Capabilities#

Exchanges differ. One has funding-rate history, another does not. One streams private order updates, another only has REST. Instead of finding that out when a call fails in production, every adapter reports a capability matrix, similar to the has property in CCXT.

let caps = trader.capabilities();

if caps.is_supported("get_funding_rate_history") {
    let history = trader.get_funding_rate_history("BTCUSDT", 100).await?;
}

CapabilityStatus#

Each capability is one of four values:

Status	Meaning
`Supported`	Supported natively.
`Emulated`	Supported through a workaround.
`NotSupported`	The adapter does not support it.
`Unknown`	Not determined yet. This is the default.

Unknown is not "no". An adapter that has not declared a capability reports Unknown. Treat it as "not verified". Calling the method may still work, or may return a "not implemented" error.

ExchangeCapabilities#

ExchangeCapabilities is a struct with one CapabilityStatus field per capability. The fields fall in groups:

Group	Fields
Market types	`spot`, `swap`, `futures`, `option`, `margin`
Order creation	`create_market_order`, `create_limit_order`, `create_stop_market_order`, `create_stop_limit_order`, `create_take_profit_order`, `create_trailing_stop_order`, `create_post_only_order`, `create_reduce_only_order`, `create_orders_batch`
Order management	`cancel_order`, `cancel_all_orders`, `edit_order`
Order queries	`get_order_status`, `get_open_orders`, `get_order_history`, `get_order_trades`
Positions	`set_leverage`, `set_margin_mode`, `set_position_mode`, `close_position`, `get_position`, `get_positions`
Market data	`get_current_price`, `get_ticker`, `get_orderbook`, `get_ohlcv`, `get_trades`, `get_funding_rate`, `get_funding_rate_history`, `get_open_interest`, `get_open_interest_history`
Account	`get_balance`, `get_server_time`, `test_connection`
WebSocket	`ws_orderbook`, `ws_trades`, `ws_ticker`, `ws_orders`, `ws_positions`, `ws_balance`
Fast entry	`execute_fast_entry`, `format_symbol`
Transfers	`withdraw`, `get_deposit_address`, `transfer`

A field being present does not mean the trait has a method for it. Some capabilities describe features the SDK does not expose yet. Today the adapters declare a subset; see the exchange matrix.

Helper methods#

Method	Returns
`is_supported(name)`	`true` for `Supported` or `Emulated`. `name` is the snake_case field name. Unknown names return `false`.
`supported_count()`	How many capabilities are `Supported` or `Emulated`.
`total_count()`	How many capabilities exist.

Declaring capabilities in an adapter#

The exchange_capabilities! macro fills in the fields you list and leaves the rest Unknown:

use tradersdk_core::exchange_capabilities;

fn capabilities(&self) -> ExchangeCapabilities {
    exchange_capabilities! {
        spot: Supported,
        swap: Supported,
        ws_orderbook: NotSupported,
    }
}

See Adding an exchange.