fix: close position - support reduce-only

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "vertex-protocol"
-version = "3.1.6"
+version = "3.1.7"
 description = "Vertex Protocol SDK"
 authors = ["Jeury Mejia <jeury@vertexprotocol.com>"]
 homepage = "https://vertexprotocol.com/"

tests/engine_client/test_expiration.py

@@ -19,3 +19,21 @@ def test_expiration_encoding():
 
         assert decoded_unix_epoch == unix_epoch
         assert decoded_order_type == order_type
+
+
+def test_reduce_only():
+    unix_epoch = 1685939478
+
+    def is_reduce_only(expiration: int):
+        return (expiration & (1 << 61)) != 0
+
+    reduced_only_expiration = get_expiration_timestamp(
+        OrderType.FOK, unix_epoch, reduce_only=True
+    )
+    non_reduced_only_expiration = get_expiration_timestamp(OrderType.FOK, unix_epoch)
+
+    assert is_reduce_only(reduced_only_expiration)
+    assert not is_reduce_only(non_reduced_only_expiration)
+    assert not is_reduce_only(
+        get_expiration_timestamp(OrderType.FOK, unix_epoch, bool(None))
+    )

vertex_protocol/engine_client/execute.py

@@ -178,8 +178,7 @@ def place_market_order(self, params: PlaceMarketOrderParams) -> ExecuteResponse:
             nonce=params.market_order.nonce,
             priceX18=round_x18(market_price_x18, price_increment_x18),
             expiration=get_expiration_timestamp(
-                OrderType.FOK,
-                int(time.time()) + 1000,
+                OrderType.FOK, int(time.time()) + 1000, bool(params.reduce_only)
             ),
         )
         return self.place_order(
@@ -389,8 +388,7 @@ def close_position(
                         product.book_info.price_increment_x18,
                     ),
                     expiration=get_expiration_timestamp(
-                        OrderType.FOK,
-                        int(time.time()) + 1000,
+                        OrderType.FOK, int(time.time()) + 1000, reduce_only=True
                     ),
                 ),
             )

vertex_protocol/engine_client/types/execute.py

@@ -56,12 +56,15 @@ class PlaceMarketOrderParams(SignatureParams):
         market_order (MarketOrderParams): The parameters of the market order.
 
         spot_leverage (Optional[bool]): An optional flag indicating whether leverage should be used for the order. By default, leverage is assumed.
+
+        reduce_only (Optional[bool]): When True, the order can only reduce the size of an existing position. Works only with IOC & FOK.
     """
 
     product_id: int
     market_order: MarketOrderParams
     slippage: Optional[float]
     spot_leverage: Optional[bool]
+    reduce_only: Optional[bool]
 
 
 class CancelOrdersParams(BaseParamsSigned):

vertex_protocol/utils/expiration.py

@@ -8,7 +8,9 @@ class OrderType(IntEnum):
     POST_ONLY = 3
 
 
-def get_expiration_timestamp(order_type: OrderType, expiration: int) -> int:
+def get_expiration_timestamp(
+    order_type: OrderType, expiration: int, reduce_only: bool = False
+) -> int:
     """
     Encodes the order type into the expiration timestamp for special order types such as immediate-or-cancel.
 
@@ -17,10 +19,15 @@ def get_expiration_timestamp(order_type: OrderType, expiration: int) -> int:
 
         expiration (int): The expiration timestamp in UNIX seconds.
 
+        reduce_only (bool): When True, the order can only reduce the size of an existing position. Works only with IOC & FOK.
+
     Returns:
         int: The properly formatted timestamp needed for the specified order type.
     """
-    return int(expiration) | (order_type << 62)
+    expiration = int(expiration) | (order_type << 62)
+    if reduce_only:
+        expiration |= 1 << 61
+    return expiration
 
 
 def decode_expiration(expiration: int) -> tuple[OrderType, int]: