xmpp: Display current domainname and example user ID.

plinth/modules/xmpp/templates/xmpp.html

@@ -31,6 +31,11 @@
   any other <a href='http://xmpp.org/xmpp-software/clients/' target='_blank'>
   XMPP client </a>.</p>
 
+<p>Your XMPP server domain is set to <b>{{ status.domainname }}</b>. User IDs
+  will look like <i>username@{{ status.domainname }}</i>. You can setup your
+  domain on the system <a href="{% url 'config:index' %}">Configure</a>
+  page.</p>
+
 <p><a href='/jwchat' target='_blank' class='btn btn-primary'> Launch web
   client</a></p>
 

plinth/modules/xmpp/views.py

@@ -34,10 +34,14 @@ from plinth.modules import xmpp
 logger = logging.getLogger(__name__)
 
 
+def get_domainname():
+    """Return the domainname"""
+    fqdn = socket.getfqdn()
+    return '.'.join(fqdn.split('.')[1:])
+
 def before_install():
     """Preseed debconf values before the packages are installed."""
-    fqdn = socket.getfqdn()
-    domainname = '.'.join(fqdn.split('.')[1:])
+    domainname = get_domainname()
     logger.info('XMPP service domainname - %s', domainname)
     actions.superuser_run('xmpp', ['pre-install', '--domainname', domainname])
 
@@ -74,7 +78,8 @@ def index(request):
 def get_status():
     """Get the current settings."""
     status = {'enabled': xmpp.is_enabled(),
-              'is_running': xmpp.is_running()}
+              'is_running': xmpp.is_running(),
+              'domainname': get_domainname()}
 
     return status