Fix #173 -- Context variables in sendmail plugin (#279)

* Add context variables to sendmail plugin
#173

* fixed date format

* add context variables to sendmail plugin

* timezone adjustment
#173

* partial preview

* preview raw message

* preview not formatted

* Add context variables to sendmail plugin. Add email preview
#173

* Add context variables to sendmail plugin. Add email preview for multiple locales
#173

* add context variables to sendmail plugin, and email preview for multiple locales
#173

* add context variables to sendmail plugin, and email preview for multiple locales

* order url link update
#173

src/pretix/plugins/sendmail/forms.py

@@ -19,7 +19,8 @@ class MailForm(forms.Form):
         )
         self.fields['message'] = I18nFormField(
             widget=I18nTextarea, required=True,
-            langcodes=event.settings.get('locales')
+            langcodes=event.settings.get('locales'),
+            help_text=_("Available placeholders: {due_date}, {event}, {order}, {order_date}, {order_url}")
         )
         choices = list(Order.STATUS_CHOICE)
         if not event.settings.get('payment_term_expire_automatically', as_type=bool):

src/pretix/plugins/sendmail/templates/pretixplugins/sendmail/send_form.html

@@ -10,7 +10,28 @@
             {% bootstrap_field form.sendto layout='horizontal' %}
             {% bootstrap_field form.subject layout='horizontal' %}
             {% bootstrap_field form.message layout='horizontal' %}
+            {% if request.method == "POST" %}
+            <fieldset>
+            <legend>{% trans "E-mail preview" %}</legend>
+
+                <div class="panel-body">
+                    {% for locale, segments in output.items %}
+                    <p>
+                        <strong>{% blocktrans %}For locale: {{ locale }}{% endblocktrans %}</strong>
+                    </p>
+                        {% for value in segments %}
+                        <p>
+                            {{ value|linebreaksbr }}
+                        </p>
+                        {% endfor %}
+                    {% endfor %}
+                </div>
+            </fieldset>
+            {% endif %}
             <div class="form-group submit-group">
+                <button type="submit" class="btn btn-default btn-save pull-left" name="action" value="preview">
+                {% trans "Preview email" %}
+                </button>
                 <button type="submit" class="btn btn-primary btn-save">
                     {% trans "Send" %}
                 </button>
@@ -18,4 +39,3 @@
         </form>
     {% endblock %}
 {% endblock %}
-

src/pretix/plugins/sendmail/views.py

@@ -1,15 +1,20 @@
 import logging
+from datetime import timedelta
+import pytz
 
 from django.contrib import messages
 from django.db.models import Q
 from django.shortcuts import redirect
+from django.utils.formats import date_format
 from django.utils.timezone import now
 from django.utils.translation import ugettext_lazy as _
 from django.views.generic import FormView
 
+from pretix.base.i18n import language
 from pretix.base.models import Order
 from pretix.base.services.mail import SendMailException, mail
 from pretix.control.permissions import EventPermissionRequiredMixin
+from pretix.multidomain.urlreverse import build_absolute_uri
 
 from . import forms
 
@@ -36,13 +41,44 @@ class SenderView(EventPermissionRequiredMixin, FormView):
         self.request.event.log_action('pretix.plugins.sendmail.sent', user=self.request.user, data=dict(
             form.cleaned_data))
 
+        tz = pytz.timezone(self.request.event.settings.timezone)
+
         failures = []
+        self.output = {}
         for o in orders:
-            try:
-                mail(o.email, form.cleaned_data['subject'], form.cleaned_data['message'],
-                     None, self.request.event, locale=o.locale, order=o)
-            except SendMailException:
-                failures.append(o.email)
+            if self.request.POST.get("action") == "preview":
+                for l in self.request.event.settings.locales:
+                    with language(l):
+                        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(
+                            order='ORDER1234',
+                            event=self.request.event.name,
+                            order_date=date_format(now(), 'SHORT_DATE_FORMAT'),
+                            due_date=date_format(now() + timedelta(days=7), 'SHORT_DATE_FORMAT'),
+                            order_url=build_absolute_uri(self.request.event, 'presale:event.order', kwargs={
+                                'order': 'ORDER1234',
+                                'secret': 'longrandomsecretabcdef123456'
+                            }))
+                        self.output[l].append(preview_text)
+                return self.get(self.request, *self.args, **self.kwargs)
+            else:
+                try:
+                    with language(o.locale):
+                        mail(o.email, form.cleaned_data['subject'], form.cleaned_data['message'],
+                             {
+                                 'event': o.event,
+                                 'order': o.code,
+                                 'order_date': date_format(o.datetime.astimezone(tz), 'SHORT_DATETIME_FORMAT'),
+                                 'due_date': date_format(o.expires, 'SHORT_DATE_FORMAT'),
+                                 'order_url': build_absolute_uri(o.event, 'presale:event.order', kwargs={
+                                     'order': 'ORDER1234',
+                                     'secret': 'longrandomsecretabcdef123456'
+                                 })},
+                             self.request.event, locale=o.locale, order=o)
+                except SendMailException:
+                    failures.append(o.email)
 
         if failures:
             messages.error(self.request, _('Failed to send mails to the following users: {}'.format(' '.join(failures))))
@@ -54,3 +90,8 @@ class SenderView(EventPermissionRequiredMixin, FormView):
             event=self.request.event.slug,
             organizer=self.request.event.organizer.slug
         )
+
+    def get_context_data(self, *args, **kwargs):
+        ctx = super().get_context_data(*args, **kwargs)
+        ctx['output'] = getattr(self, 'output', None)
+        return ctx