bazzar/crates/cache-adapter/src/lib.rs
2023-06-03 13:31:57 +02:00

69 lines
1.5 KiB
Rust

#![feature(box_into_inner)]
use std::borrow::Cow;
use async_trait::async_trait;
pub use config::PluginConfig;
use tracing::warn;
#[derive(Debug, thiserror::Error)]
pub enum Error {
#[error("Unable to connect")]
Connect,
#[error("Entry is invalid")]
InvalidEntry,
#[error("Can't invalidate keys {0:?}")]
Invalidate(Vec<String>),
#[error("Failed to parse config")]
InvalidConfig,
}
pub type CResult<T> = Result<T, Error>;
#[derive(Debug)]
pub enum InvalidatePattern<'s> {
StartsWith(Cow<'s, str>),
EndsWith(Cow<'s, str>),
Contains(Cow<'s, str>),
Const(Cow<'s, str>),
}
pub struct CacheObject(pub Option<Vec<u8>>);
impl CacheObject {
pub fn into_inner<T>(self) -> CResult<Option<T>>
where
T: serde::de::DeserializeOwned,
{
let Some(data) = self.0 else {
return Ok(None)
};
bincode::deserialize(&data)
.map_err(|e| {
warn!("Malformed cache entry: {e}");
Error::InvalidEntry
})
.map(Some)
}
}
#[async_trait]
pub trait CacheAdapter {
async fn new(config: PluginConfig) -> CResult<Self>
where
Self: Sized;
async fn read(&self, key: &str) -> CResult<CacheObject>;
async fn set(
&mut self,
key: &str,
data: &[u8],
expires_in: Option<std::time::Duration>,
) -> CResult<()>;
async fn invalidate(&mut self, pattern: InvalidatePattern<'_>) -> CResult<u64>;
async fn clear(&mut self) -> CResult<u64>;
}