✅ Order Check¶

Request: dry‑run a trade request (market/pending/modify/close_by) and get required margin, free margin after, and a return code — without actually placing anything.

Source files (SDK):

MetaRpcMT5/mt5_account.py — method order_check(...)
MetaRpcMT5/mt5_term_api_trade_functions_pb2.py — OrderCheck*, MrpcMqlTradeRequest, MrpcMqlTradeCheckResult, enums: MRPC_ENUM_TRADE_REQUEST_ACTIONS, ENUM_ORDER_TYPE_TF, MRPC_ENUM_ORDER_TYPE_FILLING, MRPC_ENUM_ORDER_TYPE_TIME
MetaRpcMT5/mt5_term_api_trade_functions_pb2_grpc.py — service stub TradeFunctionsStub

RPC¶

Service: mt5_term_api.TradeFunctions
Method: OrderCheck(OrderCheckRequest) → OrderCheckReply
Low-level client: TradeFunctionsStub.OrderCheck(request, metadata, timeout)
SDK wrapper: MT5Account.order_check(request, deadline=None, cancellation_event=None) → OrderCheckData

Method Signature¶

async def order_check(
    self,
    request: trade_functions_pb2.OrderCheckRequest,
    deadline: datetime | None = None,
    cancellation_event: asyncio.Event | None = None,
) -> trade_functions_pb2.OrderCheckData

💬 Just about the main thing¶

What it is. Server‑side pre‑validation of a trade request (like MT5 OrderCheck): returns margins & a code.
Why. Use it to fail fast in UI/strategies before OrderSend — avoid rejections and needless noise.
Be careful.
You must build MrpcMqlTradeRequest correctly (action/type/volume/price/SL/TP/filling/time/etc.).
It does not place or modify anything — numbers are estimates for current market state.

🔗 Code Example¶

# Minimal: check if a market BUY 0.10 is ok, with 20pt deviation
from MetaRpcMT5 import mt5_term_api_trade_functions_pb2 as tf_pb2
from google.protobuf.timestamp_pb2 import Timestamp

rq = tf_pb2.MrpcMqlTradeRequest(
    action=tf_pb2.MRPC_ENUM_TRADE_REQUEST_ACTIONS.TRADE_ACTION_DEAL,
    symbol="EURUSD",
    volume=0.10,
    order_type=tf_pb2.ENUM_ORDER_TYPE_TF.ORDER_TYPE_TF_BUY,
    price=0.0,              # market; server will use current price
    deviation=20,
    type_filling=tf_pb2.MRPC_ENUM_ORDER_TYPE_FILLING.ORDER_FILLING_IOC,
    type_time=tf_pb2.MRPC_ENUM_ORDER_TYPE_TIME.ORDER_TIME_GTC,
    comment="preflight",
)
res = await acct.order_check(tf_pb2.OrderCheckRequest(mql_trade_request=rq))
chk = res.mql_trade_check_result
print(chk.retcode, chk.margin, chk.free_margin)  # numeric code + margins

# Pending BUY_LIMIT with expiration today (SPECIFIED_DAY)
from datetime import datetime, timezone
from google.protobuf.timestamp_pb2 import Timestamp
from MetaRpcMT5 import mt5_term_api_trade_functions_pb2 as tf_pb2

exp = Timestamp(); exp.FromDatetime(datetime.now(timezone.utc).replace(hour=21, minute=0, second=0, microsecond=0))

rq = tf_pb2.MrpcMqlTradeRequest(
    action=tf_pb2.MRPC_ENUM_TRADE_REQUEST_ACTIONS.TRADE_ACTION_PENDING,
    symbol="XAUUSD",
    volume=0.10,
    order_type=tf_pb2.ENUM_ORDER_TYPE_TF.ORDER_TYPE_TF_BUY_LIMIT,
    price=2300.00,
    stop_loss=2290.00,
    take_profit=2320.00,
    type_time=tf_pb2.MRPC_ENUM_ORDER_TYPE_TIME.ORDER_TIME_SPECIFIED_DAY,
    expiration=exp,
    comment="limit preflight",
)
res = await acct.order_check(tf_pb2.OrderCheckRequest(mql_trade_request=rq))
print(res.mql_trade_check_result.retcode)

🔽 Input¶

Parameter	Type	Description
`request`	`OrderCheckRequest` (required)	Wraps your `MrpcMqlTradeRequest` (see below).
`deadline`	`datetime \\| None`	Absolute per‑call deadline → timeout.
`cancellation_event`	`asyncio.Event \\| None`	Cooperative cancel for the retry wrapper.

Request message: OrderCheckRequest { mql_trade_request: MrpcMqlTradeRequest }

Message: `MrpcMqlTradeRequest`¶

#	Field	Proto Type	Notes
1	`action`	`enum MRPC_ENUM_TRADE_REQUEST_ACTIONS`	DEAL/PENDING/SLTP/MODIFY/REMOVE/CLOSE_BY
2	`magic`	`uint64`	Expert Advisor magic id
3	`order`	`uint64`	Order ticket (when applicable)
4	`symbol`	`string`	Symbol name
5	`volume`	`double`	Lots
6	`price`	`double`	Entry/close price; `0.0` for market
7	`stop_limit`	`double`	Stop‑limit trigger (for *_STOP_LIMIT)
8	`stop_loss`	`double`	SL
9	`take_profit`	`double`	TP
10	`deviation`	`uint32`	Max deviation in points (market ops)
11	`order_type`	`enum ENUM_ORDER_TYPE_TF`	BUY/SELL/LIMIT/STOP/STOP_LIMIT/CLOSE_BY
12	`type_filling`	`enum MRPC_ENUM_ORDER_TYPE_FILLING`	FOK/IOC/RETURN/BOC
13	`type_time`	`enum MRPC_ENUM_ORDER_TYPE_TIME`	GTC/DAY/SPECIFIED/SPECIFIED_DAY
14	`expiration`	`google.protobuf.Timestamp`	Expiration (UTC)
15	`comment`	`string`	Optional note
16	`position`	`uint64`	Position ticket (when applicable)
17	`position_by`	`uint64`	Close‑by ticket

⬆️ Output¶

Payload: `OrderCheckData`¶

Field	Proto Type	Description
`mql_trade_check_result`	`MrpcMqlTradeCheckResult`	Result bundle below

Message: `MrpcMqlTradeCheckResult`¶

#	Field	Proto Type	Description
1	`retcode`	`uint32`	Numeric return code (0 = ok; non‑zero → error/warning).
2	`balance_after_deal`	`double`	Balance projected after execution.
3	`equity_after_deal`	`double`	Equity projected after execution.
4	`profit`	`double`	Expected P/L (may be 0 for opens).
5	`margin`	`double`	Required margin for this request.
6	`free_margin`	`double`	Free margin projected after execution.
7	`margin_level`	`double`	Margin level % after execution.
8	`comment`	`string`	Text explanation from server.

Wire reply: OrderCheckReply { data: OrderCheckData, error: Error? } SDK returns reply.data.

Enums¶

`MRPC_ENUM_TRADE_REQUEST_ACTIONS`¶

Number	Value	Meaning
0	`TRADE_ACTION_DEAL`	Market operation (open/close).
1	`TRADE_ACTION_PENDING`	Place/alter pending order.
2	`TRADE_ACTION_SLTP`	SL/TP change.
3	`TRADE_ACTION_MODIFY`	Generic modify.
4	`TRADE_ACTION_REMOVE`	Remove pending.
5	`TRADE_ACTION_CLOSE_BY`	Close by opposite position.

`ENUM_ORDER_TYPE_TF`¶

Number	Value
0	`ORDER_TYPE_TF_BUY`
1	`ORDER_TYPE_TF_SELL`
2	`ORDER_TYPE_TF_BUY_LIMIT`
3	`ORDER_TYPE_TF_SELL_LIMIT`
4	`ORDER_TYPE_TF_BUY_STOP`
5	`ORDER_TYPE_TF_SELL_STOP`
6	`ORDER_TYPE_TF_BUY_STOP_LIMIT`
7	`ORDER_TYPE_TF_SELL_STOP_LIMIT`
8	`ORDER_TYPE_TF_CLOSE_BY`

`MRPC_ENUM_ORDER_TYPE_FILLING`¶

Number	Value
0	`ORDER_FILLING_FOK`
1	`ORDER_FILLING_IOC`
2	`ORDER_FILLING_RETURN`
3	`ORDER_FILLING_BOC`

`MRPC_ENUM_ORDER_TYPE_TIME`¶

Number	Value
0	`ORDER_TIME_GTC`
1	`ORDER_TIME_DAY`
2	`ORDER_TIME_SPECIFIED`
3	`ORDER_TIME_SPECIFIED_DAY`

🎯 Purpose¶

Pre‑flight validation for OrderSend/OrderModify in UI and algos.
Show required margin/free margin after before committing.
Explain failures to users via retcode + comment.

🧩 Notes & Tips¶

Use symbol_info_margin_rate/symbol_info_double(SYMBOL_TRADE_CONTRACT_SIZE) to cross‑check expectations.
Always set type_filling/type_time deliberately; brokers differ.

Usage Examples¶

1) Check partial close feasibility¶

from MetaRpcMT5 import mt5_term_api_trade_functions_pb2 as tf_pb2
rq = tf_pb2.MrpcMqlTradeRequest(
    action=tf_pb2.MRPC_ENUM_TRADE_REQUEST_ACTIONS.TRADE_ACTION_DEAL,
    symbol="EURUSD",
    volume=0.05,
    order_type=tf_pb2.ENUM_ORDER_TYPE_TF.ORDER_TYPE_TF_SELL,  # closing BUY position
    price=0.0,
    deviation=15,
)
res = await acct.order_check(tf_pb2.OrderCheckRequest(mql_trade_request=rq))
print(res.mql_trade_check_result.free_margin)

2) Validate SL/TP modification¶

rq = tf_pb2.MrpcMqlTradeRequest(
    action=tf_pb2.MRPC_ENUM_TRADE_REQUEST_ACTIONS.TRADE_ACTION_SLTP,
    symbol="XAUUSD",
    stop_loss=2288.0,
    take_profit=2325.0,
)
res = await acct.order_check(tf_pb2.OrderCheckRequest(mql_trade_request=rq))
print(res.mql_trade_check_result.retcode, res.mql_trade_check_result.comment)

3) Pending STOP_LIMIT with stop trigger¶

rq = tf_pb2.MrpcMqlTradeRequest(
    action=tf_pb2.MRPC_ENUM_TRADE_REQUEST_ACTIONS.TRADE_ACTION_PENDING,
    symbol="BTCUSD",
    volume=0.03,
    order_type=tf_pb2.ENUM_ORDER_TYPE_TF.ORDER_TYPE_TF_BUY_STOP_LIMIT,
    price=65000.0,          # limit price
    stop_limit=64950.0,     # stop trigger
)
res = await acct.order_check(tf_pb2.OrderCheckRequest(mql_trade_request=rq))
print(res.mql_trade_check_result.margin)

✅ Order Check¶

RPC¶

Method Signature¶

💬 Just about the main thing¶

🔗 Code Example¶

🔽 Input¶

Message: MrpcMqlTradeRequest¶

⬆️ Output¶

Payload: OrderCheckData¶

Message: MrpcMqlTradeCheckResult¶

Enums¶

MRPC_ENUM_TRADE_REQUEST_ACTIONS¶

ENUM_ORDER_TYPE_TF¶

MRPC_ENUM_ORDER_TYPE_FILLING¶

MRPC_ENUM_ORDER_TYPE_TIME¶

🎯 Purpose¶

🧩 Notes & Tips¶

Usage Examples¶

1) Check partial close feasibility¶

2) Validate SL/TP modification¶

3) Pending STOP_LIMIT with stop trigger¶

Message: `MrpcMqlTradeRequest`¶

Payload: `OrderCheckData`¶

Message: `MrpcMqlTradeCheckResult`¶

`MRPC_ENUM_TRADE_REQUEST_ACTIONS`¶

`ENUM_ORDER_TYPE_TF`¶

`MRPC_ENUM_ORDER_TYPE_FILLING`¶

`MRPC_ENUM_ORDER_TYPE_TIME`¶