Struct Cache 

pub struct Cache<T> { /* private fields */ }

A policy that caches successful results for a specified duration.

The cache stores the result of the first successful execution and returns it for subsequent calls until the TTL expires.

Note

This is a simple single-value cache. For more sophisticated caching (keyed cache, LRU eviction, etc.), consider using a dedicated caching library.

Examples

use do_over::{policy::Policy, cache::Cache, error::DoOverError};
use std::time::Duration;

let cache = Cache::<String>::new(Duration::from_secs(300));

// First call - executes operation
let result: Result<String, DoOverError<String>> = cache.execute(|| async {
    Ok("data".to_string())
}).await;

// Second call - returns cached value
let result: Result<String, DoOverError<String>> = cache.execute(|| async {
    panic!("This won't be called!");
}).await;

Implementations

impl<T> Cache<T>

where T: Clone + Send + Sync,

pub fn new(ttl: Duration) -> Self

Create a new cache policy.

Arguments

• ttl - Time-to-live for cached values

Examples

use do_over::cache::Cache;
use std::time::Duration;

// Cache for 5 minutes
let cache = Cache::<String>::new(Duration::from_secs(300));

// Cache for 1 hour
let cache = Cache::<Vec<u8>>::new(Duration::from_secs(3600));

pub async fn invalidate(&self)

Clear the cached value.

The next execution will call the underlying operation.

pub async fn has_cached_value(&self) -> bool

Check if there’s a valid cached value.

Trait Implementations

impl<T> Clone for Cache<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T, E> Policy<E> for Cache<T>

where T: Clone + Send + Sync, E: Send + Sync,

fn execute<'life0, 'async_trait, F, Fut, R>( &'life0 self, f: F, ) -> Pin<Box<dyn Future<Output = Result<R, E>> + Send + 'async_trait>>

where F: Fn() -> Fut + Send + Sync + 'async_trait, Fut: Future<Output = Result<R, E>> + Send + 'async_trait, R: Send + 'async_trait, Self: 'async_trait, 'life0: 'async_trait,

Execute an async operation with this policy’s resilience behavior.