bandwidth

Download/upload speed, latency, and jitter from a live measurement, as async global atoms.

Runs a measurement

Reading a measured atom triggers a download/upload test on first subscribe. Call invalidateMeasurement() to discard the result and re-run.

Install

bun add @valdres/bandwidth

Live example

▶ Live example: https://valdres.dev/react/plugins/bandwidth

Usage

import { Suspense } from "react"
import { useValue } from "valdres-react"
import { downloadSpeedAtom, latencyAtom } from "@valdres/bandwidth"

function Speed() {
    const download = useValue(downloadSpeedAtom)
    const latency = useValue(latencyAtom)
    return <span>{download.toFixed(1)} Mbps · {latency.toFixed(0)} ms</span>
}

// The measured atoms suspend until the test resolves
export function App() {
    return (
        <Suspense fallback="Measuring…">
            <Speed />
        </Suspense>
    )
}

Exports

| Export | Kind | Type | | ------------------------- | ----------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------- | | downloadSpeedAtom | atom (read-only, async) | number — Mbps | | uploadSpeedAtom | atom (read-only, async) | number — Mbps | | latencyAtom | atom (read-only, async) | number — ms | | jitterAtom | atom (read-only, async) | number — ms | | measurementStatusAtom | atom (settable) | MeasurementStatus | | lastMeasurementAtom | atom (settable) | number \| null — timestamp | | invalidateOnAtom | atom (settable) | GlobalAtom<unknown>[] | | measureBandwidth | util fn | (options?: MeasureBandwidthOptions) => Promise<BandwidthResult> | | invalidateMeasurement | util fn | () => void | | MeasurementStatus | type | "idle" \| "measuring-latency" \| "measuring-download" \| "measuring-upload" \| "complete" \| "error" | | BandwidthResult | type | { downloadMbps, uploadMbps, latencyMs, jitterMs, timestamp: number } | | MeasureBandwidthOptions | type | { latencySamples?, maxDurationMs?, minDurationMs?, warmupMs?, startStreams?, maxStreams?, stabilityThreshold?: number; signal?: AbortSignal; fresh?: boolean } |

Cross-framework

One in-flight measurement is shared across every store and framework. invalidateMeasurement() clears the result and, if anything is subscribed, kicks off a fresh run.

Full documentation: https://valdres.dev/react/plugins/bandwidth