Registry / http-networking / lightstreamer-client-web

lightstreamer-client-web

library9.2.3jsnpmunverified

Lightstreamer Client Web SDK (v9.2.3, stable) enables real-time bidirectional communication with a Lightstreamer server from web browsers. It supports WebSocket fallback options and delivers streaming data updates with low latency. Key differentiators: multiple module formats (UMD, CommonJS, ES Module) for varying bundler compatibility; includes core, full, and MPN builds; provides TypeScript definitions. Maintained by Lightstreamer with frequent releases. Ideal for financial tickers, live dashboards, and collaborative applications.

http-networking

npm install lightstreamer-client-web

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · LIGHTSTREAMER-CLIE

lightstreamer-client-web

http-networkingjavascriptv9.2.3

Install

—

Import

—

Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

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

LightstreamerClient

✓ import { LightstreamerClient } from 'lightstreamer-client-web';

✗ const LightstreamerClient = require('lightstreamer-client-web');

ESM import for modern bundlers; requires using the ES module build.

Subscription

✓ import { Subscription } from 'lightstreamer-client-web';

✗ import Subscription from 'lightstreamer-client-web';

Subscription is a named export, not default.

ConsoleLogger

✓ import { ConsoleLogger } from 'lightstreamer-client-web';

✗ import { ConsoleLogger } from 'lightstreamer-client-web/lightstreamer.esm.js';

Import from the package root; bundlers resolve the correct file.

Connects to Lightstreamer demo server, subscribes to three items with MERGE mode, and logs stock updates to console.

import { LightstreamerClient, Subscription } from 'lightstreamer-client-web'; import { ConsoleLogger } from 'lightstreamer-client-web'; const client = new LightstreamerClient('http://push.lightstreamer.com', 'DEMO'); client.addListener({ onListenEnd: () => console.log('Disconnected'), onServerError: (errorCode, errorMessage) => console.error(errorCode, errorMessage), onStatusChange: (newStatus) => console.log('Status:', newStatus) }); const sub = new Subscription('MERGE', ['item1','item2','item3'], ['stock_name','last_price']); sub.setDataAdapter('QUOTE_ADAPTER'); sub.setRequestedSnapshot('yes'); sub.addListener({ onItemUpdate: (obj) => { console.log(obj.getValue('stock_name') + ': ' + obj.getValue('last_price')); }, onSubscriptionError: (code, msg) => console.error('Subscription error', code, msg) }); client.connect(); client.subscribe(sub);

Debug

Known issues

gotchaWhen using the UMD build with a script tag, the library is placed under the namespace specified by the data-lightstreamer-ns attribute. If omitted, it pollutes the global window object.

fix

Add data-lightstreamer-ns='Ls' to the script tag to create a global Ls object, or omit to inject directly into window.

affects: >=9.0

gotchaThe full library contains Widgets and Mobile Push Notifications modules which are not available in Web Workers. Using the full build in a worker throws errors.

fix

Use the core build instead (e.g., importScripts('path/to/lightstreamer-core.js')).

affects: >=9.0

gotchaCommonJS and ES Module builds are not minified; bundlers are expected to handle minification. Attempting to use them directly in a browser without bundling will fail.

fix

Use the UMD minified build for direct browser usage, or configure your bundler to minify the output.

affects: >=9.0

deprecatedThe 'Subscription' constructor signature with mode, items, fields is still supported but the recommended pattern is to use the options object.

fix

Use new Subscription({mode:'MERGE', items:['item1'], fields:['field1']}) instead of positional arguments.

affects: >=9.0

Errors

Common errors & fixes

Uncaught ReferenceError: Ls is not defined

The UMD script tag is missing the data-lightstreamer-ns attribute, but code references Ls.LightstreamerClient.

fix

Add data-lightstreamer-ns='Ls' to the script tag, or change code to use window.LightstreamerClient directly.

Cannot use 'import' statement outside a module

The library's ES module build is loaded via a script tag without type='module' or in a non-module context.

fix

Use the UMD build with a script tag, or add type='module' to the script tag and use an importmap or bundler.

Error: No client found for session

Calling subscribe before connect() or after disconnect() without a valid session.

fix

Ensure you call client.connect() before client.subscribe(sub), and check client status via client.addListener({onStatusChange}).

Upgrade

Version history

9.2.3latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

2 hits · last 30 days

node

Resources

githubhttps://github.com/Lightstreamer/Lightstreamer-lib-client-haxe ↗

packagehttps://www.npmjs.com/package/lightstreamer-client-web ↗

homepagehttps://lightstreamer.com ↗