Email preview: Include prefix in subject (#4395)

src/pretix/base/services/mail.py

@@ -58,6 +58,7 @@ from django.core.mail import (
 from django.core.mail.message import SafeMIMEText
 from django.db import transaction
 from django.template.loader import get_template
+from django.utils.html import escape
 from django.utils.timezone import now, override
 from django.utils.translation import gettext as _, pgettext
 from django_scopes import scope, scopes_disabled
@@ -109,6 +110,22 @@ def clean_sender_name(sender_name: str) -> str:
     return sender_name
 
 
+def prefix_subject(settings_holder, subject, highlight=False):
+    prefix = settings_holder.settings.get('mail_prefix')
+    if prefix and prefix.startswith('[') and prefix.endswith(']'):
+        prefix = prefix[1:-1]
+    if prefix:
+        prefix = f"[{prefix}]"
+        if highlight:
+            prefix = '<span class="placeholder" title="{}">{}</span>'.format(
+                _('This prefix has been set in your event or organizer settings.'),
+                escape(prefix)
+            )
+
+        subject = f"{prefix} {subject}"
+    return subject
+
+
 def mail(email: Union[str, Sequence[str]], subject: str, template: Union[str, LazyI18nString],
          context: Dict[str, Any] = None, event: Event = None, locale: str = None, order: Order = None,
          position: OrderPosition = None, *, headers: dict = None, sender: str = None, organizer: Organizer = None,
@@ -240,11 +257,7 @@ def mail(email: Union[str, Sequence[str]], subject: str, template: Union[str, La
                     and settings_holder.settings.contact_mail and not headers.get('Reply-To'):
                 headers['Reply-To'] = settings_holder.settings.contact_mail
 
-            prefix = settings_holder.settings.get('mail_prefix')
+            subject = prefix_subject(settings_holder, subject)
-            if prefix and prefix.startswith('[') and prefix.endswith(']'):
-                prefix = prefix[1:-1]
-            if prefix:
-                subject = "[%s] %s" % (prefix, subject)
 
             body_plain += "\r\n\r\n-- \r\n"
 

src/pretix/control/views/event.py

@@ -98,6 +98,7 @@ from ...base.i18n import language
 from ...base.models.items import (
     Item, ItemCategory, ItemMetaProperty, Question, Quota,
 )
+from ...base.services.mail import prefix_subject
 from ...base.settings import LazyI18nStringList
 from ...helpers.compat import CompatDeleteView
 from ...helpers.format import format_map
@@ -746,9 +747,9 @@ class MailSettingsPreview(EventPermissionRequiredMixin, View):
                     with language(self.supported_locale[idx], self.request.event.settings.region):
                         try:
                             if k.startswith('mail_subject_'):
-                                msgs[self.supported_locale[idx]] = format_map(
+                                msgs[self.supported_locale[idx]] = prefix_subject(self.request.event, format_map(
                                     bleach.clean(v), self.placeholders(preview_item), raise_on_missing=True
-                                )
+                                ), highlight=True)
                             else:
                                 msgs[self.supported_locale[idx]] = markdown_compile_email(
                                     format_map(v, self.placeholders(preview_item), raise_on_missing=True)

src/pretix/control/views/orders.py

@@ -62,8 +62,9 @@ from django.urls import reverse
 from django.utils import formats
 from django.utils.formats import date_format, get_format
 from django.utils.functional import cached_property
-from django.utils.html import conditional_escape
+from django.utils.html import conditional_escape, escape
 from django.utils.http import url_has_allowed_host_and_scheme
+from django.utils.safestring import mark_safe
 from django.utils.timezone import make_aware, now
 from django.utils.translation import gettext, gettext_lazy as _, ngettext
 from django.views.generic import (
@@ -94,7 +95,9 @@ from pretix.base.services.invoices import (
     invoice_qualified, regenerate_invoice,
 )
 from pretix.base.services.locking import LockTimeoutException
-from pretix.base.services.mail import SendMailException, render_mail
+from pretix.base.services.mail import (
+    SendMailException, prefix_subject, render_mail,
+)
 from pretix.base.services.orders import (
     OrderChangeManager, OrderError, approve_order, cancel_order, deny_order,
     extend_order, mark_order_expired, mark_order_refunded,
@@ -2304,7 +2307,9 @@ class OrderSendMail(EventPermissionRequiredMixin, OrderViewMixin, FormView):
         email_content = render_mail(email_template, email_context)
         if self.request.POST.get('action') == 'preview':
             self.preview_output = {
-                'subject': _('Subject: {subject}').format(subject=email_subject),
+                'subject': mark_safe(_('Subject: {subject}').format(
+                    subject=prefix_subject(order.event, escape(email_subject), highlight=True)
+                )),
                 'html': markdown_compile_email(email_content)
             }
             return self.get(self.request, *self.args, **self.kwargs)
@@ -2369,7 +2374,9 @@ class OrderPositionSendMail(OrderSendMail):
         email_content = render_mail(email_template, email_context)
         if self.request.POST.get('action') == 'preview':
             self.preview_output = {
-                'subject': _('Subject: {subject}').format(subject=email_subject),
+                'subject': mark_safe(_('Subject: {subject}').format(
+                    subject=prefix_subject(position.order.event, escape(email_subject), highlight=True))
+                ),
                 'html': markdown_compile_email(email_content)
             }
             return self.get(self.request, *self.args, **self.kwargs)

src/pretix/control/views/organizer.py

@@ -90,7 +90,7 @@ from pretix.base.models.orders import CancellationRequest
 from pretix.base.models.organizer import SalesChannel, TeamAPIToken
 from pretix.base.payment import PaymentException
 from pretix.base.services.export import multiexport, scheduled_organizer_export
-from pretix.base.services.mail import SendMailException, mail
+from pretix.base.services.mail import SendMailException, mail, prefix_subject
 from pretix.base.signals import register_multievent_data_exporters
 from pretix.base.templatetags.rich_text import markdown_compile_email
 from pretix.base.views.tasks import AsyncAction
@@ -351,8 +351,11 @@ class MailSettingsPreview(OrganizerPermissionRequiredMixin, View):
                 if idx in self.supported_locale:
                     with language(self.supported_locale[idx], self.request.organizer.settings.region):
                         if k.startswith('mail_subject_'):
-                            msgs[self.supported_locale[idx]] = format_map(bleach.clean(v),
+                            msgs[self.supported_locale[idx]] = prefix_subject(
-                                                                          self.placeholders(preview_item))
+                                self.request.organizer,
+                                format_map(bleach.clean(v), self.placeholders(preview_item)),
+                                highlight=True,
+                            )
                         else:
                             msgs[self.supported_locale[idx]] = markdown_compile_email(
                                 format_map(v, self.placeholders(preview_item))

src/pretix/control/views/vouchers.py

@@ -64,6 +64,7 @@ from pretix.base.models import (
     CartPosition, LogEntry, Voucher, WaitingListEntry,
 )
 from pretix.base.models.vouchers import generate_codes
+from pretix.base.services.mail import prefix_subject
 from pretix.base.services.vouchers import vouchers_send
 from pretix.base.templatetags.rich_text import markdown_compile_email
 from pretix.base.views.tasks import AsyncFormView
@@ -572,7 +573,11 @@ class VoucherBulkMailPreview(EventPermissionRequiredMixin, View):
             return HttpResponseBadRequest(_('invalid item'))
         msgs = {}
         if "subject" in preview_item:
-            msgs["all"] = format_map(bleach.clean(request.POST.get(preview_item, "")), self.placeholders(preview_item))
+            msgs["all"] = prefix_subject(
+                self.request.event,
+                format_map(bleach.clean(request.POST.get(preview_item, "")), self.placeholders(preview_item)),
+                highlight=True
+            )
         else:
             msgs["all"] = markdown_compile_email(
                 format_map(request.POST.get(preview_item), self.placeholders(preview_item))

src/pretix/plugins/sendmail/views.py

@@ -61,6 +61,7 @@ from pretix.plugins.sendmail.tasks import (
     send_mails_to_orders, send_mails_to_waitinglist,
 )
 
+from ...base.services.mail import prefix_subject
 from ...helpers.format import format_map
 from ...helpers.models import modelcopy
 from . import forms
@@ -197,7 +198,7 @@ class BaseSenderView(EventPermissionRequiredMixin, FormView):
                         )
 
                     subject = bleach.clean(form.cleaned_data['subject'].localize(l), tags=[])
-                    preview_subject = format_map(subject, context_dict)
+                    preview_subject = prefix_subject(self.request.event, format_map(subject, context_dict), highlight=True)
                     message = form.cleaned_data['message'].localize(l)
                     preview_text = markdown_compile_email(format_map(message, context_dict))
 
@@ -612,7 +613,7 @@ class CreateRule(EventPermissionRequiredMixin, CreateView):
                         )
 
                     subject = bleach.clean(form.cleaned_data['subject'].localize(l), tags=[])
-                    preview_subject = format_map(subject, context_dict)
+                    preview_subject = prefix_subject(self.request.event, format_map(subject, context_dict), highlight=True)
                     template = form.cleaned_data['template'].localize(l)
                     preview_text = markdown_compile_email(format_map(template, context_dict))
 
@@ -688,7 +689,7 @@ class UpdateRule(EventPermissionRequiredMixin, UpdateView):
                     )
 
                 subject = bleach.clean(self.object.subject.localize(lang), tags=[])
-                preview_subject = format_map(subject, placeholders)
+                preview_subject = prefix_subject(self.request.event, format_map(subject, placeholders), highlight=True)
                 template = self.object.template.localize(lang)
                 preview_text = markdown_compile_email(format_map(template, placeholders))