fix(backend): guard get_proration_credit_cents against creating orphaned Stripe customers

get_proration_credit_cents now checks user.stripe_customer_id before calling into
Stripe, matching the same pattern applied to cancel_stripe_subscription. Admin-granted
paid-tier users without a Stripe record previously triggered customer creation on every
billing page load; they now get 0 immediately.

Also adds tests: no_customer_id fast-path for cancel, and three proration scenarios
(zero cost, no customer id, active subscription with proration calculation).

autogpt_platform/backend/backend/data/credit.py

@@ -1385,8 +1385,14 @@ async def get_proration_credit_cents(user_id: str, monthly_cost_cents: int) -> i
     """
     if monthly_cost_cents <= 0:
         return 0
+    # Guard: only query Stripe if the user already has a customer ID.  Admin-granted
+    # paid tiers have no Stripe record; calling get_stripe_customer_id would create an
+    # orphaned customer on every billing-page load for those users.
+    user = await get_user_by_id(user_id)
+    if not user.stripe_customer_id:
+        return 0
     try:
-        customer_id = await get_stripe_customer_id(user_id)
+        customer_id = user.stripe_customer_id
         subscriptions = await run_in_threadpool(
             stripe.Subscription.list, customer=customer_id, status="active", limit=1
         )

autogpt_platform/backend/backend/data/credit_subscription_test.py

@@ -12,6 +12,7 @@ from prisma.models import User
 from backend.data.credit import (
     cancel_stripe_subscription,
     create_subscription_checkout,
+    get_proration_credit_cents,
     handle_subscription_payment_failure,
     modify_stripe_subscription_for_tier,
     set_subscription_tier,
@@ -299,6 +300,13 @@ async def test_sync_subscription_from_stripe_unknown_customer():
         await sync_subscription_from_stripe(stripe_sub)
 
 
+def _make_user_with_stripe(stripe_customer_id: str | None = "cus_123") -> MagicMock:
+    """Return a mock model.User with the given stripe_customer_id."""
+    mock_user = MagicMock()
+    mock_user.stripe_customer_id = stripe_customer_id
+    return mock_user
+
+
 @pytest.mark.asyncio
 async def test_cancel_stripe_subscription_cancels_active():
     mock_subscriptions = MagicMock()
@@ -307,9 +315,9 @@ async def test_cancel_stripe_subscription_cancels_active():
 
     with (
         patch(
-            "backend.data.credit.get_stripe_customer_id",
+            "backend.data.credit.get_user_by_id",
             new_callable=AsyncMock,
-            return_value="cus_123",
+            return_value=_make_user_with_stripe("cus_123"),
         ),
         patch(
             "backend.data.credit.stripe.Subscription.list",
@@ -321,6 +329,19 @@ async def test_cancel_stripe_subscription_cancels_active():
         mock_modify.assert_called_once_with("sub_abc123", cancel_at_period_end=True)
 
 
+@pytest.mark.asyncio
+async def test_cancel_stripe_subscription_no_customer_id_returns_false():
+    """Users with no stripe_customer_id return False without creating a Stripe customer."""
+    result = False
+    with patch(
+        "backend.data.credit.get_user_by_id",
+        new_callable=AsyncMock,
+        return_value=_make_user_with_stripe(stripe_customer_id=None),
+    ):
+        result = await cancel_stripe_subscription("user-1")
+    assert result is False
+
+
 @pytest.mark.asyncio
 async def test_cancel_stripe_subscription_multi_partial_failure():
     """First modify raises → error propagates and subsequent subs are not scheduled."""
@@ -330,9 +351,9 @@ async def test_cancel_stripe_subscription_multi_partial_failure():
 
     with (
         patch(
-            "backend.data.credit.get_stripe_customer_id",
+            "backend.data.credit.get_user_by_id",
             new_callable=AsyncMock,
-            return_value="cus_123",
+            return_value=_make_user_with_stripe("cus_123"),
         ),
         patch(
             "backend.data.credit.stripe.Subscription.list",
@@ -368,9 +389,9 @@ async def test_cancel_stripe_subscription_no_active():
 
     with (
         patch(
-            "backend.data.credit.get_stripe_customer_id",
+            "backend.data.credit.get_user_by_id",
             new_callable=AsyncMock,
-            return_value="cus_123",
+            return_value=_make_user_with_stripe("cus_123"),
         ),
         patch(
             "backend.data.credit.stripe.Subscription.list",
@@ -387,9 +408,9 @@ async def test_cancel_stripe_subscription_raises_on_list_failure():
     """stripe.Subscription.list() failure propagates so DB tier is not updated."""
     with (
         patch(
-            "backend.data.credit.get_stripe_customer_id",
+            "backend.data.credit.get_user_by_id",
             new_callable=AsyncMock,
-            return_value="cus_123",
+            return_value=_make_user_with_stripe("cus_123"),
         ),
         patch(
             "backend.data.credit.stripe.Subscription.list",
@@ -415,9 +436,9 @@ async def test_cancel_stripe_subscription_cancels_trialing():
 
     with (
         patch(
-            "backend.data.credit.get_stripe_customer_id",
+            "backend.data.credit.get_user_by_id",
             new_callable=AsyncMock,
-            return_value="cus_123",
+            return_value=_make_user_with_stripe("cus_123"),
         ),
         patch(
             "backend.data.credit.stripe.Subscription.list",
@@ -444,9 +465,9 @@ async def test_cancel_stripe_subscription_cancels_active_and_trialing():
 
     with (
         patch(
-            "backend.data.credit.get_stripe_customer_id",
+            "backend.data.credit.get_user_by_id",
             new_callable=AsyncMock,
-            return_value="cus_123",
+            return_value=_make_user_with_stripe("cus_123"),
         ),
         patch(
             "backend.data.credit.stripe.Subscription.list",
@@ -459,6 +480,62 @@ async def test_cancel_stripe_subscription_cancels_active_and_trialing():
         assert modified_ids == {"sub_active_1", "sub_trial_2"}
 
 
+@pytest.mark.asyncio
+async def test_get_proration_credit_cents_no_stripe_customer_returns_zero():
+    """Admin-granted tier users without stripe_customer_id get 0 without creating a customer."""
+    with patch(
+        "backend.data.credit.get_user_by_id",
+        new_callable=AsyncMock,
+        return_value=_make_user_with_stripe(stripe_customer_id=None),
+    ) as mock_user:
+        result = await get_proration_credit_cents("user-1", monthly_cost_cents=2000)
+    assert result == 0
+    mock_user.assert_awaited_once_with("user-1")
+
+
+@pytest.mark.asyncio
+async def test_get_proration_credit_cents_zero_cost_returns_zero():
+    """FREE tier users (cost=0) return 0 without calling get_user_by_id."""
+    with patch(
+        "backend.data.credit.get_user_by_id", new_callable=AsyncMock
+    ) as mock_get_user:
+        result = await get_proration_credit_cents("user-1", monthly_cost_cents=0)
+    assert result == 0
+    mock_get_user.assert_not_awaited()
+
+
+@pytest.mark.asyncio
+async def test_get_proration_credit_cents_with_active_sub():
+    """User with active sub returns prorated credit based on remaining billing period."""
+    import time
+
+    now = int(time.time())
+    period_start = now - 15 * 24 * 3600  # 15 days ago
+    period_end = now + 15 * 24 * 3600  # 15 days ahead
+    mock_sub = {
+        "id": "sub_abc",
+        "current_period_start": period_start,
+        "current_period_end": period_end,
+    }
+    mock_subs = MagicMock()
+    mock_subs.data = [mock_sub]
+
+    with (
+        patch(
+            "backend.data.credit.get_user_by_id",
+            new_callable=AsyncMock,
+            return_value=_make_user_with_stripe("cus_123"),
+        ),
+        patch(
+            "backend.data.credit.stripe.Subscription.list",
+            return_value=mock_subs,
+        ),
+    ):
+        result = await get_proration_credit_cents("user-1", monthly_cost_cents=2000)
+    assert result > 0
+    assert result < 2000
+
+
 @pytest.mark.asyncio
 async def test_create_subscription_checkout_returns_url():
     mock_session = MagicMock()
@@ -806,9 +883,9 @@ async def test_cancel_stripe_subscription_raises_on_cancel_error():
 
     with (
         patch(
-            "backend.data.credit.get_stripe_customer_id",
+            "backend.data.credit.get_user_by_id",
             new_callable=AsyncMock,
-            return_value="cus_123",
+            return_value=_make_user_with_stripe("cus_123"),
         ),
         patch(
             "backend.data.credit.stripe.Subscription.list",