AKDashboard/views.py

+from django.apps import apps
 from django.utils.decorators import method_decorator
 from django.views.decorators.csrf import ensure_csrf_cookie
-from django.views.generic import TemplateView
+from django.views.generic import TemplateView, DetailView
+from django.utils.translation import gettext_lazy as _
 
-from AKModel.models import Event
+from AKModel.models import Event, AK, AKSlot
+from AKPlanning import settings
 
 
 class DashboardView(TemplateView):
+    """
+    Index view of dashboard and therefore the main entry point for AKPlanning
+
+    Displays information and buttons for all public events
+    """
     template_name = 'AKDashboard/dashboard.html'
 
     @method_decorator(ensure_csrf_cookie)
@@ -14,5 +22,81 @@ class DashboardView(TemplateView):
 
     def get_context_data(self, **kwargs):
         context = super().get_context_data(**kwargs)
-        context['events'] = Event.objects.all()
+        # Load events and split between active and current/featured events and those that should show smaller below
+        context["active_and_current_events"] = []
+        context["old_events"] = []
+        events = Event.objects.filter(public=True).order_by("-active", "-pk").prefetch_related('dashboardbutton_set')
+        for event in events:
+            if event.active or len(context["active_and_current_events"]) < settings.DASHBOARD_MAX_FEATURED_EVENTS:
+                context["active_and_current_events"].append(event)
+            else:
+                context["old_events"].append(event)
+        context["active_event_count"] = len(context["active_and_current_events"])
+        context["old_event_count"] = len(context["old_events"])
+        context["total_event_count"] = context["active_event_count"] + context["old_event_count"]
+        return context
+
+
+class DashboardEventView(DetailView):
+    """
+    Dashboard view for a single event
+
+    In addition to the basic information and the buttons,
+    an overview over recent events (new and changed AKs, moved AKSlots) for the given event is shown.
+
+    The event dashboard also exists for non-public events (one only needs to know the URL/slug of the event).
+    """
+    template_name = 'AKDashboard/dashboard_event.html'
+    context_object_name = 'event'
+    model = Event
+
+    def get_context_data(self, **kwargs):
+        context = super().get_context_data(**kwargs)
+
+        # Show feed of recent changes (if activated)
+        if settings.DASHBOARD_SHOW_RECENT:
+            # Create a list of chronically sorted events (both AK and plan changes):
+            recent_changes = []
+
+            # Newest AKs (if AKSubmission is used)
+            if apps.is_installed("AKSubmission"):
+                # Get the latest x changes (if there are that many),
+                # where x corresponds to the entry threshold configured in the settings
+                # (such that the list will be completely filled even if there are no (newer) plan changes)
+                submission_changes = AK.history.filter(event=context['event'])[:int(settings.DASHBOARD_RECENT_MAX)] # pylint: disable=no-member, line-too-long
+                # Create textual representation including icons
+                for s in submission_changes:
+                    if s.history_type == '+':
+                        text = _('New AK: %(ak)s.') % {'ak': s.name}
+                        icon = ('plus-square', 'far')
+                    elif s.history_type == '~':
+                        text = _('AK "%(ak)s" edited.') % {'ak': s.name}
+                        icon = ('pen-square', 'fas')
+                    else:
+                        text = _('AK "%(ak)s" deleted.') % {'ak': s.name}
+                        icon = ('times', 'fas')
+
+                    # Store representation in change list (still unsorted)
+                    recent_changes.append(
+                        {'icon': icon, 'text': text, 'link': s.instance.detail_url, 'timestamp': s.history_date}
+                    )
+
+            # Changes in plan (if AKPlan is used and plan is publicly visible)
+            if apps.is_installed("AKPlan") and not context['event'].plan_hidden:
+                # Get the latest plan changes (again using a threshold, see above)
+                last_changed_slots = AKSlot.objects.select_related('ak').filter(event=context['event'], start__isnull=False).order_by('-updated')[:int(settings.DASHBOARD_RECENT_MAX)] #pylint: disable=line-too-long
+                for changed_slot in last_changed_slots:
+                    # Create textual representation including icons and links and store in list (still unsorted)
+                    recent_changes.append({'icon': ('clock', 'far'),
+                                           'text': _('AK "%(ak)s" (re-)scheduled.') % {'ak': changed_slot.ak.name},
+                                           'link': changed_slot.ak.detail_url,
+                                           'timestamp': changed_slot.updated})
+
+            # Sort by change date...
+            recent_changes.sort(key=lambda x: x['timestamp'], reverse=True)
+            # ... and restrict to the latest 25 changes
+            context['recent_changes'] = recent_changes[:int(settings.DASHBOARD_RECENT_MAX)]
+        else:
+            context['recent_changes'] = []
+
         return context

AKModel/apps.py

 from django.apps import AppConfig
+from django.contrib.admin.apps import AdminConfig
 
 
 class AkmodelConfig(AppConfig):
+    """
+    App configuration (default, only specifies name of the app)
+    """
     name = 'AKModel'
+
+
+class AKAdminConfig(AdminConfig):
+    """
+    App configuration for admin
+    Loading a custom version here allows to add additional contex and further adapt the behavior of the admin interface
+    """
+    default_site = 'AKModel.site.AKAdminSite'

AKModel/availability/forms.py

+# This part of the code was adapted from pretalx (https://github.com/pretalx/pretalx)
+# Copyright 2017-2019, Tobias Kunze
+# Original Copyrights licensed under the Apache License, Version 2.0 http://www.apache.org/licenses/LICENSE-2.0
+# Documentation was mainly added by us, other changes are marked in the code
+import datetime
+import json
+
+from django import forms
+from django.db import transaction
+from django.db.models.signals import post_save
+from django.utils.dateparse import parse_datetime
+from django.utils.translation import gettext_lazy as _
+
+from AKModel.availability.models import Availability
+from AKModel.availability.serializers import AvailabilitySerializer
+from AKModel.models import Event
+
+
+class AvailabilitiesFormMixin(forms.Form):
+    """
+    Mixin for forms to add availabilities functionality to it
+    Will handle the rendering and population of an availabilities field
+    """
+    availabilities = forms.CharField(
+        label=_('Availability'),
+        help_text=_(
+            'Click and drag to mark the availability during the event, double-click to delete. '
+            'Or use the start and end inputs to add entries to the calendar view.'  # Adapted help text
+        ),
+        widget=forms.TextInput(attrs={'class': 'availabilities-editor-data'}),
+        required=False,
+    )
+
+    def _serialize(self, event, instance):
+        """
+        Serialize relevant availabilities into a JSON format to populate the text field in the form
+
+        :param event: event the availabilities belong to (relevant for start and end times)
+        :param instance: the entity availabilities in this form should belong to (e.g., an AK, or a Room)
+        :return: JSON serializiation of the relevant availabilities
+        :rtype: str
+        """
+        if instance:
+            availabilities = AvailabilitySerializer(
+                instance.availabilities.all(), many=True
+            ).data
+        else:
+            availabilities = []
+
+        return json.dumps(
+            {
+                'availabilities': availabilities,
+                'event': {
+                    # 'timezone': event.timezone,
+                    'date_from': str(event.start),
+                    'date_to': str(event.end),
+                },
+            }
+        )
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        # Load event information and populate availabilities text field
+        self.event = self.initial.get('event')
+        if isinstance(self.event, int):
+            self.event = Event.objects.get(pk=self.event)
+        initial = kwargs.pop('initial', {})
+        initial['availabilities'] = self._serialize(self.event, kwargs['instance'])
+        if not isinstance(self, forms.BaseModelForm):
+            kwargs.pop('instance')
+        kwargs['initial'] = initial
+
+    def _parse_availabilities_json(self, jsonavailabilities):
+        """
+        Turn raw JSON availabilities into a list of model instances
+
+        :param jsonavailabilities: raw json input
+        :return: a list of availability objects corresponding to the raw input
+        :rtype: List[Availability]
+        """
+        try:
+            rawdata = json.loads(jsonavailabilities)
+        except ValueError as exc:
+            raise forms.ValidationError("Submitted availabilities are not valid json.") from exc
+        if not isinstance(rawdata, dict):
+            raise forms.ValidationError(
+                "Submitted json does not comply with expected format, should be object."
+            )
+        availabilities = rawdata.get('availabilities')
+        if not isinstance(availabilities, list):
+            raise forms.ValidationError(
+                "Submitted json does not comply with expected format, missing or malformed availabilities field"
+            )
+        return availabilities
+
+    def _parse_datetime(self, strdate):
+        """
+        Parse input date string
+        This will try to correct timezone information if needed
+
+        :param strdate: string representing a timestamp
+        :return: a timestamp object
+        """
+        tz = self.event.timezone  # adapt to our event model
+
+        obj = parse_datetime(strdate)
+        if not obj:
+            raise TypeError
+        if obj.tzinfo is None:
+            # Adapt to new python timezone interface
+            obj = obj.replace(tzinfo=tz)
+
+        return obj
+
+    def _validate_availability(self, rawavail):
+        """
+        Validate a raw availability instance input by making sure the relevant fields are present and can be parsed
+        The cleaned up values that are produced to test the validity of the input are stored in-place in the input
+        object for later usage in cleaning/parsing to availability objects
+
+        :param rawavail: object to validate/clean
+        """
+        message = _("The submitted availability does not comply with the required format.")
+        if not isinstance(rawavail, dict):
+            raise forms.ValidationError(message)
+        rawavail.pop('id', None)
+        rawavail.pop('allDay', None)
+        if not set(rawavail.keys()) == {'start', 'end'}:
+            raise forms.ValidationError(message)
+
+        try:
+            rawavail['start'] = self._parse_datetime(rawavail['start'])
+            rawavail['end'] = self._parse_datetime(rawavail['end'])
+        # Adapt: Better error handling
+        except (TypeError, ValueError) as exc:
+            raise forms.ValidationError(
+                _("The submitted availability contains an invalid date.")
+            ) from exc
+
+        timeframe_start = self.event.start  # adapt to our event model
+        if rawavail['start'] < timeframe_start:
+            rawavail['start'] = timeframe_start
+
+        # add 1 day, not 24 hours, https://stackoverflow.com/a/25427822/2486196
+        timeframe_end = self.event.end  # adapt to our event model
+        timeframe_end = timeframe_end + datetime.timedelta(days=1)
+        if rawavail['end'] > timeframe_end:
+            # If the submitted availability ended outside the event timeframe, fix it silently
+            rawavail['end'] = timeframe_end
+
+    def clean_availabilities(self):
+        """
+        Turn raw availabilities into real availability objects
+        :return:
+        """
+        data = self.cleaned_data.get('availabilities')
+        required = (
+                'availabilities' in self.fields and self.fields['availabilities'].required
+        )
+        if not data:
+            if required:
+                raise forms.ValidationError(_('Please fill in your availabilities!'))
+            return None
+
+        rawavailabilities = self._parse_availabilities_json(data)
+        availabilities = []
+
+        for rawavail in rawavailabilities:
+            self._validate_availability(rawavail)
+            availabilities.append(Availability(event_id=self.event.id, **rawavail))
+        if not availabilities and required:
+            raise forms.ValidationError(_('Please fill in your availabilities!'))
+        return availabilities
+
+    def _set_foreignkeys(self, instance, availabilities):
+        """
+        Set the reference to `instance` in each given availability.
+        For example, set the availabilitiy.room_id to instance.id, in
+        case instance of type Room.
+        """
+        reference_name = instance.availabilities.field.name + '_id'
+
+        for avail in availabilities:
+            setattr(avail, reference_name, instance.id)
+
+    def _replace_availabilities(self, instance, availabilities: list[Availability]):
+        """
+        Replace the existing list of availabilities belonging to an entity with a new, updated one
+
+        This will trigger a post_save signal for usage in constraint violation checking
+
+        :param instance: entity the availabilities belong to
+        :param availabilities: list of new availabilities
+        """
+        with transaction.atomic():
+            # TODO: do not recreate objects unnecessarily, give the client the IDs, so we can track modifications and
+            #  leave unchanged objects alone
+            instance.availabilities.all().delete()
+            Availability.objects.bulk_create(availabilities)
+            # Adaption:
+            # Trigger post save signal manually to make sure constraints are updated accordingly
+            # Doing this one time is sufficient, since this will nevertheless update all availability constraint
+            # violations of the corresponding AK
+            if len(availabilities) > 0:
+                post_save.send(Availability, instance=availabilities[0], created=True)
+
+    def save(self, *args, **kwargs):
+        """
+        Override the saving method of the (model) form
+        """
+        instance = super().save(*args, **kwargs)
+        availabilities = self.cleaned_data.get('availabilities')
+
+        if availabilities is not None:
+            self._set_foreignkeys(instance, availabilities)
+            self._replace_availabilities(instance, availabilities)
+
+        return instance  # adapt to our forms

AKModel/availability.py → AKModel/availability/models.py

@@ -21,8 +21,11 @@ zero_time = datetime.time(0, 0)
 # remove serialization as requirements are not covered
 # add translation
 # add meta class
-# enable availabilites for AKs and AKCategories
+# enable availabilities for AKs and AKCategories
 # add verbose names and help texts to model attributes
+# adapt or extemd documentation
+
+
 class Availability(models.Model):
     """The Availability class models when people or rooms are available for.
 
@@ -31,6 +34,8 @@ class Availability(models.Model):
     span multiple days, but due to our choice of input widget, it will
     usually only span a single day at most.
     """
+    # pylint: disable=broad-exception-raised
+
     event = models.ForeignKey(
         to=Event,
         related_name='availabilities',
@@ -96,10 +101,10 @@ class Availability(models.Model):
         are the same.
         """
         return all(
-            [
+            (
                 getattr(self, attribute, None) == getattr(other, attribute, None)
                 for attribute in ['event', 'person', 'room', 'ak', 'ak_category', 'start', 'end']
-            ]
+            )
         )
 
     @cached_property
@@ -146,9 +151,12 @@ class Availability(models.Model):
         if not other.overlaps(self, strict=False):
             raise Exception('Only overlapping Availabilities can be merged.')
 
-        return Availability(
+        avail = Availability(
             start=min(self.start, other.start), end=max(self.end, other.end)
         )
+        if self.event == other.event:
+            avail.event = self.event
+        return avail
 
     def __or__(self, other: 'Availability') -> 'Availability':
         """Performs the merge operation: ``availability1 | availability2``"""
@@ -163,9 +171,12 @@ class Availability(models.Model):
         if not other.overlaps(self, False):
             raise Exception('Only overlapping Availabilities can be intersected.')
 
-        return Availability(
+        avail = Availability(
             start=max(self.start, other.start), end=min(self.end, other.end)
         )
+        if self.event == other.event:
+            avail.event = self.event
+        return avail
 
     def __and__(self, other: 'Availability') -> 'Availability':
         """Performs the intersect operation: ``availability1 &
@@ -231,6 +242,68 @@ class Availability(models.Model):
             result = cls._pair_intersection(result, availset)
         return result
 
+    @property
+    def simplified(self):
+        """
+        Get a simplified (only Weekday, hour and minute) string representation of an availability
+        :return: simplified string version
+        :rtype: str
+        """
+        return (f'{self.start.astimezone(self.event.timezone).strftime("%a %H:%M")}-'
+                f'{self.end.astimezone(self.event.timezone).strftime("%a %H:%M")}')
+
+    @classmethod
+    def with_event_length(
+        cls,
+        event: Event,
+        person: AKOwner | None = None,
+        room: Room | None = None,
+        ak: AK | None = None,
+        ak_category: AKCategory | None = None,
+    ) -> "Availability":
+        """
+        Create an availability covering exactly the time between event start and event end.
+        Can e.g., be used to create default availabilities.
+
+        :param event: relevant event
+        :param person: person, if availability should be connected to a person
+        :param room: room, if availability should be connected to a room
+        :param ak: ak, if availability should be connected to a ak
+        :param ak_category: ak_category, if availability should be connected to a ak_category
+        :return: availability associated to the entity oder entities selected
+        :rtype: Availability
+        """
+        timeframe_start = event.start  # adapt to our event model
+        # add 1 day, not 24 hours, https://stackoverflow.com/a/25427822/2486196
+        timeframe_end = event.end  # adapt to our event model
+        timeframe_end = timeframe_end + datetime.timedelta(days=1)
+        return Availability(start=timeframe_start, end=timeframe_end, event=event, person=person,
+                                    room=room, ak=ak, ak_category=ak_category)
+
+    def is_covered(self, availabilities: List['Availability']):
+        """Check if list of availibilities cover this object.
+
+        :param availabilities: availabilities to check.
+        :return: whether the availabilities cover full event.
+        :rtype: bool
+        """
+        avail_union = Availability.union(availabilities)
+        return any(avail.contains(self) for avail in avail_union)
+
+    @classmethod
+    def is_event_covered(cls, event: Event, availabilities: List['Availability']) -> bool:
+        """Check if list of availibilities cover whole event.
+
+        :param event: event to check.
+        :param availabilities: availabilities to check.
+        :return: whether the availabilities cover full event.
+        :rtype: bool
+        """
+        # NOTE: Cannot use `Availability.with_event_length` as its end is the
+        #       event end + 1 day
+        full_event = Availability(event=event, start=event.start, end=event.end)
+        return full_event.is_covered(availabilities)
+
     class Meta:
         verbose_name = _('Availability')
         verbose_name_plural = _('Availabilities')

AKModel/availability/serializers.py

+# This part of the code was adapted from pretalx (https://github.com/pretalx/pretalx)
+# Copyright 2017-2019, Tobias Kunze
+# Original Copyrights licensed under the Apache License, Version 2.0 http://www.apache.org/licenses/LICENSE-2.0
+# Documentation was mainly added by us, other changes are marked in the code
+from django.utils import timezone
+from rest_framework.fields import SerializerMethodField
+from rest_framework.serializers import ModelSerializer
+
+from AKModel.availability.models import Availability
+
+
+class AvailabilitySerializer(ModelSerializer):
+    """
+    REST Framework Serializer for Availability
+    """
+    allDay = SerializerMethodField()
+    start = SerializerMethodField()
+    end = SerializerMethodField()
+
+    def get_allDay(self, obj):  # pylint: disable=invalid-name
+        """
+        Bridge between naming conventions of python and fullcalendar by providing the all_day field as allDay, too
+        """
+        return obj.all_day
+
+    def get_start(self, obj):
+        """
+        Get start timestamp
+
+        Use already localized strings in serialized field
+        (default would be UTC, but that would require heavy timezone calculation on client side)
+        """
+        return timezone.localtime(obj.start, obj.event.timezone).strftime("%Y-%m-%dT%H:%M:%S")
+
+    def get_end(self, obj):
+        """
+        Get end timestamp
+
+        Use already localized strings in serialized field
+        (default would be UTC, but that would require heavy timezone calculation on client side)
+        """
+        return timezone.localtime(obj.end, obj.event.timezone).strftime("%Y-%m-%dT%H:%M:%S")
+
+    class Meta:
+        model = Availability
+        fields = ('id', 'start', 'end', 'allDay')

AKModel/environment.py

+"""
+Environment definitions
+Needed for tex compilation
+"""
+import re
+
+from django_tex.environment import environment
+
+# Used to filter all very special UTF-8 chars that are probably not contained in the LaTeX fonts
+# and would hence cause compilation errors
+utf8_replace_pattern = re.compile('[^\u0000-\u206F]', re.UNICODE)
+
+
+def latex_escape_utf8(value):
+    """
+    Escape latex special chars and remove invalid utf-8 values
+
+    :param value: string to escape
+    :type value: str
+    :return: escaped string
+    :rtype: str
+    """
+    return (utf8_replace_pattern.sub('', value).replace('&', r'\&').replace('_', r'\_').replace('#', r'\#').
+            replace('$', r'\$').replace('%', r'\%').replace('{', r'\{').replace('}', r'\}'))
+
+
+def improved_tex_environment(**options):
+    """
+    Encapsulate our improved latex environment for usage
+    """
+    env = environment(**options)
+    env.filters.update({
+        'latex_escape_utf8': latex_escape_utf8,
+    })
+    return env

AKModel/fixtures/model.json

+[
+{
+    "model": "AKModel.event",
+    "pk": 1,
+    "fields": {
+        "name": "KIF 23",
+        "slug": "kif23",
+        "place": "Neuland",
+        "timezone": "Europe/Berlin",
+        "start": "2020-10-01T17:41:22Z",
+        "end": "2020-10-04T17:41:30Z",
+        "reso_deadline": "2020-10-03T10:00:00Z",
+        "interest_start": null,
+        "interest_end": null,
+        "public": true,
+        "active": false,
+        "plan_hidden": true,
+        "plan_published_at": null,
+        "base_url": "",
+        "wiki_export_template_name": "",
+        "default_slot": "2.00",
+        "contact_email": "dummy@eyample.org"
+    }
+},
+{
+    "model": "AKModel.event",
+    "pk": 2,
+    "fields": {
+        "name": "KIF 42",
+        "slug": "kif42",
+        "place": "Neuland noch neuer",
+        "timezone": "Europe/Berlin",
+        "start": "2020-11-06T17:51:26Z",
+        "end": "2020-11-10T17:51:27Z",
+        "reso_deadline": "2020-11-08T17:51:42Z",
+        "interest_start": null,
+        "interest_end": null,
+        "public": true,
+        "active": true,
+        "plan_hidden": false,
+        "plan_published_at": "2022-12-01T21:50:01Z",
+        "base_url": "",
+        "wiki_export_template_name": "",
+        "default_slot": "2.00",
+        "contact_email": "dummy@example.org"
+    }
+},
+{
+    "model": "AKModel.akowner",
+    "pk": 1,
+    "fields": {
+        "name": "a",
+        "slug": "a",
+        "institution": "Uni X",
+        "link": "",
+        "event": 2
+    }
+},
+{
+    "model": "AKModel.akowner",
+    "pk": 2,
+    "fields": {
+        "name": "b",
+        "slug": "b",
+        "institution": "Hochschule Y",
+        "link": "",
+        "event": 2
+    }
+},
+{
+    "model": "AKModel.akowner",
+    "pk": 3,
+    "fields": {
+        "name": "c",
+        "slug": "c",
+        "institution": "",
+        "link": "",
+        "event": 1
+    }
+},
+{
+    "model": "AKModel.akowner",
+    "pk": 4,
+    "fields": {
+        "name": "d",
+        "slug": "d",
+        "institution": "",
+        "link": "",
+        "event": 1
+    }
+},
+{
+    "model": "AKModel.akcategory",
+    "pk": 1,
+    "fields": {
+        "name": "Spaß",
+        "color": "275246",
+        "description": "",
+        "present_by_default": true,
+        "event": 1
+    }
+},
+{
+    "model": "AKModel.akcategory",
+    "pk": 2,
+    "fields": {
+        "name": "Ernst",
+        "color": "234567",
+        "description": "",
+        "present_by_default": true,
+        "event": 1
+    }
+},
+{
+    "model": "AKModel.akcategory",
+    "pk": 3,
+    "fields": {
+        "name": "Spaß/Kultur",
+        "color": "333333",
+        "description": "",
+        "present_by_default": true,
+        "event": 2
+    }
+},
+{
+    "model": "AKModel.akcategory",
+    "pk": 4,
+    "fields": {
+        "name": "Inhalt",
+        "color": "456789",
+        "description": "",
+        "present_by_default": true,
+        "event": 2
+    }
+},
+{
+    "model": "AKModel.akcategory",
+    "pk": 5,
+    "fields": {
+        "name": "Meta",
+        "color": "111111",
+        "description": "",
+        "present_by_default": true,
+        "event": 2
+    }
+},
+{
+    "model": "AKModel.aktrack",
+    "pk": 1,
+    "fields": {
+        "name": "Track 1",
+        "color": "",
+        "event": 2
+    }
+},
+{
+    "model": "AKModel.akrequirement",
+    "pk": 1,
+    "fields": {
+        "name": "Beamer",
+        "event": 1
+    }
+},
+{
+    "model": "AKModel.akrequirement",
+    "pk": 2,
+    "fields": {
+        "name": "Internet",
+        "event": 1
+    }
+},
+{
+    "model": "AKModel.akrequirement",
+    "pk": 3,
+    "fields": {
+        "name": "BBB",
+        "event": 2
+    }
+},
+{
+    "model": "AKModel.akrequirement",
+    "pk": 4,
+    "fields": {
+        "name": "Mumble",
+        "event": 2
+    }
+},
+{
+    "model": "AKModel.akrequirement",
+    "pk": 5,
+    "fields": {
+        "name": "Matrix",
+        "event": 2
+    }
+},
+{
+    "model": "AKModel.aktype",
+    "pk": 1,
+    "fields": {
+        "name": "Input",
+        "event": 2
+    }
+},
+{
+    "model": "AKModel.historicalak",
+    "pk": 1,
+    "fields": {
+        "id": 1,
+        "name": "Test AK Inhalt",
+        "short_name": "test1",
+        "description": "",
+        "link": "",
+        "protocol_link": "",
+        "reso": false,
+        "present": true,
+        "notes": "",
+        "category": 4,
+        "track": null,
+        "event": 2,
+        "history_date": "2021-05-04T10:28:59.265Z",
+        "history_change_reason": null,
+        "history_type": "+",
+        "history_user": null
+    }
+},
+{
+    "model": "AKModel.historicalak",
+    "pk": 2,
+    "fields": {
+        "id": 1,
+        "name": "Test AK Inhalt",
+        "short_name": "test1",
+        "description": "",
+        "link": "",
+        "protocol_link": "",
+        "reso": false,
+        "present": true,
+        "notes": "",
+        "category": 4,
+        "track": null,
+        "event": 2,
+        "history_date": "2021-05-04T10:28:59.305Z",
+        "history_change_reason": null,
+        "history_type": "~",
+        "history_user": null
+    }
+},
+{
+    "model": "AKModel.historicalak",
+    "pk": 3,
+    "fields": {
+        "id": 2,
+        "name": "Test AK Meta",
+        "short_name": "test2",
+        "description": "",
+        "link": "",
+        "protocol_link": "",
+        "reso": false,
+        "present": null,
+        "notes": "",
+        "category": 5,
+        "track": null,
+        "event": 2,
+        "history_date": "2021-05-04T10:29:40.296Z",
+        "history_change_reason": null,
+        "history_type": "+",
+        "history_user": null
+    }
+},
+{
+    "model": "AKModel.historicalak",
+    "pk": 4,
+    "fields": {
+        "id": 2,
+        "name": "Test AK Meta",
+        "short_name": "test2",
+        "description": "",
+        "link": "",
+        "protocol_link": "",
+        "reso": false,
+        "present": null,
+        "notes": "",
+        "category": 5,
+        "track": null,
+        "event": 2,
+        "history_date": "2021-05-04T10:29:40.355Z",
+        "history_change_reason": null,
+        "history_type": "~",
+        "history_user": null
+    }
+},
+{
+    "model": "AKModel.historicalak",
+    "pk": 5,
+    "fields": {
+        "id": 3,
+        "name": "AK Wish",
+        "short_name": "wish1",
+        "description": "Description of my Wish",
+        "link": "",
+        "protocol_link": "",
+        "reso": false,
+        "present": null,
+        "notes": "We need to find a volunteer first...",
+        "category": 3,
+        "track": null,
+        "event": 2,
+        "history_date": "2021-05-04T10:30:59.469Z",
+        "history_change_reason": null,
+        "history_type": "+",
+        "history_user": null
+    }
+},
+{
+    "model": "AKModel.historicalak",
+    "pk": 6,
+    "fields": {
+        "id": 3,
+        "name": "AK Wish",
+        "short_name": "wish1",
+        "description": "Description of my Wish",
+        "link": "",
+        "protocol_link": "",
+        "reso": false,
+        "present": null,
+        "notes": "We need to find a volunteer first...",
+        "category": 3,
+        "track": null,
+        "event": 2,
+        "history_date": "2021-05-04T10:30:59.509Z",
+        "history_change_reason": null,
+        "history_type": "~",
+        "history_user": null
+    }
+},
+{
+    "model": "AKModel.historicalak",
+    "pk": 7,
+    "fields": {
+        "id": 2,
+        "name": "Test AK Meta",
+        "short_name": "test2",
+        "description": "",
+        "link": "",
+        "protocol_link": "",
+        "reso": false,
+        "present": null,
+        "notes": "",
+        "category": 5,
+        "track": 1,
+        "event": 2,
+        "history_date": "2022-12-02T12:27:14.277Z",
+        "history_change_reason": null,
+        "history_type": "~",
+        "history_user": null
+    }
+},
+{
+    "model": "AKModel.ak",
+    "pk": 1,
+    "fields": {
+        "name": "Test AK Inhalt",
+        "short_name": "test1",
+        "description": "",
+        "link": "",
+        "protocol_link": "",
+        "category": 4,
+        "track": null,
+        "reso": false,
+        "present": true,
+        "notes": "",
+        "interest": -1,
+        "interest_counter": 0,
+        "include_in_export": false,
+        "event": 2,
+        "owners": [
+            1
+        ],
+        "requirements": [
+            3
+        ],
+        "conflicts": [],
+        "prerequisites": []
+    }
+},
+{
+    "model": "AKModel.ak",
+    "pk": 2,
+    "fields": {
+        "name": "Test AK Meta",
+        "short_name": "test2",
+        "description": "",
+        "link": "",
+        "protocol_link": "",
+        "category": 5,
+        "track": 1,
+        "reso": false,
+        "present": null,
+        "notes": "",
+        "interest": -1,
+        "interest_counter": 0,
+        "event": 2,
+        "owners": [
+            2
+        ],
+        "requirements": [],
+        "conflicts": [],
+        "prerequisites": []
+    }
+},
+{
+    "model": "AKModel.ak",
+    "pk": 3,
+    "fields": {
+        "name": "AK Wish",
+        "short_name": "wish1",
+        "description": "Description of my Wish",
+        "link": "",
+        "protocol_link": "",
+        "category": 3,
+        "track": null,
+        "reso": false,
+        "present": null,
+        "notes": "We need to find a volunteer first...",
+        "interest": -1,
+        "interest_counter": 0,
+        "event": 2,
+        "owners": [],
+        "requirements": [
+            4
+        ],
+        "conflicts": [
+            1
+        ],
+        "prerequisites": [
+            2
+        ]
+    }
+},
+{
+    "model": "AKModel.ak",
+    "pk": 4,
+    "fields": {
+        "name": "Test AK fixed slots",
+        "short_name": "testfixed",
+        "description": "",
+        "link": "",
+        "protocol_link": "",
+        "category": 4,
+        "track": null,
+        "reso": false,
+        "present": true,
+        "notes": "",
+        "interest": -1,
+        "interest_counter": 0,
+        "include_in_export": false,
+        "event": 2,
+        "owners": [
+            1
+        ],
+        "requirements": [
+            3
+        ],
+        "conflicts": [],
+        "prerequisites": []
+    }
+},
+{
+    "model": "AKModel.ak",
+    "pk": 5,
+    "fields": {
+        "name": "Test AK Ernst",
+        "short_name": "testernst",
+        "description": "",
+        "link": "",
+        "protocol_link": "",
+        "category": 2,
+        "track": null,
+        "reso": false,
+        "present": true,
+        "notes": "",
+        "interest": -1,
+        "interest_counter": 0,
+        "include_in_export": false,
+        "event": 1,
+        "owners": [
+            3
+        ],
+        "requirements": [
+            2
+        ],
+        "conflicts": [],
+        "prerequisites": []
+    }
+},
+{
+    "model": "AKModel.room",
+    "pk": 1,
+    "fields": {
+        "name": "Testraum",
+        "location": "BBB",
+        "capacity": -1,
+        "event": 2,
+        "properties": [
+            3
+        ]
+    }
+},
+{
+    "model": "AKModel.room",
+    "pk": 2,
+    "fields": {
+        "name": "Testraum 2",
+        "location": "",
+        "capacity": 30,
+        "event": 2,
+        "properties": []
+    }
+},
+{
+    "model": "AKModel.room",
+    "pk": 3,
+    "fields": {
+        "name": "BBB Session 1",
+        "location": "",
+        "capacity": -1,
+        "event": 1,
+        "properties": [
+            2
+        ]
+    }
+},
+{
+    "model": "AKModel.akslot",
+    "pk": 1,
+    "fields": {
+        "ak": 1,
+        "room": 2,
+        "start": "2020-11-06T18:30:00Z",
+        "duration": "2.00",
+        "fixed": false,
+        "event": 2,
+        "updated": "2022-12-02T12:23:11.856Z"
+    }
+},
+{
+    "model": "AKModel.akslot",
+    "pk": 2,
+    "fields": {
+        "ak": 2,
+        "room": 1,
+        "start": "2020-11-08T12:30:00Z",
+        "duration": "2.00",
+        "fixed": false,
+        "event": 2,
+        "updated": "2022-12-02T12:23:18.279Z"
+    }
+},
+{
+    "model": "AKModel.akslot",
+    "pk": 3,
+    "fields": {
+        "ak": 3,
+        "room": null,
+        "start": null,
+        "duration": "1.50",
+        "fixed": false,
+        "event": 2,
+        "updated": "2021-05-04T10:30:59.523Z"
+    }
+},
+{
+    "model": "AKModel.akslot",
+    "pk": 4,
+    "fields": {
+        "ak": 3,
+        "room": null,
+        "start": null,
+        "duration": "3.00",
+        "fixed": false,
+        "event": 2,
+        "updated": "2021-05-04T10:30:59.528Z"
+    }
+},
+{
+    "model": "AKModel.akslot",
+    "pk": 5,
+    "fields": {
+        "ak": 1,
+        "room": null,
+        "start": null,
+        "duration": "2.00",
+        "fixed": false,
+        "event": 2,
+        "updated": "2022-12-02T12:23:11.856Z"
+    }
+},
+{
+    "model": "AKModel.akslot",
+    "pk": 6,
+    "fields": {
+        "ak": 4,
+        "room": null,
+        "start": "2020-11-08T18:30:00Z",
+        "duration": "2.00",
+        "fixed": true,
+        "event": 2,
+        "updated": "2022-12-02T12:23:11.856Z"
+    }
+},
+{
+    "model": "AKModel.akslot",
+    "pk": 7,
+    "fields": {
+        "ak": 4,
+        "room": 2,
+        "start": null,
+        "duration": "2.00",
+        "fixed": true,
+        "event": 2,
+        "updated": "2022-12-02T12:23:11.856Z"
+    }
+},
+{
+    "model": "AKModel.akslot",
+    "pk": 8,
+    "fields": {
+        "ak": 4,
+        "room": 2,
+        "start": "2020-11-07T16:00:00Z",
+        "duration": "2.00",
+        "fixed": true,
+        "event": 2,
+        "updated": "2022-12-02T12:23:11.856Z"
+    }
+},
+{
+    "model": "AKModel.akslot",
+    "pk": 9,
+    "fields": {
+        "ak": 5,
+        "room": null,
+        "start": null,
+        "duration": "2.00",
+        "fixed": false,
+        "event": 1,
+        "updated": "2022-12-02T12:23:11.856Z"
+    }
+},
+{
+    "model": "AKModel.constraintviolation",
+    "pk": 1,
+    "fields": {
+        "type": "soa",
+        "level": 10,
+        "event": 2,
+        "ak_owner": null,
+        "room": null,
+        "requirement": null,
+        "category": null,
+        "comment": "",
+        "timestamp": "2022-12-02T12:23:11.875Z",
+        "manually_resolved": false,
+        "aks": [
+            1
+        ],
+        "ak_slots": [
+            1
+        ]
+    }
+},
+{
+    "model": "AKModel.constraintviolation",
+    "pk": 2,
+    "fields": {
+        "type": "rng",
+        "level": 10,
+        "event": 2,
+        "ak_owner": null,
+        "room": 2,
+        "requirement": 3,
+        "category": null,
+        "comment": "",
+        "timestamp": "2022-12-02T12:23:11.890Z",
+        "manually_resolved": false,
+        "aks": [
+            1
+        ],
+        "ak_slots": [
+            1
+        ]
+    }
+},
+{
+    "model": "AKModel.constraintviolation",
+    "pk": 3,
+    "fields": {
+        "type": "soa",
+        "level": 10,
+        "event": 2,
+        "ak_owner": null,
+        "room": null,
+        "requirement": null,
+        "category": null,
+        "comment": "",
+        "timestamp": "2022-12-02T12:23:18.301Z",
+        "manually_resolved": false,
+        "aks": [
+            2
+        ],
+        "ak_slots": [
+            2
+        ]
+    }
+},
+{
+    "model": "AKModel.availability",
+    "pk": 1,
+    "fields": {
+        "event": 2,
+        "person": null,
+        "room": null,
+        "ak": 1,
+        "ak_category": null,
+        "start": "2020-11-07T08:00:00Z",
+        "end": "2020-11-07T18:00:00Z"
+    }
+},
+{
+    "model": "AKModel.availability",
+    "pk": 2,
+    "fields": {
+        "event": 2,
+        "person": null,
+        "room": null,
+        "ak": 1,
+        "ak_category": null,
+        "start": "2020-11-09T10:00:00Z",
+        "end": "2020-11-09T16:30:00Z"
+    }
+},
+{
+    "model": "AKModel.availability",
+    "pk": 3,
+    "fields": {
+        "event": 2,
+        "person": null,
+        "room": 1,
+        "ak": null,
+        "ak_category": null,
+        "start": "2020-11-06T17:51:26Z",
+        "end": "2020-11-10T23:00:00Z"
+    }
+},
+{
+    "model": "AKModel.availability",
+    "pk": 4,
+    "fields": {
+        "event": 2,
+        "person": null,
+        "room": 2,
+        "ak": null,
+        "ak_category": null,
+        "start": "2020-11-06T17:51:26Z",
+        "end": "2020-11-06T21:00:00Z"
+    }
+},
+{
+    "model": "AKModel.availability",
+    "pk": 5,
+    "fields": {
+        "event": 2,
+        "person": null,
+        "room": 2,
+        "ak": null,
+        "ak_category": null,
+        "start": "2020-11-08T15:30:00Z",
+        "end": "2020-11-08T19:30:00Z"
+    }
+},
+{
+    "model": "AKModel.availability",
+    "pk": 6,
+    "fields": {
+        "event": 2,
+        "person": null,
+        "room": 2,
+        "ak": null,
+        "ak_category": null,
+        "start": "2020-11-07T18:30:00Z",
+        "end": "2020-11-07T21:30:00Z"
+    }
+},
+{
+    "model": "AKModel.availability",
+    "pk": 7,
+    "fields": {
+        "event": 1,
+        "person": null,
+        "room": null,
+        "ak": 5,
+        "ak_category": null,
+        "start": "2020-10-01T17:41:22Z",
+        "end": "2020-10-04T17:41:30Z"
+    }
+},
+{
+    "model": "AKModel.availability",
+    "pk": 8,
+    "fields": {
+        "event": 1,
+        "person": null,
+        "room": 3,
+        "ak": null,
+        "ak_category": null,
+        "start": "2020-10-01T17:41:22Z",
+        "end": "2020-10-04T17:41:30Z"
+    }
+},
+{
+    "model": "AKModel.defaultslot",
+    "pk": 1,
+    "fields": {
+        "event": 2,
+        "start": "2020-11-07T08:00:00Z",
+        "end": "2020-11-07T12:00:00Z",
+        "primary_categories": [5]
+    }
+},
+{
+    "model": "AKModel.defaultslot",
+    "pk": 2,
+    "fields": {
+        "event": 2,
+        "start": "2020-11-07T14:00:00Z",
+        "end": "2020-11-07T17:00:00Z",
+        "primary_categories": [4]
+    }
+},
+{
+    "model": "AKModel.defaultslot",
+    "pk": 3,
+    "fields": {
+        "event": 2,
+        "start": "2020-11-08T08:00:00Z",
+        "end": "2020-11-08T19:00:00Z",
+        "primary_categories": [4, 5]
+    }
+},
+{
+    "model": "AKModel.defaultslot",
+    "pk": 4,
+    "fields": {
+        "event": 2,
+        "start": "2020-11-09T17:00:00Z",
+        "end": "2020-11-10T01:00:00Z",
+        "primary_categories": [4, 5, 3]
+    }
+}
+]

AKModel/forms.py

+"""
+Central and admin forms
+"""
+
+import csv
+import io
+import json
+
+from django import forms
+from django.core.exceptions import ValidationError
+from django.forms.utils import ErrorList
+from django.utils.translation import gettext_lazy as _
+from jsonschema.exceptions import best_match
+
+from AKModel.availability.forms import AvailabilitiesFormMixin
+from AKModel.models import Event, AKCategory, AKRequirement, Room, AKType
+from AKModel.utils import construct_schema_validator
+
+
+class DateTimeInput(forms.DateInput):
+    """
+    Simple widget for datetime input fields using the HTML5 datetime-local input type
+    """
+    input_type = 'datetime-local'
+
+
+class NewEventWizardStartForm(forms.ModelForm):
+    """
+    Initial view of new event wizard
+
+    This form is a model form for Event, but only with a subset of the required fields.
+    It is therefore not possible to really create an event using this form, but only to enter
+    information, in particular the timezone, that is needed to correctly handle/parse the user
+    inputs for further required fields like start and end of the event.
+
+    The form will be used for this partial input, the input of the remaining required fields
+    will then be handled by :class:`NewEventWizardSettingsForm` (see below).
+    """
+    class Meta:
+        model = Event
+        fields = ['name', 'slug', 'timezone', 'plan_hidden']
+        widgets = {
+            'plan_hidden': forms.HiddenInput(),
+        }
+
+    # Special hidden field for wizard state handling
+    is_init = forms.BooleanField(initial=True, widget=forms.HiddenInput)
+
+
+class NewEventWizardSettingsForm(forms.ModelForm):
+    """
+    Form for second view of the event creation wizard.
+
+    Will handle the input of the remaining required as well as some optional fields.
+    See also :class:`NewEventWizardStartForm`.
+    """
+    class Meta:
+        model = Event
+        fields = "__all__"
+        exclude = ['plan_published_at']
+        widgets = {
+            'name': forms.HiddenInput(),
+            'slug': forms.HiddenInput(),
+            'timezone': forms.HiddenInput(),
+            'active': forms.HiddenInput(),
+            'start': DateTimeInput(),
+            'end': DateTimeInput(),
+            'interest_start': DateTimeInput(),
+            'interest_end': DateTimeInput(),
+            'reso_deadline': DateTimeInput(),
+            'plan_hidden': forms.HiddenInput(),
+        }
+
+
+class NewEventWizardPrepareImportForm(forms.Form):
+    """
+    Wizard form for choosing an event to import/copy elements (requirements, categories, etc) from.
+    Is used to restrict the list of elements to choose from in the next step (see :class:`NewEventWizardImportForm`).
+    """
+    import_event = forms.ModelChoiceField(
+        queryset=Event.objects.all(),
+        label=_("Copy ak requirements and ak categories of existing event"),
+        help_text=_("You can choose what to copy in the next step")
+    )
+
+
+class NewEventWizardImportForm(forms.Form):
+    """
+    Wizard form for excaclty choosing which elemments to copy/import for the newly created event.
+    Possible elements are categories, requirements, and dashboard buttons if AKDashboard is active.
+    The lists are restricted to elements from the event selected in the previous step
+    (see :class:`NewEventWizardPrepareImportForm`).
+    """
+    import_categories = forms.ModelMultipleChoiceField(
+        queryset=AKCategory.objects.all(),
+        widget=forms.CheckboxSelectMultiple,
+        label=_("Copy ak categories"),
+        required=False,
+    )
+
+    import_requirements = forms.ModelMultipleChoiceField(
+        queryset=AKRequirement.objects.all(),
+        widget=forms.CheckboxSelectMultiple,
+        label=_("Copy ak requirements"),
+        required=False,
+    )
+
+    import_types = forms.ModelMultipleChoiceField(
+        queryset=AKType.objects.all(),
+        widget=forms.CheckboxSelectMultiple,
+        label=_("Copy types"),
+        required=False,
+    )
+
+    # pylint: disable=too-many-arguments
+    def __init__(self, data=None, files=None, auto_id='id_%s', prefix=None, initial=None, error_class=ErrorList,
+                 label_suffix=None, empty_permitted=False, field_order=None, use_required_attribute=None,
+                 renderer=None):
+        super().__init__(data, files, auto_id, prefix, initial, error_class, label_suffix, empty_permitted, field_order,
+                         use_required_attribute, renderer)
+        self.fields["import_categories"].queryset = self.fields["import_categories"].queryset.filter(
+            event=self.initial["import_event"])
+        self.fields["import_requirements"].queryset = self.fields["import_requirements"].queryset.filter(
+            event=self.initial["import_event"])
+        self.fields["import_types"].queryset = self.fields["import_types"].queryset.filter(
+            event=self.initial["import_event"])
+
+        # pylint: disable=import-outside-toplevel
+        # Local imports used to prevent cyclic imports and to only import when AKDashboard is available
+        from django.apps import apps
+        if apps.is_installed("AKDashboard"):
+            # If AKDashboard is active, allow to copy dashboard buttons, too
+            from AKDashboard.models import DashboardButton
+            self.fields["import_buttons"] = forms.ModelMultipleChoiceField(
+                queryset=DashboardButton.objects.filter(event=self.initial["import_event"]),
+                widget=forms.CheckboxSelectMultiple,
+                label=_("Copy dashboard buttons"),
+                required=False,
+            )
+
+
+class NewEventWizardActivateForm(forms.ModelForm):
+    """
+    Wizard form to activate the newly created event
+    """
+    class Meta:
+        fields = ["active"]
+        model = Event
+
+
+class AdminIntermediateForm(forms.Form):
+    """
+    Base form for admin intermediate views (forms used there should inherit from this,
+    by default, the form is empty since it is only needed for the confirmation button)
+    """
+
+
+class AdminIntermediateActionForm(AdminIntermediateForm):
+    """
+    Form for Admin Action Confirmation views -- has a pks field needed to handle the serialization/deserialization of
+    the IDs of the entities the user selected for the admin action to be performed on
+    """
+    pks = forms.CharField(widget=forms.HiddenInput)
+
+
+class SlideExportForm(AdminIntermediateForm):
+    """
+    Form to control the slides generated from the AK list of an event
+
+    The user can select how many upcoming AKs are displayed at the footer to inform people that it is their turn soon,
+    whether the AK list should be restricted to those AKs that where marked for presentation, and whether ther should
+    be a symbol and empty space to take notes on for wishes
+    """
+    num_next = forms.IntegerField(
+        min_value=0,
+        max_value=6,
+        initial=3,
+        label=_("# next AKs"),
+        help_text=_("How many next AKs should be shown on a slide?"))
+    presentation_mode = forms.TypedChoiceField(
+        initial=False,
+        label=_("Presentation only?"),
+        widget=forms.RadioSelect,
+        choices=((True, _('Yes')), (False, _('No'))),
+        coerce=lambda x: x == "True",
+        help_text=_("Restrict AKs to those that asked for chance to be presented?"))
+    wish_notes = forms.TypedChoiceField(
+        initial=False,
+        label=_("Space for notes in wishes?"),
+        widget=forms.RadioSelect,
+        choices=((True, _('Yes')), (False, _('No'))),
+        coerce=lambda x: x == "True",
+        help_text=_("Create symbols indicating space to note down owners and timeslots for wishes, e.g., to be filled "
+                    "out on a touch screen while presenting?"))
+
+
+class DefaultSlotEditorForm(AdminIntermediateForm):
+    """
+    Form for default slot editor
+    """
+    availabilities = forms.CharField(
+        label=_('Default Slots'),
+        help_text=_(
+            'Click and drag to add default slots, double-click to delete. '
+            'Or use the start and end inputs to add entries to the calendar view.'
+        ),
+        widget=forms.TextInput(attrs={'class': 'availabilities-editor-data'}),
+        required=True,
+    )
+
+
+class RoomBatchCreationForm(AdminIntermediateForm):
+    """
+    Form for room batch creation
+
+    Allows to input a list of room details and choose whether default availabilities should be generated for these
+    rooms. Will check that the input follows a CSV format with at least a name column present.
+    """
+    rooms = forms.CharField(
+        label=_('New rooms'),
+        help_text=_('Enter room details in CSV format. Required colum is "name", optional colums are "location", '
+                    '"capacity", and "url" for online/hybrid rooms. Delimiter: Semicolon'),
+        widget=forms.Textarea,
+        required=True,
+    )
+    create_default_availabilities = forms.BooleanField(
+        label=_('Default availabilities?'),
+        help_text=_('Create default availabilities for all rooms?'),
+        required=False
+    )
+
+    def clean_rooms(self):
+        """
+        Validate and transform the input for the rooms textfield
+        Treat the input as CSV and turn it into a dict containing the relevant information.
+
+        :return: a dict containing the raw room information
+        :rtype: dict[str, str]
+        """
+        rooms_raw_text = self.cleaned_data["rooms"]
+        rooms_raw_dict = csv.DictReader(io.StringIO(rooms_raw_text), delimiter=";")
+
+        if "name" not in rooms_raw_dict.fieldnames:
+            raise forms.ValidationError(_("CSV must contain a name column"))
+
+        return rooms_raw_dict
+
+
+class RoomForm(forms.ModelForm):
+    """
+    Room (creation) form (basic), will be extended for handling of availabilities
+    (see :class:`RoomFormWithAvailabilities`) and also for creating hybrid rooms in AKOnline (if active)
+    """
+    class Meta:
+        model = Room
+        fields = ['name',
+                  'location',
+                  'capacity',
+                  'event',
+                  ]
+
+
+class RoomFormWithAvailabilities(AvailabilitiesFormMixin, RoomForm):
+    """
+    Room (update) form including handling of availabilities, extends :class:`RoomForm`
+    """
+    class Meta:
+        model = Room
+        fields = ['name',
+                  'location',
+                  'capacity',
+                  'properties',
+                  'event',
+                  ]
+
+        widgets = {
+            'properties': forms.CheckboxSelectMultiple,
+        }
+
+    def __init__(self, *args, **kwargs):
+        # Init availability mixin
+        kwargs['initial'] = {}
+        super().__init__(*args, **kwargs)
+        self.initial = {**self.initial, **kwargs['initial']}
+        # Filter possible values for m2m when event is specified
+        if hasattr(self.instance, "event") and self.instance.event is not None:
+            self.fields["properties"].queryset = AKRequirement.objects.filter(event=self.instance.event)
+
+
+class JSONScheduleImportForm(AdminIntermediateForm):
+    """Form to import an AK schedule from a json file."""
+    json_data = forms.CharField(
+        required=False,
+        widget=forms.Textarea,
+        label=_("JSON data"),
+        help_text=_("JSON data from the scheduling solver"),
+    )
+
+    json_file = forms.FileField(
+        required=False,
+        label=_("File with JSON data"),
+        help_text=_("File with JSON data from the scheduling solver"),
+    )
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.json_schema_validator = construct_schema_validator(
+            schema="solver-output.schema.json"
+        )
+
+    def _check_json_data(self, data: str):
+        """Validate `data` against our JSON schema.
+
+        :param data: The JSON string to validate using `self.json_schema_validator`.
+        :type data: str
+        :raises ValidationError: if the validation fails, with a description of the cause.
+        :return: The parsed JSON dict, if validation is successful.
+        """
+        try:
+            schedule = json.loads(data)
+        except json.JSONDecodeError as ex:
+            raise ValidationError(_("Cannot decode as JSON"), "invalid") from ex
+
+        error = best_match(self.json_schema_validator.iter_errors(schedule))
+        if error:
+            raise ValidationError(
+                _("Invalid JSON format: %(msg)s at %(error_path)s"),
+                "invalid",
+                params={
+                    "msg": error.message,
+                    "error_path": error.json_path
+                }
+            ) from error
+
+        return schedule
+
+    def clean(self):
+        """Extract and validate entered JSON data.
+
+        We allow entering of the schedule from two sources:
+        1. from an uploaded file
+        2. from a text field.
+
+        This function checks that data is entered from exactly one source.
+        If so, the entered JSON string is validated against our schema.
+        Any errors are reported at the corresponding form field.
+        """
+        cleaned_data = super().clean()
+        if cleaned_data.get("json_file") and cleaned_data.get("json_data"):
+            err = ValidationError(
+                _("Please enter data as a file OR via text, not both."), "invalid"
+            )
+            self.add_error("json_data", err)
+            self.add_error("json_file", err)
+        elif not (cleaned_data.get("json_file") or cleaned_data.get("json_data")):
+            err = ValidationError(
+                _("No data entered. Please enter data as a file or via text."), "invalid"
+            )
+            self.add_error("json_data", err)
+            self.add_error("json_file", err)
+        else:
+            source_field = "json_data"
+            data = cleaned_data.get(source_field)
+            if not data:
+                source_field = "json_file"
+                with cleaned_data.get(source_field).open() as ff:
+                    data = ff.read()
+            try:
+                cleaned_data["data"] = self._check_json_data(data)
+            except ValidationError as ex:
+                self.add_error(source_field, ex)
+        return cleaned_data

AKModel/metaviews/__init__.py

+from AKModel.metaviews.status import StatusManager
+
+# create on instance of the :class:`AKModel.metaviews.status.StatusManager`
+# that can then be accessed everywhere (singleton pattern)
+status_manager = StatusManager()