Struct HostVTable 

#[repr(C)]
pub struct HostVTable {

    pub abi_version: u32,
    pub clock_now_ns: unsafe extern "C" fn() -> u64,
    pub log: unsafe extern "C" fn(level: HostLogLevel, target: BorrowedStr<'_>, message: BorrowedStr<'_>),
    pub cache_instrument: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>,
    pub cache_account: unsafe extern "C" fn(ctx: *const HostContext, account_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>,
    pub cache_order: unsafe extern "C" fn(ctx: *const HostContext, client_order_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>,
    pub cache_position: unsafe extern "C" fn(ctx: *const HostContext, position_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>,
    pub cache_orders_for_strategy: unsafe extern "C" fn(ctx: *const HostContext, strategy_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>,
    pub cache_positions_for_strategy: unsafe extern "C" fn(ctx: *const HostContext, strategy_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>,
    pub subscribe_quotes: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>,
    pub unsubscribe_quotes: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>,
    pub subscribe_trades: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>,
    pub unsubscribe_trades: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>,
    pub subscribe_bars: unsafe extern "C" fn(ctx: *const HostContext, bar_type: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>,
    pub unsubscribe_bars: unsafe extern "C" fn(ctx: *const HostContext, bar_type: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>,
    pub subscribe_book_deltas: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, book_type: u8, depth: usize, client_id: BorrowedStr<'_>, managed: u8, params_json: BorrowedStr<'_>) -> PluginResult<()>,
    pub unsubscribe_book_deltas: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>,
    pub subscribe_book_at_interval: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, book_type: u8, depth: usize, interval_ms: usize, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>,
    pub unsubscribe_book_at_interval: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, interval_ms: usize, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>,
    pub msgbus_publish: unsafe extern "C" fn(ctx: *const HostContext, topic: BorrowedStr<'_>, payload: Slice<'_, u8>) -> PluginResult<()>,
    pub set_time_alert: unsafe extern "C" fn(ctx: *const HostContext, name: BorrowedStr<'_>, alert_time_ns: u64, allow_past: u8) -> PluginResult<()>,
    pub set_timer: unsafe extern "C" fn(ctx: *const HostContext, name: BorrowedStr<'_>, interval_ns: u64, start_time_ns: u64, stop_time_ns: u64, allow_past: u8, fire_immediately: u8) -> PluginResult<()>,
    pub cancel_timer: unsafe extern "C" fn(ctx: *const HostContext, name: BorrowedStr<'_>) -> PluginResult<()>,
    pub submit_order: unsafe extern "C" fn(ctx: *const HostContext, command: *const SubmitOrderHandle) -> PluginResult<()>,
    pub cancel_order: unsafe extern "C" fn(ctx: *const HostContext, command: *const CancelOrderHandle) -> PluginResult<()>,
    pub modify_order: unsafe extern "C" fn(ctx: *const HostContext, command: *const ModifyOrderHandle) -> PluginResult<()>,
    pub submit_order_list: unsafe extern "C" fn(ctx: *const HostContext, command: *const SubmitOrderListHandle) -> PluginResult<()>,
    pub cancel_orders: unsafe extern "C" fn(ctx: *const HostContext, command: *const CancelOrdersHandle) -> PluginResult<()>,
    pub cancel_all_orders: unsafe extern "C" fn(ctx: *const HostContext, command: *const CancelAllOrdersHandle) -> PluginResult<()>,
    pub close_position: unsafe extern "C" fn(ctx: *const HostContext, command: *const ClosePositionHandle) -> PluginResult<()>,
    pub close_all_positions: unsafe extern "C" fn(ctx: *const HostContext, command: *const CloseAllPositionsHandle) -> PluginResult<()>,
    pub query_account: unsafe extern "C" fn(ctx: *const HostContext, command: *const QueryAccountHandle) -> PluginResult<()>,
    pub query_order: unsafe extern "C" fn(ctx: *const HostContext, command: *const QueryOrderHandle) -> PluginResult<()>,
}

Function table the host passes to every plug-in at load time.

All function pointers are non-null and stable for the process lifetime. Plug-ins stash the pointer and call back through it whenever they need host services. Adding a method is a breaking ABI change and requires rebuilding plug-ins to match the host during alpha.

Fields

abi_version: u32

ABI version of this vtable. Must equal NAUTILUS_PLUGIN_ABI_VERSION.

clock_now_ns: unsafe extern "C" fn() -> u64

Returns the host’s monotonic clock reading in UNIX nanoseconds.

log: unsafe extern "C" fn(level: HostLogLevel, target: BorrowedStr<'_>, message: BorrowedStr<'_>)

Emits a log line to the host’s logger.

target is the log target (e.g. plug-in name), message is the body.

cache_instrument: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>

Returns the JSON-encoded instrument snapshot for instrument_id.

Empty bytes mean the cache had no matching instrument.

cache_account: unsafe extern "C" fn(ctx: *const HostContext, account_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>

Returns the JSON-encoded account snapshot for account_id.

Empty bytes mean the cache had no matching account.

cache_order: unsafe extern "C" fn(ctx: *const HostContext, client_order_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>

Returns the JSON-encoded order snapshot for client_order_id.

Empty bytes mean the cache had no matching order.

cache_position: unsafe extern "C" fn(ctx: *const HostContext, position_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>

Returns the JSON-encoded position snapshot for position_id.

Empty bytes mean the cache had no matching position.

cache_orders_for_strategy: unsafe extern "C" fn(ctx: *const HostContext, strategy_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>

Returns JSON-encoded order snapshots for the requested strategy.

Passing an empty strategy_id uses the calling strategy’s own ID.

cache_positions_for_strategy: unsafe extern "C" fn(ctx: *const HostContext, strategy_id: BorrowedStr<'_>) -> PluginResult<OwnedBytes>

Returns JSON-encoded position snapshots for the requested strategy.

Passing an empty strategy_id uses the calling strategy’s own ID.

subscribe_quotes: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>

Subscribes the calling actor or strategy to quote ticks.

unsubscribe_quotes: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>

Unsubscribes the calling actor or strategy from quote ticks.

subscribe_trades: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>

Subscribes the calling actor or strategy to trade ticks.

unsubscribe_trades: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>

Unsubscribes the calling actor or strategy from trade ticks.

subscribe_bars: unsafe extern "C" fn(ctx: *const HostContext, bar_type: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>

Subscribes the calling actor or strategy to bars.

unsubscribe_bars: unsafe extern "C" fn(ctx: *const HostContext, bar_type: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>

Unsubscribes the calling actor or strategy from bars.

subscribe_book_deltas: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, book_type: u8, depth: usize, client_id: BorrowedStr<'_>, managed: u8, params_json: BorrowedStr<'_>) -> PluginResult<()>

Subscribes the calling actor or strategy to order book deltas.

book_type uses the BookType discriminant. depth == 0 means no depth limit. managed != 0 requests a managed book subscription.

unsubscribe_book_deltas: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>

Unsubscribes the calling actor or strategy from order book deltas.

subscribe_book_at_interval: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, book_type: u8, depth: usize, interval_ms: usize, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>

Subscribes the calling actor or strategy to periodic order book snapshots.

book_type uses the BookType discriminant. depth == 0 means no depth limit. interval_ms must be greater than zero.

unsubscribe_book_at_interval: unsafe extern "C" fn(ctx: *const HostContext, instrument_id: BorrowedStr<'_>, interval_ms: usize, client_id: BorrowedStr<'_>, params_json: BorrowedStr<'_>) -> PluginResult<()>

Unsubscribes the calling actor or strategy from periodic order book snapshots.

interval_ms must be greater than zero.

msgbus_publish: unsafe extern "C" fn(ctx: *const HostContext, topic: BorrowedStr<'_>, payload: Slice<'_, u8>) -> PluginResult<()>

Publishes an arbitrary byte payload on the host message bus.

The payload is delivered as a Vec<u8> to subscribers of topic.

set_time_alert: unsafe extern "C" fn(ctx: *const HostContext, name: BorrowedStr<'_>, alert_time_ns: u64, allow_past: u8) -> PluginResult<()>

Registers a one-shot time alert on the calling actor or strategy clock.

set_timer: unsafe extern "C" fn(ctx: *const HostContext, name: BorrowedStr<'_>, interval_ns: u64, start_time_ns: u64, stop_time_ns: u64, allow_past: u8, fire_immediately: u8) -> PluginResult<()>

Registers an interval timer on the calling actor or strategy clock.

start_time_ns == 0 and stop_time_ns == 0 mean no explicit bound.

cancel_timer: unsafe extern "C" fn(ctx: *const HostContext, name: BorrowedStr<'_>) -> PluginResult<()>

Cancels a timer on the calling actor or strategy clock.

submit_order: unsafe extern "C" fn(ctx: *const HostContext, command: *const SubmitOrderHandle) -> PluginResult<()>

Submits an order on behalf of the calling strategy.

ctx is the HostContext the host passed into the strategy’s create. command is a boundary-owned SubmitOrderHandle the plug-in constructs around the order and its routing/position metadata. The plug-in owns the box and frees it when this call returns; the host only borrows the handle for the duration of the call.

cancel_order: unsafe extern "C" fn(ctx: *const HostContext, command: *const CancelOrderHandle) -> PluginResult<()>

Cancels an in-flight order on behalf of the calling strategy.

command is a boundary-owned CancelOrderHandle the plug-in constructs around the cancel parameters (typically client_order_id, optional client_id, optional venue params). The plug-in owns the box and frees it when this call returns; the host only borrows the handle for the duration of the call.

modify_order: unsafe extern "C" fn(ctx: *const HostContext, command: *const ModifyOrderHandle) -> PluginResult<()>

Modifies an in-flight order on behalf of the calling strategy.

command is a boundary-owned ModifyOrderHandle the plug-in constructs around the modify parameters (new quantity, price, trigger price, etc.). The plug-in owns the box and frees it when this call returns; the host only borrows the handle for the duration of the call.

submit_order_list: unsafe extern "C" fn(ctx: *const HostContext, command: *const SubmitOrderListHandle) -> PluginResult<()>

Submits a list of orders as a single batch on behalf of the calling strategy.

command is a boundary-owned SubmitOrderListHandle the plug-in constructs around the order list and optional position id, client id, and routing params. The host dispatches the batch atomically through the execution engine.

cancel_orders: unsafe extern "C" fn(ctx: *const HostContext, command: *const CancelOrdersHandle) -> PluginResult<()>

Cancels every order named in the supplied list on behalf of the calling strategy.

command is a boundary-owned CancelOrdersHandle carrying the client_order_id list plus optional client id and routing params.

cancel_all_orders: unsafe extern "C" fn(ctx: *const HostContext, command: *const CancelAllOrdersHandle) -> PluginResult<()>

Cancels every open order matching the supplied filter on behalf of the calling strategy.

command is a boundary-owned CancelAllOrdersHandle carrying the instrument_id and optional order_side, client_id, and routing params. The host scans its cache for matching open orders and issues the cancels.

close_position: unsafe extern "C" fn(ctx: *const HostContext, command: *const ClosePositionHandle) -> PluginResult<()>

Closes the position identified by the command on behalf of the calling strategy.

command is a boundary-owned ClosePositionHandle carrying the position_id plus optional client_id, tags, time_in_force, reduce_only, and quote_quantity. The host reads the position from its cache and submits a closing market order through the strategy’s order factory.

close_all_positions: unsafe extern "C" fn(ctx: *const HostContext, command: *const CloseAllPositionsHandle) -> PluginResult<()>

Closes every open position matching the supplied filter on behalf of the calling strategy.

command is a boundary-owned CloseAllPositionsHandle carrying the instrument_id plus optional position_side, client_id, tags, time_in_force, reduce_only, and quote_quantity. The host scans its cache for matching open positions and submits closing market orders.

query_account: unsafe extern "C" fn(ctx: *const HostContext, command: *const QueryAccountHandle) -> PluginResult<()>

Queries the venue for the latest snapshot of account_id on behalf of the calling strategy.

command is a boundary-owned QueryAccountHandle carrying the account_id plus optional client_id and routing params. The result is delivered asynchronously through the host’s normal account-state event flow; this call only fires the query, it does not return the snapshot inline.

query_order: unsafe extern "C" fn(ctx: *const HostContext, command: *const QueryOrderHandle) -> PluginResult<()>

Queries the venue for the latest snapshot of client_order_id on behalf of the calling strategy.

command is a boundary-owned QueryOrderHandle carrying the client_order_id plus optional client_id and routing params. The result is delivered asynchronously through the host’s normal order-status event flow; this call only fires the query, it does not return the snapshot inline.

Implementations

impl HostVTable

pub fn matches_compiled_abi(&self) -> bool

Asserts that the embedded ABI version matches the compiled-in constant.

Plug-ins should call this in their nautilus_plugin_init body before trusting any function pointer from the table.

pub unsafe fn now_ns(&self) -> u64

Reads the clock through the vtable.

Safety

The vtable pointer must originate from the host’s nautilus_plugin_init call and the host’s library must still be live.

pub unsafe fn log_message( &self, level: HostLogLevel, target: &str, message: &str, )

Logs message at level through the vtable.

Safety

See HostVTable::now_ns.

Trait Implementations

impl Send for HostVTable

SAFETY: function pointers are thread-safe by construction; the host guarantees the underlying implementations are Sync.

impl Sync for HostVTable

SAFETY: see above.