First steps

src/pretix/base/email.py

@@ -2,12 +2,15 @@ import logging
 from smtplib import SMTPRecipientsRefused, SMTPSenderRefused
 
 from django.core.mail.backends.smtp import EmailBackend
+from django.utils.translation import ugettext_lazy as _
+from i18nfield.forms import I18nFormField, I18nTextarea
+
+from pretix.base.validators import PlaceholderValidator
 
 logger = logging.getLogger('pretix.base.email')
 
 
 class CustomSMTPBackend(EmailBackend):
-
     def test(self, from_addr):
         try:
             self.open()
@@ -24,3 +27,72 @@ class CustomSMTPBackend(EmailBackend):
                 raise SMTPRecipientsRefused(senderrs)
         finally:
             self.close()
+
+
+class MailTemplateRenderer:
+    def __init__(self, placeholders: list):
+        self.placeholders = placeholders
+
+    def formfield(self, **kwargs):
+        defaults = {
+            'required': False,
+            'widget': I18nTextarea,
+            'validators': [],
+            'help_text': ''
+        }
+        defaults.update(kwargs)
+        if defaults['help_text']:
+            defaults['help_text'] += ' '
+        defaults['help_text'] += _('Available placeholders: {list}').format(
+            list=', '.join(['{' + v + '}' for v in self.placeholders])
+        )
+        defaults['validators'].append(PlaceholderValidator(['{' + v + '}' for v in self.placeholders]))
+        return I18nFormField(**defaults)
+
+    def preview(self, text, **kwargs):
+        return text.format(**kwargs)
+
+    def render(self, text, values):
+        set_placeholders = set(values.keys())
+        expected_palceholders = set(self.placeholders)
+        if set_placeholders != expected_palceholders:
+            raise ValueError('Invalid placeholder set. Unknown placeholders: {}. Missing placeholders: {}'.format(
+                set_placeholders - expected_palceholders, expected_palceholders - set_placeholders
+            ))
+
+        return text.format_map(values)
+
+
+mail_text_order_placed = MailTemplateRenderer(
+    ['event', 'total', 'currency', 'date', 'payment_info', 'url', 'invoice_name', 'invoice_company']
+)
+mail_text_order_paid = MailTemplateRenderer(
+    ['event', 'url', 'invoice_name', 'invoice_company', 'payment_info']
+)
+mail_text_order_free = MailTemplateRenderer(
+    ['event', 'url', 'invoice_name', 'invoice_company']
+)
+mail_text_order_changed = MailTemplateRenderer(
+    ['event', 'url', 'invoice_name', 'invoice_company']
+)
+mail_text_resend_link = MailTemplateRenderer(
+    ['event', 'url', 'invoice_name', 'invoice_company']
+)
+mail_text_resend_all_links = MailTemplateRenderer(
+    ['event', 'orders']
+)
+mail_text_order_expire_warning = MailTemplateRenderer(
+    ['event', 'url', 'expire_date', 'invoice_name', 'invoice_company']
+)
+mail_text_waiting_list = MailTemplateRenderer(
+    ['event', 'url', 'product', 'hours', 'code']
+)
+mail_text_order_canceled = MailTemplateRenderer(
+    ['event', 'url', 'code']
+)
+mail_text_order_custom_mail = MailTemplateRenderer(
+    ['expire_date', 'event', 'code', 'date', 'url', 'invoice_name', 'invoice_company']
+)
+mail_text_download_reminder = MailTemplateRenderer(
+    ['event', 'url']
+)

src/pretix/base/forms/__init__.py

@@ -9,8 +9,6 @@ from hierarkey.forms import HierarkeyForm
 from pretix.base.models import Event
 from pretix.base.reldate import RelativeDateField, RelativeDateTimeField
 
-from .validators import PlaceholderValidator  # NOQA
-
 logger = logging.getLogger('pretix.plugins.ticketoutputpdf')
 
 

src/pretix/base/forms/validators.py

@@ -1,38 +0,0 @@
-import re
-
-from django.core.exceptions import ValidationError
-from django.core.validators import BaseValidator
-from django.utils.translation import ugettext_lazy as _
-from i18nfield.strings import LazyI18nString
-
-
-class PlaceholderValidator(BaseValidator):
-    """
-    Takes list of allowed placeholders,
-    validates form field by checking for placeholders,
-    which are not presented in taken list.
-    """
-
-    def __init__(self, limit_value):
-        super().__init__(limit_value)
-        self.limit_value = limit_value
-
-    def __call__(self, value):
-        if isinstance(value, LazyI18nString):
-            for l, v in value.data.items():
-                self.__call__(v)
-            return
-
-        data_placeholders = list(re.findall(r'({[\w\s]*})', value, re.X))
-        invalid_placeholders = []
-        for placeholder in data_placeholders:
-            if placeholder not in self.limit_value:
-                invalid_placeholders.append(placeholder)
-        if invalid_placeholders:
-            raise ValidationError(
-                _('Invalid placeholder(s): %(value)s'),
-                code='invalid',
-                params={'value': ", ".join(invalid_placeholders,)})
-
-    def clean(self, x):
-        return x

src/pretix/base/validators.py

@@ -1,6 +1,42 @@
+import re
+
 from django.core.exceptions import ValidationError
+from django.core.validators import BaseValidator
 from django.utils.deconstruct import deconstructible
 from django.utils.translation import ugettext_lazy as _
+from i18nfield.strings import LazyI18nString
+
+
+class PlaceholderValidator(BaseValidator):
+    """
+    Takes list of allowed placeholders,
+    validates form field by checking for placeholders,
+    which are not presented in taken list.
+    """
+
+    def __init__(self, limit_value):
+        super().__init__(limit_value)
+        self.limit_value = limit_value
+
+    def __call__(self, value):
+        if isinstance(value, LazyI18nString):
+            for l, v in value.data.items():
+                self.__call__(v)
+            return
+
+        data_placeholders = list(re.findall(r'({[\w\s]*})', value, re.X))
+        invalid_placeholders = []
+        for placeholder in data_placeholders:
+            if placeholder not in self.limit_value:
+                invalid_placeholders.append(placeholder)
+        if invalid_placeholders:
+            raise ValidationError(
+                _('Invalid placeholder(s): %(value)s'),
+                code='invalid',
+                params={'value': ", ".join(invalid_placeholders,)})
+
+    def clean(self, x):
+        return x
 
 
 class BlacklistValidator:

src/pretix/control/forms/event.py

@@ -8,13 +8,15 @@ from django.utils.translation import ugettext_lazy as _
 from i18nfield.forms import I18nFormField, I18nTextarea
 from pytz import common_timezones, timezone
 
-from pretix.base.forms import I18nModelForm, PlaceholderValidator, SettingsForm
+from pretix.base.forms import I18nModelForm, SettingsForm
 from pretix.base.models import Event, Organizer, TaxRule
 from pretix.base.models.event import EventMetaValue
 from pretix.base.reldate import RelativeDateField, RelativeDateTimeField
+from pretix.base.validators import PlaceholderValidator
 from pretix.control.forms import ExtFileField, SlugWidget
 from pretix.multidomain.urlreverse import build_absolute_uri
 from pretix.presale.style import get_fonts
+from pretix.base import email
 
 
 class EventWizardFoundationForm(forms.Form):
@@ -580,7 +582,6 @@ class MailSettingsForm(SettingsForm):
         label=_("Sender address"),
         help_text=_("Sender address for outgoing emails")
     )
-
     mail_text_signature = I18nFormField(
         label=_("Signature"),
         required=False,
@@ -588,50 +589,29 @@ class MailSettingsForm(SettingsForm):
         help_text=_("This will be attached to every email. Available placeholders: {event}"),
         validators=[PlaceholderValidator(['{event}'])]
     )
-
-    mail_text_order_placed = I18nFormField(
+    mail_text_order_placed = email.mail_text_order_placed.formfield(
         label=_("Text"),
         required=False,
-        widget=I18nTextarea,
-        help_text=_("Available placeholders: {event}, {total}, {currency}, {date}, {payment_info}, {url}, "
-                    "{invoice_name}, {invoice_company}"),
-        validators=[PlaceholderValidator(['{event}', '{total}', '{currency}', '{date}', '{payment_info}',
-                                          '{url}', '{invoice_name}', '{invoice_company}'])]
     )
-    mail_text_order_paid = I18nFormField(
+    mail_text_order_paid = email.mail_text_order_paid.formfield(
         label=_("Text"),
         required=False,
-        widget=I18nTextarea,
-        help_text=_("Available placeholders: {event}, {url}, {invoice_name}, {invoice_company}, {payment_info}"),
-        validators=[PlaceholderValidator(['{event}', '{url}', '{invoice_name}', '{invoice_company}', '{payment_info}'])]
     )
-    mail_text_order_free = I18nFormField(
+    mail_text_order_free = email.mail_text_order_free.formfield(
         label=_("Text"),
         required=False,
-        widget=I18nTextarea,
-        help_text=_("Available placeholders: {event}, {url}, {invoice_name}, {invoice_company}"),
-        validators=[PlaceholderValidator(['{event}', '{url}', '{invoice_name}', '{invoice_company}'])]
     )
-    mail_text_order_changed = I18nFormField(
+    mail_text_order_changed = email.mail_text_order_changed.formfield(
         label=_("Text"),
         required=False,
-        widget=I18nTextarea,
-        help_text=_("Available placeholders: {event}, {url}, {invoice_name}, {invoice_company}"),
-        validators=[PlaceholderValidator(['{event}', '{url}', '{invoice_name}', '{invoice_company}'])]
     )
-    mail_text_resend_link = I18nFormField(
+    mail_text_resend_link = email.mail_text_resend_link.formfield(
         label=_("Text (sent by admin)"),
         required=False,
-        widget=I18nTextarea,
-        help_text=_("Available placeholders: {event}, {url}, {invoice_name}, {invoice_company}"),
-        validators=[PlaceholderValidator(['{event}', '{url}', '{invoice_name}', '{invoice_company}'])]
     )
-    mail_text_resend_all_links = I18nFormField(
+    mail_text_resend_all_links = email.mail_text_resend_all_links.formfield(
         label=_("Text (requested by user)"),
         required=False,
-        widget=I18nTextarea,
-        help_text=_("Available placeholders: {event}, {orders}"),
-        validators=[PlaceholderValidator(['{event}', '{orders}'])]
     )
     mail_days_order_expire_warning = forms.IntegerField(
         label=_("Number of days"),
@@ -640,42 +620,25 @@ class MailSettingsForm(SettingsForm):
         help_text=_("This email will be sent out this many days before the order expires. If the "
                     "value is 0, the mail will never be sent.")
     )
-    mail_text_order_expire_warning = I18nFormField(
+    mail_text_order_expire_warning = email.mail_text_order_expire_warning.formfield(
         label=_("Text"),
         required=False,
-        widget=I18nTextarea,
-        help_text=_("Available placeholders: {event}, {url}, {expire_date}, {invoice_name}, {invoice_company}"),
-        validators=[PlaceholderValidator(['{event}', '{url}', '{expire_date}', '{invoice_name}', '{invoice_company}'])]
     )
-    mail_text_waiting_list = I18nFormField(
+    mail_text_waiting_list = email.mail_text_waiting_list.formfield(
         label=_("Text"),
         required=False,
-        widget=I18nTextarea,
-        help_text=_("Available placeholders: {event}, {url}, {product}, {hours}, {code}"),
-        validators=[PlaceholderValidator(['{event}', '{url}', '{product}', '{hours}', '{code}'])]
     )
-    mail_text_order_canceled = I18nFormField(
+    mail_text_order_canceled = email.mail_text_order_canceled.formfield(
         label=_("Text"),
         required=False,
-        widget=I18nTextarea,
-        help_text=_("Available placeholders: {event}, {code}, {url}"),
-        validators=[PlaceholderValidator(['{event}', '{code}', '{url}'])]
     )
-    mail_text_order_custom_mail = I18nFormField(
+    mail_text_order_custom_mail = email.mail_text_order_custom_mail.formfield(
         label=_("Text"),
         required=False,
-        widget=I18nTextarea,
-        help_text=_("Available placeholders: {expire_date}, {event}, {code}, {date}, {url}, "
-                    "{invoice_name}, {invoice_company}"),
-        validators=[PlaceholderValidator(['{expire_date}', '{event}', '{code}', '{date}', '{url}',
-                                          '{invoice_name}', '{invoice_company}'])]
     )
-    mail_text_download_reminder = I18nFormField(
+    mail_text_download_reminder = email.mail_text_download_reminder.formfield(
         label=_("Text"),
         required=False,
-        widget=I18nTextarea,
-        help_text=_("Available placeholders: {event}, {url}"),
-        validators=[PlaceholderValidator(['{event}', '{url}'])]
     )
     mail_days_download_reminder = forms.IntegerField(
         label=_("Number of days"),

src/pretix/control/forms/orders.py

@@ -6,12 +6,14 @@ from django.utils.formats import localize
 from django.utils.timezone import now
 from django.utils.translation import pgettext_lazy, ugettext_lazy as _
 
-from pretix.base.forms import I18nModelForm, PlaceholderValidator
+from pretix.base.email import mail_text_order_custom_mail
+from pretix.base.forms import I18nModelForm
 from pretix.base.models import (
     InvoiceAddress, Item, ItemAddOn, Order, OrderPosition,
 )
 from pretix.base.models.event import SubEvent
 from pretix.base.services.pricing import get_price
+from pretix.base.validators import PlaceholderValidator
 
 
 class ExtendForm(I18nModelForm):
@@ -269,13 +271,9 @@ class OrderMailForm(forms.Form):
             initial=order.email
         )
         self.fields['sendto'].widget.attrs['readonly'] = 'readonly'
-        self.fields['message'] = forms.CharField(
+        self.fields['message'] = mail_text_order_custom_mail.formfield(
             label=_("Message"),
             required=True,
             widget=forms.Textarea,
             initial=order.event.settings.mail_text_order_custom_mail.localize(order.locale),
-            help_text=_("Available placeholders: {expire_date}, {event}, {code}, {date}, {url}, "
-                        "{invoice_name}, {invoice_company}"),
-            validators=[PlaceholderValidator(['{expire_date}', '{event}', '{code}', '{date}', '{url}',
-                                              '{invoice_name}', '{invoice_company}'])]
         )

src/pretix/plugins/sendmail/email.py

@@ -0,0 +1,6 @@
+from pretix.base.email import MailTemplateRenderer
+
+mail_text_sendmail = MailTemplateRenderer(
+    ['expire_date', 'event', 'code', 'date', 'url', 'invoice_name', 'invoice_company']
+)
+

src/pretix/plugins/sendmail/forms.py

@@ -2,9 +2,9 @@ from django import forms
 from django.utils.translation import pgettext_lazy, ugettext_lazy as _
 from i18nfield.forms import I18nFormField, I18nTextarea, I18nTextInput
 
-from pretix.base.forms import PlaceholderValidator
 from pretix.base.models import Order
 from pretix.base.models.event import SubEvent
+from pretix.plugins.sendmail.email import mail_text_sendmail
 
 
 class MailForm(forms.Form):
@@ -25,13 +25,9 @@ class MailForm(forms.Form):
             widget=I18nTextInput, required=True,
             locales=event.settings.get('locales')
         )
-        self.fields['message'] = I18nFormField(
+        self.fields['message'] = mail_text_sendmail.formfield(
             widget=I18nTextarea, required=True,
             locales=event.settings.get('locales'),
-            help_text=_("Available placeholders: {expire_date}, {event}, {code}, {date}, {url}, "
-                        "{invoice_name}, {invoice_company}"),
-            validators=[PlaceholderValidator(['{expire_date}', '{event}', '{code}', '{date}', '{url}',
-                                              '{invoice_name}', '{invoice_company}'])]
         )
         choices = list(Order.STATUS_CHOICE)
         if not event.settings.get('payment_term_expire_automatically', as_type=bool):

src/pretix/plugins/sendmail/views.py

@@ -17,6 +17,7 @@ from pretix.base.models.event import SubEvent
 from pretix.base.services.mail import SendMailException, mail
 from pretix.control.permissions import EventPermissionRequiredMixin
 from pretix.multidomain.urlreverse import build_absolute_uri
+from pretix.plugins.sendmail.email import mail_text_sendmail
 
 from . import forms
 
@@ -82,8 +83,8 @@ class SenderView(EventPermissionRequiredMixin, FormView):
                     self.output[l] = []
                     self.output[l].append(
                         _('Subject: {subject}').format(subject=form.cleaned_data['subject'].localize(l)))
-                    message = form.cleaned_data['message'].localize(l)
-                    preview_text = message.format(
+                    preview_text = mail_text_sendmail.preview(
+                        text=form.cleaned_data['message'].localize(l),
                         code='ORDER1234',
                         event=self.request.event.name,
                         date=date_format(now(), 'SHORT_DATE_FORMAT'),