Issue #149: Extracted email messages to templates. Fixed some bugs, cleaned up some code.

dds_registration/admin.py

@@ -4,8 +4,8 @@
 from django.contrib import admin, messages
 from django.contrib.admin import SimpleListFilter
 from django.contrib.auth.admin import UserAdmin as BaseUserAdmin
-from django.db.models import Q
-from django.http import HttpResponse
+from django.db.models import Q, QuerySet
+from django.http import HttpRequest, HttpResponse
 
 from .forms import (
     EventAdminForm,
@@ -42,7 +42,7 @@ def lookups(self, request, model_admin):
             ("0", "No"),
         )
 
-    def queryset(self, request, queryset):
+    def queryset(self, request: HttpRequest, queryset: QuerySet):
         if self.value() == "1":
             return queryset.filter(is_staff=False, is_superuser=False)
         if self.value() == "0":
@@ -212,17 +212,17 @@ class PaymentAdmin(admin.ModelAdmin):
     actions = ["mark_invoice_paid", "email_invoices", "email_receipts", "download_invoices", "download_receipts"]
 
     @admin.action(description="Mark selected invoices paid")
-    def mark_invoice_paid(self, request, queryset):
+    def mark_invoice_paid(self, request: HttpRequest, queryset: QuerySet):
         for obj in queryset:
-            obj.mark_paid()
+            obj.mark_paid(request)
         self.message_user(
             request,
             f"{queryset.count()} invoices marked as paid",
             messages.SUCCESS,
         )
 
     @admin.action(description="Email unpaid invoices to user")
-    def email_invoices(self, request, queryset):
+    def email_invoices(self, request: HttpRequest, queryset: QuerySet):
         qs = queryset.filter(status__in=("CREATED", "ISSUED"))
         count = qs.count()
 
@@ -235,7 +235,7 @@ def email_invoices(self, request, queryset):
             return
 
         for obj in qs:
-            obj.email_invoice()
+            obj.email_invoice(request)
 
         self.message_user(
             request,
@@ -244,7 +244,7 @@ def email_invoices(self, request, queryset):
         )
 
     @admin.action(description="Download unpaid invoices")
-    def download_invoices(self, request, queryset):
+    def download_invoices(self, request: HttpRequest, queryset: QuerySet):
         qs = queryset.filter(status__in=("CREATED", "ISSUED"))
 
         if not qs.count():
@@ -266,7 +266,7 @@ def download_invoices(self, request, queryset):
         return response
 
     @admin.action(description="Email receipts for completed payments to user")
-    def email_receipts(self, request, queryset):
+    def email_receipts(self, request: HttpRequest, queryset):
         qs = queryset.filter(status="PAID")
         count = qs.count()
 
@@ -279,15 +279,15 @@ def email_receipts(self, request, queryset):
             return
 
         for obj in queryset:
-            obj.email_receipt()
+            obj.email_receipt(request)
         self.message_user(
             request,
             f"{count} receipt(s) sent",
             messages.SUCCESS,
         )
 
     @admin.action(description="Download completed payment receipts")
-    def download_receipts(self, request, queryset):
+    def download_receipts(self, request: HttpRequest, queryset: QuerySet):
         qs = queryset.filter(status="PAID")
 
         if not qs.count():

dds_registration/core/helpers/create_pdf.py

@@ -32,7 +32,7 @@
 
 
 def normalize_text(text: str) -> str:
-    return text.encode('utf-8', 'ignore').decode('utf-8').strip()
+    return text.encode("utf-8", "ignore").decode("utf-8").strip()
 
 
 def create_pdf(
@@ -87,11 +87,18 @@ def create_pdf(
 
     # Left (client) address column...
     pdf.set_xy(left_column_pos, margin_size + top_offset)
-    pdf.multi_cell(text=normalize_text(client_name), w=left_column_width, align=Align.L, new_x="LEFT", new_y="NEXT", h=line_height)
+    pdf.multi_cell(
+        text=normalize_text(client_name), w=left_column_width, align=Align.L, new_x="LEFT", new_y="NEXT", h=line_height
+    )
 
     pdf.set_y(pdf.get_y() + small_vertical_space)
     pdf.multi_cell(
-        text=normalize_text(client_address), w=left_column_width, align=Align.L, new_x="LEFT", new_y="NEXT", h=line_height
+        text=normalize_text(client_address),
+        w=left_column_width,
+        align=Align.L,
+        new_x="LEFT",
+        new_y="NEXT",
+        h=line_height,
     )
 
     left_stop_pos = pdf.get_y()

dds_registration/core/helpers/emails.py

@@ -0,0 +1,31 @@
+import re
+
+
+def prepare_email_message_text(text: str) -> str:
+    # Remove spaces around
+    text = text.strip()
+    # Remove spaces before newlines
+    text = re.sub(r"[ \t]*[\n\r]", "\n", text)
+    # Leave max two newlines in a row
+    text = re.sub(r"\n{3,}", "\n\n", text)
+    return text
+
+
+def parse_email_subject_and_content(text: str) -> list[str]:
+    """
+    Email message should contain a subject in the beginning, separated from the content by double newline.
+    Returns the list consisted of [subject, content]
+    """
+    text = prepare_email_message_text(text)
+    results = text.split("\n\n", 1)
+    if len(results) < 2:
+        raise Exception(
+            "Email message should constist of a subject and a content, separated from the content by double newline."
+        )
+    return results
+
+
+__all__ = [
+    prepare_email_message_text,
+    parse_email_subject_and_content,
+]

dds_registration/models.py

@@ -4,20 +4,25 @@
 import random
 import string
 from datetime import date
-
 import requests
+
+from fpdf import FPDF
+
+from django.contrib.sites.models import Site
+from django.http import HttpRequest
 from django.conf import settings
 from django.contrib.auth.models import AbstractUser
 from django.core.exceptions import ObjectDoesNotExist
 from django.db import models
 from django.db.models import Model, Q, QuerySet
 from django.urls import reverse
-from fpdf import FPDF
+from django.template.loader import render_to_string
 
 from dds_registration.core.constants.payments import (
     site_default_currency,
     site_supported_currencies,
 )
+from .core.helpers.emails import parse_email_subject_and_content
 
 from .core.constants.date_time_formats import dateFormat
 from .core.constants.payments import currency_emojis, payment_details_by_currency
@@ -220,7 +225,7 @@ def mark_obsolete(self):
         )
         self.save()
 
-    def mark_paid(self):
+    def mark_paid(self, request: HttpRequest):
         if self.status == "PAID":
             return
         self.status = "PAID"
@@ -235,7 +240,7 @@ def mark_paid(self):
                     )
                 },
             )
-        self.email_receipt()
+        self.email_receipt(request)
         self.save()
 
     @property
@@ -285,29 +290,55 @@ def invoice_pdf(self):
     def receipt_pdf(self):
         return create_receipt_pdf_from_payment(self)
 
-    def email_invoice(self):
+    def email_invoice(self, request: HttpRequest):
         user = User.objects.get(id=self.data["user"]["id"])
-        # TODO: Issue #149: To extract these (and all other hardcoded here, in `send_email` methods?) texts to template files, with substiting names, urls and emails from settings or preferences values?
+        context = {
+            "site": Site.objects.get_current(),
+            "scheme": "https" if request.is_secure() else "http",
+            "payment": self,
+            "user": user,
+        }
         if self.data["kind"] == "membership":
-            subject = f"DdS Membership Invoice {self.invoice_no}"
-            message = f"Thanks for signing up for Départ de Sentier membership! Membership fees allow us to write awesome open source code, deploy open infrastructure, and run community events without spending all our time fundraising.\n\nYour membership will run until December 31st, {user.membership.until} (Don't worry, you will get a reminder to renew for another year :).\n\nPlease find attached the membership invoice. Your membership is not in force until the bank transfer is received.\n\nYou can change your invoice details here: https://events.d-d-s.ch{reverse('membership_application')}.\n\nIf you have any questions, please contact [email protected]."
+            email_template = "dds_registration/payment/emails/invoice_membership.txt.django"
         else:
-            event = Event.objects.get(id=self.data["event"]["id"])
-            subject = f"DdS Event {event.title} Registration Invoice {self.invoice_no}"
-            message = f"Thanks for registering for {event.title}! We look forward to seeing your, in person or virtually.\n\nDépart de Sentier runs its events and schools on a cost-neutral basis - i.e. we don't make a profit off the registration fees. They are used for catering, room, hotel, and equipment rental, AV hosting and technician fees, and guest speaker costs. We literally could not run this event without your support.\n\nYou can view your registration status and apply for membership at https://events.d-d-s.ch/profile.\n\nPlease find attached the registration invoice. Your registration is not finalized until the bank transfer is received.\n\nYou can change your invoice details here: https://events.d-d-s.ch{reverse('event_registration', args=(event.code,))}.\n\nIf you have any questions, please contact [email protected]."
+            context["event"] = Event.objects.get(id=self.data["event"]["id"])
+            email_template = "dds_registration/payment/emails/invoice_membership.txt.django"
+        # Parse email message template
+        text = render_to_string(
+            template_name=email_template,
+            context=context,
+            request=request,
+        )
+        # Extract a subject and a message from the template
+        [subject, message] = parse_email_subject_and_content(text)
         user.email_user(
             subject=subject,
             message=message,
             attachment_content=self.invoice_pdf(),
             attachment_name=f"DdS Invoice {self.invoice_no}.pdf",
         )
 
-    def email_receipt(self):
+    def email_receipt(self, request: HttpRequest):
         user = User.objects.get(id=self.data["user"]["id"])
-        kind = "Membership" if self.data["kind"] == "membership" else "Event"
+        context = {
+            "kind": "Membership" if self.data["kind"] == "membership" else "Event",
+            "site": Site.objects.get_current(),
+            "scheme": "https" if request.is_secure() else "http",
+            "payment": self,
+            "user": user,
+        }
+        email_template = "dds_registration/payment/emails/receipt.txt.django"
+        # Parse email message template
+        text = render_to_string(
+            template_name=email_template,
+            context=context,
+            request=request,
+        )
+        # Extract a subject and a message from the template
+        [subject, message] = parse_email_subject_and_content(text)
         user.email_user(
-            subject=f"DdS {kind} Receipt {self.invoice_no}",
-            message="Thanks! A receipt for your event or membership payment is attached. You can always find more information about your item at your your profile: https://events.d-d-s.ch/profile.\n\nWe really appreciate your support. If you have any questions, please contact [email protected].",
+            subject=subject,
+            message=message,
             attachment_content=self.receipt_pdf(),
             attachment_name=f"DdS receipt {self.invoice_no}.pdf",
         )

dds_registration/templates/dds_registration/event/event_payment_receipt_message_body.txt

@@ -9,7 +9,7 @@ You have registered and already paid for {{ event.title }}!
 
 {% endif %}The payment option you have chosen: {% with option=registration.option %}{{ option.item }}{% if option.price %} ({% if option.currency %}{{ option.currency }} {% endif %}{{ option.price }}){% endif %}{% endwith %}.
 
-{% endcomment %}Your invoice is attached, but can also be download anytime at {{ scheme }}://{{site.domain}}{% url 'billing_event_invoice_download' event_code=event.code %}.
+{% endcomment %}Your invoice is attached, but can also be download anytime at {{ scheme }}://{{ site.domain }}{% url 'billing_event_invoice_download' event_code=event.code %}.
 
 If you have questions or comments, you can reach us at {{ settings.DEFAULT_FROM_EMAIL }}.
 

dds_registration/templates/dds_registration/payment/emails/invoice_event.txt.django

@@ -0,0 +1,15 @@
+DdS Event {{ event.title }} Registration Invoice {{ payment.invoice_no }}
+
+
+Thanks for registering for {{ event.title }}! We look forward to seeing your, in person or virtually.
+
+Départ de Sentier runs its events and schools on a cost-neutral basis - i.e. we don't make a profit off the registration fees. They are used for catering, room, hotel, and equipment rental, AV hosting and technician fees, and guest speaker costs. We literally could not run this event without your support.
+
+You can view your registration status and apply for membership at {{ scheme }}://{{ site.domain }}{% url 'profile' %}.
+
+Please find attached the registration invoice. Your registration is not finalized until the bank transfer is received.
+
+You can change your invoice details here: {{ scheme }}://{{ site.domain }}{% url 'event_registration' event_code=event.code %}.
+
+If you have any questions, please contact {{ settings.DEFAULT_CONTACT_EMAIL }}.
+

dds_registration/templates/dds_registration/payment/emails/invoice_membership.txt.django

@@ -0,0 +1,14 @@
+DdS Membership Invoice {{ payment.invoice_no }}
+
+
+Thanks for signing up for Départ de Sentier membership!
+
+Membership fees allow us to write awesome open source code, deploy open infrastructure, and run community events without spending all our time fundraising.
+
+Your membership will run until December 31st, {{ user.membership.until }} (Don't worry, you will get a reminder to renew for another year :).
+
+Please find attached the membership invoice. Your membership is not in force until the bank transfer is received.
+
+You can change your invoice details here: {{ scheme }}://{{ site.domain }}{% url 'membership_application' %}.
+
+If you have any questions, please contact {{ settings.DEFAULT_CONTACT_EMAIL }}.

dds_registration/templates/dds_registration/payment/emails/receipt.txt.django

@@ -0,0 +1,12 @@
+DdS {{ kind }} Receipt {{ payment.invoice_no }}
+
+
+Thanks!
+
+A receipt for your event or membership payment is attached.
+
+You can always find more information about your item at your your profile: {{ scheme }}://{{ site.domain }}{% url 'profile' %}.
+
+We really appreciate your support.
+
+If you have any questions, please contact {{ settings.DEFAULT_CONTACT_EMAIL }}.

dds_registration/urls/payments_urls.py

@@ -1,6 +1,6 @@
 from django.urls import path
 
-from ..views.billing_stripe import payment_stripe, payment_stripe_success
+from ..views.payment_stripe import payment_stripe, payment_stripe_success
 from ..views.payment_utils import invoice_download, receipt_download
 
 urlpatterns = [

dds_registration/views/event_registration.py

@@ -101,7 +101,7 @@ def event_registration(request: HttpRequest, event_code: str):
             registration.save()
 
             if payment.data["method"] == "INVOICE":
-                payment.email_invoice()
+                payment.email_invoice(request)
                 payment.status = "ISSUED"
                 payment.save()
                 messages.success(

dds_registration/views/helpers/stripe_amounts.py

@@ -1,9 +1,13 @@
+from ...core.constants.payments import site_supported_currencies
+
+
 def get_stripe_amount_for_currency(amount: int, currency: str, convert_basic_unit: bool = True) -> int:
     """Stripe fees vary by country.
 
     Note: Assumes amount in stripe basic unit!!!"""
     if convert_basic_unit:
         amount = get_stripe_basic_unit(amount=amount, currency=currency)
+    # NOTE: Must match the list of currencies in `site_supported_currencies`
     if currency == "USD":
         # Stripe fee is 2.9%, currency conversion loss is 1%
         return round(30 + (1 + 0.029 + 0.01) * amount)
@@ -24,14 +28,16 @@ def get_stripe_basic_unit(amount: float, currency: str) -> int:
     """Stripe wants numbers in lower divisible unit.
 
     This varies by country."""
-    if currency in ("CAD", "CHF", "EUR", "CAD"):
+    currency_ids = dict(site_supported_currencies).keys()
+    if currency in currency_ids:
         return round(amount * 100)
     else:
         raise ValueError(f"Unrecognized currency {currency}")
 
 
 def convert_from_stripe_units(amount: float, currency: str) -> float:
-    if currency in ("CAD", "CHF", "EUR", "CAD"):
+    currency_ids = dict(site_supported_currencies).keys()
+    if currency in currency_ids:
         return round(amount / 100, 2)
     else:
         raise ValueError(f"Unrecognized currency {currency}")

dds_registration/views/membership.py

@@ -69,7 +69,7 @@ def membership_application(request: HttpRequest):
             if payment.data["method"] == "INVOICE":
                 payment.status = "ISSUED"
                 payment.save()
-                payment.email_invoice()
+                payment.email_invoice(request)
                 messages.success(
                     request,
                     f"Your membership has been created! An invoice has been sent to {request.user.email} from [email protected]. The invoice can also be downloaded from your profile. Please note your membership is not in force until the invoice is paid.",

dds_registration/views/billing_stripe.py → dds_registration/views/payment_stripe.py

@@ -42,7 +42,7 @@ def payment_stripe(request: HttpRequest, payment_id: int):
         payment.data["currency"], stripe_amount, request.user.email, {"payment_id": payment.id}
     )
 
-    template = "dds_registration/billing/stripe_payment.html.django"
+    template = "dds_registration/payment/stripe_payment.html.django"
 
     try:
         membership = Membership.objects.get(user=request.user)
@@ -78,7 +78,7 @@ def payment_stripe_success(request: HttpRequest, payment_id: int):
         return redirect("profile")
 
     payment.data["price"] = payment.data.pop("stripe_charge_in_progress")
-    payment.mark_paid()
+    payment.mark_paid(request)
 
     if payment.data["kind"] == "membership":
         messages.success(request, "Awesome, your membership is paid, and you are good to go!")