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TimeProvider

moonpool_core

Trait TimeProvider 

Source 
pub trait TimeProvider: Clone {
    // Required methods
    fn sleep<'life0, 'async_trait>(
        &'life0 self,
        duration: Duration,
    ) -> Pin<Box<dyn Future<Output = Result<(), TimeError>> + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;
    fn now(&self) -> Duration;
    fn timer(&self) -> Duration;
    fn timeout<'life0, 'async_trait, F, T>(
        &'life0 self,
        duration: Duration,
        future: F,
    ) -> Pin<Box<dyn Future<Output = Result<T, TimeError>> + 'async_trait>>
       where F: Future<Output = T> + 'async_trait,
             T: 'async_trait,
             Self: 'async_trait,
             'life0: 'async_trait;
}
Expand description

Provider trait for time operations.

This trait allows code to work with both simulation time and real wall-clock time in a unified way. Implementations handle sleeping and getting current time appropriate for their environment.

§Time Semantics

  • now(): Returns the exact, canonical time. Use this for scheduling and precise comparisons.
  • timer(): Returns a potentially drifted time that can be slightly ahead of now(). In simulation, this simulates real-world clock drift. In production, this equals now().

FDB ref: sim2.actor.cpp:1056-1064

Required Methods§

Source

fn sleep<'life0, 'async_trait>( &'life0 self, duration: Duration, ) -> Pin<Box<dyn Future<Output = Result<(), TimeError>> + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait,

Sleep for the specified duration.

In simulation, this advances simulation time. In real time, this uses actual wall-clock delays.

Source

fn now(&self) -> Duration

Get exact current time.

In simulation, this returns the canonical simulation time. In real time, this returns wall-clock elapsed time since provider creation.

Use this for precise time comparisons and event scheduling.

Source

fn timer(&self) -> Duration

Get drifted timer time.

In simulation, this can be up to clock_drift_max (default 100ms) ahead of now(). This simulates real-world clock drift between processes. In real time, this equals now().

Use this for time-sensitive application logic like timeouts, leases, and heartbeats to test how code handles clock drift.

FDB ref: sim2.actor.cpp:1058-1064

Source

fn timeout<'life0, 'async_trait, F, T>( &'life0 self, duration: Duration, future: F, ) -> Pin<Box<dyn Future<Output = Result<T, TimeError>> + 'async_trait>>
where F: Future<Output = T> + 'async_trait, T: 'async_trait, Self: 'async_trait, 'life0: 'async_trait,

Run a future with a timeout.

Returns Ok(result) if the future completes within the timeout, or Err(TimeError::Elapsed) if it times out.

Dyn Compatibility§

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors§