[#41] Allow users to download the user/planting guide for a payment

- backend changes

backend/requirements.txt

@@ -8,4 +8,6 @@ gunicorn==20.1.0
 pandas==1.5.3
 pdfkit==1.0.0
 PyPDF2==1.28.6
+redis==4.5.1
 celery[redis]==5.2.7
+stripe==5.2.0

backend/right_tree/api/admin.py

@@ -7,13 +7,42 @@ from right_tree.api import models
 from right_tree.api.resource_generation_utils import storage
 
 
+class ActivationKeySetFilter(admin.SimpleListFilter):
+    title = "key set"
+    parameter_name = "key_set"
+
+    def lookups(self, request, model_admin):
+        return [
+            (val, val) for val in models.ActivationKeySet.objects.values_list('name', flat=True)
+        ]
+
+    def queryset(self, request, queryset):
+        key_set = self.value()
+        return queryset.filter(key__key_set__name=key_set) if key_set else queryset
+
+
 class ZoneAdmin(admin.ModelAdmin):
     ordering = ['name', 'variant', 'refined_variant', 'id']
     search_fields = ['name', 'habitat__name', 'variant', 'refined_variant', 'id']
 
 
+class ActivationKeySetAdmin(admin.ModelAdmin):
+    list_display = ['name', 'size_display']
+
+    @admin.display(description="Size")
+    def size_display(self, obj):
+        size = obj.size
+        return size if size > 0 else None
+
+
+class ActivationKeyAdmin(admin.ModelAdmin):
+    list_display = ['key', 'creation_date', 'key_set', 'remaining_activations']
+    list_filter = ['creation_date', 'key_set']
+
+
 class QuestionnaireAdmin(admin.ModelAdmin):
-    list_display = ['address_display', 'location_display', 'soil_variant', 'ecological_district_display', 'habitat', 'zone']
+    list_display = ['address_display', 'location_display', 'soil_variant', 'ecological_district_display', 'habitat', 'zone', 'key_set_display']
+    list_filter = [ActivationKeySetFilter]
     actions = ['export']
 
     @admin.display(description="Address")
@@ -22,7 +51,7 @@ class QuestionnaireAdmin(admin.ModelAdmin):
 
     @admin.display(description="Location")
     def location_display(self, obj):
-        return f"({obj.location.x}, {obj.location.y})"
+        return f"({obj.location.x:.4f}, {obj.location.y:.4f})"
 
     @admin.display(description="Ecological District")
     def ecological_district_display(self, obj):
@@ -32,6 +61,11 @@ class QuestionnaireAdmin(admin.ModelAdmin):
             None,
         )
 
+    @admin.display(description="Key Set")
+    def key_set_display(self, obj):
+        if obj.key and obj.key.key_set:
+            return obj.key.key_set.name
+
     @admin.action(description="Export planting guides for selected questionnaires")
     def export(self, request, queryset):
         export = models.Export.objects.create(creation_date=timezone.now())
@@ -96,5 +130,7 @@ admin.site.register(models.HabitatImage)
 admin.site.register(models.Habitat)
 admin.site.register(models.Zone, ZoneAdmin)
 admin.site.register(models.ChristchurchRegion)
+admin.site.register(models.ActivationKey, ActivationKeyAdmin)
+admin.site.register(models.ActivationKeySet, ActivationKeySetAdmin)
 admin.site.register(models.Questionnaire, QuestionnaireAdmin)
 admin.site.register(models.Export, ExportAdmin)

backend/right_tree/api/migrations/0015_auto_20230306_1620.py

@@ -0,0 +1,40 @@
+# Generated by Django 3.2.17 on 2023-03-06 03:20
+
+from django.db import migrations, models
+import django.db.models.deletion
+import right_tree.api.models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('api', '0014_address_export_questionnaire'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='ActivationKeySet',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('creation_date', models.DateTimeField(auto_now_add=True)),
+                ('name', models.CharField(max_length=255, unique=True)),
+                ('size', models.PositiveSmallIntegerField()),
+                ('initial_activations', models.SmallIntegerField(default=1)),
+            ],
+        ),
+        migrations.CreateModel(
+            name='ActivationKey',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('key', models.CharField(default=right_tree.api.models.ActivationKey.key_default, max_length=20, unique=True)),
+                ('remaining_activations', models.SmallIntegerField(default=1)),
+                ('creation_date', models.DateTimeField(auto_now_add=True)),
+                ('key_set', models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, to='api.activationkeyset')),
+            ],
+        ),
+        migrations.AddField(
+            model_name='questionnaire',
+            name='key',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.PROTECT, to='api.activationkey'),
+        ),
+    ]

backend/right_tree/api/models.py

@@ -1,3 +1,6 @@
+import random
+import string
+
 from functools import cached_property
 from pathlib import Path
 
@@ -199,10 +202,39 @@ class Address(models.Model):
         managed = False
 
 
+class ActivationKeySet(models.Model):
+    creation_date = models.DateTimeField(auto_now_add=True)
+    name = models.CharField(max_length=255, unique=True)
+    size = models.PositiveSmallIntegerField()
+    initial_activations = models.SmallIntegerField(default=1)
+
+    def __str__(self):
+        return self.name
+
+
+class ActivationKey(models.Model):
+
+    def key_default():
+        return "".join(
+            random.choice(
+                [string.ascii_uppercase, string.digits][random.randint(0, 1)]
+            ) for _ in range(20)
+        )
+
+    key = models.CharField(max_length=20, unique=True, default=key_default)
+    key_set = models.ForeignKey(ActivationKeySet, on_delete=models.CASCADE, null=True)
+    remaining_activations = models.SmallIntegerField(default=1)
+    creation_date = models.DateTimeField(auto_now_add=True)
+
+    def __str__(self):
+        return self.key
+
+
 class Questionnaire(models.Model):
     location = models.PointField()
     soil_variant = models.ForeignKey(SoilVariant, on_delete=models.CASCADE)
     zone = models.ForeignKey(Zone, on_delete=models.CASCADE)
+    key = models.ForeignKey(ActivationKey, on_delete=models.PROTECT, null=True)
 
     @property
     def habitat(self):

backend/right_tree/api/redis.py

@@ -0,0 +1,6 @@
+import redis
+
+from django.conf import settings
+
+
+redis_client = redis.from_url(settings.REDIS_DJANGO_URL)

backend/right_tree/api/serializers.py

@@ -100,6 +100,7 @@ class AddressSerializer(serializers.Serializer):
 class QuestionnaireSerializer(serializers.ModelSerializer):
 
     soil_variant = serializers.CharField(max_length=10)
+    key = serializers.CharField(max_length=20, write_only=True)
 
     class Meta:
         model = Questionnaire
@@ -110,3 +111,11 @@ class QuestionnaireSerializer(serializers.ModelSerializer):
             return SoilVariant.objects.get(name__startswith=value)
         except SoilVariant.DoesNotExist as e:
             raise exceptions.ValidationError(e)
+
+    def validate_key(self, value):
+        try:
+            if (ak := ActivationKey.objects.get(key=value)).remaining_activations > 0:
+                return ak
+            raise exceptions.ValidationError("no remaining activations")
+        except ActivationKey.DoesNotExist as e:
+            raise exceptions.ValidationError(e)

backend/right_tree/api/signals.py

@@ -1,12 +1,31 @@
 from shutil import rmtree
 
-from django.db.models.signals import post_delete
+from django.db.models.signals import post_save, post_delete
 from django.dispatch import receiver
 
-from .models import Export
+from .models import Export, ActivationKey, ActivationKeySet, Questionnaire
 from .resource_generation_utils import storage
 
 
 @receiver(post_delete, sender=Export)
-def delete_export(sender, instance, *args, **kwargs):
+def delete_export(sender, instance, created, *args, **kwargs):
+    """Clean up created files on the filesystem when an export is deleted"""
     rmtree(storage.path(f"export_{instance.pk}"))
+
+
+@receiver(post_save, sender=ActivationKeySet)
+def create_keys(sender, instance, created, *args, **kwargs):
+    """Create n ActivationKey objects where n is the ActivationKeySet.size value"""
+    if created:
+        ActivationKey.objects.bulk_create([
+            ActivationKey(key_set=instance, remaining_activations=instance.initial_activations)
+            for _ in range(instance.size)
+        ])
+
+
+@receiver(post_save, sender=Questionnaire)
+def activate_key(sender, instance, created, *args, **kwargs):
+    """Consume one activation on the key associated with the created Questionnaire"""
+    if created and (key := instance.key):
+        key.remaining_activations -= 1
+        key.save()

backend/right_tree/api/views.py

@@ -1,15 +1,23 @@
-from django.http import HttpResponseBadRequest, FileResponse
-from django.shortcuts import get_object_or_404
+import json
+import stripe
+
+from datetime import timedelta
+
+from django.http import HttpResponse, HttpResponseNotAllowed, HttpResponseNotFound, HttpResponseBadRequest, FileResponse
+from django.shortcuts import get_object_or_404, redirect
+from django.urls import reverse
 from django.utils import timezone
 from django.utils.text import slugify
 from rest_framework import viewsets, permissions
+from rest_framework.decorators import action
 from rest_framework.response import Response
 
-from .models import Habitat, HabitatImage, Plant, EcologicalDistrictLayer, SoilOrder, Zone, Questionnaire
+from .models import Habitat, HabitatImage, Plant, EcologicalDistrictLayer, SoilOrder, Zone, Questionnaire, ActivationKey, ActivationKeySet
 from .serializers import HabitatImageSerializer, HabitatSerializer, PlantSerializer, SoilOrderSerializer, EcologicalDistrictLayerSerializer, AddressSerializer, ZoneSerializer, QuestionnaireSerializer
 from .filters import *
 from .wms_utils import get_address_from_coordinates, search_address
 from .resource_generation_utils import generate_csv, get_filter_values, serialize_plants_queryset, create_planting_guide_pdf, PLANTING_GUIDE_PDF_FILENAME, CSV_FILENAME, storage
+from .redis import redis_client
 
 
 class PlantViewSet(viewsets.ModelViewSet):
@@ -159,3 +167,83 @@ class QuestionnaireViewSet(viewsets.ModelViewSet):
     queryset = Questionnaire.objects.all()
     http_method_names = ("post",)
     permission_classes = [permissions.AllowAny]
+
+
+def validate_key(request):
+    """Checks if a given key value is valid"""
+    if request.method == "GET":
+        data = request.GET
+    elif request.method != "POST":
+        return HttpResponseNotAllowed()
+    else:
+        try:
+            data = request.POST or json.loads(request.body)
+        except json.JSONDecodeError as e:
+            return HttpResponseBadRequest(e)
+
+    key = data.get("key")
+
+    if not key:
+        return HttpResponseBadRequest("'key' not specified")
+
+    try:
+        if ActivationKey.objects.get(key=key).remaining_activations > 0:
+            return HttpResponse()
+    except ActivationKey.DoesNotExist:
+        pass
+
+    return HttpResponseNotFound()
+
+
+def activate_key(request):
+    """Adds a single activation to a given key if a Stripe payment has succeeded"""
+    redirect_url = "/apply"
+
+    try:
+        key = request.GET['key']
+        stripe_session_id = redis_client.getdel(key).decode()
+        stripe_session = stripe.checkout.Session.retrieve(stripe_session_id)
+        status = stripe_session.payment_status
+    except (KeyError, AttributeError):
+        return redirect(redirect_url)
+
+    match status:
+        case "paid":
+            ActivationKey.objects.create(
+                key=key,
+                key_set=ActivationKeySet.objects.get_or_create(name="Stripe", size=0)[0],
+            )
+            redirect_url += "?key=" + key
+        case "open":
+            stripe.checkout.Session.expire(stripe_session_id)
+
+    return redirect(redirect_url)
+
+
+def purchase_key(request):
+    """Generate a prospective key and redirect to the Stripe payment portal"""
+    key = ActivationKey.key_default()
+    redirect_url = request.build_absolute_uri(reverse(activate_key)) + f"?key={key}"
+    stripe_session = stripe.checkout.Session.create(
+        line_items=[
+            {
+                "price": "price_1Mh1I6GLlkkooLVio8W3TGkR",
+                "quantity": 1,
+            },
+        ],
+        automatic_tax={'enabled': True},
+        invoice_creation={
+            'enabled': True,
+            'invoice_data': {
+                'description': f'Your product code is {key}',
+                'rendering_options': {'amount_tax_display': 'include_inclusive_tax'},
+                'footer': 'BioSphere Capital Limited',
+            },
+        },
+        mode='payment',
+        success_url=redirect_url,
+        cancel_url=redirect_url,
+    )
+    redis_client.setex(key, timedelta(hours=8), stripe_session.id)
+
+    return redirect(stripe_session.url)

backend/right_tree/settings.py

@@ -11,6 +11,7 @@ https://docs.djangoproject.com/en/3.2/ref/settings/
 """
 
 import os
+import stripe
 from pathlib import Path
 
 # Build paths inside the project like this: BASE_DIR / 'subdir'.
@@ -150,6 +151,17 @@ CORS_ALLOW_HEADERS = [
     'access-control-allow-origin'
 ]
 
+# Redis configuration
+REDIS_HOST = os.getenv("REDIS_HOST", "redis")
+REDIS_PORT = int(os.getenv("REDIS_PORT", 6379))
+REDIS_PASSWORD = os.getenv("REDIS_PASSWORD", "redis")
+REDIS_BASE_URL = f"redis://:{REDIS_PASSWORD}@{REDIS_HOST}:{REDIS_PORT}"
+REDIS_CELERY_URL = REDIS_BASE_URL + "/0"
+REDIS_DJANGO_URL = REDIS_BASE_URL + "/1"
+
 # Celery configuration
 CELERY_TIMEZONE = TIME_ZONE
-CELERY_BROKER_URL = os.getenv("CELERY_BROKER_URL", "redis://redis:6379/0")
+CELERY_BROKER_URL = REDIS_CELERY_URL
+
+# Stripe payment processing
+stripe.api_key = os.environ['STRIPE_API_KEY']

backend/right_tree/urls.py

@@ -36,5 +36,8 @@ router.register(r'download/pdf', views.PDFDownloadView, basename='downloadpdf')
 urlpatterns = [
     path('admin/', admin.site.urls),
     path('api/', include(router.urls)),
+    path('api/key/validate/', views.validate_key),
+    path('api/key/activate/', views.activate_key),
+    path('api/key/purchase/', views.purchase_key),
     path('api-auth/', include('rest_framework.urls', namespace='rest_framework'))
 ]

docker-compose.yaml

@@ -70,12 +70,17 @@ services:
       - ./nginx.conf:/etc/nginx/nginx.conf:ro
       - ./backend/right_tree/staticfiles:/etc/nginx/html/staticfiles:ro
     ports:
-      - "9000:80"
+      - 80:80
 
   redis:
     image: redis:7.0.8
     restart: unless-stopped
     container_name: redis
+    volumes:
+      - ./redis.conf:/usr/local/etc/redis/redis.conf:ro
+    command:
+      - redis-server
+      - /usr/local/etc/redis/redis.conf
     expose:
       - "6379"
     healthcheck:

redis.conf

@@ -0,0 +1 @@
+requirepass "redis"