Introduce subscription periods.

Makefile

@@ -1,4 +1,4 @@
-DOCKER_COMPOSE = COMPOSE_DOCKER_CLI_BUILD=1 DOCKER_BUILDKIT=1 docker-compose
+DOCKER_COMPOSE = COMPOSE_DOCKER_CLI_BUILD=1 DOCKER_BUILDKIT=1 venv/bin/docker-compose
 DOCKER_RUN = ${DOCKER_COMPOSE} run -u `id -u`
 DOCKER_BUILD = DOCKER_BUILDKIT=1 docker build
 DOCKER_CONTAINER_NAME = backend

requirements/base.in

@@ -1,4 +1,4 @@
-Django==4.1
+Django==4.1.5
 django-money==1.3
 django-allauth==0.46
 psycopg2-binary==2.9.5

src/membership/admin.py

@@ -2,6 +2,7 @@ from django.contrib import admin
 
 from .models import Membership
 from .models import MembershipType
+from .models import SubscriptionPeriod
 
 
 @admin.register(Membership)
@@ -12,3 +13,8 @@ class MembershipAdmin(admin.ModelAdmin):
 @admin.register(MembershipType)
 class MembershipTypeAdmin(admin.ModelAdmin):
     pass
+
+
+@admin.register(SubscriptionPeriod)
+class SubscriptionPeriodAdmin(admin.ModelAdmin):
+    pass

src/membership/migrations/0002_subscriptionperiod_remove_membership_period_and_more.py

@@ -0,0 +1,63 @@
+# Generated by Django 4.1 on 2023-01-02 21:05
+
+import django.contrib.postgres.constraints
+import django.contrib.postgres.fields.ranges
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("membership", "0001_initial"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="SubscriptionPeriod",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "modified",
+                    models.DateTimeField(auto_now=True, verbose_name="modified"),
+                ),
+                (
+                    "created",
+                    models.DateTimeField(auto_now_add=True, verbose_name="created"),
+                ),
+                (
+                    "period",
+                    django.contrib.postgres.fields.ranges.DateRangeField(
+                        verbose_name="period"
+                    ),
+                ),
+            ],
+        ),
+        migrations.RemoveField(
+            model_name="membership",
+            name="period",
+        ),
+        migrations.AlterField(
+            model_name="membership",
+            name="created",
+            field=models.DateTimeField(auto_now_add=True, verbose_name="created"),
+        ),
+        migrations.AlterField(
+            model_name="membershiptype",
+            name="created",
+            field=models.DateTimeField(auto_now_add=True, verbose_name="created"),
+        ),
+        migrations.AddConstraint(
+            model_name="subscriptionperiod",
+            constraint=django.contrib.postgres.constraints.ExclusionConstraint(
+                expressions=[("period", "&&")], name="exclude_overlapping_periods"
+            ),
+        ),
+    ]

src/membership/migrations/0003_membership_period.py

@@ -0,0 +1,23 @@
+# Generated by Django 4.1 on 2023-01-02 21:05
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("membership", "0002_subscriptionperiod_remove_membership_period_and_more"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="membership",
+            name="period",
+            field=models.ForeignKey(
+                null=True,
+                on_delete=django.db.models.deletion.PROTECT,
+                to="membership.subscriptionperiod",
+            ),
+        ),
+    ]

src/membership/migrations/0004_alter_membership_period.py

@@ -0,0 +1,22 @@
+# Generated by Django 4.1 on 2023-01-02 21:06
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("membership", "0003_membership_period"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="membership",
+            name="period",
+            field=models.ForeignKey(
+                on_delete=django.db.models.deletion.PROTECT,
+                to="membership.subscriptionperiod",
+            ),
+        ),
+    ]

src/membership/models.py

@@ -1,18 +1,31 @@
 from typing import Optional
 
-from django.contrib.postgres.fields import DateTimeRangeField
+from django.contrib.postgres.constraints import ExclusionConstraint
+from django.contrib.postgres.fields import DateRangeField
+from django.contrib.postgres.fields import RangeOperators
 from django.db import models
 from django.utils import timezone
 from django.utils.translation import gettext as _
 
+from utils.mixins import CreatedModifiedAbstract
 
-class CreatedModifiedAbstract(models.Model):
 
-    modified = models.DateTimeField(auto_now=True, verbose_name=_("modified"))
-    created = models.DateTimeField(auto_now_add=True, verbose_name=_("created"))
+class SubscriptionPeriod(CreatedModifiedAbstract):
+    """
+    Denotes a period for which members should pay their membership fee for.
+    """
+
+    period = DateRangeField(verbose_name=_("period"))
 
     class Meta:
-        abstract = True
+        constraints = [
+            ExclusionConstraint(
+                name="exclude_overlapping_periods",
+                expressions=[
+                    ("period", RangeOperators.OVERLAPS),
+                ],
+            ),
+        ]
 
 
 class Membership(CreatedModifiedAbstract):
@@ -25,7 +38,7 @@ class Membership(CreatedModifiedAbstract):
             return self.filter(user=user)
 
         def _current(self):
-            return self.filter(period__contains=timezone.now())
+            return self.filter(period__period__contains=timezone.now())
 
         def current(self) -> Optional["Membership"]:
             try:
@@ -54,7 +67,9 @@ class Membership(CreatedModifiedAbstract):
         on_delete=models.PROTECT,
     )
 
-    period = DateTimeRangeField(help_text=_("The duration this subscription is for. "))
+    period = models.ForeignKey(
+        "membership.SubscriptionPeriod", on_delete=models.PROTECT
+    )
 
     def __str__(self):
         return f"{self.user} - {self.period}"

src/membership/templates/membership_overview.html

@@ -16,7 +16,8 @@
     {% else %}
         <p>{% trans "You are a member!" %}</p>
 
-        <p>{% trans "Period" %}: {{ current_membership.period.lower|date:"SHORT_DATE_FORMAT" }} to {{ current_membership.period.upper|date:"SHORT_DATE_FORMAT" }}</p>
+        {% trans "next general assembly" as next_general_assembly %}
+        <p>{% trans "Period" %}: {{ current_period.lower|date:"SHORT_DATE_FORMAT" }} to {{ current_period.upper|date:"SHORT_DATE_FORMAT"|default:next_general_assembly }}</p>
         <p>{% trans "Type" %}: {{ current_membership.membership_type }}</p>
     {% endif %}
     {% endblock %}

src/membership/views.py

@@ -10,9 +10,16 @@ def membership_overview(request):
     current_membership = memberships.current()
     previous_memberships = memberships.previous()
 
+    current_period = current_membership.period.period if current_membership else None
+
     context = {
         "current_membership": current_membership,
+        "current_period": current_period,
         "previous_memberships": previous_memberships,
     }
 
-    return render(request, "membership_overview.html", context)
+    return render(
+        request=request,
+        template_name="membership_overview.html",
+        context=context,
+    )

src/utils/mixins.py

@@ -0,0 +1,11 @@
+from django.db import models
+from django.utils.translation import gettext_lazy as _
+
+
+class CreatedModifiedAbstract(models.Model):
+
+    modified = models.DateTimeField(auto_now=True, verbose_name=_("modified"))
+    created = models.DateTimeField(auto_now_add=True, verbose_name=_("created"))
+
+    class Meta:
+        abstract = True