Adding Ticket model to be able to discern tickets from products.

requirements/base.txt

@@ -5,3 +5,5 @@ django-environ>=0.4.0
 psycopg2>=2.6.1
 PyPDF2>=1.25.1
 django-wkhtmltopdf>=3.0.0
+Pillow==3.2.0
+qrcode==5.3

shop/admin.py

@@ -1,18 +1,19 @@
 from django.contrib import admin
 
-from .models import Order, ProductCategory, Product, OrderProductRelation, EpayCallback, EpayPayment
+from . import models
 
-admin.site.register(EpayCallback)
-admin.site.register(EpayPayment)
+admin.site.register(models.EpayCallback)
+admin.site.register(models.EpayPayment)
 
-@admin.register(ProductCategory)
+
+@admin.register(models.ProductCategory)
 class ProductCategoryAdmin(admin.ModelAdmin):
     list_display = [
         'name',
     ]
 
 
-@admin.register(Product)
+@admin.register(models.Product)
 class ProductAdmin(admin.ModelAdmin):
     list_display = [
         'name',
@@ -23,10 +24,10 @@ class ProductAdmin(admin.ModelAdmin):
 
 
 class ProductInline(admin.TabularInline):
-    model = OrderProductRelation
+    model = models.OrderProductRelation
 
 
-@admin.register(Order)
+@admin.register(models.Order)
 class OrderAdmin(admin.ModelAdmin):
     list_display = [
         'user',
@@ -46,3 +47,7 @@ class OrderAdmin(admin.ModelAdmin):
 
     inlines = [ProductInline]
 
+
+@admin.register(models.Ticket)
+class TicketAdmin(admin.ModelAdmin):
+    pass

shop/migrations/0012_ticket.py

@@ -0,0 +1,30 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.6 on 2016-05-23 15:08
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+import uuid
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('shop', '0011_auto_20160517_1902'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Ticket',
+            fields=[
+                ('created', models.DateTimeField(auto_now_add=True)),
+                ('updated', models.DateTimeField(auto_now=True)),
+                ('uuid', models.UUIDField(default=uuid.uuid4, editable=False, primary_key=True, serialize=False)),
+                ('order', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='shop.Order')),
+                ('product', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='shop.Product')),
+            ],
+            options={
+                'abstract': False,
+            },
+        ),
+    ]

shop/migrations/0013_ticket_qrcode_base64.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.6 on 2016-05-25 16:58
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('shop', '0012_ticket'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='ticket',
+            name='qrcode_base64',
+            field=models.TextField(blank=True, null=True),
+        ),
+    ]

shop/migrations/0014_ticket_name.py

@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.6 on 2016-05-25 17:02
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('shop', '0013_ticket_qrcode_base64'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='ticket',
+            name='name',
+            field=models.CharField(default='', help_text=b'Name of the person this ticket belongs to. This can be different from the buying user.', max_length=100),
+            preserve_default=False,
+        ),
+    ]

shop/models.py

@@ -1,3 +1,4 @@
+from django.conf import settings
 from django.db import models
 from django.db.models.aggregates import Sum
 from django.contrib.postgres.fields import DateTimeRangeField, JSONField
@@ -8,6 +9,12 @@ from django.core.urlresolvers import reverse_lazy
 from bornhack.utils import CreatedUpdatedModel, UUIDModel
 from .managers import ProductQuerySet
 
+import hashlib
+import io
+import base64
+
+import qrcode
+
 
 class Order(CreatedUpdatedModel):
 
@@ -207,3 +214,47 @@ class Invoice(CreatedUpdatedModel):
             self.sent_to_customer,
         )
 
+
+class Ticket(CreatedUpdatedModel, UUIDModel):
+    order = models.ForeignKey('shop.Order')
+    product = models.ForeignKey('shop.Product')
+    qrcode_base64 = models.TextField(null=True, blank=True)
+
+    name = models.CharField(
+        max_length=100,
+        help_text=(
+            'Name of the person this ticket belongs to. '
+            'This can be different from the buying user.'
+        ),
+    )
+
+    def __str__(self):
+        return 'Ticket {user} {product}'.format(
+            user=self.order.user,
+            product=self.product
+        )
+
+    def save(self, **kwargs):
+        super(Ticket, self).save(**kwargs)
+        self.qrcode_base64 = self.get_qr_code()
+        super(Ticket, self).save(**kwargs)
+
+    def get_token(self):
+        return hashlib.sha256(
+            '{ticket_id}{user_id}{secret_key}'.format(
+                ticket_id=self.pk,
+                user_id=self.order.user.pk,
+                secret_key=settings.SECRET_KEY,
+            )
+        ).hexdigest()
+
+    def get_qr_code(self):
+        qr = qrcode.make(self.get_token())
+        file_like = io.BytesIO()
+        qr.save(file_like)
+        qrcode_base64 = base64.b64encode(file_like.getvalue())
+        return qrcode_base64
+
+    def get_qr_code_url(self):
+        return 'data:image/png;base64,{}'.format(self.qrcode_base64)
+