class DurableObjectLock
Since 0.2.0

A distributed lock backed by one Durable Object per key.

Structurally satisfies scheduler-plugin's IDistributedLock without importing it — that interface is internal to its own package, and AI_GUIDELINES §2.2/§3.3 forbid a plugin importing another plugin. The application hands an instance to SchedulerPlugin, the same wiring KvSessionStore uses for SessionPlugin, because that option is read at plugin construction before any application exists.

Correctness comes from the platform rather than from an algorithm: a Durable Object executes one request at a time, so the read-compare-write inside DistributedLockObjectCore is atomic with no transaction and no Redlock-style quorum.

Examples

Example 1

import { env } from 'cloudflare:workers';
import { DurableObjectLock } from '@setu-ts/cloudflare-plugin';
import { SchedulerPlugin } from '@setu-ts/scheduler-plugin';

const lock = new DurableObjectLock(env.LOCKS as IDurableObjectNamespace, {
  runtime,
  keyPrefix: 'reports:',
});

// `enabled: true` is NOT needed: resolveLock consults `lock` before it
// consults `enabled`, so an injected lock always wins.
app.register(SchedulerPlugin({ distributedLock: { lock } }));

Constructors

DurableObjectLock(
)
Parameters

The Durable Object namespace binding

The runtime services, and optional key namespacing

Methods

acquire(
key: string,
ttlMs: number
): Promise<string | null>

Attempts to acquire the lock.

release(
key: string,
token: string
): Promise<void>

Releases a previously acquired lock.

A token that does not match the current holder is ignored by the object, so a caller whose claim already expired cannot release its successor's.

Usage

import { DurableObjectLock } from "cloudflare-plugin/src/index.ts";