Merge pull request #504 from Routstr/do-not-create-empty-token

no key creation when refund

routstr/balance.py

@@ -211,8 +211,20 @@ async def _refund_cache_set(authorization: str, value: dict[str, str]) -> None:
         _refund_cache[key] = (expiry, value)
 
 
+async def _lookup_key_no_create(
+    bearer_value: str, session: AsyncSession
+) -> ApiKey | None:
+    """Look up an existing API key without creating one Used by the refund endpoint"""
+    if bearer_value.startswith("sk-"):
+        return await session.get(ApiKey, bearer_value[3:])
+    if bearer_value.startswith("cashu"):
+        hashed = hashlib.sha256(bearer_value.encode()).hexdigest()
+        return await session.get(ApiKey, hashed)
+    return None
+
+
 async def _restore_balance(
-    session: AsyncSession, hashed_key: str, balance: int, reserved_balance: int
+    session: AsyncSession, hashed_key: str, balance: int, reserved_balance: int, mint_url: str
 ) -> None:
     """Restore balance after a failed refund mint attempt."""
     restore_stmt = (
@@ -227,7 +239,7 @@ async def _restore_balance(
     await session.commit()
     logger.info(
         "refund_wallet_endpoint: balance restored after mint failure",
-        extra={"hashed_key": hashed_key, "restored_balance": balance},
+        extra={"hashed_key": hashed_key, "restored_balance": balance, "mint_url": mint_url},
     )
 
 
@@ -282,7 +294,12 @@ async def refund_wallet_endpoint(
         )
 
     bearer_value: str = authorization[7:]
-    key: ApiKey = await validate_bearer_key(bearer_value, session)
+    key: ApiKey | None = await _lookup_key_no_create(bearer_value, session)
+    if key is None:
+        raise HTTPException(
+            status_code=401,
+            detail="Key not found. Deposit first via /v1/wallet/create before requesting a refund.",
+        )
 
     if key.total_balance <= 0:
         if cached := await _refund_cache_get(bearer_value):
@@ -373,11 +390,11 @@ async def refund_wallet_endpoint(
 
     except HTTPException:
         # Minting failed — restore the debited balance
-        await _restore_balance(session, key.hashed_key, pre_debit_balance, pre_debit_reserved)
+        await _restore_balance(session, key.hashed_key, pre_debit_balance, pre_debit_reserved, key.refund_mint_url or "")
         raise
     except Exception as e:
         # Minting failed — restore the debited balance
-        await _restore_balance(session, key.hashed_key, pre_debit_balance, pre_debit_reserved)
+        await _restore_balance(session, key.hashed_key, pre_debit_balance, pre_debit_reserved, key.refund_mint_url or "")
         error_msg = str(e)
         if (
             "mint" in error_msg.lower()

tests/integration/test_wallet_refund.py

@@ -372,17 +372,17 @@ async def test_refund_rejects_concurrent_topup_on_same_key(
     topup_amount_sat = 500
     topup_token = await testmint_wallet.mint_tokens(topup_amount_sat)
 
-    validate_called = asyncio.Event()
+    key_looked_up = asyncio.Event()
     allow_refund_to_continue = asyncio.Event()
-    original_validate_bearer_key = balance_module.validate_bearer_key
+    original_lookup = balance_module._lookup_key_no_create
     delayed_once = False
 
-    async def delayed_validate_bearer_key(*args: Any, **kwargs: Any) -> ApiKey:
+    async def delayed_lookup_key_no_create(*args: Any, **kwargs: Any) -> ApiKey | None:
         nonlocal delayed_once
-        key = await original_validate_bearer_key(*args, **kwargs)
-        if not delayed_once:
+        key = await original_lookup(*args, **kwargs)
+        if not delayed_once and key is not None:
             delayed_once = True
-            validate_called.set()
+            key_looked_up.set()
             await allow_refund_to_continue.wait()
         return key
 
@@ -390,7 +390,7 @@ async def test_refund_rejects_concurrent_topup_on_same_key(
         return await authenticated_client.post("/v1/wallet/refund")
 
     async def issue_topup() -> Any:
-        await validate_called.wait()
+        await key_looked_up.wait()
         try:
             return await authenticated_client.post(
                 "/v1/wallet/topup", params={"cashu_token": topup_token}
@@ -399,7 +399,7 @@ async def test_refund_rejects_concurrent_topup_on_same_key(
             allow_refund_to_continue.set()
 
     with patch(
-        "routstr.balance.validate_bearer_key", new=delayed_validate_bearer_key
+        "routstr.balance._lookup_key_no_create", new=delayed_lookup_key_no_create
     ):
         refund_response, topup_response = await asyncio.gather(
             issue_refund(), issue_topup()

tests/unit/test_balance.py

@@ -168,12 +168,12 @@ async def test_apikey_refund_stores_cashu_transaction_with_apikey_source() -> No
     refund_token = "cashuArefund_apikey_token"
 
     session = MagicMock()
+    session.get = AsyncMock(return_value=key)
     session.exec = AsyncMock(return_value=_update_result(1))
     session.add = MagicMock()
     session.commit = AsyncMock()
 
     with (
-        patch("routstr.balance.validate_bearer_key", AsyncMock(return_value=key)),
         patch("routstr.balance.get_billing_key", AsyncMock(return_value=key)),
         patch("routstr.balance.send_token", AsyncMock(return_value=refund_token)),
         patch("routstr.balance.store_cashu_transaction", AsyncMock()) as mock_store,
@@ -203,12 +203,12 @@ async def test_apikey_refund_logs_token() -> None:
     refund_token = "cashuAlogged_token"
 
     session = MagicMock()
+    session.get = AsyncMock(return_value=key)
     session.exec = AsyncMock(return_value=_update_result(1))
     session.add = MagicMock()
     session.commit = AsyncMock()
 
     with (
-        patch("routstr.balance.validate_bearer_key", AsyncMock(return_value=key)),
         patch("routstr.balance.get_billing_key", AsyncMock(return_value=key)),
         patch("routstr.balance.send_token", AsyncMock(return_value=refund_token)),
         patch("routstr.balance.store_cashu_transaction", AsyncMock()),
@@ -232,12 +232,12 @@ async def test_apikey_refund_log_includes_path() -> None:
     refund_token = "cashuApath_token"
 
     session = MagicMock()
+    session.get = AsyncMock(return_value=key)
     session.exec = AsyncMock(return_value=_update_result(1))
     session.add = MagicMock()
     session.commit = AsyncMock()
 
     with (
-        patch("routstr.balance.validate_bearer_key", AsyncMock(return_value=key)),
         patch("routstr.balance.get_billing_key", AsyncMock(return_value=key)),
         patch("routstr.balance.send_token", AsyncMock(return_value=refund_token)),
         patch("routstr.balance.store_cashu_transaction", AsyncMock()),
@@ -269,6 +269,7 @@ async def test_apikey_refund_rejects_on_concurrent_balance_change() -> None:
     key = _make_api_key(balance=5000, refund_currency="sat")
 
     session = MagicMock()
+    session.get = AsyncMock(return_value=key)
     # Debit returns rowcount=0 → balance changed concurrently
     session.exec = AsyncMock(return_value=_update_result(0))
     session.commit = AsyncMock()
@@ -276,7 +277,6 @@ async def test_apikey_refund_rejects_on_concurrent_balance_change() -> None:
     mock_send_token = AsyncMock(return_value="cashuAshould_not_be_minted")
 
     with (
-        patch("routstr.balance.validate_bearer_key", AsyncMock(return_value=key)),
         patch("routstr.balance.get_billing_key", AsyncMock(return_value=key)),
         patch("routstr.balance.send_token", mock_send_token),
         patch("routstr.balance.store_cashu_transaction", AsyncMock()),
@@ -333,11 +333,11 @@ async def test_apikey_refund_restores_balance_on_mint_failure() -> None:
 
     # First exec call = debit (succeeds), second = restore
     session = MagicMock()
+    session.get = AsyncMock(return_value=key)
     session.exec = AsyncMock(side_effect=[_update_result(1), _update_result(1)])
     session.commit = AsyncMock()
 
     with (
-        patch("routstr.balance.validate_bearer_key", AsyncMock(return_value=key)),
         patch("routstr.balance.get_billing_key", AsyncMock(return_value=key)),
         patch("routstr.balance.send_token", AsyncMock(side_effect=Exception("mint down"))),
         patch("routstr.balance.store_cashu_transaction", AsyncMock()),
@@ -355,3 +355,49 @@ async def test_apikey_refund_restores_balance_on_mint_failure() -> None:
     assert exc_info.value.status_code == 503
     # Verify two exec calls: debit + restore
     assert session.exec.await_count == 2
+
+
+# ---------------------------------------------------------------------------
+# no-create guarantee: fresh Cashu/unknown sk- tokens must not create API keys
+# ---------------------------------------------------------------------------
+
+
+@pytest.mark.asyncio
+async def test_refund_fresh_cashu_bearer_returns_401() -> None:
+    """Fresh Cashu token not in DB must get 401, never create a new ApiKey."""
+    from fastapi import HTTPException
+
+    session = MagicMock()
+    session.get = AsyncMock(return_value=None)
+
+    with pytest.raises(HTTPException) as exc_info:
+        await refund_wallet_endpoint(
+            authorization="Bearer cashuAfresh_never_deposited_token",
+            x_cashu=None,
+            session=session,
+        )
+
+    assert exc_info.value.status_code == 401
+    session.get.assert_awaited_once()
+    # No add/commit → no key was persisted
+    session.add.assert_not_called()
+    session.commit.assert_not_called()
+
+
+@pytest.mark.asyncio
+async def test_refund_unknown_sk_bearer_returns_401() -> None:
+    """Unknown sk- key not in DB must get 401."""
+    from fastapi import HTTPException
+
+    session = MagicMock()
+    session.get = AsyncMock(return_value=None)
+
+    with pytest.raises(HTTPException) as exc_info:
+        await refund_wallet_endpoint(
+            authorization="Bearer sk-unknownhash",
+            x_cashu=None,
+            session=session,
+        )
+
+    assert exc_info.value.status_code == 401
+    session.get.assert_awaited_once()