pws

library7.0.0jsnpmunverified

PWS (v7.0.0) is a drop-in replacement for the browser WebSocket API that adds automatic reconnection with exponential backoff (max 5 min) and configurable ping timeout to detect half-open connections. It works in both browsers and Node.js (requires the 'ws' library). Unlike alternatives like reconnecting-websocket, PWS closely mimics the standard WebSocket interface and triggers reconnect on browser 'online' events. Released by porsager with regular updates.

communication

npm install pws

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · PWS

pws

communicationjavascriptv7.0.0

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.

PersistentWebSocket

✓ import { PersistentWebSocket } from 'pws'

✗ const PersistentWebSocket = require('pws').PersistentWebSocket

Default export is the PersistentWebSocket class. In CommonJS, use require('pws') directly.

default (class)

✓ import PWS from 'pws'

✗ const pws = require('pws').default

PWS is a default export. In CommonJS, require('pws') returns the class directly.

PWS (factory function for Node)

✓ const PWS = require('pws'); const pws = PWS(url, WebSocket);

✗ const pws = new PWS(url, WebSocket);

In Node.js, PWS is a factory function that takes a WebSocket constructor as the second argument. Do not use 'new'.

Shows browser usage with PersistentWebSocket class, including onopen, onmessage, and onerror events.

import { PersistentWebSocket } from 'pws'; const url = process.env.WS_URL ?? 'wss://echo.websocket.org'; const ws = new PersistentWebSocket(url, { pingTimeout: 30000, }); ws.onopen = () => { console.log('Connected'); ws.send('Hello'); }; ws.onmessage = (event) => { console.log('Received:', event.data); }; ws.onerror = (error) => { console.error('Error:', error); };

Debug

Known issues

breakingIn Node.js, PWS is a factory function, not a constructor. Using 'new' will throw an error.

fix

Use PWS(url, WebSocket) without 'new'.

affects: >=1.0.0

gotchaThe default export is the class itself, not a named export. In TypeScript, only 'PersistentWebSocket' is exported as named.

fix

Use import PWS from 'pws' or import { PersistentWebSocket } from 'pws'.

affects: >=7.0.0

gotchaThe options object (url, WebSocket) is specified as second argument in the constructor, not as an options bag in the first argument.

fix

Pass options as second argument: new PersistentWebSocket(url, { pingTimeout: 30000 }).

affects: >=1.0.0

deprecatedThe 'pws' package has been deprecated in favor of 'pws' v7? Check changelog. Some older versions may have different APIs.

fix

Upgrade to latest version and review API changes.

affects: <7.0.0

Errors

Common errors & fixes

TypeError: PWS is not a constructor

Using 'new PWS(url, WebSocket)' in Node.js, but PWS is a factory function.

fix

Remove 'new': const ws = PWS(url, WebSocket);

Cannot find module 'pws'

Missing npm install or typo in import.

fix

Run 'npm install pws' or check spelling.

Uncaught ReferenceError: PersistentWebSocket is not defined

Trying to use PersistentWebSocket without importing it.

fix

Add import: import { PersistentWebSocket } from 'pws';

TypeError: WebSocket is not a constructor

In Node.js, the 'ws' package is not installed or not passed correctly.

fix

Install 'ws' package: npm install ws, then require it and pass as second argument to PWS factory.

Upgrade

Version history

7.0.0latest on npm

Audit

Dependencies

wsoptionalRequired for Node.js usage; PWS expects a compatible WebSocket implementation.

Agent activity

20 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/porsager/pws ↗

packagepws ↗

homepagehttps://github.com/porsager/pws#readme ↗