reduce multilevel object to plain variable

docs/configuring-playbook-synapse.md

@@ -27,8 +27,7 @@ matrix_synapse_password_config_enabled: true
 Add this to allow seamless forwarding to element web app and element android app. Without this setting matrix will ask the user if he trusts the app he tries to login.  
 
 ```yaml
-matrix_synapse_sso:
-  client_whitelist:
+matrix_synapse_sso_client_whitelist:
   - "https://element.{{ matrix_domain }}/"
   - element://element
 

roles/matrix-synapse/defaults/main.yml

@@ -463,6 +463,10 @@ matrix_synapse_oidc_config:
       display_name_template: "{{ matrix_synapse_oidc_display_name_template }}"
 
 # Set trusted SSO resources, e.g. [ "https://element.matrix.domain" ]
-matrix_synapse_sso:
-  client_whitelist: []
+matrix_synapse_sso_client_whitelist: |
+  {{
+    []
+    +
+    ([matrix_server_fqn_element, "element://element"] if matrix_client_element_enabled else [])
+  }}
 

roles/matrix-synapse/templates/synapse/homeserver.yaml.j2

@@ -1852,7 +1852,7 @@ sso:
     #
     # By default, this list is empty.
     #
-    client_whitelist: {{ matrix_synapse_sso.client_whitelist|to_json }}
+    client_whitelist: {{ matrix_synapse_sso_client_whitelist|to_json }}
     #  - https://riot.im/develop
     #  - https://my.custom.client/