json-rpc2

library2.0.0jsnpmunverified

JSON-RPC 2.0 server and client library supporting HTTP, TCP, and WebSocket transports for Node.js. Version 2.0.0 (latest) uses native EventEmitter and enforces RFC-compliant request id types (String, Number, or null). Released under MIT license with moderate maintenance cadence. Differentiators include simple API, built-in authentication for TCP sockets, class extension via ES5Class mixins, and WebSocket support out of the box. Requires Node >= 10.

messaging

npm install json-rpc2

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · JSON-RPC2

json-rpc2

messagingjavascriptv2.0.0

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.

Server

✓ import rpc from 'json-rpc2'; const server = rpc.Server.$create(...)

✗ import { Server } from 'json-rpc2'

Package exports a single default object; named imports will be undefined.

Client

✓ const rpc = require('json-rpc2'); const client = rpc.Client.$create(8000, 'localhost');

✗ const { Client } = require('json-rpc2')

CommonJS require returns the default export; destructuring Client directly will yield undefined.

Endpoint

✓ import rpc from 'json-rpc2'; rpc.Endpoint.$include({ ... });

✗ import { Endpoint } from 'json-rpc2'

Use default import then access Endpoint property.

Creates an HTTP+WebSocket JSON-RPC 2.0 server with an 'add' method and a client that calls it.

import rpc from 'json-rpc2'; const server = rpc.Server.$create({ websocket: true, headers: { 'Access-Control-Allow-Origin': '*' } }); function add(args, opt, callback) { callback(null, args[0] + args[1]); } server.expose('add', add); server.listen(8000, 'localhost', () => { console.log('JSON-RPC 2.0 server listening on port 8000'); }); const client = rpc.Client.$create(8000, 'localhost'); client.call('add', [1, 2], (err, result) => { if (err) console.error(err); else console.log('1 + 2 =', result); });

Debug

Known issues

breakingid member now enforces RFC compliance: only String, Number, or null allowed. Non-conforming ids (e.g. objects, arrays) will be rejected.

fix

Ensure all request ids are String, Number, or null.

affects: >=1.0.0

breakingEventEmitter3 replaced with native EventEmitter in version 2.0.0. Code relying on EventEmitter3-specific behavior (e.g., wildcard events) may break.

fix

Do not depend on EventEmitter3-specific APIs; use standard EventEmitter patterns.

affects: >=2.0.0

deprecatedThe package is not actively maintained; last update was in 2019. No security patches for Node.js 14+ vulnerabilities.

fix

Consider migrating to alternatives like 'jayson' or 'json-rpc-2.0'.

affects: *

gotchaDefault export is an object; named imports (like `import { Server } from 'json-rpc2'`) will be undefined.

fix

Use default import: `import rpc from 'json-rpc2'` then access `rpc.Server`.

affects: *

gotcha`Client.$create` expects host as second argument; passing a string with protocol (e.g., 'http://localhost') will fail silently.

fix

Pass only hostname and port separately: `Client.$create(8000, 'localhost')`.

affects: *

Errors

Common errors & fixes

TypeError: rpc.Server is undefined

Using named import instead of default import.

fix

Change to `import rpc from 'json-rpc2'` then use `rpc.Server`.

Error: Invalid id

Request id is not a String, Number, or null.

fix

Ensure id is a string, number, or null as per JSON-RPC 2.0 spec.

TypeError: server.listenRaw is not a function

Using `listenRaw` on an HTTP server; `listenRaw` is only for raw TCP servers created without HTTP options.

fix

Create a raw server with `rpc.Server.$create()` and then call `server.listenRaw(8080, 'localhost')`.

TypeError: Cannot read properties of undefined (reading '$create')

Forgot to import json-rpc2 or imported incorrectly.

fix

Use `const rpc = require('json-rpc2')` or `import rpc from 'json-rpc2'`.

Upgrade

Version history

2.0.0latest on npm

Audit

Dependencies

es5classrequiredRuntime dependency for class inheritance and mixins

Agent activity

13 hits · last 30 days

node

OpenAI (training)

Resources

githubgit://github.com/pocesar/node-jsonrpc2 ↗

packagejson-rpc2 ↗

homepagehttps://github.com/pocesar/node-jsonrpc2#readme ↗