beam-cli/dist/analyse/analyse-lighthouse-results.js

A beautifully simple CLI for running Lighthouse audits on a statically generated (SSG) website

import { lighthouseCategoriesArray } from '../lighthouse/categories.js';
/** Gets the total transfered size of a page (in KiB) */
const getPageSizeFromRunResult = (result) => {
    if (!result)
        return 0;
    const { details } = result;
    if (details && details.type === 'table') {
        const total = details.items.find(i => i.resourceType === 'total');
        if (total) {
            return total.transferSize ?? 0;
        }
    }
    return 0;
};
/** Extracts the data that we are interested in
 * from the lighthouse audit results  */
export const analyseLighthouseResults = (runnerResults, generatedHTMLFiles) => {
    const results = {};
    const names = Object.keys(runnerResults);
    for (const name of names) {
        const runResult = runnerResults[name];
        if (!runResult)
            continue;
        const { result, type, url } = runResult;
        const resourceSummary = result.lhr.audits['resource-summary'];
        const sizeDisplay = resourceSummary?.displayValue ?? '';
        const size = getPageSizeFromRunResult(resourceSummary);
        const scores = {};
        for (const cat of lighthouseCategoriesArray) {
            const category = result.lhr.categories[cat];
            if (category) {
                scores[cat] = category.score ?? 0;
            }
        }
        const htmlPath = generatedHTMLFiles[name];
        const summaryResult = {
            name,
            size,
            sizeDisplay,
            mobile: type === 'mobile',
            scores,
            htmlPath,
            url,
        };
        results[name] = summaryResult;
    }
    return {
        data: results,
        date: Date.now().valueOf(),
    };
};