export_import: missing component in bundle (#88068)

chrono/apps/export_import/api_views.py

@@ -19,6 +19,7 @@ import json
 import tarfile
 
 from django.contrib.auth.models import Group
+from django.contrib.contenttypes.models import ContentType
 from django.http import Http404
 from django.shortcuts import get_object_or_404, redirect
 from django.urls import reverse
@@ -42,6 +43,14 @@ klasses_translation = {
 }
 klasses_translation_reverse = {v: k for k, v in klasses_translation.items()}
 
+compare_urls = {
+    'agendas': 'chrono-manager-agenda-history-compare',
+    'categories': 'chrono-manager-category-history-compare',
+    'events_types': 'chrono-manager-events-type-history-compare',
+    'resources': 'chrono-manager-resource-history-compare',
+    'unavailability_calendars': 'chrono-manager-unavailability-calendar-history-compare',
+}
+
 
 def get_klass_from_component_type(component_type):
     try:
@@ -191,6 +200,27 @@ component_dependencies = ComponentDependencies.as_view()
 def component_redirect(request, component_type, slug):
     klass = get_klass_from_component_type(component_type)
     component = get_object_or_404(klass, slug=slug)
+
+    if component_type not in klasses or component_type == 'roles':
+        raise Http404
+
+    if (
+        'compare' in request.GET
+        and request.GET.get('application')
+        and request.GET.get('version1')
+        and request.GET.get('version2')
+    ):
+        component_type = klasses_translation.get(component_type, component_type)
+        return redirect(
+            '%s?version1=%s&version2=%s&application=%s'
+            % (
+                reverse(compare_urls[component_type], args=[component.pk]),
+                request.GET['version1'],
+                request.GET['version2'],
+                request.GET['application'],
+            )
+        )
+
     if klass == Agenda:
         return redirect(reverse('chrono-manager-agenda-view', kwargs={'pk': component.pk}))
     if klass == Category:
@@ -201,6 +231,7 @@ def component_redirect(request, component_type, slug):
         return redirect(reverse('chrono-manager-resource-view', kwargs={'pk': component.pk}))
     if klass == UnavailabilityCalendar:
         return redirect(reverse('chrono-manager-unavailability-calendar-view', kwargs={'pk': component.pk}))
+
     raise Http404
 
 
@@ -208,7 +239,113 @@ class BundleCheck(GenericAPIView):
     permission_classes = (permissions.IsAuthenticatedOrReadOnly,)
 
     def put(self, request, *args, **kwargs):
-        return Response({'err': 0, 'data': {}})
+        tar_io = io.BytesIO(request.read())
+        try:
+            with tarfile.open(fileobj=tar_io) as tar:
+                try:
+                    manifest = json.loads(tar.extractfile('manifest.json').read().decode())
+                except KeyError:
+                    raise APIError(_('Invalid tar file, missing manifest'))
+                application_slug = manifest.get('slug')
+                application_version = manifest.get('version_number')
+                if not application_slug or not application_version:
+                    return Response({'data': {}})
+
+                differences = []
+                unknown_elements = []
+                no_history_elements = []
+                legacy_elements = []
+                content_types = ContentType.objects.get_for_models(
+                    *[v for k, v in klasses.items() if k != 'roles']
+                )
+                for element in manifest.get('elements'):
+                    component_type = element['type']
+                    if component_type not in klasses or component_type == 'roles':
+                        continue
+                    klass = klasses[component_type]
+                    component_type = klasses_translation.get(component_type, component_type)
+                    try:
+                        component = klass.objects.get(slug=element['slug'])
+                    except klass.DoesNotExist:
+                        unknown_elements.append(
+                            {
+                                'type': component_type,
+                                'slug': element['slug'],
+                            }
+                        )
+                        continue
+                    elements_qs = ApplicationElement.objects.filter(
+                        application__slug=application_slug,
+                        content_type=content_types[klass],
+                        object_id=component.pk,
+                    )
+                    if not elements_qs.exists():
+                        # object exists, but not linked to the application
+                        legacy_elements.append(
+                            {
+                                'type': component.application_component_type,
+                                'slug': str(component.slug),
+                                # information needed here, Relation objects may not exist yet in hobo
+                                'text': component.label,
+                                'url': reverse(
+                                    'api-export-import-component-redirect',
+                                    kwargs={
+                                        'slug': str(component.slug),
+                                        'component_type': component.application_component_type,
+                                    },
+                                ),
+                            }
+                        )
+                        continue
+                    snapshot_for_app = (
+                        klass.get_snapshot_model()
+                        .objects.filter(
+                            instance=component,
+                            application_slug=application_slug,
+                            application_version=application_version,
+                        )
+                        .order_by('timestamp')
+                        .last()
+                    )
+                    if not snapshot_for_app:
+                        # no snapshot for this bundle
+                        no_history_elements.append(
+                            {
+                                'type': element['type'],
+                                'slug': element['slug'],
+                            }
+                        )
+                        continue
+                    last_snapshot = (
+                        klass.get_snapshot_model().objects.filter(instance=component).latest('timestamp')
+                    )
+                    if snapshot_for_app.pk != last_snapshot.pk:
+                        differences.append(
+                            {
+                                'type': element['type'],
+                                'slug': element['slug'],
+                                'url': '%s%s?version1=%s&version2=%s'
+                                % (
+                                    request.build_absolute_uri('/')[:-1],
+                                    reverse(compare_urls[component_type], args=[component.pk]),
+                                    snapshot_for_app.pk,
+                                    last_snapshot.pk,
+                                ),
+                            }
+                        )
+        except tarfile.TarError:
+            raise APIError(_('Invalid tar file'))
+
+        return Response(
+            {
+                'data': {
+                    'differences': differences,
+                    'unknown_elements': unknown_elements,
+                    'no_history_elements': no_history_elements,
+                    'legacy_elements': legacy_elements,
+                }
+            }
+        )
 
 
 bundle_check = BundleCheck.as_view()
@@ -283,6 +420,11 @@ class BundleImport(GenericAPIView):
                         self.application, existing_component
                     )
                     self.application_elements.add(element.content_object)
+                    if self.install is True:
+                        existing_component.take_snapshot(
+                            comment=_('Application (%s)') % self.application,
+                            application=self.application,
+                        )
 
     def unlink_obsolete_objects(self):
         known_elements = ApplicationElement.objects.filter(application=self.application)

chrono/apps/snapshot/models.py

@@ -40,7 +40,7 @@ class WithSnapshotMixin:
         return cls._meta.get_field('snapshot').related_model
 
     def take_snapshot(self, *args, **kwargs):
-        self.get_snapshot_model().take(self, *args, **kwargs)
+        return self.get_snapshot_model().take(self, *args, **kwargs)
 
 
 class AbstractSnapshot(models.Model):
@@ -74,6 +74,7 @@ class AbstractSnapshot(models.Model):
             snapshot.application_slug = application.slug
             snapshot.application_version = application.version_number
         snapshot.save()
+        return snapshot
 
     def get_instance(self):
         try:
@@ -85,6 +86,54 @@ class AbstractSnapshot(models.Model):
     def load_instance(self, json_instance, snapshot=None):
         return self.get_instance_model().import_json(json_instance, snapshot=snapshot)[1]
 
+    def load_history(self):
+        if self.instance is None:
+            self._history = []
+            return
+        history = type(self).objects.filter(instance=self.instance)
+        self._history = [s.id for s in history]
+
+    @property
+    def previous(self):
+        if not hasattr(self, '_history'):
+            self.load_history()
+
+        try:
+            idx = self._history.index(self.id)
+        except ValueError:
+            return None
+        if idx == 0:
+            return None
+        return self._history[idx - 1]
+
+    @property
+    def next(self):
+        if not hasattr(self, '_history'):
+            self.load_history()
+
+        try:
+            idx = self._history.index(self.id)
+        except ValueError:
+            return None
+        try:
+            return self._history[idx + 1]
+        except IndexError:
+            return None
+
+    @property
+    def first(self):
+        if not hasattr(self, '_history'):
+            self.load_history()
+
+        return self._history[0]
+
+    @property
+    def last(self):
+        if not hasattr(self, '_history'):
+            self.load_history()
+
+        return self._history[-1]
+
 
 class AgendaSnapshot(AbstractSnapshot):
     instance = models.ForeignKey(

chrono/apps/snapshot/views.py

@@ -0,0 +1,150 @@
+# chrono - agendas system
+# Copyright (C) 2016-2024  Entr'ouvert
+#
+# 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/>.
+
+import difflib
+import json
+
+from django.http import Http404, HttpResponseRedirect
+from django.shortcuts import get_object_or_404, redirect
+from django.urls import reverse
+from django.utils.formats import date_format
+from django.utils.translation import gettext_lazy as _
+from django.views.generic import DetailView, ListView
+
+from chrono.utils.timezone import localtime
+
+
+class InstanceWithSnapshotHistoryView(ListView):
+    def get_queryset(self):
+        self.instance = get_object_or_404(self.model.get_instance_model(), pk=self.kwargs['pk'])
+        return self.instance.instance_snapshots.all().select_related('user')
+
+    def get_context_data(self, **kwargs):
+        kwargs[self.instance_context_key] = self.instance
+        kwargs['object'] = self.instance
+        current_date = None
+        context = super().get_context_data(**kwargs)
+        day_snapshot = None
+        for snapshot in context['object_list']:
+            if snapshot.timestamp.date() != current_date:
+                current_date = snapshot.timestamp.date()
+                snapshot.new_day = True
+                snapshot.day_other_count = 0
+                day_snapshot = snapshot
+            else:
+                day_snapshot.day_other_count += 1
+        return context
+
+
+class InstanceWithSnapshotHistoryCompareView(DetailView):
+    def get_snapshots_from_application(self):
+        version1 = self.request.GET.get('version1')
+        version2 = self.request.GET.get('version2')
+        if not version1 or not version2:
+            raise Http404
+
+        snapshot_for_app1 = (
+            self.model.get_snapshot_model()
+            .objects.filter(
+                instance=self.object,
+                application_slug=self.request.GET['application'],
+                application_version=self.request.GET['version1'],
+            )
+            .order_by('timestamp')
+            .last()
+        )
+        snapshot_for_app2 = (
+            self.model.get_snapshot_model()
+            .objects.filter(
+                instance=self.object,
+                application_slug=self.request.GET['application'],
+                application_version=self.request.GET['version2'],
+            )
+            .order_by('timestamp')
+            .last()
+        )
+        return snapshot_for_app1, snapshot_for_app2
+
+    def get_snapshots(self):
+        if 'application' in self.request.GET:
+            return self.get_snapshots_from_application()
+
+        id1 = self.request.GET.get('version1')
+        id2 = self.request.GET.get('version2')
+        if not id1 or not id2:
+            raise Http404
+
+        snapshot1 = get_object_or_404(self.model.get_snapshot_model(), pk=id1, instance=self.object)
+        snapshot2 = get_object_or_404(self.model.get_snapshot_model(), pk=id2, instance=self.object)
+
+        return snapshot1, snapshot2
+
+    def get_context_data(self, **kwargs):
+        kwargs[self.instance_context_key] = self.object
+
+        mode = self.request.GET.get('mode') or 'json'
+        if mode not in ['json']:
+            raise Http404
+
+        snapshot1, snapshot2 = self.get_snapshots()
+        if not snapshot1 or not snapshot2:
+            return redirect(reverse(self.history_view, args=[self.object.pk]))
+        if snapshot1.timestamp > snapshot2.timestamp:
+            snapshot1, snapshot2 = snapshot2, snapshot1
+
+        kwargs['mode'] = mode
+        kwargs['snapshot1'] = snapshot1
+        kwargs['snapshot2'] = snapshot2
+        kwargs['fromdesc'] = self.get_snapshot_desc(snapshot1)
+        kwargs['todesc'] = self.get_snapshot_desc(snapshot2)
+        kwargs.update(getattr(self, 'get_compare_%s_context' % mode)(snapshot1, snapshot2))
+
+        return super().get_context_data(**kwargs)
+
+    def get(self, request, *args, **kwargs):
+        self.object = self.get_object()
+        context = self.get_context_data(object=self.object)
+        if isinstance(context, HttpResponseRedirect):
+            return context
+        return self.render_to_response(context)
+
+    def get_compare_json_context(self, snapshot1, snapshot2):
+        s1 = json.dumps(snapshot1.serialization, sort_keys=True, indent=2)
+        s2 = json.dumps(snapshot2.serialization, sort_keys=True, indent=2)
+        diff_serialization = difflib.HtmlDiff(wrapcolumn=160).make_table(
+            fromlines=s1.splitlines(True),
+            tolines=s2.splitlines(True),
+        )
+
+        return {
+            'diff_serialization': diff_serialization,
+        }
+
+    def get_snapshot_desc(self, snapshot):
+        label_or_comment = ''
+        if snapshot.label:
+            label_or_comment = snapshot.label
+        elif snapshot.comment:
+            label_or_comment = snapshot.comment
+        if snapshot.application_version:
+            label_or_comment += ' (%s)' % _('Version %s') % snapshot.application_version
+        return '{name} ({pk}) - {label_or_comment} ({user}{timestamp})'.format(
+            name=_('Snapshot'),
+            pk=snapshot.id,
+            label_or_comment=label_or_comment,
+            user='%s ' % snapshot.user if snapshot.user_id else '',
+            timestamp=date_format(localtime(snapshot.timestamp), format='DATETIME_FORMAT'),
+        )

chrono/manager/static/css/style.scss

@@ -956,3 +956,54 @@ a.button.button-paragraph {
 .application-logo, .application-icon {
 	vertical-align: middle;
 }
+
+.snapshots-list .collapsed {
+	display: none;
+}
+
+p.snapshot-description {
+	font-size: 80%;
+	margin: 0;
+}
+
+table.diff {
+	background: white;
+	border: 1px solid #f3f3f3;
+	border-collapse: collapse;
+	width: 100%;
+	colgroup, thead, tbody, td {
+		border: 1px solid #f3f3f3;
+	}
+	tbody tr:nth-child(even) {
+		background: #fdfdfd;
+	}
+	th, td {
+		max-width: 30vw;
+		/* it will not actually limit width as the table is set to
+		 * expand to 100% but it will prevent one side getting wider
+		 */
+		overflow: hidden;
+		text-overflow: ellipsis;
+		vertical-align: top;
+	}
+	.diff_header {
+		background: #f7f7f7;
+	}
+	td.diff_header {
+		text-align: right;
+		padding-right: 10px;
+		color: #606060;
+	}
+	.diff_next {
+		display: none;
+	}
+	.diff_add {
+		background-color: #aaffaa;
+	}
+	.diff_chg {
+		background-color: #ffff77;
+	}
+	.diff_sub {
+		background-color: #ffaaaa;
+	}
+}

chrono/manager/templates/chrono/includes/snapshot_compare_fragment.html

@@ -0,0 +1,20 @@
+<p class="snapshot-description">{{ fromdesc|safe }} ➔ {{ todesc|safe }}</p>
+<div class="diff">
+  {% if mode == 'json' %}
+    {{ diff_serialization|safe }}
+  {% else %}
+    <div class="{{ tab_class_names }}">
+      <div class="pk-tabs--tab-list" role="tablist">
+        {% for tab in tabs %}{{ tab|safe }}{% endfor %}
+        {{ tab_list|safe }}
+      </div>
+      <div class="pk-tabs--container">
+        {% for attrs, panel in panels %}
+          <div{% for k, v in attrs.items %} {{ k }}="{{ v }}"{% endfor %}>
+            {{ panel|safe }}
+          </div>
+        {% endfor %}
+      </div>
+    </div>
+  {% endif %}
+</div>

chrono/manager/templates/chrono/includes/snapshot_history_fragment.html

@@ -0,0 +1,63 @@
+{% load i18n %}
+<div>
+  <form action="{{ compare_url }}" method="get">
+    {% if object_list|length > 1 %}
+      <p><button>{% trans "Show differences" %}</button></p>
+    {% endif %}
+    <table class="main">
+      <thead>
+        <th>{% trans 'Identifier' %}</th>
+        <th>{% trans 'Compare' %}</th>
+        <th>{% trans 'Date' %}</th>
+        <th>{% trans 'Description' %}</th>
+        <th>{% trans 'User' %}</th>
+        <th>{% trans 'Actions' %}</th>
+      </thead>
+      <tbody class="snapshots-list">
+        {% for snapshot in object_list %}
+          <tr data-day="{{ snapshot.timestamp|date:"Y-m-d" }}" class="{% if snapshot.new_day %}new-day{% else %}collapsed{% endif %}">
+            <td><span class="counter">#{{ snapshot.pk }}</span></td>
+            <td>
+              {% if object_list|length > 1 %}
+                {% if not forloop.last %}<input type="radio" name="version1" value="{{ snapshot.pk }}" {% if forloop.first %}checked="checked"{% endif %} />{% else %}&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{% endif %}
+                {% if not forloop.first %}<input type="radio" name="version2" value="{{ snapshot.pk }}" {% if forloop.counter == 2 %}checked="checked"{% endif %}/>{% else %}&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{% endif %}
+              {% endif %}
+            </td>
+            <td>
+              {{ snapshot.timestamp }}
+              {% if snapshot.new_day and snapshot.day_other_count %} — <a class="reveal" href="#day-{{ snapshot.timestamp|date:"Y-m-d"}}">
+                {% if snapshot.day_other_count >= 50 %}<strong>{% endif %}
+                {% blocktrans trimmed count counter=snapshot.day_other_count %}
+                  1 other this day
+                {% plural %}
+                  {{ counter }} others
+                {% endblocktrans %}
+              {% endif %}
+            </td>
+            <td>
+              {% if snapshot.label %}
+                <strong>{{ snapshot.label }}</strong>
+              {% elif snapshot.comment %}
+                {{ snapshot.comment }}
+              {% endif %}
+              {% if snapshot.application_version %}({% blocktrans with version=snapshot.application_version %}Version {{ version }}{% endblocktrans %}){% endif %}
+            </td>
+            <td>{% if snapshot.user %} {{ snapshot.user.get_full_name }}{% endif %}</td>
+            <td>
+            </td>
+          </tr>
+        {% endfor %}
+      </tbody>
+    </table>
+  </form>
+</div>
+
+<script>
+  $(function() {
+    $('tr.new-day a.reveal').on('click', function() {
+      var day = $(this).parents('tr.new-day').data('day');
+      $('.snapshots-list tr[data-day="' + day + '"]:not(.new-day)').toggleClass('collapsed');
+      return false;
+    });
+  });
+</script>

chrono/manager/templates/chrono/manager_agenda_history.html

@@ -0,0 +1,19 @@
+{% extends "chrono/manager_agenda_settings.html" %}
+{% load i18n %}
+
+{% block appbar %}
+  <h2>{% trans 'Agenda history' %} - {{ agenda }}</h2>
+{% endblock %}
+
+{% block breadcrumb %}
+  {{ block.super }}
+  <a href="{% url 'chrono-manager-agenda-history' pk=agenda.pk %}">{% trans "History" %}</a>
+{% endblock %}
+
+{% block content %}
+  {% url 'chrono-manager-agenda-history-compare' pk=agenda.pk as compare_url %}
+  {% include 'chrono/includes/snapshot_history_fragment.html' %}
+{% endblock %}
+
+{% block sidebar %}
+{% endblock %}

chrono/manager/templates/chrono/manager_agenda_history_compare.html

@@ -0,0 +1,15 @@
+{% extends "chrono/manager_agenda_history.html" %}
+{% load i18n %}
+
+{% block appbar %}
+  <h2>{% trans 'Compare snapshots' %} ({% if mode == 'json' %}{% trans "JSON" %}{% else %}{% trans "Inspect" %}{% endif %})</h2>
+{% endblock %}
+
+{% block breadcrumb %}
+  {{ block.super }}
+  <a href="{% url 'chrono-manager-agenda-history-compare' pk=agenda.pk %}">{% trans "Compare snapshots" %}</a>
+{% endblock %}
+
+{% block content %}
+  {% include 'chrono/includes/snapshot_compare_fragment.html' %}
+{% endblock %}

chrono/manager/templates/chrono/manager_agenda_settings.html

@@ -120,6 +120,10 @@
       <a class="button button-paragraph" rel="popup" class="action-duplicate" href="{% url 'chrono-manager-agenda-duplicate' pk=object.pk %}">{% trans 'Duplicate' %}</a>
     {% endif %}
 
+    {% if show_history %}
+      <h3>{% trans "Navigation" %}</h3>
+      <a class="button button-paragraph" href="{% url 'chrono-manager-agenda-history' pk=agenda.pk %}">{% trans 'History' %}</a>
+    {% endif %}
     {% block agenda-extra-navigation-actions %}{% endblock %}
 
     {% url 'chrono-manager-homepage' as object_list_url %}

chrono/manager/templates/chrono/manager_category_form.html

@@ -20,6 +20,11 @@
   {% else %}
     <h2>{% trans "New Category" %}</h2>
   {% endif %}
+  {% if show_history and category %}
+    <span class="actions">
+      <a href="{% url 'chrono-manager-category-history' pk=category.pk %}">{% trans 'History' %}</a>
+    </span>
+  {% endif %}
 {% endblock %}
 
 {% block content %}

chrono/manager/templates/chrono/manager_category_history.html

@@ -0,0 +1,19 @@
+{% extends "chrono/manager_category_form.html" %}
+{% load i18n %}
+
+{% block appbar %}
+  <h2>{% trans 'Category history' %} - {{ category }}</h2>
+{% endblock %}
+
+{% block breadcrumb %}
+  {{ block.super }}
+  <a href="{% url 'chrono-manager-category-history' pk=category.pk %}">{% trans "History" %}</a>
+{% endblock %}
+
+{% block content %}
+  {% url 'chrono-manager-category-history-compare' pk=category.pk as compare_url %}
+  {% include 'chrono/includes/snapshot_history_fragment.html' %}
+{% endblock %}
+
+{% block sidebar %}
+{% endblock %}

chrono/manager/templates/chrono/manager_category_history_compare.html

@@ -0,0 +1,15 @@
+{% extends "chrono/manager_category_history.html" %}
+{% load i18n %}
+
+{% block appbar %}
+  <h2>{% trans 'Compare snapshots' %} ({% if mode == 'json' %}{% trans "JSON" %}{% else %}{% trans "Inspect" %}{% endif %})</h2>
+{% endblock %}
+
+{% block breadcrumb %}
+  {{ block.super }}
+  <a href="{% url 'chrono-manager-category-history-compare' pk=category.pk %}">{% trans "Compare snapshots" %}</a>
+{% endblock %}
+
+{% block content %}
+  {% include 'chrono/includes/snapshot_compare_fragment.html' %}
+{% endblock %}

chrono/manager/templates/chrono/manager_events_agenda_settings.html

@@ -8,7 +8,9 @@
 
 {% block agenda-extra-navigation-actions %}
   {% with lingo_url=object.get_lingo_url %}{% if lingo_url %}
-    <h3>{% trans "Navigation" %}</h3>
+    {% if not show_history %}
+      <h3>{% trans "Navigation" %}</h3>
+    {% endif %}
     <a class="button button-paragraph" href="{{ lingo_url }}">{% trans 'Pricing' context 'pricing' %}</a>
   {% endif %}{% endwith %}
 {% endblock %}

chrono/manager/templates/chrono/manager_events_type_form.html

@@ -20,6 +20,11 @@
   {% else %}
     <h2>{% trans "New events type" %}</h2>
   {% endif %}
+  {% if show_history and object.pk %}
+    <span class="actions">
+      <a href="{% url 'chrono-manager-events-type-history' pk=object.pk %}">{% trans 'History' %}</a>
+    </span>
+  {% endif %}
 {% endblock %}
 
 {% block content %}

chrono/manager/templates/chrono/manager_events_type_history.html

@@ -0,0 +1,19 @@
+{% extends "chrono/manager_events_type_form.html" %}
+{% load i18n %}
+
+{% block appbar %}
+  <h2>{% trans 'Events type history' %} - {{ events_type }}</h2>
+{% endblock %}
+
+{% block breadcrumb %}
+  {{ block.super }}
+  <a href="{% url 'chrono-manager-events-type-history' pk=events_type.pk %}">{% trans "History" %}</a>
+{% endblock %}
+
+{% block content %}
+  {% url 'chrono-manager-events-type-history-compare' pk=events_type.pk as compare_url %}
+  {% include 'chrono/includes/snapshot_history_fragment.html' %}
+{% endblock %}
+
+{% block sidebar %}
+{% endblock %}

chrono/manager/templates/chrono/manager_events_type_history_compare.html

@@ -0,0 +1,15 @@
+{% extends "chrono/manager_events_type_history.html" %}
+{% load i18n %}
+
+{% block appbar %}
+  <h2>{% trans 'Compare snapshots' %} ({% if mode == 'json' %}{% trans "JSON" %}{% else %}{% trans "Inspect" %}{% endif %})</h2>
+{% endblock %}
+
+{% block breadcrumb %}
+  {{ block.super }}
+  <a href="{% url 'chrono-manager-events-type-history-compare' pk=events_type.pk %}">{% trans "Compare snapshots" %}</a>
+{% endblock %}
+
+{% block content %}
+  {% include 'chrono/includes/snapshot_compare_fragment.html' %}
+{% endblock %}

chrono/manager/templates/chrono/manager_resource_detail.html

@@ -63,6 +63,11 @@
       <a class="button button-paragraph" rel="popup" href="{% url 'chrono-manager-resource-edit' pk=resource.pk %}">{% trans 'Edit' %}</a>
     {% endif %}
 
+    {% if show_history %}
+      <h3>{% trans "Navigation" %}</h3>
+      <a class="button button-paragraph" href="{% url 'chrono-manager-resource-history' pk=resource.pk %}">{% trans 'History' %}</a>
+    {% endif %}
+
     {% url 'chrono-manager-resource-list' as object_list_url %}
     {% include 'chrono/includes/application_detail_fragment.html' %}
   </aside>

chrono/manager/templates/chrono/manager_resource_history.html

@@ -0,0 +1,19 @@
+{% extends "chrono/manager_resource_detail.html" %}
+{% load i18n %}
+
+{% block appbar %}
+  <h2>{% trans 'Resource history' %} - {{ resource }}</h2>
+{% endblock %}
+
+{% block breadcrumb %}
+  {{ block.super }}
+  <a href="{% url 'chrono-manager-resource-history' pk=resource.pk %}">{% trans "History" %}</a>
+{% endblock %}
+
+{% block content %}
+  {% url 'chrono-manager-resource-history-compare' pk=resource.pk as compare_url %}
+  {% include 'chrono/includes/snapshot_history_fragment.html' %}
+{% endblock %}
+
+{% block sidebar %}
+{% endblock %}

chrono/manager/templates/chrono/manager_resource_history_compare.html

@@ -0,0 +1,15 @@
+{% extends "chrono/manager_resource_history.html" %}
+{% load i18n %}
+
+{% block appbar %}
+  <h2>{% trans 'Compare snapshots' %} ({% if mode == 'json' %}{% trans "JSON" %}{% else %}{% trans "Inspect" %}{% endif %})</h2>
+{% endblock %}
+
+{% block breadcrumb %}
+  {{ block.super }}
+  <a href="{% url 'chrono-manager-resource-history-compare' pk=resource.pk %}">{% trans "Compare snapshots" %}</a>
+{% endblock %}
+
+{% block content %}
+  {% include 'chrono/includes/snapshot_compare_fragment.html' %}
+{% endblock %}

chrono/manager/templates/chrono/manager_unavailability_calendar_history.html

@@ -0,0 +1,19 @@
+{% extends "chrono/manager_unavailability_calendar_settings.html" %}
+{% load i18n %}
+
+{% block appbar %}
+  <h2>{% trans 'UnavailabilityCalendarSnapshot calendar history' %} - {{ unavailability_calendar }}</h2>
+{% endblock %}
+
+{% block breadcrumb %}
+  {{ block.super }}
+  <a href="{% url 'chrono-manager-unavailability-calendar-history' pk=unavailability_calendar.pk %}">{% trans "History" %}</a>
+{% endblock %}
+
+{% block content %}
+  {% url 'chrono-manager-unavailability-calendar-history-compare' pk=unavailability_calendar.pk as compare_url %}
+  {% include 'chrono/includes/snapshot_history_fragment.html' %}
+{% endblock %}
+
+{% block sidebar %}
+{% endblock %}

chrono/manager/templates/chrono/manager_unavailability_calendar_history_compare.html

@@ -0,0 +1,15 @@
+{% extends "chrono/manager_unavailability_calendar_history.html" %}
+{% load i18n %}
+
+{% block appbar %}
+  <h2>{% trans 'Compare snapshots' %} ({% if mode == 'json' %}{% trans "JSON" %}{% else %}{% trans "Inspect" %}{% endif %})</h2>
+{% endblock %}
+
+{% block breadcrumb %}
+  {{ block.super }}
+  <a href="{% url 'chrono-manager-unavailability-calendar-history-compare' pk=unavailability_calendar.pk %}">{% trans "Compare snapshots" %}</a>
+{% endblock %}
+
+{% block content %}
+  {% include 'chrono/includes/snapshot_compare_fragment.html' %}
+{% endblock %}

chrono/manager/templates/chrono/manager_unavailability_calendar_settings.html

@@ -54,6 +54,11 @@
       <a class="button button-paragraph" rel="popup" href="{% url 'chrono-manager-unavailability-calendar-delete' pk=unavailability_calendar.id %}">{% trans 'Delete' %}</a>
     {% endif %}
 
+    {% if show_history %}
+      <h3>{% trans "Navigation" %}</h3>
+      <a class="button button-paragraph" href="{% url 'chrono-manager-unavailability-calendar-history' pk=unavailability_calendar.pk %}">{% trans 'History' %}</a>
+    {% endif %}
+
     {% url 'chrono-manager-unavailability-calendar-list' as object_list_url %}
     {% include 'chrono/includes/application_detail_fragment.html' %}
   </aside>

chrono/manager/urls.py

@@ -65,6 +65,16 @@ urlpatterns = [
         views.unavailability_calendar_import_unavailabilities,
         name='chrono-manager-unavailability-calendar-import-unavailabilities',
     ),
+    path(
+        'unavailability-calendar/<int:pk>/history/',
+        views.unavailability_calendar_history,
+        name='chrono-manager-unavailability-calendar-history',
+    ),
+    path(
+        'unavailability-calendar/<int:pk>/history/compare/',
+        views.unavailability_calendar_history_compare,
+        name='chrono-manager-unavailability-calendar-history-compare',
+    ),
     path('resources/', views.resource_list, name='chrono-manager-resource-list'),
     path('resource/add/', views.resource_add, name='chrono-manager-resource-add'),
     path('resource/<int:pk>/', views.resource_view, name='chrono-manager-resource-view'),
@@ -90,10 +100,22 @@ urlpatterns = [
     ),
     path('resource/<int:pk>/edit/', views.resource_edit, name='chrono-manager-resource-edit'),
     path('resource/<int:pk>/delete/', views.resource_delete, name='chrono-manager-resource-delete'),
+    path('resource/<int:pk>/history/', views.resource_history, name='chrono-manager-resource-history'),
+    path(
+        'resource/<int:pk>/history/compare/',
+        views.resource_history_compare,
+        name='chrono-manager-resource-history-compare',
+    ),
     path('categories/', views.category_list, name='chrono-manager-category-list'),
     path('category/add/', views.category_add, name='chrono-manager-category-add'),
     path('category/<int:pk>/edit/', views.category_edit, name='chrono-manager-category-edit'),
     path('category/<int:pk>/delete/', views.category_delete, name='chrono-manager-category-delete'),
+    path('category/<int:pk>/history/', views.category_history, name='chrono-manager-category-history'),
+    path(
+        'category/<int:pk>/history/compare/',
+        views.category_history_compare,
+        name='chrono-manager-category-history-compare',
+    ),
     path('events-types/', views.events_type_list, name='chrono-manager-events-type-list'),
     path('events-type/add/', views.events_type_add, name='chrono-manager-events-type-add'),
     path('events-type/<int:pk>/edit/', views.events_type_edit, name='chrono-manager-events-type-edit'),
@@ -102,6 +124,14 @@ urlpatterns = [
         views.events_type_delete,
         name='chrono-manager-events-type-delete',
     ),
+    path(
+        'events-type/<int:pk>/history/', views.events_type_history, name='chrono-manager-events-type-history'
+    ),
+    path(
+        'events-type/<int:pk>/history/compare/',
+        views.events_type_history_compare,
+        name='chrono-manager-events-type-history-compare',
+    ),
     path('agendas/add/', views.agenda_add, name='chrono-manager-agenda-add'),
     path('agendas/import/', views.agendas_import, name='chrono-manager-agendas-import'),
     path('agendas/export/', views.agendas_export, name='chrono-manager-agendas-export'),
@@ -449,6 +479,12 @@ urlpatterns = [
         views.agenda_import_events_sample_csv,
         name='chrono-manager-sample-events-csv',
     ),
+    path('agendas/<int:pk>/history/', views.agenda_history, name='chrono-manager-agenda-history'),
+    path(
+        'agendas/<int:pk>/history/compare/',
+        views.agenda_history_compare,
+        name='chrono-manager-agenda-history-compare',
+    ),
     path(
         'shared-custody/settings/',
         views.shared_custody_settings,

chrono/manager/views.py

@@ -92,6 +92,14 @@ from chrono.agendas.models import (
     VirtualMember,
 )
 from chrono.apps.export_import.models import Application
+from chrono.apps.snapshot.models import (
+    AgendaSnapshot,
+    CategorySnapshot,
+    EventsTypeSnapshot,
+    ResourceSnapshot,
+    UnavailabilityCalendarSnapshot,
+)
+from chrono.apps.snapshot.views import InstanceWithSnapshotHistoryCompareView, InstanceWithSnapshotHistoryView
 from chrono.utils.date import get_weekday_index
 from chrono.utils.timezone import localtime, make_aware, make_naive, now
 
@@ -288,6 +296,7 @@ class ResourceDetailView(DetailView):
     def get_context_data(self, **kwargs):
         context = super().get_context_data(**kwargs)
         context['resource'] = self.object
+        context['show_history'] = settings.SNAPSHOTS_ENABLED
         return context
 
 
@@ -791,6 +800,35 @@ class ResourceDeleteView(DeleteView):
 resource_delete = ResourceDeleteView.as_view()
 
 
+class ResourceHistoryView(InstanceWithSnapshotHistoryView):
+    template_name = 'chrono/manager_resource_history.html'
+    model = ResourceSnapshot
+    instance_context_key = 'resource'
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_staff:
+            raise PermissionDenied()
+        return super().dispatch(request, *args, **kwargs)
+
+
+resource_history = ResourceHistoryView.as_view()
+
+
+class ResourceHistoryCompareView(InstanceWithSnapshotHistoryCompareView):
+    template_name = 'chrono/manager_resource_history_compare.html'
+    model = Resource
+    instance_context_key = 'resource'
+    history_view = 'chrono-manager-resource-history'
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_staff:
+            raise PermissionDenied()
+        return super().dispatch(request, *args, **kwargs)
+
+
+resource_history_compare = ResourceHistoryCompareView.as_view()
+
+
 class CategoryListView(WithApplicationsMixin, ListView):
     template_name = 'chrono/manager_category_list.html'
     model = Category
@@ -852,6 +890,10 @@ class CategoryEditView(UpdateView):
         self.object.take_snapshot(request=self.request)
         return response
 
+    def get_context_data(self, **kwargs):
+        kwargs['show_history'] = settings.SNAPSHOTS_ENABLED
+        return super().get_context_data(**kwargs)
+
 
 category_edit = CategoryEditView.as_view()
 
@@ -876,6 +918,35 @@ class CategoryDeleteView(DeleteView):
 category_delete = CategoryDeleteView.as_view()
 
 
+class CategoryHistoryView(InstanceWithSnapshotHistoryView):
+    template_name = 'chrono/manager_category_history.html'
+    model = CategorySnapshot
+    instance_context_key = 'category'
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_staff:
+            raise PermissionDenied()
+        return super().dispatch(request, *args, **kwargs)
+
+
+category_history = CategoryHistoryView.as_view()
+
+
+class CategoryHistoryCompareView(InstanceWithSnapshotHistoryCompareView):
+    template_name = 'chrono/manager_category_history_compare.html'
+    model = Category
+    instance_context_key = 'category'
+    history_view = 'chrono-manager-category-history'
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_staff:
+            raise PermissionDenied()
+        return super().dispatch(request, *args, **kwargs)
+
+
+category_history_compare = CategoryHistoryCompareView.as_view()
+
+
 class EventsTypeListView(WithApplicationsMixin, ListView):
     template_name = 'chrono/manager_events_type_list.html'
     model = EventsType
@@ -934,6 +1005,7 @@ class EventsTypeEditView(UpdateView):
 
     def get_context_data(self, **kwargs):
         context = super().get_context_data(**kwargs)
+        context['show_history'] = settings.SNAPSHOTS_ENABLED
         data = None
         if self.request.method == 'POST':
             data = self.request.POST
@@ -1020,6 +1092,35 @@ class EventsTypeDeleteView(DeleteView):
 events_type_delete = EventsTypeDeleteView.as_view()
 
 
+class EventsTypeHistoryView(InstanceWithSnapshotHistoryView):
+    template_name = 'chrono/manager_events_type_history.html'
+    model = EventsTypeSnapshot
+    instance_context_key = 'events_type'
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_staff:
+            raise PermissionDenied()
+        return super().dispatch(request, *args, **kwargs)
+
+
+events_type_history = EventsTypeHistoryView.as_view()
+
+
+class EventsTypeHistoryCompareView(InstanceWithSnapshotHistoryCompareView):
+    template_name = 'chrono/manager_events_type_history_compare.html'
+    model = EventsType
+    instance_context_key = 'events_type'
+    history_view = 'chrono-manager-events-type-history'
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_staff:
+            raise PermissionDenied()
+        return super().dispatch(request, *args, **kwargs)
+
+
+events_type_history_compare = EventsTypeHistoryCompareView.as_view()
+
+
 class AgendaAddView(CreateView):
     template_name = 'chrono/manager_agenda_add_form.html'
     model = Agenda
@@ -2430,6 +2531,7 @@ class AgendaSettings(ManagedAgendaMixin, DetailView):
 
     def get_context_data(self, **kwargs):
         context = super().get_context_data(**kwargs)
+        context['show_history'] = settings.SNAPSHOTS_ENABLED
         if self.agenda.accept_meetings():
             context['meeting_types'] = self.object.iter_meetingtypes()
         if self.agenda.kind == 'virtual':
@@ -4052,6 +4154,35 @@ class TimePeriodExceptionSourceRefreshView(ManagedTimePeriodExceptionMixin, Deta
 time_period_exception_source_refresh = TimePeriodExceptionSourceRefreshView.as_view()
 
 
+class AgendaHistoryView(InstanceWithSnapshotHistoryView):
+    template_name = 'chrono/manager_agenda_history.html'
+    model = AgendaSnapshot
+    instance_context_key = 'agenda'
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_staff:
+            raise PermissionDenied()
+        return super().dispatch(request, *args, **kwargs)
+
+
+agenda_history = AgendaHistoryView.as_view()
+
+
+class AgendaHistoryCompareView(InstanceWithSnapshotHistoryCompareView):
+    template_name = 'chrono/manager_agenda_history_compare.html'
+    model = Agenda
+    instance_context_key = 'agenda'
+    history_view = 'chrono-manager-agenda-history'
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_staff:
+            raise PermissionDenied()
+        return super().dispatch(request, *args, **kwargs)
+
+
+agenda_history_compare = AgendaHistoryCompareView.as_view()
+
+
 class BookingCancelView(ViewableAgendaMixin, UpdateView):
     template_name = 'chrono/manager_confirm_booking_cancellation.html'
     model = Booking
@@ -4560,6 +4691,7 @@ class UnavailabilityCalendarSettings(ManagedUnavailabilityCalendarMixin, DetailV
     def get_context_data(self, **kwargs):
         context = super().get_context_data(**kwargs)
         context['unavailability_calendar'] = self.object
+        context['show_history'] = settings.SNAPSHOTS_ENABLED
         return context
 
 
@@ -4669,6 +4801,35 @@ class UnavailabilityCalendarImportUnavailabilitiesView(ManagedUnavailabilityCale
 unavailability_calendar_import_unavailabilities = UnavailabilityCalendarImportUnavailabilitiesView.as_view()
 
 
+class UnavailabilityCalendarHistoryView(InstanceWithSnapshotHistoryView):
+    template_name = 'chrono/manager_unavailability_calendar_history.html'
+    model = UnavailabilityCalendarSnapshot
+    instance_context_key = 'unavailability_calendar'
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_staff:
+            raise PermissionDenied()
+        return super().dispatch(request, *args, **kwargs)
+
+
+unavailability_calendar_history = UnavailabilityCalendarHistoryView.as_view()
+
+
+class UnavailabilityCalendarHistoryCompareView(InstanceWithSnapshotHistoryCompareView):
+    template_name = 'chrono/manager_unavailability_calendar_history_compare.html'
+    model = UnavailabilityCalendar
+    instance_context_key = 'unavailability_calendar'
+    history_view = 'chrono-manager-unavailability-calendar-history'
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_staff:
+            raise PermissionDenied()
+        return super().dispatch(request, *args, **kwargs)
+
+
+unavailability_calendar_history_compare = UnavailabilityCalendarHistoryCompareView.as_view()
+
+
 class SharedCustodyAgendaMixin:
     agenda = None
     tab_anchor = None

chrono/settings.py

@@ -206,6 +206,7 @@ REST_FRAMEWORK = {'EXCEPTION_HANDLER': 'chrono.api.utils.exception_handler'}
 
 SHARED_CUSTODY_ENABLED = False
 PARTIAL_BOOKINGS_ENABLED = False
+SNAPSHOTS_ENABLED = False
 
 CHRONO_ANTS_HUB_URL = None
 

tests/api/test_applification_api.py

@@ -9,6 +9,7 @@ from django.contrib.contenttypes.models import ContentType
 
 from chrono.agendas.models import Agenda, Category, Desk, EventsType, Resource, UnavailabilityCalendar
 from chrono.apps.export_import.models import Application, ApplicationElement
+from chrono.apps.snapshot.models import AgendaSnapshot
 
 pytestmark = pytest.mark.django_db
 
@@ -374,22 +375,57 @@ def test_redirect(app, user):
     redirect_url = f'/api/export-import/agendas/{agenda.slug}/redirect/'
     resp = app.get(redirect_url, status=302)
     assert resp.location == f'/manage/agendas/{agenda.pk}/'
+    resp = app.get(redirect_url + '?compare', status=302)
+    assert resp.location == f'/manage/agendas/{agenda.pk}/'
+    resp = app.get(redirect_url + '?compare&version1=bar&version2=bar&application=foo', status=302)
+    assert (
+        resp.location
+        == f'/manage/agendas/{agenda.pk}/history/compare/?version1=bar&version2=bar&application=foo'
+    )
 
     redirect_url = f'/api/export-import/agendas_categories/{category.slug}/redirect/'
     resp = app.get(redirect_url, status=302)
     assert resp.location == '/manage/categories/'
+    resp = app.get(redirect_url + '?compare', status=302)
+    assert resp.location == '/manage/categories/'
+    resp = app.get(redirect_url + '?compare&version1=bar&version2=bar&application=foo', status=302)
+    assert (
+        resp.location
+        == f'/manage/category/{category.pk}/history/compare/?version1=bar&version2=bar&application=foo'
+    )
 
     redirect_url = f'/api/export-import/resources/{resource.slug}/redirect/'
     resp = app.get(redirect_url, status=302)
     assert resp.location == f'/manage/resource/{resource.pk}/'
+    resp = app.get(redirect_url + '?compare', status=302)
+    assert resp.location == f'/manage/resource/{resource.pk}/'
+    resp = app.get(redirect_url + '?compare&version1=bar&version2=bar&application=foo', status=302)
+    assert (
+        resp.location
+        == f'/manage/resource/{resource.pk}/history/compare/?version1=bar&version2=bar&application=foo'
+    )
 
     redirect_url = f'/api/export-import/events_types/{events_type.slug}/redirect/'
     resp = app.get(redirect_url, status=302)
     assert resp.location == '/manage/events-types/'
+    resp = app.get(redirect_url + '?compare', status=302)
+    assert resp.location == '/manage/events-types/'
+    resp = app.get(redirect_url + '?compare&version1=bar&version2=bar&application=foo', status=302)
+    assert (
+        resp.location
+        == f'/manage/events-type/{events_type.pk}/history/compare/?version1=bar&version2=bar&application=foo'
+    )
 
     redirect_url = f'/api/export-import/unavailability_calendars/{unavailability_calendar.slug}/redirect/'
     resp = app.get(redirect_url, status=302)
     assert resp.location == f'/manage/unavailability-calendar/{unavailability_calendar.pk}/'
+    resp = app.get(redirect_url + '?compare', status=302)
+    assert resp.location == f'/manage/unavailability-calendar/{unavailability_calendar.pk}/'
+    resp = app.get(redirect_url + '?compare&version1=bar&version2=bar&application=foo', status=302)
+    assert (
+        resp.location
+        == f'/manage/unavailability-calendar/{unavailability_calendar.pk}/history/compare/?version1=bar&version2=bar&application=foo'
+    )
 
     # unknown component type
     app.get('/api/export-import/unknown/foo/redirect/', status=404)
@@ -509,6 +545,12 @@ def test_bundle_import(app, user):
     assert application.editable is False
     assert application.visible is True
     assert ApplicationElement.objects.count() == 8
+    for model in [Agenda, Category, EventsType, Resource, UnavailabilityCalendar]:
+        for instance in model.objects.all():
+            last_snapshot = model.get_snapshot_model().objects.filter(instance=instance).latest('pk')
+            assert last_snapshot.comment == 'Application (Test)'
+            assert last_snapshot.application_slug == 'test'
+            assert last_snapshot.application_version == '42.0'
 
     # check editable flag is kept on install
     application.editable = True
@@ -538,6 +580,12 @@ def test_bundle_import(app, user):
         ).exists()
         is False
     )
+    for model in [Agenda, Category, EventsType, Resource, UnavailabilityCalendar]:
+        for instance in model.objects.all():
+            last_snapshot = model.get_snapshot_model().objects.filter(instance=instance).latest('pk')
+            assert last_snapshot.comment == 'Application (Test)'
+            assert last_snapshot.application_slug == 'test'
+            assert last_snapshot.application_version == '42.1'
 
     # bad file format
     resp = app.put('/api/export-import/bundle-import/', b'garbage')
@@ -699,4 +747,283 @@ def test_bundle_unlink(app, user, bundle):
 
 def test_bundle_check(app, user):
     app.authorization = ('Basic', ('john.doe', 'password'))
-    assert app.put('/api/export-import/bundle-check/').json == {'err': 0, 'data': {}}
+
+    bundles = []
+    for version_number in ['42.0', '42.1']:
+        bundles.append(create_bundle(app, user, version_number=version_number))
+    Agenda.objects.all().delete()
+    Category.objects.all().delete()
+    Resource.objects.all().delete()
+    EventsType.objects.all().delete()
+    UnavailabilityCalendar.objects.all().delete()
+
+    incomplete_bundles = []
+    for manifest_json in [{'slug': 'test'}, {'version_number': '1.0'}]:
+        tar_io = io.BytesIO()
+        with tarfile.open(mode='w', fileobj=tar_io) as tar:
+            manifest_fd = io.BytesIO(json.dumps(manifest_json, indent=2).encode())
+            tarinfo = tarfile.TarInfo('manifest.json')
+            tarinfo.size = len(manifest_fd.getvalue())
+            tar.addfile(tarinfo, fileobj=manifest_fd)
+        incomplete_bundles.append(tar_io.getvalue())
+
+    # incorrect bundles, missing information
+    resp = app.put('/api/export-import/bundle-check/', incomplete_bundles[0])
+    assert resp.json == {'data': {}}
+    resp = app.put('/api/export-import/bundle-check/', incomplete_bundles[1])
+    assert resp.json == {'data': {}}
+
+    # not yet imported
+    resp = app.put('/api/export-import/bundle-check/', bundles[0])
+    assert resp.json == {
+        'data': {
+            'differences': [],
+            'no_history_elements': [],
+            'unknown_elements': [
+                {'slug': 'rdv', 'type': 'agendas'},
+                {'slug': 'foo', 'type': 'categories'},
+                {'slug': 'foo', 'type': 'resources'},
+                {'slug': 'foo', 'type': 'unavailability_calendars'},
+                {'slug': 'evt', 'type': 'agendas'},
+                {'slug': 'foo', 'type': 'events_types'},
+                {'slug': 'virt', 'type': 'agendas'},
+                {'slug': 'sub', 'type': 'agendas'},
+            ],
+            'legacy_elements': [],
+        }
+    }
+
+    # import bundle
+    resp = app.put('/api/export-import/bundle-import/', bundles[0])
+    assert Application.objects.count() == 1
+    assert ApplicationElement.objects.count() == 8
+
+    # remove application links
+    Application.objects.all().delete()
+    resp = app.put('/api/export-import/bundle-check/', bundles[0])
+    assert resp.json == {
+        'data': {
+            'differences': [],
+            'no_history_elements': [],
+            'unknown_elements': [],
+            'legacy_elements': [
+                {
+                    'slug': 'rdv',
+                    'text': 'Rdv',
+                    'type': 'agendas',
+                    'url': '/api/export-import/agendas/rdv/redirect/',
+                },
+                {
+                    'slug': 'foo',
+                    'text': 'Foo',
+                    'type': 'agendas_categories',
+                    'url': '/api/export-import/agendas_categories/foo/redirect/',
+                },
+                {
+                    'slug': 'foo',
+                    'text': 'Foo',
+                    'type': 'resources',
+                    'url': '/api/export-import/resources/foo/redirect/',
+                },
+                {
+                    'slug': 'foo',
+                    'text': 'Foo',
+                    'type': 'unavailability_calendars',
+                    'url': '/api/export-import/unavailability_calendars/foo/redirect/',
+                },
+                {
+                    'slug': 'evt',
+                    'text': 'Evt',
+                    'type': 'agendas',
+                    'url': '/api/export-import/agendas/evt/redirect/',
+                },
+                {
+                    'slug': 'foo',
+                    'text': 'Foo',
+                    'type': 'events_types',
+                    'url': '/api/export-import/events_types/foo/redirect/',
+                },
+                {
+                    'slug': 'virt',
+                    'text': 'Virt',
+                    'type': 'agendas',
+                    'url': '/api/export-import/agendas/virt/redirect/',
+                },
+                {
+                    'slug': 'sub',
+                    'text': 'Sub',
+                    'type': 'agendas',
+                    'url': '/api/export-import/agendas/sub/redirect/',
+                },
+            ],
+        }
+    }
+
+    # import bundle again, recreate links
+    resp = app.put('/api/export-import/bundle-import/', bundles[0])
+    assert Application.objects.count() == 1
+    assert ApplicationElement.objects.count() == 8
+
+    # no changes since last import
+    resp = app.put('/api/export-import/bundle-check/', bundles[0])
+    assert resp.json == {
+        'data': {
+            'differences': [],
+            'unknown_elements': [],
+            'no_history_elements': [],
+            'legacy_elements': [],
+        }
+    }
+
+    # add local changes
+    snapshots = {}
+    for model in [Agenda, Category, EventsType, Resource, UnavailabilityCalendar]:
+        for instance in model.objects.all():
+            old_snapshot = model.get_snapshot_model().objects.filter(instance=instance).latest('pk')
+            instance.take_snapshot(comment='local changes')
+            new_snapshot = model.get_snapshot_model().objects.filter(instance=instance).latest('pk')
+            assert new_snapshot.pk > old_snapshot.pk
+            snapshots[f'{instance.application_component_type}:{instance.slug}'] = (
+                instance.pk,
+                old_snapshot.pk,
+                new_snapshot.pk,
+            )
+
+    # and check
+    resp = app.put('/api/export-import/bundle-check/', bundles[0])
+    assert resp.json == {
+        'data': {
+            'differences': [
+                {
+                    'slug': 'rdv',
+                    'type': 'agendas',
+                    'url': 'http://testserver/manage/agendas/%s/history/compare/?version1=%s&version2=%s'
+                    % (
+                        snapshots['agendas:rdv'][0],
+                        snapshots['agendas:rdv'][1],
+                        snapshots['agendas:rdv'][2],
+                    ),
+                },
+                {
+                    'slug': 'foo',
+                    'type': 'agendas_categories',
+                    'url': 'http://testserver/manage/category/%s/history/compare/?version1=%s&version2=%s'
+                    % (
+                        snapshots['agendas_categories:foo'][0],
+                        snapshots['agendas_categories:foo'][1],
+                        snapshots['agendas_categories:foo'][2],
+                    ),
+                },
+                {
+                    'slug': 'foo',
+                    'type': 'resources',
+                    'url': 'http://testserver/manage/resource/%s/history/compare/?version1=%s&version2=%s'
+                    % (
+                        snapshots['resources:foo'][0],
+                        snapshots['resources:foo'][1],
+                        snapshots['resources:foo'][2],
+                    ),
+                },
+                {
+                    'slug': 'foo',
+                    'type': 'unavailability_calendars',
+                    'url': 'http://testserver/manage/unavailability-calendar/%s/history/compare/?version1=%s&version2=%s'
+                    % (
+                        snapshots['unavailability_calendars:foo'][0],
+                        snapshots['unavailability_calendars:foo'][1],
+                        snapshots['unavailability_calendars:foo'][2],
+                    ),
+                },
+                {
+                    'slug': 'evt',
+                    'type': 'agendas',
+                    'url': 'http://testserver/manage/agendas/%s/history/compare/?version1=%s&version2=%s'
+                    % (
+                        snapshots['agendas:evt'][0],
+                        snapshots['agendas:evt'][1],
+                        snapshots['agendas:evt'][2],
+                    ),
+                },
+                {
+                    'slug': 'foo',
+                    'type': 'events_types',
+                    'url': 'http://testserver/manage/events-type/%s/history/compare/?version1=%s&version2=%s'
+                    % (
+                        snapshots['events_types:foo'][0],
+                        snapshots['events_types:foo'][1],
+                        snapshots['events_types:foo'][2],
+                    ),
+                },
+                {
+                    'slug': 'virt',
+                    'type': 'agendas',
+                    'url': 'http://testserver/manage/agendas/%s/history/compare/?version1=%s&version2=%s'
+                    % (
+                        snapshots['agendas:virt'][0],
+                        snapshots['agendas:virt'][1],
+                        snapshots['agendas:virt'][2],
+                    ),
+                },
+                {
+                    'slug': 'sub',
+                    'type': 'agendas',
+                    'url': 'http://testserver/manage/agendas/%s/history/compare/?version1=%s&version2=%s'
+                    % (
+                        snapshots['agendas:sub'][0],
+                        snapshots['agendas:sub'][1],
+                        snapshots['agendas:sub'][2],
+                    ),
+                },
+            ],
+            'unknown_elements': [],
+            'no_history_elements': [],
+            'legacy_elements': [],
+        }
+    }
+
+    # update bundle
+    resp = app.put('/api/export-import/bundle-import/', bundles[1])
+
+    # and check
+    resp = app.put('/api/export-import/bundle-check/', bundles[1])
+    assert resp.json == {
+        'data': {
+            'differences': [],
+            'unknown_elements': [],
+            'no_history_elements': [],
+            'legacy_elements': [],
+        }
+    }
+
+    # snapshots without application info
+    AgendaSnapshot.objects.update(application_slug=None, application_version=None)
+    resp = app.put('/api/export-import/bundle-check/', bundles[1])
+    assert resp.json == {
+        'data': {
+            'differences': [],
+            'unknown_elements': [],
+            'no_history_elements': [
+                {'slug': 'rdv', 'type': 'agendas'},
+                {'slug': 'evt', 'type': 'agendas'},
+                {'slug': 'virt', 'type': 'agendas'},
+                {'slug': 'sub', 'type': 'agendas'},
+            ],
+            'legacy_elements': [],
+        }
+    }
+
+    # bad file format
+    resp = app.put('/api/export-import/bundle-check/', b'garbage')
+    assert resp.json['err']
+    assert resp.json['err_desc'] == 'Invalid tar file'
+
+    # missing manifest
+    tar_io = io.BytesIO()
+    with tarfile.open(mode='w', fileobj=tar_io) as tar:
+        foo_fd = io.BytesIO(json.dumps({'foo': 'bar'}, indent=2).encode())
+        tarinfo = tarfile.TarInfo('foo.json')
+        tarinfo.size = len(foo_fd.getvalue())
+        tar.addfile(tarinfo, fileobj=foo_fd)
+    resp = app.put('/api/export-import/bundle-check/', tar_io.getvalue())
+    assert resp.json['err']
+    assert resp.json['err_desc'] == 'Invalid tar file, missing manifest'

tests/manager/test_snapshot.py

@@ -0,0 +1,375 @@
+import datetime
+
+import pytest
+from django.utils.timezone import now
+
+from chrono.agendas.models import Agenda, Category, Desk, Event, EventsType, Resource, UnavailabilityCalendar
+from chrono.apps.snapshot.models import (
+    AgendaSnapshot,
+    CategorySnapshot,
+    EventsTypeSnapshot,
+    ResourceSnapshot,
+    UnavailabilityCalendarSnapshot,
+)
+from tests.utils import login
+
+pytestmark = pytest.mark.django_db
+
+
+def test_agenda_history(settings, app, admin_user):
+    agenda = Agenda.objects.create(slug='foo', label='Foo')
+    Desk.objects.create(agenda=agenda, slug='_exceptions_holder')
+    snapshot1 = agenda.take_snapshot()
+    Event.objects.create(
+        agenda=agenda,
+        places=1,
+        start_datetime=now() - datetime.timedelta(days=60),
+    )
+    agenda.description = 'Foo Bar'
+    agenda.save()
+    snapshot2 = agenda.take_snapshot()
+    snapshot2.application_slug = 'foobar'
+    snapshot2.application_version = '42.0'
+    snapshot2.save()
+    assert AgendaSnapshot.objects.count() == 2
+
+    app = login(app)
+    resp = app.get('/manage/agendas/%s/settings' % agenda.pk)
+    assert 'History' not in resp
+    settings.SNAPSHOTS_ENABLED = True
+    resp = app.get('/manage/agendas/%s/settings' % agenda.pk)
+    resp = resp.click('History')
+    assert [x.attrib['class'] for x in resp.pyquery.find('.snapshots-list tr')] == [
+        'new-day',
+        'collapsed',
+    ]
+    assert '(Version 42.0)' in resp.pyquery('tr:nth-child(1)').text()
+
+    resp = app.get(
+        '/manage/agendas/%s/history/compare/?version1=%s&version2=%s'
+        % (agenda.pk, snapshot1.pk, snapshot2.pk)
+    )
+    assert 'Snapshot (%s)' % (snapshot1.pk) in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % (snapshot2.pk) in resp
+    assert resp.text.count('diff_sub') == 1
+    assert resp.text.count('diff_add') == 16
+    assert resp.text.count('diff_chg') == 0
+    resp = app.get(
+        '/manage/agendas/%s/history/compare/?version1=%s&version2=%s'
+        % (agenda.pk, snapshot2.pk, snapshot1.pk)
+    )
+    assert 'Snapshot (%s)' % (snapshot1.pk) in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % (snapshot2.pk) in resp
+    assert resp.text.count('diff_sub') == 1
+    assert resp.text.count('diff_add') == 16
+    assert resp.text.count('diff_chg') == 0
+
+    # check compare on application version number
+    snapshot1.application_slug = 'foobar'
+    snapshot1.application_version = '41.0'
+    snapshot1.save()
+    # application not found
+    resp = app.get(
+        '/manage/agendas/%s/history/compare/?application=foobaz&version1=41.0&version2=42.0' % agenda.pk
+    )
+    assert resp.location == '/manage/agendas/%s/history/' % agenda.pk
+    # version1 not found
+    resp = app.get(
+        '/manage/agendas/%s/history/compare/?application=foobar&version1=40.0&version2=42.0' % agenda.pk
+    )
+    assert resp.location == '/manage/agendas/%s/history/' % agenda.pk
+    # version2 not found
+    resp = app.get(
+        '/manage/agendas/%s/history/compare/?application=foobar&version1=41.0&version2=43.0' % agenda.pk
+    )
+    assert resp.location == '/manage/agendas/%s/history/' % agenda.pk
+    # ok
+    resp = app.get(
+        '/manage/agendas/%s/history/compare/?application=foobar&version1=41.0&version2=42.0' % agenda.pk
+    )
+    assert 'Snapshot (%s) -  (Version 41.0)' % snapshot1.pk in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % snapshot2.pk in resp
+
+
+def test_category_history(settings, app, admin_user):
+    category = Category.objects.create(slug='foo', label='Foo')
+    snapshot1 = category.take_snapshot()
+    category.label = 'Bar'
+    category.save()
+    snapshot2 = category.take_snapshot()
+    snapshot2.application_slug = 'foobar'
+    snapshot2.application_version = '42.0'
+    snapshot2.save()
+    assert CategorySnapshot.objects.count() == 2
+
+    app = login(app)
+    resp = app.get('/manage/category/%s/edit/' % category.pk)
+    assert 'History' not in resp
+    settings.SNAPSHOTS_ENABLED = True
+    resp = app.get('/manage/category/%s/edit/' % category.pk)
+    resp = resp.click('History')
+    assert [x.attrib['class'] for x in resp.pyquery.find('.snapshots-list tr')] == [
+        'new-day',
+        'collapsed',
+    ]
+    assert '(Version 42.0)' in resp.pyquery('tr:nth-child(1)').text()
+
+    resp = app.get(
+        '/manage/category/%s/history/compare/?version1=%s&version2=%s'
+        % (category.pk, snapshot1.pk, snapshot2.pk)
+    )
+    assert 'Snapshot (%s)' % (snapshot1.pk) in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % (snapshot2.pk) in resp
+    assert resp.text.count('diff_sub') == 0
+    assert resp.text.count('diff_add') == 0
+    assert resp.text.count('diff_chg') == 2
+    resp = app.get(
+        '/manage/category/%s/history/compare/?version1=%s&version2=%s'
+        % (category.pk, snapshot2.pk, snapshot1.pk)
+    )
+    assert 'Snapshot (%s)' % (snapshot1.pk) in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % (snapshot2.pk) in resp
+    assert resp.text.count('diff_sub') == 0
+    assert resp.text.count('diff_add') == 0
+    assert resp.text.count('diff_chg') == 2
+
+    # check compare on application version number
+    snapshot1.application_slug = 'foobar'
+    snapshot1.application_version = '41.0'
+    snapshot1.save()
+    # application not found
+    resp = app.get(
+        '/manage/category/%s/history/compare/?application=foobaz&version1=41.0&version2=42.0' % category.pk
+    )
+    assert resp.location == '/manage/category/%s/history/' % category.pk
+    # version1 not found
+    resp = app.get(
+        '/manage/category/%s/history/compare/?application=foobar&version1=40.0&version2=42.0' % category.pk
+    )
+    assert resp.location == '/manage/category/%s/history/' % category.pk
+    # version2 not found
+    resp = app.get(
+        '/manage/category/%s/history/compare/?application=foobar&version1=41.0&version2=43.0' % category.pk
+    )
+    assert resp.location == '/manage/category/%s/history/' % category.pk
+    # ok
+    resp = app.get(
+        '/manage/category/%s/history/compare/?application=foobar&version1=41.0&version2=42.0' % category.pk
+    )
+    assert 'Snapshot (%s) -  (Version 41.0)' % snapshot1.pk in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % snapshot2.pk in resp
+
+
+def test_events_type_history(settings, app, admin_user):
+    events_type = EventsType.objects.create(slug='foo', label='Foo')
+    snapshot1 = events_type.take_snapshot()
+    events_type.label = 'Bar'
+    events_type.save()
+    snapshot2 = events_type.take_snapshot()
+    snapshot2.application_slug = 'foobar'
+    snapshot2.application_version = '42.0'
+    snapshot2.save()
+    assert EventsTypeSnapshot.objects.count() == 2
+
+    app = login(app)
+    resp = app.get('/manage/events-type/%s/edit/' % events_type.pk)
+    assert 'History' not in resp
+    settings.SNAPSHOTS_ENABLED = True
+    resp = app.get('/manage/events-type/%s/edit/' % events_type.pk)
+    resp = resp.click('History')
+    assert [x.attrib['class'] for x in resp.pyquery.find('.snapshots-list tr')] == [
+        'new-day',
+        'collapsed',
+    ]
+    assert '(Version 42.0)' in resp.pyquery('tr:nth-child(1)').text()
+
+    resp = app.get(
+        '/manage/events-type/%s/history/compare/?version1=%s&version2=%s'
+        % (events_type.pk, snapshot1.pk, snapshot2.pk)
+    )
+    assert 'Snapshot (%s)' % (snapshot1.pk) in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % (snapshot2.pk) in resp
+    assert resp.text.count('diff_sub') == 0
+    assert resp.text.count('diff_add') == 0
+    assert resp.text.count('diff_chg') == 2
+    resp = app.get(
+        '/manage/events-type/%s/history/compare/?version1=%s&version2=%s'
+        % (events_type.pk, snapshot2.pk, snapshot1.pk)
+    )
+    assert 'Snapshot (%s)' % (snapshot1.pk) in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % (snapshot2.pk) in resp
+    assert resp.text.count('diff_sub') == 0
+    assert resp.text.count('diff_add') == 0
+    assert resp.text.count('diff_chg') == 2
+
+    # check compare on application version number
+    snapshot1.application_slug = 'foobar'
+    snapshot1.application_version = '41.0'
+    snapshot1.save()
+    # application not found
+    resp = app.get(
+        '/manage/events-type/%s/history/compare/?application=foobaz&version1=41.0&version2=42.0'
+        % events_type.pk
+    )
+    assert resp.location == '/manage/events-type/%s/history/' % events_type.pk
+    # version1 not found
+    resp = app.get(
+        '/manage/events-type/%s/history/compare/?application=foobar&version1=40.0&version2=42.0'
+        % events_type.pk
+    )
+    assert resp.location == '/manage/events-type/%s/history/' % events_type.pk
+    # version2 not found
+    resp = app.get(
+        '/manage/events-type/%s/history/compare/?application=foobar&version1=41.0&version2=43.0'
+        % events_type.pk
+    )
+    assert resp.location == '/manage/events-type/%s/history/' % events_type.pk
+    # ok
+    resp = app.get(
+        '/manage/events-type/%s/history/compare/?application=foobar&version1=41.0&version2=42.0'
+        % events_type.pk
+    )
+    assert 'Snapshot (%s) -  (Version 41.0)' % snapshot1.pk in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % snapshot2.pk in resp
+
+
+def test_resource_history(settings, app, admin_user):
+    resource = Resource.objects.create(slug='foo', label='Foo')
+    snapshot1 = resource.take_snapshot()
+    resource.label = 'Bar'
+    resource.save()
+    snapshot2 = resource.take_snapshot()
+    snapshot2.application_slug = 'foobar'
+    snapshot2.application_version = '42.0'
+    snapshot2.save()
+    assert ResourceSnapshot.objects.count() == 2
+
+    app = login(app)
+    resp = app.get('/manage/resource/%s/' % resource.pk)
+    assert 'History' not in resp
+    settings.SNAPSHOTS_ENABLED = True
+    resp = app.get('/manage/resource/%s/' % resource.pk)
+    resp = resp.click('History')
+    assert [x.attrib['class'] for x in resp.pyquery.find('.snapshots-list tr')] == [
+        'new-day',
+        'collapsed',
+    ]
+    assert '(Version 42.0)' in resp.pyquery('tr:nth-child(1)').text()
+
+    resp = app.get(
+        '/manage/resource/%s/history/compare/?version1=%s&version2=%s'
+        % (resource.pk, snapshot1.pk, snapshot2.pk)
+    )
+    assert 'Snapshot (%s)' % (snapshot1.pk) in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % (snapshot2.pk) in resp
+    assert resp.text.count('diff_sub') == 0
+    assert resp.text.count('diff_add') == 0
+    assert resp.text.count('diff_chg') == 2
+    resp = app.get(
+        '/manage/resource/%s/history/compare/?version1=%s&version2=%s'
+        % (resource.pk, snapshot2.pk, snapshot1.pk)
+    )
+    assert 'Snapshot (%s)' % (snapshot1.pk) in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % (snapshot2.pk) in resp
+    assert resp.text.count('diff_sub') == 0
+    assert resp.text.count('diff_add') == 0
+    assert resp.text.count('diff_chg') == 2
+
+    # check compare on application version number
+    snapshot1.application_slug = 'foobar'
+    snapshot1.application_version = '41.0'
+    snapshot1.save()
+    # application not found
+    resp = app.get(
+        '/manage/resource/%s/history/compare/?application=foobaz&version1=41.0&version2=42.0' % resource.pk
+    )
+    assert resp.location == '/manage/resource/%s/history/' % resource.pk
+    # version1 not found
+    resp = app.get(
+        '/manage/resource/%s/history/compare/?application=foobar&version1=40.0&version2=42.0' % resource.pk
+    )
+    assert resp.location == '/manage/resource/%s/history/' % resource.pk
+    # version2 not found
+    resp = app.get(
+        '/manage/resource/%s/history/compare/?application=foobar&version1=41.0&version2=43.0' % resource.pk
+    )
+    assert resp.location == '/manage/resource/%s/history/' % resource.pk
+    # ok
+    resp = app.get(
+        '/manage/resource/%s/history/compare/?application=foobar&version1=41.0&version2=42.0' % resource.pk
+    )
+    assert 'Snapshot (%s) -  (Version 41.0)' % snapshot1.pk in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % snapshot2.pk in resp
+
+
+def test_unavailability_calendar_history(settings, app, admin_user):
+    unavailability_calendar = UnavailabilityCalendar.objects.create(slug='foo', label='Foo')
+    snapshot1 = unavailability_calendar.take_snapshot()
+    unavailability_calendar.label = 'Bar'
+    unavailability_calendar.save()
+    snapshot2 = unavailability_calendar.take_snapshot()
+    snapshot2.application_slug = 'foobar'
+    snapshot2.application_version = '42.0'
+    snapshot2.save()
+    assert UnavailabilityCalendarSnapshot.objects.count() == 2
+
+    app = login(app)
+    resp = app.get('/manage/unavailability-calendar/%s/settings' % unavailability_calendar.pk)
+    assert 'History' not in resp
+    settings.SNAPSHOTS_ENABLED = True
+    resp = app.get('/manage/unavailability-calendar/%s/settings' % unavailability_calendar.pk)
+    resp = resp.click('History')
+    assert [x.attrib['class'] for x in resp.pyquery.find('.snapshots-list tr')] == [
+        'new-day',
+        'collapsed',
+    ]
+    assert '(Version 42.0)' in resp.pyquery('tr:nth-child(1)').text()
+
+    resp = app.get(
+        '/manage/unavailability-calendar/%s/history/compare/?version1=%s&version2=%s'
+        % (unavailability_calendar.pk, snapshot1.pk, snapshot2.pk)
+    )
+    assert 'Snapshot (%s)' % (snapshot1.pk) in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % (snapshot2.pk) in resp
+    assert resp.text.count('diff_sub') == 0
+    assert resp.text.count('diff_add') == 0
+    assert resp.text.count('diff_chg') == 2
+    resp = app.get(
+        '/manage/unavailability-calendar/%s/history/compare/?version1=%s&version2=%s'
+        % (unavailability_calendar.pk, snapshot2.pk, snapshot1.pk)
+    )
+    assert 'Snapshot (%s)' % (snapshot1.pk) in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % (snapshot2.pk) in resp
+    assert resp.text.count('diff_sub') == 0
+    assert resp.text.count('diff_add') == 0
+    assert resp.text.count('diff_chg') == 2
+
+    # check compare on application version number
+    snapshot1.application_slug = 'foobar'
+    snapshot1.application_version = '41.0'
+    snapshot1.save()
+    # application not found
+    resp = app.get(
+        '/manage/unavailability-calendar/%s/history/compare/?application=foobaz&version1=41.0&version2=42.0'
+        % unavailability_calendar.pk
+    )
+    assert resp.location == '/manage/unavailability-calendar/%s/history/' % unavailability_calendar.pk
+    # version1 not found
+    resp = app.get(
+        '/manage/unavailability-calendar/%s/history/compare/?application=foobar&version1=40.0&version2=42.0'
+        % unavailability_calendar.pk
+    )
+    assert resp.location == '/manage/unavailability-calendar/%s/history/' % unavailability_calendar.pk
+    # version2 not found
+    resp = app.get(
+        '/manage/unavailability-calendar/%s/history/compare/?application=foobar&version1=41.0&version2=43.0'
+        % unavailability_calendar.pk
+    )
+    assert resp.location == '/manage/unavailability-calendar/%s/history/' % unavailability_calendar.pk
+    # ok
+    resp = app.get(
+        '/manage/unavailability-calendar/%s/history/compare/?application=foobar&version1=41.0&version2=42.0'
+        % unavailability_calendar.pk
+    )
+    assert 'Snapshot (%s) -  (Version 41.0)' % snapshot1.pk in resp
+    assert 'Snapshot (%s) -  (Version 42.0)' % snapshot2.pk in resp