Files
stack/packages/queue/src/adapters/local.ts
2026-04-02 20:46:11 -05:00

88 lines
2.4 KiB
TypeScript

import { mkdirSync, readFileSync, readdirSync, writeFileSync } from 'node:fs';
import { join } from 'node:path';
import { EventEmitter } from 'node:events';
import type { QueueAdapter, QueueConfig, TaskPayload } from '../types.js';
const DEFAULT_DATA_DIR = '.mosaic/queue';
export function createLocalAdapter(config: QueueConfig): QueueAdapter {
if (config.type !== 'local') {
throw new Error(`Expected config type "local", got "${config.type}"`);
}
const dataDir = config.dataDir ?? DEFAULT_DATA_DIR;
const queues = new Map<string, TaskPayload[]>();
const emitter = new EventEmitter();
mkdirSync(dataDir, { recursive: true });
// Load existing JSON files on startup
for (const file of readdirSync(dataDir)) {
if (!file.endsWith('.json')) continue;
const queueName = file.slice(0, -5);
try {
const raw = readFileSync(join(dataDir, file), 'utf-8');
const items = JSON.parse(raw) as TaskPayload[];
if (Array.isArray(items)) {
queues.set(queueName, items);
}
} catch {
// Ignore corrupt files
}
}
function persist(queueName: string): void {
const items = queues.get(queueName) ?? [];
writeFileSync(join(dataDir, `${queueName}.json`), JSON.stringify(items), 'utf-8');
}
function getQueue(queueName: string): TaskPayload[] {
let q = queues.get(queueName);
if (!q) {
q = [];
queues.set(queueName, q);
}
return q;
}
return {
name: 'local',
async enqueue(queueName: string, payload: TaskPayload): Promise<void> {
getQueue(queueName).push(payload);
persist(queueName);
},
async dequeue(queueName: string): Promise<TaskPayload | null> {
const q = getQueue(queueName);
const item = q.shift() ?? null;
persist(queueName);
return item;
},
async length(queueName: string): Promise<number> {
return getQueue(queueName).length;
},
async publish(channel: string, message: string): Promise<void> {
emitter.emit(channel, message);
},
subscribe(channel: string, handler: (message: string) => void): () => void {
emitter.on(channel, handler);
return () => {
emitter.off(channel, handler);
};
},
async close(): Promise<void> {
for (const queueName of queues.keys()) {
persist(queueName);
}
queues.clear();
emitter.removeAllListeners();
},
};
}