create restore button basic functionality

src/c3nav/editor/models/change.py

@@ -258,6 +258,10 @@ class Change(models.Model):
                 return True
             return not getattr(current_obj, field.name).filter(pk=self.field_value).exists()
 
+    def restore(self, author):
+        if not self.can_restore:
+            return
+
     def save(self, *args, **kwargs):
         if self.pk is not None:
             raise TypeError('change objects can not be edited (use update to set discarded_by)')

src/c3nav/editor/templates/editor/changeset.html

@@ -16,6 +16,7 @@
         {% trans 'View History' %}
     </a>
 </p>
+{% bootstrap_messages %}
 
 {% include 'editor/fragment_change_groups.html' %}
 

src/c3nav/editor/templates/editor/changeset_history.html

@@ -4,6 +4,10 @@
 {% include 'editor/fragment_modal_close.html' %}
 <h3>{{ changeset.title }}</h3>
 <h4>{% trans 'Changeset History' %}</h4>
+<form method="post" action="{{ request.path }}">
+{% csrf_token %}
 <p><a href="{% url 'editor.changesets.detail' pk=changeset.pk %}">« {% trans 'back to changeset' %}</a></p>
+{% bootstrap_messages %}
 
 {% include 'editor/fragment_change_groups.html' %}
+</form>

src/c3nav/editor/templates/editor/fragment_change_groups.html

@@ -36,9 +36,9 @@
                             <i class="glyphicon glyphicon-user text-muted" data-toggle="tooltip" data-placement="left" title="{{ change.author.username }}"></i>
                         {% endif %}
                         {% if change.can_restore %}
-                            <a class="btn btn-xs btn-default" data-toggle="tooltip" data-placement="left" title="{% trans 'Restore original state' %}">
+                            <button type="submit" name="restore" value="{{ change.pk }}" class="btn btn-xs btn-default" data-toggle="tooltip" data-placement="left" title="{% trans 'Restore original state' %}">
                                 <i class="glyphicon glyphicon-share-alt"></i>
-                            </a>
+                            </button>
                         {% endif %}
                         {% if change.created %}
                             <i class="glyphicon glyphicon-time text-muted" data-toggle="tooltip" data-placement="left" title="{{ change.created }}"></i>

src/c3nav/editor/views/changes.py

@@ -2,6 +2,7 @@ import json
 from operator import itemgetter
 
 from django.conf import settings
+from django.contrib import messages
 from django.shortcuts import get_object_or_404, redirect, render
 from django.urls import reverse
 from django.utils.formats import date_format
@@ -23,6 +24,15 @@ def changeset_detail(request, pk, show_history=False):
 
     ctx = group_changes(changeset, can_edit=can_edit, show_history=show_history)
 
+    if request.method == 'POST':
+        restore = request.POST.get('restore')
+        if restore.isdigit():
+            change = changeset.changes.filter(pk=restore).first()
+            if change is not None and change.can_restore:
+                change.restore(request.user if request.user.is_authenticated else None)
+                messages.success(request, _('Original state has been restored!'))
+        return redirect(request.path)
+
     if show_history:
         return render(request, 'editor/changeset_history.html', ctx)