networkInfo

Wrapper around navigator.connection (Network Information API).

Module networkInfo | Source packages/front/fw/src/dom/sensors/networkInfo.js | Deps none | Worker-safe no

Variable support: Network Information API is in draft / origin-trial depending on the browser. Chrome/Android supports most fields; Safari does not. Test isSupported() and use effectiveType as the most stable field.

Resolve

const networkInfo = runtime.resolve('networkInfo');
// Returns: { isSupported, current, watch }

API

Type NetworkInfo

{
    downlink: number,                              // estimated Mbit/s (downlink)
    downlinkMax: number | undefined,               // theoretical maximum (physical type)
    effectiveType: 'slow-2g' | '2g' | '3g' | '4g',  // most stable field
    rtt: number,                                   // estimated latency ms (rounded to 25ms)
    saveData: boolean,                             // data saver mode active
    type: string | undefined,                      // 'wifi' | 'cellular' | 'ethernet' | ...
}

Examples

const networkInfo = runtime.resolve('networkInfo');

if (networkInfo.isSupported()) {
    const info = networkInfo.current();
    if (info.effectiveType === 'slow-2g' || info.saveData) {
        loadLowResImages();
    }
}

// Watch for changes
const stop = networkInfo.watch(info => {
    console.log('Connection:', info.effectiveType, info.downlink, 'Mbit/s');
});

Notes

• effectiveType is the most stable cross-browser field for adapting the UI.
• current() is synchronous (unlike battery.current() which is async).
• The change event fires on every connection change (wifi → 4g, etc.).

See also

• battery — battery state
• network — online/offline detection (more reliable)