Struct InstrumentCache 

pub struct InstrumentCache { /* private fields */ }

A cache of instrument metadata with a caller-driven refresh clock.

The refresh decision takes the current time as an argument rather than reading a hidden clock, so staleness logic is deterministic and testable.

Implementations

impl InstrumentCache

pub fn new() -> InstrumentCache

An empty cache.

pub fn replace( &mut self, instruments: impl IntoIterator<Item = Instrument>, now_ms: i64, )

Replace the cache contents with a freshly fetched set, stamping the fetch time (milliseconds since the Unix epoch).

pub fn get(&self, symbol: &Symbol) -> Option<&Instrument>

Look up an instrument by symbol.

pub fn len(&self) -> usize

The number of cached instruments.

pub fn is_empty(&self) -> bool

Whether the cache is empty.

pub fn needs_refresh(&self, now_ms: i64, ttl_ms: i64) -> bool

Whether the cache should be refreshed: never fetched, or older than ttl_ms relative to now_ms.

Trait Implementations

impl Debug for InstrumentCache

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for InstrumentCache

fn default() -> InstrumentCache

Returns the “default value” for a type.