Struct Middleware 

pub struct Middleware(/* private fields */);

A condition checked before a job’s attempt; see Job::middleware.

use renox::queue::Middleware;
impl Job for SyncStock {
    const NAME: &'static str = "sync-stock";

    fn middleware(&self) -> Vec<Middleware> {
        vec![
            // One sync per shop at a time; others wait 10 s and try again.
            Middleware::without_overlapping(format!("shop:{}", self.shop_id))
                .release_after(Duration::from_secs(10)),
            // The supplier's API allows 60 calls a minute.
            Middleware::rate_limited("supplier-api", 60, Duration::from_secs(60)),
        ]
    }

    async fn handle(self, _ctx: JobContext) -> Result { Ok(()) }
}

Both use the cache (CACHE_STORE): with memory, they hold within one process; use database when several processes run workers.

Implementations

impl Middleware

pub fn without_overlapping(key: impl Into<String>) -> Self

One job with this key at a time; others are put back for 5 seconds (see Middleware::release_after).

pub fn rate_limited(key: impl Into<String>, max: u32, per: Duration) -> Self

At most max attempts with this key per per (a fixed window); the rest are put back until the window ends.

pub fn release_after(self, wait: Duration) -> Self

How long a job waits before trying again when it would overlap.

Trait Implementations

impl Clone for Middleware

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Middleware

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.