blocking-queue

library0.0.1jsnpmunverified

A simple blocking FIFO queue and flow control library using Promises, allowing consumers to process tasks with a configurable concurrency limit. Version 0.0.1 is the initial release. It provides a Queue class for push/pop operations and a QueueConsumer to start/stop task processing. Different from full-featured message queues like Bull or Kue, this is lightweight and designed for in-process task orchestration. The library is minimal but functional, suitable for simple sequential or parallel task execution in Node.js.

devops

npm install blocking-queue

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · BLOCKING-QUEUE

blocking-queue

devopsjavascriptv0.0.1

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

Queue

✓ import { Queue } from 'blocking-queue'

✗ const Queue = require('blocking-queue').Queue

Default export is the Queue class; named and default exports are identical.

QueueConsumer

✓ import { QueueConsumer } from 'blocking-queue'

✗ const QueueConsumer = require('blocking-queue').QueueConsumer

Named export from the package.

Queue as default

✓ import Queue from 'blocking-queue'

✗ const Queue = require('blocking-queue')

The default export is the Queue class itself.

Creates a queue, pushes tasks, starts a consumer with concurrency 2, and waits for all tasks to complete.

import { Queue, QueueConsumer } from 'blocking-queue'; const q = new Queue(); q.push('task1'); q.push('task2'); q.push('task3'); q.push('task4'); q.push('task5'); const c = new QueueConsumer(q); c.start(async (task) => { console.log('Processing', task); }, 2); (async () => { await c.end(); console.log('All tasks done'); })();

Debug

Known issues

gotchaQueueConsumer's start method's callback must return a Promise. If using async/await in the callback, ensure it returns the promise explicitly or use async function.

fix

Use an async function: start(async (task) => { ... }) or return a Promise.

affects: 0.0.1

gotchaQueue.pop() returns a Promise that resolves when a task is available. If the queue is empty, it will never resolve until a push occurs.

fix

Ensure tasks are pushed before or concurrently with pop calls.

affects: 0.0.1

gotchaQueueConsumer.end() resolves immediately if the queue is empty and no tasks are in progress. If tasks are still processing, it waits for them to finish.

fix

Call end after all pushes and ensure the consumer is started.

affects: 0.0.1

Errors

Common errors & fixes

TypeError: Queue is not a constructor

Incorrect import: using named import when default was expected, or vice versa.

fix

Use 'import Queue from 'blocking-queue'' or 'const Queue = require('blocking-queue')'.

TypeError: consumer is not a function

Passing a non-function to QueueConsumer.start().

fix

Ensure the first argument to start is a function that returns a Promise.

Upgrade

Version history

0.0.1latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

7 hits · last 30 days

node

Resources

githubhttps://github.com/abehiroshi/node-blocking-queue ↗

packageblocking-queue ↗

homepagehttps://github.com/abehiroshi/node-blocking-queue#readme ↗