Locks — `nestrs-locks` - Nestrs

nestrs-locks provides lease-based exclusivity (in-memory or Redis). Use it for schedule single-runner jobs, leader election light, and critical sections that must not overlap across processes.

Install

[dependencies]
nestrs = { version = "1.7.1", features = ["locks"] }
# Redis:
nestrs-locks = { version = "1.7.1", features = ["cache-redis"] }

Usage

use nestrs::locks::{LocksModule, LocksOptions, LocksService};
use std::sync::Arc;

#[module(imports = [LocksModule::register(LocksOptions::default())], providers = [Jobs])]
struct AppModule;

#[injectable]
struct Jobs {
    locks: Arc<LocksService>,
}

impl Jobs {
    async fn run_nightly(&self) {
        let Some(guard) = self.locks.try_acquire("cron:nightly").await else {
            return; // another instance holds the lease
        };
        // … work …
        guard.release().await;
    }

    async fn with_helper(&self) {
        let _ = self
            .locks
            .with_lock("invoice:42", || async {
                // exclusive work
            })
            .await;
    }
}

Options

Field	Default	Role
`store`	in-memory	`SharedLockStore`
`default_ttl`	30s	Lease lifetime; must cover worst-case work or extend

Pick TTL shorter than the duplicate work you can tolerate after a crash, but long enough that healthy work does not lose the lease mid-flight. Extend on long steps.

Schedule single-runner

Combine with ScheduleModule (schedule feature): acquire a named lock at the start of #[cron] / #[interval] handlers so only one replica runs the job.

See also

Workflows (often paired with locks)
API reference