ejabberd: add option to enable/disable Message Archive Management

actions/ejabberd

@@ -78,6 +78,13 @@ def parse_arguments():
         help='Update ejabberd with new domainname')
     domainname_change.add_argument('--domainname', help='New domainname')
 
+    # Switch/check Message Archive Management (MAM) in ejabberd config
+    help_MAM = 'Switch or check Message Archive Management (MAM).'
+    mam = subparsers.add_parser('mam', help=help_MAM)
+    mam.add_argument('command',
+                     choices=('enable', 'disable', 'status'),
+                     help=help_MAM)
+
     subparsers.required = True
     return parser.parse_args()
 
@@ -209,6 +216,52 @@ def subcommand_change_domainname(arguments):
     action_utils.service_start('ejabberd')
 
 
+def subcommand_mam(argument):
+    """Enable, disable, or get status of Message Archive Management (MAM)."""
+
+    with open(EJABBERD_CONFIG, 'r') as file_handle:
+        conf = ruamel.yaml.round_trip_load(file_handle, preserve_quotes=True)
+
+    if 'modules' not in conf:
+        print('Found no "modules" entry in ejabberd configuration file.')
+        return
+
+    if argument.command == 'status':
+        if 'mod_mam' in conf['modules']:
+            print('enabled')
+            return
+        else:
+            print('disabled')
+            return
+
+    if argument.command == 'enable':
+        # Explicitly set the recommended / default settings for mod_mam,
+        # see https://docs.ejabberd.im/admin/configuration/#mod-mam.
+        settings_mod_mam = {'mod_mam': {
+            'iqdisc': 'one_queue',  # discipline, recommended 'one_queue'
+            'db_type': 'mnesia',  # default is 'mnesia' (w/o set default_db)
+            'default': 'never',  # policy, default 'never'
+            'request_activates_archiving': False,  # default False
+            'assume_mam_usage': False,  # for non-ack'd msgs, default False
+            'cache_size': 1000,  # default is 1000 items
+            'cache_life_time': 3600  # default is 3600 seconds = 1h
+        }}
+        conf['modules'].update(settings_mod_mam)
+    elif argument.command == 'disable':
+        # disable modules by erasing from config file
+        if 'mod_mam' in conf['modules']:
+            conf['modules'].pop('mod_mam')
+    else:
+        print("Unknown command: %s" % argument.command)
+        return
+
+    with open(EJABBERD_CONFIG, 'w') as file_handle:
+        ruamel.yaml.round_trip_dump(conf, file_handle)
+
+    if action_utils.service_is_running('ejabberd'):
+        action_utils.service_restart('ejabberd')
+
+
 def main():
     """Parse arguments and perform all duties"""
     arguments = parse_arguments()

plinth/modules/ejabberd/forms.py

@@ -0,0 +1,40 @@
+#
+# This file is part of Plinth.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+
+"""
+Forms for configuring Ejabberd.
+"""
+
+from plinth import forms as plinthForms
+from django import forms as djangoForms
+from django.utils.translation import ugettext_lazy as _
+
+from plinth import cfg
+from plinth.utils import format_lazy
+
+
+class EjabberdForm(plinthForms.ServiceForm):
+    """Ejabberd configuration form."""
+    MAM_enabled = djangoForms.BooleanField(
+        label=_('Enable Message Archive Management'),
+        required=False,
+        help_text=format_lazy(_(
+            'If enabled, your {box_name} will store chat message histories. '
+            'This allows synchronization of conversations between multiple '
+            'clients, and reading the history of a multi-user chat room. '
+            'It depends on the client settings whether the histories are '
+            'stored as plain text or encrypted.'), box_name=_(cfg.box_name)))

plinth/modules/ejabberd/templates/ejabberd.html

@@ -19,6 +19,7 @@
 {% endcomment %}
 
 {% load i18n %}
+{% load bootstrap %}
 
 {% block description %}
 
@@ -46,3 +47,17 @@
       {% trans "Launch web client" %}</a>
   </p>
 {% endblock %}
+
+
+{% block configuration %}
+  <h3>{% trans "Configuration" %}</h3>
+
+  <form class="form" method="post">
+    {% csrf_token %}
+
+    {{ form|bootstrap }}
+
+    <input type="submit" class="btn btn-primary"
+           value="{% trans "Update setup" %}"/>
+  </form>
+{% endblock %}

plinth/modules/ejabberd/views.py

@@ -25,6 +25,10 @@ from stronghold.decorators import public
 
 from plinth.modules import ejabberd
 from plinth.views import ServiceView
+from .forms import EjabberdForm
+from plinth import actions
+from django.contrib import messages
+from django.utils.translation import ugettext as _
 
 
 class EjabberdServiceView(ServiceView):
@@ -33,8 +37,53 @@ class EjabberdServiceView(ServiceView):
     template_name = 'ejabberd.html'
     description = ejabberd.description
     diagnostics_module_name = 'ejabberd'
+    form_class = EjabberdForm
+
+    def get_initial(self):
+        initdict = super().get_initial()
+        initdict.update({'MAM_enabled': self.is_MAM_enabled()})
+        return initdict
 
     def get_context_data(self, *args, **kwargs):
+        """Add service to the context data."""
         context = super().get_context_data(*args, **kwargs)
         context['domainname'] = ejabberd.get_domainname()
         return context
+
+    def form_valid(self, form):
+        """Enable/disable a service and set messages."""
+        old_status = form.initial
+        new_status = form.cleaned_data
+        app_same = old_status['is_enabled'] == new_status['is_enabled']
+        mam_same = old_status['MAM_enabled'] == new_status['MAM_enabled']
+
+        if app_same and mam_same:
+            # TODO: find a more reliable/official way to check whether the
+            # request has messages attached.
+            if not self.request._messages._queued_messages:
+                messages.info(self.request, _('Setting unchanged'))
+        elif not app_same:
+            if new_status['is_enabled']:
+                self.service.enable()
+                messages.success(self.request, _('Application enabled'))
+            else:
+                self.service.disable()
+                messages.success(self.request, _('Application disabled'))
+
+        if not mam_same:
+            # note ejabberd action "enable" or "disable" restarts, if running
+            if new_status['MAM_enabled']:
+                actions.superuser_run('ejabberd', ['mam', 'enable'])
+                messages.success(self.request,
+                                 _('Message Archive Management enabled'))
+            else:
+                actions.superuser_run('ejabberd', ['mam', 'disable'])
+                messages.success(self.request,
+                                 _('Message Archive Management disabled'))
+
+        return super(ServiceView, self).form_valid(form)
+
+    def is_MAM_enabled(self):
+        """Return whether Message Archive Management (MAM) is enabled."""
+        output = actions.superuser_run('ejabberd', ['mam', 'status'])
+        return output.strip() == 'enabled'