Orders API: Allow to filter by subevent

doc/api/resources/orders.rst

@@ -132,6 +132,10 @@ last_modified                         datetime                   Last modificati
 
    The ``item`` and ``variation`` query parameters have been added.
 
+.. versionchanged:: 4.6
+
+   The ``subevent`` query parameters has been added.
+
 
 .. _order-position-resource:
 
@@ -433,6 +437,7 @@ List of all orders
        recommend using this in combination with ``testmode=false``, since test mode orders can vanish at any time and
        you will not notice it using this method.
    :query datetime created_since: Only return orders that have been created since the given date.
+   :query integer subevent: Only return orders with a position that contains this subevent ID. *Warning:* Result will also include orders if they contain mixed subevents, and it will even return orders where the subevent is only contained in a canceled position.
    :query datetime subevent_after: Only return orders that contain a ticket for a subevent taking place after the given date. This is an exclusive after, and it considers the **end** of the subevent (or its start, if the end is not set).
    :query datetime subevent_before: Only return orders that contain a ticket for a subevent taking place after the given date. This is an exclusive before, and it considers the **start** of the subevent.
    :query string exclude: Exclude a field from the output, e.g. ``fees`` or ``positions.downloads``. Can be used as a performance optimization. Can be passed multiple times.

src/pretix/api/views/order.py

@@ -94,6 +94,7 @@ with scopes_disabled():
         search = django_filters.CharFilter(method='search_qs')
         item = django_filters.CharFilter(field_name='all_positions', lookup_expr='item_id')
         variation = django_filters.CharFilter(field_name='all_positions', lookup_expr='variation_id')
+        subevent = django_filters.CharFilter(field_name='all_positions', lookup_expr='subevent_id')
 
         class Meta:
             model = Order