Move core exporters to their own package

src/pretix/base/exporters/mail.py

@@ -0,0 +1,40 @@
+from collections import OrderedDict
+
+from django import forms
+from django.dispatch import receiver
+from django.utils.translation import ugettext as _
+
+from ..exporter import BaseExporter
+from ..models import Order
+from ..signals import register_data_exporters
+
+
+class MailExporter(BaseExporter):
+    identifier = 'mailaddrs'
+    verbose_name = _('Email addresses (text file)')
+
+    def render(self, form_data: dict):
+        qs = self.event.orders.filter(status__in=form_data['status'])
+        addrs = qs.values('email')
+        data = "\r\n".join(set(a['email'] for a in addrs))
+        return 'pretixemails.txt', 'text/plain', data.encode("utf-8")
+
+    @property
+    def export_form_fields(self):
+        return OrderedDict(
+            [
+                ('status',
+                 forms.MultipleChoiceField(
+                     label=_('Filter by status'),
+                     initial=[Order.STATUS_PENDING, Order.STATUS_PAID],
+                     choices=Order.STATUS_CHOICE,
+                     widget=forms.CheckboxSelectMultiple,
+                     required=False
+                 )),
+            ]
+        )
+
+
+@receiver(register_data_exporters, dispatch_uid="exporter_mail")
+def register_mail_export(sender, **kwargs):
+    return MailExporter