Refs #654 -- REST API: Allow invoice creation

doc/api/resources/orders.rst

@@ -953,7 +953,7 @@ Order state operations
 
 .. http:post:: /api/v1/organizers/(organizer)/events/(event)/orders/(code)/mark_expired/
 
-   Marks a unpaid order as expired.
+   Marks an unpaid order as expired.
 
    **Example request**:
 
@@ -1115,6 +1115,47 @@ Order state operations
    :statuscode 403: The requested organizer/event does not exist **or** you have no permission to view this resource.
    :statuscode 404: The requested order does not exist.
 
+Invoice generation
+------------------
+
+.. http:post:: /api/v1/organizers/(organizer)/events/(event)/orders/(code)/create_invoice/
+
+   Creates an invoice for an order which currently does not have an invoice. Returns the
+   invoice object.
+
+   **Example request**:
+
+   .. sourcecode:: http
+
+      POST /api/v1/organizers/bigevents/events/sampleconf/orders/ABC12/create_invoice/ HTTP/1.1
+      Host: pretix.eu
+      Accept: application/json, text/javascript
+
+
+   **Example response**:
+
+   .. sourcecode:: http
+
+      HTTP/1.1 200 OK
+      Vary: Accept
+      Content-Type: application/json
+
+      {
+        "order": "FOO",
+        "number": "DUMMY-00001",
+        "is_cancellation": false,
+        ...
+      }
+
+   :param organizer: The ``slug`` field of the organizer to modify
+   :param event: The ``slug`` field of the event to modify
+   :param code: The ``code`` field of the order to create an invoice for
+   :statuscode 200: no error
+   :statuscode 400: The invoice can not be created (invoicing disabled, the order already has an invoice, …)
+   :statuscode 401: Authentication failure
+   :statuscode 403: The requested organizer/event does not exist **or** you have no permission to view this resource.
+   :statuscode 404: The requested order does not exist.
+
 
 List of all order positions
 ---------------------------

src/pretix/api/views/order.py

@@ -9,6 +9,7 @@ from django.db.models.functions import Coalesce, Concat
 from django.http import FileResponse
 from django.shortcuts import get_object_or_404
 from django.utils.timezone import make_aware, now
+from django.utils.translation import ugettext as _
 from django_filters.rest_framework import DjangoFilterBackend, FilterSet
 from rest_framework import mixins, serializers, status, viewsets
 from rest_framework.decorators import detail_route
@@ -308,6 +309,38 @@ class OrderViewSet(viewsets.ModelViewSet):
         )
         return self.retrieve(request, [], **kwargs)
 
+    @detail_route(methods=['POST'])
+    def create_invoice(self, request, **kwargs):
+        order = self.get_object()
+        has_inv = order.invoices.exists() and not (
+            order.status in (Order.STATUS_PAID, Order.STATUS_PENDING)
+            and order.invoices.filter(is_cancellation=True).count() >= order.invoices.filter(is_cancellation=False).count()
+        )
+        if self.request.event.settings.get('invoice_generate') not in ('admin', 'user', 'paid', 'True') or not invoice_qualified(order):
+            return Response(
+                {'detail': _('You cannot generate an invoice for this order.')},
+                status=status.HTTP_400_BAD_REQUEST
+            )
+        elif has_inv:
+            return Response(
+                {'detail': _('An invoice for this order already exists.')},
+                status=status.HTTP_400_BAD_REQUEST
+            )
+
+        inv = generate_invoice(order)
+        order.log_action(
+            'pretix.event.order.invoice.generated',
+            user=self.request.user,
+            auth=self.request.auth,
+            data={
+                'invoice': inv.pk
+            }
+        )
+        return Response(
+            InvoiceSerializer(inv).data,
+            status=status.HTTP_201_CREATED
+        )
+
     @detail_route(methods=['POST'])
     def extend(self, request, **kwargs):
         new_date = request.data.get('expires', None)

src/tests/api/test_orders.py

@@ -2626,3 +2626,65 @@ def test_order_update_locale_to_invalid(token_client, organizer, event, order):
     )
     assert resp.status_code == 400
     assert resp.data == {'locale': ['"de" is not a supported locale for this event.']}
+
+
+@pytest.mark.django_db
+def test_order_create_invoice(token_client, organizer, event, order):
+    event.settings.invoice_generate = 'True'
+    resp = token_client.post(
+        '/api/v1/organizers/{}/events/{}/orders/{}/create_invoice/'.format(
+            organizer.slug, event.slug, order.code
+        ), format='json', data={}
+    )
+    assert resp.status_code == 201
+    assert resp.data == {
+        'order': 'FOO',
+        'number': 'DUMMY-00001',
+        'is_cancellation': False,
+        'invoice_from': '',
+        'invoice_to': 'Sample company\n\n\n \nNew Zealand',
+        'date': '2019-03-23',
+        'refers': None,
+        'locale': 'en',
+        'introductory_text': '',
+        'additional_text': '',
+        'payment_provider_text': '',
+        'footer_text': '',
+        'lines': [
+            {
+                'description': 'Budget Ticket<br />Attendee: Peter',
+                'gross_value': '23.00',
+                'tax_value': '0.00',
+                'tax_rate': '0.00',
+                'tax_name': ''
+            },
+            {
+                'description': 'Payment fee',
+                'gross_value': '0.25',
+                'tax_value': '0.05',
+                'tax_rate': '19.00',
+                'tax_name': ''
+            }
+        ],
+        'foreign_currency_display': None,
+        'foreign_currency_rate': None,
+        'foreign_currency_rate_date': None,
+        'internal_reference': ''
+    }
+
+    resp = token_client.post(
+        '/api/v1/organizers/{}/events/{}/orders/{}/create_invoice/'.format(
+            organizer.slug, event.slug, order.code
+        ), format='json', data={}
+    )
+    assert resp.data == {'detail': 'An invoice for this order already exists.'}
+    assert resp.status_code == 400
+
+    event.settings.invoice_generate = 'False'
+    resp = token_client.post(
+        '/api/v1/organizers/{}/events/{}/orders/{}/create_invoice/'.format(
+            organizer.slug, event.slug, order.code
+        ), format='json', data={}
+    )
+    assert resp.status_code == 400
+    assert resp.data == {'detail': 'You cannot generate an invoice for this order.'}