canPrefetchUrl() — astro Function Reference

Architecture documentation for the canPrefetchUrl() function in index.ts from the astro codebase.

Function typescript CoreAstro RenderingEngine calls 1 called by 1

Entity Profile

CoreAstro→ RenderingEngine→ canPrefetchUrl() — astro Function Reference

Dependency Diagram

graph TD
  ea9541b4_bd9d_6d4f_5137_70ec3d7865b1["canPrefetchUrl()"]
  315e53ea_6d34_137c_ce5c_8c89aca90db9["index.ts"]
  ea9541b4_bd9d_6d4f_5137_70ec3d7865b1 -->|defined in| 315e53ea_6d34_137c_ce5c_8c89aca90db9
  1502f987_7806_fcef_2f8e_55d799080686["prefetch()"]
  1502f987_7806_fcef_2f8e_55d799080686 -->|calls| ea9541b4_bd9d_6d4f_5137_70ec3d7865b1
  fa17c239_9e46_24a4_170f_6c1482c21778["isSlowConnection()"]
  ea9541b4_bd9d_6d4f_5137_70ec3d7865b1 -->|calls| fa17c239_9e46_24a4_170f_6c1482c21778
  style ea9541b4_bd9d_6d4f_5137_70ec3d7865b1 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

packages/astro/src/prefetch/index.ts lines 250–265

function canPrefetchUrl(url: string, ignoreSlowConnection: boolean) {
	// Skip prefetch if offline
	if (!navigator.onLine) return false;
	// Skip prefetch if using data saver mode or slow connection
	if (!ignoreSlowConnection && isSlowConnection()) return false;
	// Else check if URL is within the same origin, not the current page, and not already prefetched
	try {
		const urlObj = new URL(url, location.href);
		return (
			location.origin === urlObj.origin &&
			(location.pathname !== urlObj.pathname || location.search !== urlObj.search) &&
			!prefetchedUrls.has(url)
		);
	} catch {}
	return false;
}