feat: send invoice generated notification email and payments receipt mail

billing/templates/billing/emails/payment-notification.txt

@@ -0,0 +1,14 @@
+Hello {{ username }}!
+
+An invoice is generated for your Hostea VM {{ payment.instance_name }}.
+
+- Configuration: {{payment.instance_configuration_id.name}}
+- Invoice generated on: {{payment.date.month}}/{{payment.date.day}}/{{payment.date.year}}
+- Total Amount: {{payment.total}} {{payment.currency|upper}}
+
+To pay, please click the link below:
+
+{{ link }}
+
+Cheers,
+Hostea team

billing/templates/billing/emails/payment-receipt.txt

@@ -0,0 +1,22 @@
+Hello {{ username }}!
+
+
+This is a receipt for your latest Hostea payment.
+
+-----------------------------------------------------
+
+Hostea Receipt - {{payment.date.month}}/{{payment.date.day}}/{{payment.date.year}}
+
+- Instance Name: {{ payment.instance_name }}
+- Configuration: {{payment.instance_configuration_id.name}}
+- Total Amount: {{payment.total}} {{payment.currency|upper}}
+
+
+To view the receipt online, please see the following link: 
+
+{% url 'billing.invoice.details' payment_public_id=payment.public_ref %}
+
+We appreciate your business!
+
+Cheers,
+Hostea team

billing/tests.py

@@ -16,6 +16,7 @@ import time
 from io import StringIO
 
 from django.contrib.auth import get_user_model
+from django.core import mail
 from django.core.management import call_command
 from django.urls import reverse
 from django.test import TestCase, Client, override_settings
@@ -89,6 +90,47 @@ class BillingTest(TestCase):
             reverse("infra.create", args=(payment.instance_name,)),
         )
 
+        # create_instance_util creates an instance and pays for it. An email is
+        # sent when the invoice is generated and one after payment is made
+        #
+        # So we are first checking for the last email that was sent(receipt)
+        # and then the Gitea instance credentials notification followed by the
+        # invoice generation email.
+        receipt_mail = mail.outbox.pop()
+        self.assertEqual(
+            all(
+                [
+                    receipt_mail.to[0] == self.email,
+                    "This is a receipt for your latest Hostea payment"
+                    in receipt_mail.body,
+                ]
+            ),
+            True,
+        )
+
+        instance_notificaiton = mail.outbox.pop()
+        self.assertEqual(
+            all(
+                [
+                    instance_notificaiton.to[0] == self.email,
+                    "Congratulations on your new Gitea instance!"
+                    in instance_notificaiton.body,
+                ]
+            ),
+            True,
+        )
+
+        invoice_generated_mail = mail.outbox.pop()
+        self.assertEqual(
+            all(
+                [
+                    invoice_generated_mail.to[0] == self.email,
+                    "An invoice is generated" in invoice_generated_mail.body,
+                ]
+            ),
+            True,
+        )
+
         ## payment failure page; no real functionality but user is redirected here
         # by stripe if payment is successful
         resp = c.get(reverse("billing.invoice.fail", args=(payment.public_ref,)))

billing/views.py

@@ -16,13 +16,16 @@ from datetime import datetime, timedelta, timezone
 
 from django.shortcuts import get_object_or_404, redirect, render
 from django.template.response import TemplateResponse
+from django.core.mail import send_mail
 from django.contrib.auth.decorators import login_required
 from django.http import HttpResponse
+from django.template.loader import render_to_string
 from django.urls import reverse
+from django.db.models import Q
+from django.conf import settings
 
 from payments import get_payment_model, RedirectNeeded, PaymentStatus
 from dash.models import Instance
-from django.db.models import Q
 from infrastructure.utils import create_vm_if_not_exists
 from dash.utils import footer_ctx
 
@@ -88,7 +91,29 @@ def generate_invoice(request, instance_name: str):
             instance=instance,
         )
 
-    return redirect(reverse("billing.invoice.details", args=(payment.public_ref,)))
+        invoice_link = reverse("billing.invoice.details", args=(payment.public_ref,))
+        ctx = {
+            "username": request.user.username,
+            "link": invoice_link,
+            "payment": payment,
+        }
+
+        body = render_to_string(
+            "billing/emails/payment-notification.txt",
+            context=ctx,
+        )
+
+        email = request.user.email
+        sender = settings.DEFAULT_FROM_EMAIL
+
+        send_mail(
+            subject="[Hostea] An invoice is generated for your Hostea VM",
+            message=body,
+            from_email=f"No reply Hostea<{sender}>",  # TODO read from settings.py
+            recipient_list=[email],
+        )
+
+        return redirect(invoice_link)
 
 
 @login_required
@@ -118,6 +143,26 @@ def payment_success(request, payment_public_id):
     payment = get_object_or_404(
         get_payment_model(), public_ref=payment_public_id, paid_by=request.user
     )
+    ctx = {
+        "username": request.user.username,
+        "payment": payment,
+    }
+
+    body = render_to_string(
+        "billing/emails/payment-receipt.txt",
+        context=ctx,
+    )
+
+    email = request.user.email
+    sender = settings.DEFAULT_FROM_EMAIL
+
+    send_mail(
+        subject="[Hostea] Payment receipt your Hostea VM",
+        message=body,
+        from_email=f"No reply Hostea<{sender}>",  # TODO read from settings.py
+        recipient_list=[email],
+    )
+
     return redirect(reverse("infra.create", args=(payment.instance_name,)))