Configurable invoice prefixes

src/pretix/base/migrations/0069_invoice_prefix.py

@@ -0,0 +1,47 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.2 on 2017-07-17 19:29
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+from django.db.models import deletion
+
+
+def fwd(app, schema_editor):
+    Event = app.get_model('pretixbase', 'Event')
+    for e in Event.objects.select_related('organizer').all():
+        e.invoices.all().update(prefix=e.slug.upper() + '-', organizer=e.organizer)
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('pretixbase', '0068_subevent_frontpage_text'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='invoice',
+            name='prefix',
+            field=models.CharField(db_index=True, default='', max_length=160),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='invoice',
+            name='organizer',
+            field=models.ForeignKey(null=True,
+                                    on_delete=deletion.PROTECT,
+                                    related_name='invoices', to='pretixbase.Organizer'),
+            preserve_default=False,
+        ),
+        migrations.RunPython(
+            fwd, migrations.RunPython.noop
+        ),
+        migrations.AlterUniqueTogether(
+            name='invoice',
+            unique_together=set([('organizer', 'prefix', 'invoice_no')]),
+        ),
+        migrations.AlterField(
+            model_name='invoice',
+            name='organizer',
+            field=models.ForeignKey(on_delete=deletion.PROTECT, related_name='invoices', to='pretixbase.Organizer'),
+        ),
+    ]

src/pretix/base/models/invoices.py

@@ -29,6 +29,8 @@ class Invoice(models.Model):
     :type order: Order
     :param event: The event this belongs to (for convenience)
     :type event: Event
+    :param organizer: The organizer this belongs to (redundant, for enforcing uniqueness)
+    :type organizer: Organizer
     :param invoice_no: The human-readable, event-unique invoice number
     :type invoice_no: int
     :param is_cancellation: Whether or not this is a cancellation instead of an invoice
@@ -55,7 +57,9 @@ class Invoice(models.Model):
     :type file: File
     """
     order = models.ForeignKey('Order', related_name='invoices', db_index=True)
+    organizer = models.ForeignKey('Organizer', related_name='invoices', db_index=True, on_delete=models.PROTECT)
     event = models.ForeignKey('Event', related_name='invoices', db_index=True)
+    prefix = models.CharField(max_length=160, db_index=True)
     invoice_no = models.CharField(max_length=19, db_index=True)
     is_cancellation = models.BooleanField(default=False)
     refers = models.ForeignKey('Invoice', related_name='refered', null=True, blank=True)
@@ -74,7 +78,10 @@ class Invoice(models.Model):
         return '{:05d}'.format(int(number))
 
     def _get_numeric_invoice_number(self):
-        numeric_invoices = Invoice.objects.filter(event=self.event).exclude(invoice_no__contains='-')
+        numeric_invoices = Invoice.objects.filter(
+            event__organizer=self.event.organizer,
+            prefix=self.prefix,
+        ).exclude(invoice_no__contains='-')
         return self._to_numeric_invoice_number(numeric_invoices.count() + 1)
 
     def _get_invoice_number_from_order(self):
@@ -88,6 +95,10 @@ class Invoice(models.Model):
             raise ValueError('Every invoice needs to be connected to an order')
         if not self.event:
             self.event = self.order.event
+        if not self.organizer:
+            self.organizer = self.order.event.organizer
+        if not self.prefix:
+            self.prefix = self.event.settings.invoice_numbers_prefix or (self.event.slug.upper() + '-')
         if not self.invoice_no:
             for i in range(10):
                 if self.event.settings.get('invoice_numbers_consecutive'):
@@ -116,8 +127,8 @@ class Invoice(models.Model):
         """
         Returns the invoice number in a human-readable string with the event slug prepended.
         """
-        return '{event}-{code}'.format(
-            event=self.event.slug.upper(),
+        return '{prefix}{code}'.format(
+            prefix=self.prefix,
             code=self.invoice_no
         )
 
@@ -126,7 +137,7 @@ class Invoice(models.Model):
         return self.refered.filter(is_cancellation=True).exists()
 
     class Meta:
-        unique_together = ('event', 'invoice_no')
+        unique_together = ('organizer', 'prefix', 'invoice_no')
         ordering = ('invoice_no',)
 
 

src/pretix/base/services/invoices.py

@@ -96,6 +96,7 @@ def generate_cancellation(invoice: Invoice):
     cancellation = copy.copy(invoice)
     cancellation.pk = None
     cancellation.invoice_no = None
+    cancellation.prefix = None
     cancellation.refers = invoice
     cancellation.is_cancellation = True
     cancellation.date = timezone.now().date()
@@ -125,6 +126,7 @@ def generate_invoice(order: Order):
     invoice = Invoice(
         order=order,
         event=order.event,
+        organizer=order.event.organizer,
         date=timezone.now().date(),
         locale=locale
     )
@@ -171,7 +173,7 @@ def build_preview_invoice_pdf(event):
                                     expires=timezone.now(), code="PREVIEW", total=119)
         invoice = Invoice(
             order=order, event=event, invoice_no="PREVIEW",
-            date=timezone.now().date(), locale=locale
+            date=timezone.now().date(), locale=locale, organizer=event.organizer
         )
         invoice.invoice_from = event.settings.get('invoice_address_from')
 

src/pretix/base/settings.py

@@ -61,6 +61,10 @@ DEFAULTS = {
         'default': 'True',
         'type': bool,
     },
+    'invoice_numbers_prefix': {
+        'default': '',
+        'type': str,
+    },
     'invoice_renderer': {
         'default': 'classic',
         'type': str,