Trait CacheExt 

pub trait CacheExt: Cache {
    // Provided methods
    fn get_json<'life0, 'life1, 'async_trait, T>(
        &'life0 self,
        key: &'life1 str,
    ) -> Pin<Box<dyn Future<Output = Result<Option<T>>> + Send + 'async_trait>>
       where T: 'async_trait + DeserializeOwned,
             Self: Sync + 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait { ... }
    fn put_json<'life0, 'life1, 'life2, 'async_trait, T>(
        &'life0 self,
        key: &'life1 str,
        value: &'life2 T,
        ttl: Option<Duration>,
    ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>
       where T: 'async_trait + Serialize + Sync,
             Self: Sync + 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait { ... }
    fn get_string<'life0, 'life1, 'async_trait>(
        &'life0 self,
        key: &'life1 str,
    ) -> Pin<Box<dyn Future<Output = Result<Option<String>>> + Send + 'async_trait>>
       where Self: Sync + 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait { ... }
    fn put_string<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        key: &'life1 str,
        value: &'life2 str,
        ttl: Option<Duration>,
    ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>
       where Self: Sync + 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait { ... }
    fn add_string<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        key: &'life1 str,
        value: &'life2 str,
        ttl: Option<Duration>,
    ) -> Pin<Box<dyn Future<Output = Result<bool>> + Send + 'async_trait>>
       where Self: Sync + 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait { ... }
    fn decrement<'life0, 'life1, 'async_trait>(
        &'life0 self,
        key: &'life1 str,
        by: i64,
    ) -> Pin<Box<dyn Future<Output = Result<i64>> + Send + 'async_trait>>
       where Self: Sync + 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait { ... }
    fn remember<'life0, 'life1, 'async_trait, T, F, Fut>(
        &'life0 self,
        key: &'life1 str,
        ttl: Option<Duration>,
        compute: F,
    ) -> Pin<Box<dyn Future<Output = Result<T>> + Send + 'async_trait>>
       where T: Serialize + DeserializeOwned + Sync + Send + 'async_trait,
             F: FnOnce() -> Fut + Send + 'async_trait,
             Fut: Future<Output = Result<T>> + Send + 'async_trait,
             Self: Sync + 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait { ... }
    fn remember_forever<'life0, 'life1, 'async_trait, T, F, Fut>(
        &'life0 self,
        key: &'life1 str,
        compute: F,
    ) -> Pin<Box<dyn Future<Output = Result<T>> + Send + 'async_trait>>
       where T: Serialize + DeserializeOwned + Sync + Send + 'async_trait,
             F: FnOnce() -> Fut + Send + 'async_trait,
             Fut: Future<Output = Result<T>> + Send + 'async_trait,
             Self: Sync + 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait { ... }
}

The typed conveniences every Cache gets.

Kept out of the object-safe trait so Arc<dyn Cache> still exists.

Provided Methods

fn get_json<'life0, 'life1, 'async_trait, T>( &'life0 self, key: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<Option<T>>> + Send + 'async_trait>>

where T: 'async_trait + DeserializeOwned, Self: Sync + 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

A value, deserialised from JSON.

fn put_json<'life0, 'life1, 'life2, 'async_trait, T>( &'life0 self, key: &'life1 str, value: &'life2 T, ttl: Option<Duration>, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>

where T: 'async_trait + Serialize + Sync, Self: Sync + 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Store a value as JSON.

fn get_string<'life0, 'life1, 'async_trait>( &'life0 self, key: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<Option<String>>> + Send + 'async_trait>>

where Self: Sync + 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

A string value.

fn put_string<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, key: &'life1 str, value: &'life2 str, ttl: Option<Duration>, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>

where Self: Sync + 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Store a string.

fn add_string<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, key: &'life1 str, value: &'life2 str, ttl: Option<Duration>, ) -> Pin<Box<dyn Future<Output = Result<bool>> + Send + 'async_trait>>

where Self: Sync + 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Store a string only if the key is absent.

Cache::add with the encoding done for you. Atomic, like the method it calls.

fn decrement<'life0, 'life1, 'async_trait>( &'life0 self, key: &'life1 str, by: i64, ) -> Pin<Box<dyn Future<Output = Result<i64>> + Send + 'async_trait>>

where Self: Sync + 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Subtract from a counter.

fn remember<'life0, 'life1, 'async_trait, T, F, Fut>( &'life0 self, key: &'life1 str, ttl: Option<Duration>, compute: F, ) -> Pin<Box<dyn Future<Output = Result<T>> + Send + 'async_trait>>

where T: Serialize + DeserializeOwned + Sync + Send + 'async_trait, F: FnOnce() -> Fut + Send + 'async_trait, Fut: Future<Output = Result<T>> + Send + 'async_trait, Self: Sync + 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

The cached value at key, or compute it and cache that.

Laravel’s Cache::remember. The pattern nearly every cache use is, written once:

let settings: Settings = cache
    .remember("settings", Some(Duration::from_secs(300)), || async {
        load_settings(&database).await
    })
    .await?;

A failure is never cached

If compute returns an error, the error is returned and nothing is stored. Caching a failure for five minutes turns one bad second into five bad minutes, and the request that would have succeeded never gets to try. Cache a value; let the next caller retry.

A cached value that will not deserialise is treated as a miss and recomputed — see get_json.

It is not a lock

Ten simultaneous misses run compute ten times and the last write wins. That is the right trade for a cache: serialising them would mean nine requests waiting on a lock held by a tenth that might fail. When the computation is expensive enough that a stampede matters, take a Lock around it explicitly.

fn remember_forever<'life0, 'life1, 'async_trait, T, F, Fut>( &'life0 self, key: &'life1 str, compute: F, ) -> Pin<Box<dyn Future<Output = Result<T>> + Send + 'async_trait>>

where T: Serialize + DeserializeOwned + Sync + Send + 'async_trait, F: FnOnce() -> Fut + Send + 'async_trait, Fut: Future<Output = Result<T>> + Send + 'async_trait, Self: Sync + 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

remember, with no expiry.

Laravel’s rememberForever. For something that changes only when the application says so — and which therefore needs forget somewhere, or it is a leak with a nice name.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl<C: Cache + ?Sized> CacheExt for C