wspr

library2.2.0jsnpmunverified

WebSocket proxy that forwards HTTP POST requests to connected WebSocket clients. Version 2.2.0 is the latest stable release. Useful for testing and mocking WebSocket integrations by converting simple HTTP POST calls into WebSocket broadcasts. Lightweight, zero-config CLI tool with optional SSL support. Differentiates from full WebSocket mocking libraries by focusing on the HTTP-to-WebSocket bridge pattern with minimal setup.

testing

npm install wspr

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · WSPR

wspr

testingjavascriptv2.2.0

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.

wspr CLI

✓ npm i -g wspr

✗ npm install wspr --save-dev

wspr is designed as a global CLI tool. Local install will not expose the 'wspr' command unless added to package.json scripts.

Installs wspr globally, starts the proxy, and demonstrates broadcasting a JSON message via HTTP POST to all connected WebSocket clients.

# Install globally npm i -g wspr # Start the proxy (default ports: WS=3005, HTTP=3006) wspr # In another terminal, connect a WebSocket client (e.g., wscat) # wscat -c ws://localhost:3005 # Send an HTTP POST to broadcast to all WebSocket clients curl -d "{\"hello\": \"world\"}" -X POST http://localhost:3006 # For secure WebSocket (wss), provide cert and key: wspr --cert=./localhost.crt --key=./localhost.key

Debug

Known issues

gotchawspr binds to localhost by default. It will not accept connections from external hosts unless configured otherwise.

fix

Modify the source code or use a reverse proxy to bind to 0.0.0.0 if remote access is required.

affects: >=0.0.0

gotchaThe HTTP proxy endpoint does not support GET requests; only POST. Using GET will result in an error or no broadcast.

fix

Use POST method with a request body (string or JSON) to the HTTP endpoint.

affects: >=0.0.0

deprecatedSSL setup instructions reference self-signed certificates. Modern browsers may reject self-signed certs for WebSocket connections.

fix

Use a trusted certificate authority or use wss with valid certificates.

affects: >=0.0.0

Errors

Common errors & fixes

Command 'wspr' not found

wspr is not installed globally or not in PATH.

fix

Run 'npm i -g wspr' and ensure npm global binaries are in your PATH.

Error: listen EADDRINUSE :::3005

Port 3005 is already in use by another process.

fix

Kill the process on that port (e.g., lsof -ti:3005 | xargs kill) or modify wspr source to use a different port.

WebSocket connection to 'ws://localhost:3005' failed: Error in connection establishment: net::ERR_CONNECTION_REFUSED

wspr server is not running or firewall is blocking the connection.

fix

Start wspr in a terminal. Ensure no firewall rules block the port.

Upgrade

Version history

2.2.0latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

15 hits · last 30 days

node

Resources

githubhttps://github.com/zaqqaz/wspr ↗

packagewspr ↗

homepagehttps://github.com/zaqqaz/wspr#readme ↗