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LockBackend

ash_lock::backend

Trait LockBackend 

Source 
pub trait LockBackend: Send + Sync {
    // Required methods
    fn try_acquire<'life0, 'life1, 'async_trait>(
        &'life0 self,
        key: &'life1 str,
        ttl: Duration,
    ) -> Pin<Box<dyn Future<Output = Result<(u64, Instant)>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait;
    fn try_renew<'life0, 'life1, 'async_trait>(
        &'life0 self,
        key: &'life1 str,
        token: u64,
        ttl: Duration,
    ) -> Pin<Box<dyn Future<Output = Result<Instant>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait;
    fn release<'life0, 'life1, 'async_trait>(
        &'life0 self,
        key: &'life1 str,
        token: u64,
    ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait;

    // Provided method
    fn name(&self) -> &'static str { ... }
}
Expand description

Authoritative storage and arbitration for distributed locks.

The returned Instant on try_acquire / try_renew is the local lease deadline (when this node should consider the lease expired absent a renewal). It is intentionally not serialized across the wire — remote backends translate a TTL into a local deadline on receipt.

Required Methods§

Source

fn try_acquire<'life0, 'life1, 'async_trait>( &'life0 self, key: &'life1 str, ttl: Duration, ) -> Pin<Box<dyn Future<Output = Result<(u64, Instant)>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Attempt to acquire key for ttl. On success returns the fencing token (strictly monotonic per key) and the local lease deadline.

Source

fn try_renew<'life0, 'life1, 'async_trait>( &'life0 self, key: &'life1 str, token: u64, ttl: Duration, ) -> Pin<Box<dyn Future<Output = Result<Instant>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Renew a lease previously acquired with token, extending it by ttl. Returns the new local lease deadline.

Source

fn release<'life0, 'life1, 'async_trait>( &'life0 self, key: &'life1 str, token: u64, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Release a lease. A no-op if token is already stale (someone else owns the key), so releasing an expired guard is harmless.

Provided Methods§

Source

fn name(&self) -> &'static str

Human-readable backend name, used in tracing spans and errors.

Dyn Compatibility§

This trait is dyn compatible.

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

Implementors§