CrudeCache

CrudeCache is a simple utility for good enough concurrent caching needs. Inspired by Play Framework's cache.getOrElseUpdate.

//Returns non-expired cached item. If one does not exist, new item will be cached & returned
cache.get_or_else_update("cache_key", Duration::from_secs(60), async_function).await

Disclaimer: Please note that CrudeCache was developed primarily for personal projects and has not been battle-tested in large-scale production environments. Plus I am still new to Rust, so contributions, suggestions, and feedback are more than welcome.

Features

• Expiration of cached item is evaluated lazily.

• Uses tokio::sync::RwLock for async locking.

• Items are stored in a ShardedMap, which splits the data across multiple shards (HashMaps). This aims to minimize contention points.

Installation

Add this to your Cargo.toml:

[dependencies]
crude_cache = "0.1.0"

Example usage

use crude_cache::CrudeCache;

#[derive(Clone)]
pub struct DataService {
    cache: Arc<CrudeCache>,
    db: Arc<Db>
}

impl DataService {
    pub async fn get_big_data(&self) -> SomeBigType {
        self.cache.get_or_else_update("big_data", Duration::from_secs(60), || self.db.big_data()).await
    }

    pub async fn get_other_data(&self) -> OtherType {
        self.cache.get_or_else_update("other_data", Duration::from_secs(60), || self.db.other_data()).await
    }
}