✨(backend) add order export api

As we want to export order csv, an api endpoint is needed.

src/backend/joanie/core/api/admin/__init__.py

@@ -2,11 +2,12 @@
 Admin API Endpoints
 """
 
+import csv
 from http import HTTPStatus
 
 from django.core.cache import cache
 from django.core.exceptions import ValidationError
-from django.http import JsonResponse
+from django.http import HttpResponse, JsonResponse
 
 from django_filters.rest_framework import DjangoFilterBackend
 from drf_spectacular.types import OpenApiTypes
@@ -614,6 +615,7 @@ class OrderViewSet(
     permission_classes = [permissions.IsAdminUser & permissions.DjangoModelPermissions]
     serializer_classes = {
         "list": serializers.AdminOrderLightSerializer,
+        "export": serializers.AdminOrderExportSerializer,
     }
     default_serializer_class = serializers.AdminOrderSerializer
     filterset_class = filters.OrderAdminFilterSet
@@ -689,6 +691,31 @@ def refund(self, request, pk=None):  # pylint:disable=unused-argument
 
         return Response(status=HTTPStatus.ACCEPTED)
 
+    @extend_schema(
+        request=None,
+        responses={
+            (200, "text/csv"): OpenApiTypes.OBJECT,
+            404: serializers.ErrorResponseSerializer,
+        },
+    )
+    @action(methods=["GET"], detail=False)
+    def export(self, request):
+        """
+        Export orders to a CSV file.
+        """
+        queryset = self.filter_queryset(self.get_queryset()).order_by("created_on")
+        serializer = self.get_serializer(queryset, many=True)
+        data = serializer.data
+
+        response = HttpResponse(content_type="text/csv")
+        response["Content-Disposition"] = 'attachment; filename="orders.csv"'
+        writer = csv.writer(response)
+
+        writer.writerow(data[0].keys())
+        writer.writerows([row.values() for row in data])
+
+        return response
+
 
 class OrganizationAddressViewSet(
     mixins.CreateModelMixin,

src/backend/joanie/core/serializers/admin.py

@@ -1269,6 +1269,31 @@ def get_owner_name(self, instance) -> str:
         return instance.owner.get_full_name() or instance.owner.username
 
 
+class AdminOrderExportSerializer(serializers.ModelSerializer):
+    """
+    Read only light serializer for Order export.
+    """
+
+    owner = serializers.SerializerMethodField(read_only=True)
+
+    class Meta:
+        model = models.Order
+        fields = (
+            "id",
+            "created_on",
+            "owner",
+            "total",
+        )
+        read_only_fields = fields
+
+    def get_owner(self, instance) -> str:
+        """
+        Return the full name of the order's owner if available,
+        otherwise fallback to the username
+        """
+        return instance.owner.get_full_name() or instance.owner.username
+
+
 class AdminEnrollmentLightSerializer(serializers.ModelSerializer):
     """
     Light Serializer for Enrollment model

src/backend/joanie/tests/core/api/admin/orders/test_export.py

@@ -0,0 +1,68 @@
+"""Test suite for the admin orders API export endpoint."""
+
+from http import HTTPStatus
+
+from django.test import TestCase
+
+from joanie.core import factories
+from joanie.tests import format_date
+
+
+class OrdersAdminApiExportTestCase(TestCase):
+    """Test suite for the admin orders API export endpoint."""
+
+    maxDiff = None
+
+    def test_api_admin_orders_export_csv_anonymous_user(self):
+        """
+        Anonymous users should not be able to export orders as CSV.
+        """
+        response = self.client.get("/api/v1.0/admin/orders/export/")
+
+        self.assertEqual(response.status_code, HTTPStatus.UNAUTHORIZED)
+
+    def test_api_admin_orders_export_csv_lambda_user(self):
+        """
+        Lambda users should not be able to export orders as CSV.
+        """
+        admin = factories.UserFactory(is_staff=False, is_superuser=False)
+        self.client.login(username=admin.username, password="password")
+
+        response = self.client.get("/api/v1.0/admin/orders/export/")
+
+        self.assertEqual(response.status_code, HTTPStatus.FORBIDDEN)
+
+    def test_api_admin_orders_export_csv(self):
+        """
+        Admin users should be able to export orders as CSV.
+        """
+        orders = factories.OrderFactory.create_batch(3)
+        admin = factories.UserFactory(is_staff=True, is_superuser=True)
+        self.client.login(username=admin.username, password="password")
+
+        response = self.client.get("/api/v1.0/admin/orders/export/")
+
+        self.assertEqual(response.status_code, HTTPStatus.OK)
+        self.assertEqual(response["Content-Type"], "text/csv")
+        self.assertEqual(
+            response["Content-Disposition"],
+            'attachment; filename="orders.csv"',
+        )
+        csv_content = response.content.decode().splitlines()
+        csv_header = csv_content.pop(0)
+        self.assertEqual(
+            csv_header.split(","),
+            [
+                "id",
+                "created_on",
+                "owner",
+                "total",
+            ],
+        )
+
+        for order, csv_line in zip(orders, csv_content, strict=False):
+            csv_row = csv_line.split(",")
+            self.assertEqual(csv_row[0], str(order.id))
+            self.assertEqual(csv_row[1], format_date(order.created_on))
+            self.assertEqual(csv_row[2], order.owner.username)
+            self.assertEqual(csv_row[3], str(order.total))

src/backend/joanie/tests/swagger/admin-swagger.json

@@ -3192,6 +3192,43 @@
                 }
             }
         },
+        "/api/v1.0/admin/orders/export/": {
+            "get": {
+                "operationId": "orders_export_retrieve",
+                "description": "Export orders to a CSV file.",
+                "tags": [
+                    "orders"
+                ],
+                "security": [
+                    {
+                        "cookieAuth": []
+                    }
+                ],
+                "responses": {
+                    "200": {
+                        "content": {
+                            "text/csv": {
+                                "schema": {
+                                    "type": "object",
+                                    "additionalProperties": {}
+                                }
+                            }
+                        },
+                        "description": ""
+                    },
+                    "404": {
+                        "content": {
+                            "application/json": {
+                                "schema": {
+                                    "$ref": "#/components/schemas/ErrorResponse"
+                                }
+                            }
+                        },
+                        "description": ""
+                    }
+                }
+            }
+        },
         "/api/v1.0/admin/organizations/": {
             "get": {
                 "operationId": "organizations_list",