Function getCoreWebVitals

apps/page-timing/content-script.js:130–163

()

    // 获取核心Web指标
    function getCoreWebVitals() {
        return new Promise(resolve => {
            let webVitals = {};
            
            // LCP (Largest Contentful Paint)
            new PerformanceObserver((entryList) => {
                const entries = entryList.getEntries();
                const lastEntry = entries[entries.length - 1];
                webVitals.lcp = lastEntry.renderTime || lastEntry.loadTime;
            }).observe({entryTypes: ['largest-contentful-paint']});

            // FID (First Input Delay)
            new PerformanceObserver((entryList) => {
                const firstInput = entryList.getEntries()[0];
                if (firstInput) {
                    webVitals.fid = firstInput.processingTime;
                    webVitals.firstInputTime = firstInput.startTime;
                }
            }).observe({entryTypes: ['first-input']});

            // CLS (Cumulative Layout Shift)
            let clsValue = 0;
            new PerformanceObserver((entryList) => {
                for (const entry of entryList.getEntries()) {
                    if (!entry.hadRecentInput) {
                        clsValue += entry.value;
                    }
                }
                webVitals.cls = clsValue;
            }).observe({entryTypes: ['layout-shift']});

            setTimeout(() => resolve(webVitals), 3000);
        });
    }

    // 获取性能指标
    function getPerformanceMetrics() {