syncguard/firestore/operations/extend.d.ts

Functional TypeScript library for distributed locking across microservices. Prevents race conditions with Redis, PostgreSQL, Firestore, and custom backends. Features automatic lock management, timeout handling, and extensible architecture.

import type { CollectionReference, Firestore } from "@google-cloud/firestore";
import { type ExtendResult, type LockOp } from "../../common/backend.js";
import type { FirestoreConfig } from "../types.js";
/**
 * Creates Firestore extend operation with atomic transaction and authoritative expiresAtMs.
 *
 * **Implementation Pattern:**
 * - Atomic transaction: Query by lockId → verify ownership → update expiresAtMs
 * - TOCTOU protection: All steps within single `runTransaction()` (ADR-003, interface.md)
 * - Ownership verification: Explicit `data.lockId === opts.lockId` check (ADR-003)
 * - Authoritative time: MUST capture `Date.now()` inside transaction (ADR-010)
 * - TTL semantics: Replaces remaining TTL entirely (`nowMs + ttlMs`), not additive
 * - AbortSignal: Manual cancellation checks via `checkAbortedForTransaction()` at strategic points
 *
 * @remarks
 * Omits `.limit(1)` to detect duplicate lockIds (ADR-014). Expired duplicates cleaned,
 * live duplicates fail safely.
 *
 * @see docs/specs/interface.md#extend-operation-requirements - Normative TOCTOU, ownership, and expiresAtMs requirements
 * @see docs/specs/firestore-backend.md#extend-operation-requirements - Firestore transaction pattern
 */
export declare function createExtendOperation(db: Firestore, locksCollection: CollectionReference, config: FirestoreConfig): (opts: LockOp & {
    ttlMs: number;
}) => Promise<ExtendResult>;