Add QR codes for pseudonymization ID

src/pretix/api/serializers/order.py

@@ -128,7 +128,7 @@ class OrderPositionSerializer(I18nAwareModelSerializer):
         model = OrderPosition
         fields = ('id', 'order', 'positionid', 'item', 'variation', 'price', 'attendee_name', 'attendee_email',
                   'voucher', 'tax_rate', 'tax_value', 'secret', 'addon_to', 'subevent', 'checkins', 'downloads',
-                  'answers', 'tax_rule')
+                  'answers', 'tax_rule', 'pseudonymization_id')
 
 
 class OrderFeeSerializer(I18nAwareModelSerializer):

src/pretix/base/migrations/0093_auto_20180528_1432.py

@@ -0,0 +1,45 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.13 on 2018-05-28 14:32
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+from django.utils.crypto import get_random_string
+
+
+def set_pids(apps, schema_editor):
+    OrderPosition = apps.get_model('pretixbase', 'OrderPosition')  # noqa
+    taken = set()
+    charset = list('ABCDEFGHJKLMNPQRSTUVWXYZ3789')
+    for op in OrderPosition.objects.iterator():
+        while True:
+            code = get_random_string(length=10, allowed_chars=charset)
+            if code not in taken:
+                op.pseudonymization_id = code
+                taken.add(code)
+                break
+        op.save(update_fields=['pseudonymization_id'])
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0092_auto_20180511_1224'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='orderposition',
+            name='pseudonymization_id',
+            field=models.CharField(db_index=True, max_length=16, null=True, unique=True),
+        ),
+        migrations.RunPython(
+            set_pids,
+            migrations.RunPython.noop,
+        ),
+        migrations.AlterField(
+            model_name='orderposition',
+            name='pseudonymization_id',
+            field=models.CharField(db_index=True, default='', max_length=16, unique=True),
+            preserve_default=False,
+        ),
+    ]

src/pretix/base/models/orders.py

@@ -835,6 +835,11 @@ class OrderPosition(AbstractPosition):
         verbose_name=_('Tax value')
     )
     secret = models.CharField(max_length=64, default=generate_position_secret, db_index=True)
+    pseudonymization_id = models.CharField(
+        max_length=16,
+        unique=True,
+        db_index=True
+    )
 
     class Meta:
         verbose_name = _("Order position")
@@ -916,8 +921,24 @@ class OrderPosition(AbstractPosition):
         if self.pk is None:
             while OrderPosition.objects.filter(secret=self.secret).exists():
                 self.secret = generate_position_secret()
+
+        if not self.pseudonymization_id:
+            self.assign_pseudonymization_id()
+
         return super().save(*args, **kwargs)
 
+    def assign_pseudonymization_id(self):
+        # This omits some character pairs completely because they are hard to read even on screens (1/I and O/0)
+        # and includes only one of two characters for some pairs because they are sometimes hard to distinguish in
+        # handwriting (2/Z, 4/A, 5/S, 6/G). This allows for better detection e.g. in incoming wire transfers that
+        # might include OCR'd handwritten text
+        charset = list('ABCDEFGHJKLMNPQRSTUVWXYZ3789')
+        while True:
+            code = get_random_string(length=10, allowed_chars=charset)
+            if not OrderPosition.objects.filter(pseudonymization_id=code).exists():
+                self.pseudonymization_id = code
+                return
+
 
 class CartPosition(AbstractPosition):
     """

src/pretix/base/pdf.py

@@ -211,8 +211,14 @@ class Renderer:
                 pdfmetrics.registerFont(TTFont(family + ' B I', finders.find(styles['bolditalic']['truetype'])))
 
     def _draw_barcodearea(self, canvas: Canvas, op: OrderPosition, o: dict):
+        content = o.get('content', 'secret')
+        if content == 'secret':
+            content = op.secret
+        elif content == 'pseudonymization_id':
+            content = op.pseudonymization_id
+
         reqs = float(o['size']) * mm
-        qrw = QrCodeWidget(op.secret, barLevel='H', barHeight=reqs, barWidth=reqs)
+        qrw = QrCodeWidget(content, barLevel='H', barHeight=reqs, barWidth=reqs)
         d = Drawing(reqs, reqs)
         d.add(qrw)
         qr_x = float(o['left']) * mm

src/pretix/control/templates/pretixcontrol/pdf/index.html

@@ -317,9 +317,15 @@
                         <span class="fa fa-font"></span>
                         {% trans "Text" %}
                     </button>
-                    <button class="btn btn-default btn-block" id="editor-add-qrcode" disabled>
+                    <button class="btn btn-default btn-block" id="editor-add-qrcode" data-content="secret" disabled>
                         <span class="fa fa-qrcode"></span>
-                        {% trans "QR code area" %}
+                        {% trans "QR code for Check-In" %}
+                    </button>
+                    <button class="btn btn-default btn-block" id="editor-add-qrcode-lead"
+                            data-content="pseudonymization_id"
+                            disabled>
+                        <span class="fa fa-qrcode"></span>
+                        {% trans "QR code for Lead Scanning" %}
                     </button>
                 </div>
             </div>

src/pretix/static/pretixcontrol/js/ui/editor.js

@@ -18,7 +18,11 @@ fabric.Barcodearea = fabric.util.createClass(fabric.Rect, {
 
         ctx.font = '16px Helvetica';
         ctx.fillStyle = '#fff';
-        ctx.fillText(gettext('QR Code'), -this.width / 2, -this.height / 2 + 20);
+        if (this.content === "pseudonymization_id") {
+            ctx.fillText(gettext('Lead Scan QR'), -this.width / 2, -this.height / 2 + 20);
+        } else {
+            ctx.fillText(gettext('Check-in QR'), -this.width / 2, -this.height / 2 + 20);
+        }
     },
 });
 fabric.Barcodearea.fromObject = function (object, callback, forceAsync) {
@@ -112,7 +116,8 @@ var editor = {
                     type: "barcodearea",
                     left: editor._px2mm(left).toFixed(2),
                     bottom: editor._px2mm(editor.pdf_viewport.height - o.height * o.scaleY - top).toFixed(2),
-                    size: editor._px2mm(o.height * o.scaleY).toFixed(2)
+                    size: editor._px2mm(o.height * o.scaleY).toFixed(2),
+                    content: o.content,
                 });
             }
         }
@@ -122,6 +127,7 @@ var editor = {
     _add_from_data: function (d) {
         if (d.type === "barcodearea") {
             o = editor._add_qrcode();
+            o.content = d.content;
             o.scaleToHeight(editor._mm2px(d.size));
         } else if (d.type === "textarea" || o.type === "text") {
             o = editor._add_text();
@@ -418,6 +424,7 @@ var editor = {
             lockRotation: true,
             lockUniScaling: true,
             fill: '#666',
+            content: $(this).attr("data-content"),
         });
         rect.setControlsVisibility({'mtr': false});
         editor.fabric.add(rect);
@@ -645,7 +652,7 @@ var editor = {
         editor.$fcv = $("#fabric-canvas");
         editor.$cva = $("#editor-canvas-area");
         editor._load_pdf();
-        $("#editor-add-qrcode").click(editor._add_qrcode);
+        $("#editor-add-qrcode, #editor-add-qrcode-lead").click(editor._add_qrcode);
         $("#editor-add-text").click(editor._add_text);
         editor.$cva.get(0).tabIndex = 1000;
         editor.$cva.on("keydown", editor._on_keydown);