send mail to inactive users

counter/admin.py

@@ -49,6 +49,18 @@ class BillingInfoAdmin(admin.ModelAdmin):
     autocomplete_fields = ("customer",)
 
 
+@admin.register(AccountDump)
+class AccountDumpAdmin(admin.ModelAdmin):
+    list_display = (
+        "customer",
+        "warning_mail_sent_at",
+        "warning_mail_error",
+        "dump_operation",
+    )
+    autocomplete_fields = ("customer",)
+    list_filter = ("warning_mail_error",)
+
+
 @admin.register(Counter)
 class CounterAdmin(admin.ModelAdmin):
     list_display = ("name", "club", "type")

counter/management/commands/dump_warning_mail.py

@@ -0,0 +1,88 @@
+import logging
+from smtplib import SMTPException
+
+from django.conf import settings
+from django.core.mail import send_mail
+from django.core.management.base import BaseCommand
+from django.db.models import Exists, OuterRef, Subquery
+from django.template.loader import render_to_string
+from django.utils.timezone import localdate, now
+from django.utils.translation import gettext as _
+
+from core.models import User
+from counter.models import AccountDump
+from subscription.models import Subscription
+
+
+class Command(BaseCommand):
+    """Send mail to inactive users, warning them that their account is about to be dumped.
+
+    This command should be automated with a cron task.
+    """
+
+    def __init__(self, *args, **kwargs):
+        self.logger = logging.getLogger("account_dump_mail")
+        self.logger.setLevel(logging.INFO)
+        super().__init__(*args, **kwargs)
+
+    def handle(self, *args, **options):
+        ongoing_dump_operation = AccountDump.objects.ongoing().filter(
+            customer__user=OuterRef("pk")
+        )
+        users = list(
+            User.objects
+            .filter_inactive()
+            .filter(customer__amount__gt=0)
+            .exclude(Exists(ongoing_dump_operation))
+            .annotate(
+                last_subscription_date=Subquery(
+                    Subscription.objects.filter(member=OuterRef("pk"))
+                    .order_by("-subscription_end")
+                    .values("subscription_end")[:1]
+                ),
+            )
+            .select_related("customer")
+        )
+        self.stdout.write(f"{len(users)} users will be warned of their account dump")
+        dumps = []
+        for user in users:
+            is_success = self._send_mail(user)
+            dumps.append(
+                AccountDump(
+                    customer_id=user.id,
+                    warning_mail_sent_at=now(),
+                    warning_mail_error=not is_success,
+                )
+            )
+        AccountDump.objects.bulk_create(dumps)
+        self.stdout.write("Finished !")
+
+    def _send_mail(self, user: User) -> bool:
+        """Send the warning email to the given user.
+
+        Returns:
+            True if the mail was successfully sent, else False
+        """
+        message = render_to_string(
+            "counter/account_dump_warning_mail.jinja",
+            {
+                "balance": user.customer.amount,
+                "last_subscription_date": user.last_subscription_date,
+                "dump_date": localdate() + settings.SITH_ACCOUNT_DUMP_DELTA,
+            },
+        )
+        try:
+            # sending mails one by one is long and ineffective,
+            # but it makes easier to know which emails failed (and how).
+            # Also, there won't be that much mails sent (except on the first run)
+            send_mail(
+                _("Clearing of your AE account"),
+                message,
+                settings.DEFAULT_FROM_EMAIL,
+                [user.email],
+            )
+            self.logger.info(f"Mail successfully sent to {user.email}")
+            return True
+        except SMTPException as e:
+            self.logger.error(f"failed mail to {user.email} :\n{e}")
+            return False

counter/migrations/0024_accountdump_accountdump_unique_ongoing_dump.py

@@ -0,0 +1,64 @@
+# Generated by Django 4.2.16 on 2024-10-06 14:33
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [("counter", "0023_billinginfo_phone_number")]
+
+    operations = [
+        migrations.CreateModel(
+            name="AccountDump",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "warning_mail_sent_at",
+                    models.DateTimeField(
+                        help_text="When the mail warning that the account was about to be dumped was sent."
+                    ),
+                ),
+                (
+                    "warning_mail_error",
+                    models.BooleanField(
+                        default=False,
+                        help_text="Set this to True if the warning mail received an error",
+                    ),
+                ),
+                (
+                    "customer",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="dumps",
+                        to="counter.customer",
+                    ),
+                ),
+                (
+                    "dump_operation",
+                    models.OneToOneField(
+                        blank=True,
+                        help_text="The operation that emptied the account.",
+                        null=True,
+                        on_delete=django.db.models.deletion.CASCADE,
+                        to="counter.selling",
+                    ),
+                ),
+            ],
+        ),
+        migrations.AddConstraint(
+            model_name="accountdump",
+            constraint=models.UniqueConstraint(
+                condition=models.Q(("dump_operation", None)),
+                fields=("customer",),
+                name="unique_ongoing_dump",
+            ),
+        ),
+    ]

counter/models.py

@@ -26,7 +26,7 @@ from dict2xml import dict2xml
 from django.conf import settings
 from django.core.validators import MinLengthValidator
 from django.db import models
-from django.db.models import Exists, F, OuterRef, QuerySet, Sum, Value
+from django.db.models import Exists, F, OuterRef, Q, QuerySet, Sum, Value
 from django.db.models.functions import Concat, Length
 from django.forms import ValidationError
 from django.urls import reverse
@@ -211,6 +211,51 @@ class BillingInfo(models.Model):
         return '<?xml version="1.0" encoding="UTF-8" ?>' + xml
 
 
+class AccountDumpQuerySet(models.QuerySet):
+    def ongoing(self) -> Self:
+        """Filter dump operations that are not completed yet."""
+        return self.filter(dump_operation=None)
+
+
+class AccountDump(models.Model):
+    """The process of dumping an account."""
+
+    customer = models.ForeignKey(
+        Customer, related_name="dumps", on_delete=models.CASCADE
+    )
+    warning_mail_sent_at = models.DateTimeField(
+        help_text=_(
+            "When the mail warning that the account was about to be dumped was sent."
+        )
+    )
+    warning_mail_error = models.BooleanField(
+        default=False,
+        help_text=_("Set this to True if the warning mail received an error"),
+    )
+    dump_operation = models.OneToOneField(
+        "Selling",
+        null=True,
+        blank=True,
+        on_delete=models.CASCADE,
+        help_text=_("The operation that emptied the account."),
+    )
+
+    objects = AccountDumpQuerySet.as_manager()
+
+    class Meta:
+        constraints = [
+            models.UniqueConstraint(
+                fields=["customer"],
+                condition=Q(dump_operation=None),
+                name="unique_ongoing_dump",
+            ),
+        ]
+
+    def __str__(self):
+        status = "ongoing" if self.dump_operation is None else "finished"
+        return f"{self.customer} - {status}"
+
+
 class ProductType(models.Model):
     """A product type.
 

counter/templates/counter/account_dump_warning_mail.jinja

@@ -0,0 +1,43 @@
+<p>
+  Bonjour,
+</p>
+
+<p>
+  {% trans date=last_subscription_date|date(DATETIME_FORMAT) %}
+    You received this email because your last subscription to the
+    Students' association ended on {{ date }}.
+  {% endtrans %}
+</p>
+
+<p>
+  {% trans date=dump_date|date(DATETIME_FORMAT) %}
+    In accordance with the Internal Regulations, the balance of any
+    inactive AE account for more than 2 years automatically goes back
+    to the AE.
+    The money present on your account will therefore be recovered in full
+    on {{ date }}.
+  {% endtrans %}
+</p>
+
+<p>
+  {% trans %}However, if your subscription is renewed by this date,
+    your right to keep the money in your AE account will be renewed.{% endtrans %}
+</p>
+
+{% if balance >= 10 %}
+  <p>
+    {% trans %}You can also request a refund by sending an email to
+      <a href="mailto:ae@utbm.fr">ae@utbm.fr</a>
+      before the aforementioned date.{% endtrans %}
+  </p>
+{% endif %}
+
+<p>
+  {% trans %}Sincerely{% endtrans %},
+</p>
+
+<p>
+  L'association des étudiants de l'UTBM <br>
+  6, Boulevard Anatole France <br>
+  90000 Belfort
+</p>

counter/tests/test_account_dump.py

@@ -0,0 +1,7 @@
+import pytest
+
+
+@pytest.mark.django_db
+def test_account_dump():
+    # TODO write the fucking test
+    pass

sith/settings.py

@@ -37,6 +37,7 @@ import binascii
 import logging
 import os
 import sys
+from datetime import timedelta
 from pathlib import Path
 
 import sentry_sdk
@@ -229,13 +230,20 @@ LOGGING = {
             "class": "logging.StreamHandler",
             "formatter": "simple",
         },
+        "dump_mail_file": {
+            "level": "DEBUG",
+            "class": "logging.FileHandler",
+            "filename": "account_dump_mail.log",
+            "formatter": "simple",
+        },
     },
     "loggers": {
         "main": {
             "handlers": ["log_to_stdout"],
             "level": "INFO",
             "propagate": True,
-        }
+        },
+        "account_dump_mail": {"handlers": ["dump_mail_file", "log_to_stdout"]},
     },
 }
 
@@ -498,6 +506,8 @@ SITH_COUNTER_CASH_SUMMARY_LENGTH = 50
 
 SITH_ACCOUNT_INACTIVITY_DELTA = relativedelta(years=2)
 """Time before which a user account is considered inactive"""
+SITH_ACCOUNT_DUMP_DELTA = timedelta(days=30)
+"""timedelta between the warning mail and the actual account dump"""
 
 # Defines which product type is the refilling type, and thus increases the account amount
 SITH_COUNTER_PRODUCTTYPE_REFILLING = 3