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>
48 lines
No EOL
2.3 KiB
Text
48 lines
No EOL
2.3 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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// A DNS lookup will usually take ~1-2 roundtrips of connection latency plus the extra DNS routing time.
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// Example: https://www.webpagetest.org/result/180703_3A_e33ec79747c002ed4d7bcbfc81462203/1/details/#waterfall_view_step1
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// Example: https://www.webpagetest.org/result/180707_1M_89673eb633b5d98386de95dfcf9b33d5/1/details/#waterfall_view_step1
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// DNS is highly variable though, many times it's a little more than 1, but can easily be 4-5x RTT.
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// We'll use 2 since it seems to give the most accurate results on average, but this can be tweaked.
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const DNS_RESOLUTION_RTT_MULTIPLIER = 2;
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class DNSCache {
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static rttMultiplier = DNS_RESOLUTION_RTT_MULTIPLIER;
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rtt;
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resolvedDomainNames;
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constructor({ rtt }) {
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this.rtt = rtt;
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this.resolvedDomainNames = new Map();
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}
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getTimeUntilResolution(request, options) {
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const { requestedAt = 0, shouldUpdateCache = false } = options || {};
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const domain = request.parsedURL.host;
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const cacheEntry = this.resolvedDomainNames.get(domain);
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let timeUntilResolved = this.rtt * DNSCache.rttMultiplier;
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if (cacheEntry) {
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const timeUntilCachedIsResolved = Math.max(cacheEntry.resolvedAt - requestedAt, 0);
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timeUntilResolved = Math.min(timeUntilCachedIsResolved, timeUntilResolved);
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}
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const resolvedAt = requestedAt + timeUntilResolved;
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if (shouldUpdateCache) {
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this.updateCacheResolvedAtIfNeeded(request, resolvedAt);
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}
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return timeUntilResolved;
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}
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updateCacheResolvedAtIfNeeded(request, resolvedAt) {
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const domain = request.parsedURL.host;
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const cacheEntry = this.resolvedDomainNames.get(domain) || { resolvedAt };
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cacheEntry.resolvedAt = Math.min(cacheEntry.resolvedAt, resolvedAt);
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this.resolvedDomainNames.set(domain, cacheEntry);
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}
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/**
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* Forcefully sets the DNS resolution time for a request.
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* Useful for testing and alternate execution simulations.
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*/
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setResolvedAt(domain, resolvedAt) {
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this.resolvedDomainNames.set(domain, { resolvedAt });
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}
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}
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export { DNSCache };
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//# sourceMappingURL=DNSCache.js.map |