feat: self-serve signup Phase 2 (frontend cutover) (#162)

Co-authored-by: Michael Chihlas <michael@resolutionflow.com>
Co-committed-by: Michael Chihlas <michael@resolutionflow.com>

backend/tests/test_billing_portal.py

@@ -0,0 +1,83 @@
+import uuid
+import pytest
+from unittest.mock import patch, MagicMock
+from sqlalchemy import select
+
+from app.models.account import Account
+
+
+@pytest.mark.asyncio
+async def test_billing_portal_returns_url_for_account_with_stripe_customer(
+    client, test_db, test_user, auth_headers, monkeypatch
+):
+    """Happy path: account has a stripe_customer_id and Stripe is configured →
+    GET /billing/portal-session returns the portal URL."""
+    from app.core.config import settings
+    monkeypatch.setattr(settings, "STRIPE_SECRET_KEY", "sk_test_dummy")
+    monkeypatch.setattr(settings, "FRONTEND_URL", "https://app.example.com")
+
+    account_id = uuid.UUID(test_user["user_data"]["account_id"])
+    account = (await test_db.execute(
+        select(Account).where(Account.id == account_id)
+    )).scalar_one()
+    account.stripe_customer_id = "cus_test_456"
+    await test_db.commit()
+
+    fake_session = MagicMock()
+    fake_session.url = "https://billing.stripe.com/p/session/test_abc"
+
+    with patch(
+        "stripe.billing_portal.Session.create",
+        return_value=fake_session,
+    ) as portal_mock:
+        response = await client.get(
+            "/api/v1/billing/portal-session",
+            headers=auth_headers,
+        )
+
+    assert response.status_code == 200, response.json()
+    assert response.json() == {"url": "https://billing.stripe.com/p/session/test_abc"}
+    portal_mock.assert_called_once()
+    call_kwargs = portal_mock.call_args.kwargs
+    assert call_kwargs["customer"] == "cus_test_456"
+    assert call_kwargs["return_url"] == "https://app.example.com/account/billing"
+
+
+@pytest.mark.asyncio
+async def test_billing_portal_returns_503_when_stripe_not_configured(
+    client, test_db, test_user, auth_headers, monkeypatch
+):
+    """STRIPE_SECRET_KEY unset → settings.stripe_enabled is False → 503."""
+    from app.core.config import settings
+    monkeypatch.setattr(settings, "STRIPE_SECRET_KEY", None)
+
+    response = await client.get(
+        "/api/v1/billing/portal-session",
+        headers=auth_headers,
+    )
+    assert response.status_code == 503
+    assert response.json()["detail"]["error"] == "stripe_not_configured"
+
+
+@pytest.mark.asyncio
+async def test_billing_portal_returns_400_when_account_has_no_stripe_customer(
+    client, test_db, test_user, auth_headers, monkeypatch
+):
+    """Account with no stripe_customer_id (never completed checkout) → 400
+    with `no_stripe_customer` error."""
+    from app.core.config import settings
+    monkeypatch.setattr(settings, "STRIPE_SECRET_KEY", "sk_test_dummy")
+
+    # test_user fixture seeds an account with no stripe_customer_id by default.
+    account_id = uuid.UUID(test_user["user_data"]["account_id"])
+    account = (await test_db.execute(
+        select(Account).where(Account.id == account_id)
+    )).scalar_one()
+    assert account.stripe_customer_id is None
+
+    response = await client.get(
+        "/api/v1/billing/portal-session",
+        headers=auth_headers,
+    )
+    assert response.status_code == 400
+    assert response.json()["detail"]["error"] == "no_stripe_customer"