add "delete all speakers" button (fixes #2210)

CHANGELOG

@@ -8,6 +8,9 @@ Version 2.1 (unreleased)
 ========================
 [https://github.com/OpenSlides/OpenSlides/milestones/2.1]
 
+Agenda: 
+- Added button to remove all speakers from a list of speakers.
+
 Core:
 - Used Django Channels instead of Tornado.
 - Added support for big assemblies with lots of users.

openslides/agenda/static/js/agenda/site.js

@@ -290,6 +290,26 @@ angular.module('OpenSlidesApp.agenda.site', ['OpenSlidesApp.agenda'])
             $scope.speakers = item.speakers;
         };
 
+        //delete all speakers from list of speakers
+        $scope.removeAllSpeakers = function () {
+            var speakersOnList = [];
+            angular.forEach(item.speakers, function (speaker) {
+                speakersOnList.push(speaker.id);
+            });
+            $http.delete(
+                '/rest/agenda/item/' + item.id + '/manage_speaker/',
+                {headers: {'Content-Type': 'application/json'},
+                 data: JSON.stringify({speaker: speakersOnList})}
+            )
+            .success(function(data){
+                $scope.speakers = item.speakers;
+            })
+            .error(function(data){
+                $scope.alert = { type: 'danger', msg: data.detail, show: true };
+            });
+            $scope.speakers = item.speakers;
+        };
+
         // check if user is allowed to see 'add me' / 'remove me' button
         $scope.isAllowed = function (action) {
             var nextUsers = [];

openslides/agenda/static/templates/agenda/item-detail.html

@@ -37,6 +37,12 @@
 <div ng-if="item" class="details listOfSpeakers">
   <div class="pull-right">
     <span os-perms="agenda.can_manage">
+      <button class="btn btn-danger"
+          ng-bootbox-confirm="{{ 'Are you sure you want to remove all speakers from this list?'| translate }}"
+          ng-bootbox-confirm-action="removeAllSpeakers()">
+          <i class="fa fa-trash fa-lg"></i>
+          <translate>Remove all speakers</translate>
+      </button>
       <button ng-if="item.speaker_list_closed" ng-click="closeList(false)"
           class="btn btn-sm btn-default">
         <i class="fa fa-toggle-off"></i>

openslides/agenda/views.py

@@ -81,8 +81,9 @@ class ItemViewSet(ListModelMixin, RetrieveModelMixin, UpdateModelMixin, GenericV
         """
         Special view endpoint to add users to the list of speakers or remove
         them. Send POST {'user': <user_id>} to add a new speaker. Omit
-        data to add yourself. Send DELETE {'speaker': <speaker_id>} to remove
+        data to add yourself. Send DELETE {'speaker': <speaker_id>} or
-        someone from the list of speakers. Omit data to remove yourself.
+        DELETE {'speaker': [<speaker_id>, <speaker_id>, ...]} to remove one or
+        more speakers from the list of speakers. Omit data to remove yourself.
 
         Checks also whether the requesting user can do this. He needs at
         least the permissions 'agenda.can_see' (see
@@ -126,11 +127,10 @@ class ItemViewSet(ListModelMixin, RetrieveModelMixin, UpdateModelMixin, GenericV
 
         else:
             # request.method == 'DELETE'
-            # Retrieve speaker_id
+            speaker_ids = request.data.get('speaker')
-            speaker_id = request.data.get('speaker')
 
             # Check permissions and other conditions. Get speaker instance.
-            if speaker_id is None:
+            if speaker_ids is None:
                 # Remove oneself
                 queryset = Speaker.objects.filter(
                     item=item, user=self.request.user).exclude(weight=None)
@@ -141,15 +141,20 @@ class ItemViewSet(ListModelMixin, RetrieveModelMixin, UpdateModelMixin, GenericV
                     speaker = queryset.get()
                 except Speaker.DoesNotExist:
                     raise ValidationError({'detail': _('You are not on the list of speakers.')})
+                else:
+                    speaker.delete()
+                    message = _('You are successfully removed from the list of speakers.')
             else:
                 # Remove someone else.
                 if not self.request.user.has_perm('agenda.can_manage'):
                     self.permission_denied(request)
+                if type(speaker_ids) is int:
+                    speaker_ids = [speaker_ids]
+                for speaker_id in speaker_ids:
                     try:
                         speaker = Speaker.objects.get(pk=int(speaker_id))
                     except (ValueError, Speaker.DoesNotExist):
                         raise ValidationError({'detail': _('Speaker does not exist.')})
-
                     # Delete the speaker.
                     speaker.delete()
                     message = _('Speaker %s was successfully removed from the list of speakers.') % speaker