix_riot_web_configuration_extension_json: |
+#  {
+#  "disable_3pid_login": true,
+#  "disable_login_language_selector": true
+#  }
+matrix_riot_web_configuration_extension_json: '{}'
+
+matrix_riot_web_configuration_extension: "{{ matrix_riot_web_configuration_extension_json|from_json if matrix_riot_web_configuration_extension_json|from_json is mapping else {} }}"
+
+# Holds the final riot-web configuration (a combination of the default and its extension).
+# You most likely don't need to touch this variable. Instead, see `matrix_riot_web_configuration_default`.
+matrix_riot_web_configuration: "{{ matrix_riot_web_configuration_default|combine(matrix_riot_web_configuration_extension, recursive=True) }}"

roles/matrix-riot-web/tasks/setup_riot_web.yml

@@ -21,6 +21,14 @@
     force: "{{ omit if ansible_version.major > 2 or ansible_version.minor >= 8 else matrix_riot_web_docker_image_force_pull }}"
   when: matrix_riot_web_enabled|bool
 
+- name: Ensure Matrix riot-web configuration installed
+  copy:
+    content: "{{ matrix_riot_web_configuration|to_nice_json }}"
+    dest: "{{ matrix_riot_web_data_path }}/config.json"
+    mode: 0644
+    owner: "{{ matrix_user_username }}"
+    group: "{{ matrix_user_username }}"
+
 - name: Ensure Matrix riot-web config files installed
   template:
     src: "{{ item.src }}"
@@ -29,7 +37,6 @@
     owner: "{{ matrix_user_username }}"
     group: "{{ matrix_user_username }}"
   with_items:
-    - {src: "{{ role_path }}/templates/config.json.j2", name: "config.json"}
     - {src: "{{ role_path }}/templates/nginx.conf.j2", name: "nginx.conf"}
     - {src: "{{ role_path }}/templates/welcome.html.j2", name: "welcome.html"}
     - {src: "{{ matrix_riot_web_embedded_pages_home_path }}", name: "home.html"}

roles/matrix-riot-web/templates/config.json.j2

@@ -1,4 +1,3 @@
-#jinja2: lstrip_blocks: "True"
 {
 	"default_hs_url": {{ matrix_riot_web_default_hs_url|string|to_json }},
 	"default_is_url": {{ matrix_riot_web_default_is_url|string|to_json }},