DMleadgen
46d973904b
Next.js website for Rocky Mountain Vending company featuring: - Product catalog with Stripe integration - Service areas and parts pages - Admin dashboard with Clerk authentication - SEO optimized pages with JSON-LD structured data Co-authored-by: Cursor <cursoragent@cursor.com>
69 lines
No EOL
2.9 KiB
Text
69 lines
No EOL
2.9 KiB
Text
// Copyright 2024 The Chromium Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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import * as Core from '../core/core.js';
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import { FirstContentfulPaint } from './FirstContentfulPaint.js';
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import { Metric, } from './Metric.js';
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class LargestContentfulPaint extends Metric {
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static get coefficients() {
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return {
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intercept: 0,
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optimistic: 0.5,
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pessimistic: 0.5,
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};
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}
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/**
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* Low priority image nodes are usually offscreen and very unlikely to be the
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* resource that is required for LCP. Our LCP graphs include everything except for these images.
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*/
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static isNotLowPriorityImageNode(node) {
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if (node.type !== 'network') {
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return true;
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}
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const isImage = node.request.resourceType === 'Image';
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const isLowPriority = node.request.priority === 'Low' || node.request.priority === 'VeryLow';
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return !isImage || !isLowPriority;
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}
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static getOptimisticGraph(dependencyGraph, processedNavigation) {
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const lcp = processedNavigation.timestamps.largestContentfulPaint;
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if (!lcp) {
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throw new Core.LanternError('NO_LCP');
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}
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return FirstContentfulPaint.getFirstPaintBasedGraph(dependencyGraph, {
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cutoffTimestamp: lcp,
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treatNodeAsRenderBlocking: LargestContentfulPaint.isNotLowPriorityImageNode,
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});
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}
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static getPessimisticGraph(dependencyGraph, processedNavigation) {
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const lcp = processedNavigation.timestamps.largestContentfulPaint;
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if (!lcp) {
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throw new Core.LanternError('NO_LCP');
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}
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return FirstContentfulPaint.getFirstPaintBasedGraph(dependencyGraph, {
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cutoffTimestamp: lcp,
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treatNodeAsRenderBlocking: _ => true,
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// For pessimistic LCP we'll include *all* layout nodes
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additionalCpuNodesToTreatAsRenderBlocking: node => node.didPerformLayout(),
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});
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}
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static getEstimateFromSimulation(simulationResult) {
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const nodeTimesNotOffscreenImages = Array.from(simulationResult.nodeTimings.entries())
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.filter(entry => LargestContentfulPaint.isNotLowPriorityImageNode(entry[0]))
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.map(entry => entry[1].endTime);
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return {
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timeInMs: Math.max(...nodeTimesNotOffscreenImages),
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nodeTimings: simulationResult.nodeTimings,
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};
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}
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static compute(data, extras) {
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const fcpResult = extras?.fcpResult;
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if (!fcpResult) {
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throw new Core.LanternError('FCP is required to calculate the LCP metric');
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}
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const metricResult = super.compute(data, extras);
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metricResult.timing = Math.max(metricResult.timing, fcpResult.timing);
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return metricResult;
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}
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}
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export { LargestContentfulPaint };
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//# sourceMappingURL=LargestContentfulPaint.js.map |