Add payment plan switching

memberportal/api_billing/admin.py

@@ -0,0 +1,42 @@
+from django.contrib import admin
+
+from .models import PaymentPlanSwitchOperation
+
+
+@admin.register(PaymentPlanSwitchOperation)
+class PaymentPlanSwitchOperationAdmin(admin.ModelAdmin):
+    list_display = (
+        "profile",
+        "current_plan",
+        "target_plan",
+        "status",
+        "attempt_count",
+        "updated_at",
+    )
+    list_filter = ("status",)
+    search_fields = (
+        "profile__user__email",
+        "stripe_subscription_id",
+        "idempotency_key",
+    )
+    readonly_fields = (
+        "profile",
+        "current_plan",
+        "target_plan",
+        "stripe_subscription_id",
+        "idempotency_key",
+        "status",
+        "attempt_count",
+        "last_error",
+        "created_at",
+        "updated_at",
+    )
+
+    @admin.action(description="Discard selected failed plan switches")
+    def discard_failed_operations(self, request, queryset):
+        queryset.filter(status=PaymentPlanSwitchOperation.STATUS_FAILED).delete()
+
+    actions = ("discard_failed_operations",)
+
+    def has_delete_permission(self, request, obj=None):
+        return obj is None or obj.status == PaymentPlanSwitchOperation.STATUS_FAILED

memberportal/api_billing/migrations/0002_paymentplanswitchoperation.py

@@ -0,0 +1,74 @@
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("api_admin_tools", "0013_paymentplan_description"),
+        ("api_billing", "0001_initial"),
+        ("constance", "0003_drop_pickle"),
+        ("profile", "0033_alter_inductionproviderstate_provider"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="PaymentPlanSwitchOperation",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("stripe_subscription_id", models.CharField(max_length=100)),
+                ("idempotency_key", models.CharField(max_length=255, unique=True)),
+                (
+                    "status",
+                    models.CharField(
+                        choices=[("pending", "Pending")],
+                        default="pending",
+                        max_length=16,
+                    ),
+                ),
+                ("attempt_count", models.PositiveIntegerField(default=0)),
+                ("last_error", models.TextField(blank=True, default="")),
+                ("created_at", models.DateTimeField(auto_now_add=True)),
+                ("updated_at", models.DateTimeField(auto_now=True)),
+                (
+                    "current_plan",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.PROTECT,
+                        related_name="switch_operations_from",
+                        to="api_admin_tools.paymentplan",
+                    ),
+                ),
+                (
+                    "profile",
+                    models.OneToOneField(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="payment_plan_switch_operation",
+                        to="profile.profile",
+                    ),
+                ),
+                (
+                    "target_plan",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.PROTECT,
+                        related_name="switch_operations_to",
+                        to="api_admin_tools.paymentplan",
+                    ),
+                ),
+            ],
+            options={
+                "indexes": [
+                    models.Index(
+                        fields=["status", "updated_at"],
+                        name="api_billing_status_55ab81_idx",
+                    )
+                ],
+            },
+        ),
+    ]

memberportal/api_billing/migrations/0003_paymentplanswitchoperation_failed.py

@@ -0,0 +1,19 @@
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("api_billing", "0002_paymentplanswitchoperation"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="paymentplanswitchoperation",
+            name="status",
+            field=models.CharField(
+                choices=[("pending", "Pending"), ("failed", "Failed")],
+                default="pending",
+                max_length=16,
+            ),
+        ),
+    ]

memberportal/api_billing/models.py

@@ -16,3 +16,49 @@ class ProcessedStripeEvent(models.Model):
     class Meta:
         verbose_name = "Processed Stripe Event"
         verbose_name_plural = "Processed Stripe Events"
+
+
+class PaymentPlanSwitchOperation(models.Model):
+    """Durable state for a Stripe subscription Price replacement.
+
+    The row is created before the Stripe mutation. If the request dies after
+    Stripe succeeds but before Profile is saved, the periodic reconciliation
+    task can inspect Stripe and finish the local update using this record.
+    """
+
+    STATUS_PENDING = "pending"
+    STATUS_FAILED = "failed"
+    STATUS_CHOICES = (
+        (STATUS_PENDING, "Pending"),
+        (STATUS_FAILED, "Failed"),
+    )
+
+    profile = models.OneToOneField(
+        "profile.Profile",
+        on_delete=models.CASCADE,
+        related_name="payment_plan_switch_operation",
+    )
+    current_plan = models.ForeignKey(
+        "api_admin_tools.PaymentPlan",
+        on_delete=models.PROTECT,
+        related_name="switch_operations_from",
+    )
+    target_plan = models.ForeignKey(
+        "api_admin_tools.PaymentPlan",
+        on_delete=models.PROTECT,
+        related_name="switch_operations_to",
+    )
+    stripe_subscription_id = models.CharField(max_length=100)
+    idempotency_key = models.CharField(max_length=255, unique=True)
+    status = models.CharField(
+        max_length=16,
+        choices=STATUS_CHOICES,
+        default=STATUS_PENDING,
+    )
+    attempt_count = models.PositiveIntegerField(default=0)
+    last_error = models.TextField(blank=True, default="")
+    created_at = models.DateTimeField(auto_now_add=True)
+    updated_at = models.DateTimeField(auto_now=True)
+
+    class Meta:
+        indexes = [models.Index(fields=["status", "updated_at"])]