collectBrokenExternalLinks

Validates the deduplicated external URLs over the network through a bounded concurrency pool.

A network failure, an HTTP 429 and an HTTP 5xx are retried with an exponential, jittered backoff that honors Retry-After (see ExternalLinkRetryOptions); any other status, a 404 included, is final at once. Probes of one host are also capped at CollectBrokenExternalLinksOptions.perHostConcurrency, and a probe of another host is started while one host is at its cap.

Import:

import { collectBrokenExternalLinks } from '@mnaoumov/typescript-dev-toolkit/docs-site/link-check';

Signature:

function collectBrokenExternalLinks(targets: Map<string, string>, fetchUrlStatus: (url: string) => Promise<number | ExternalLinkProbeResult>, concurrency: number, options: CollectBrokenExternalLinksOptions): Promise<BrokenLink[]>

Parameters:

Parameter	Type	Description
targets	Map<string, string>	The unique external URL → referencing page map from collectExternalTargets.
fetchUrlStatus	(url: string) => Promise<number | ExternalLinkProbeResult>	Injected probe returning the HTTP status for a URL (0 for a network failure), or an ExternalLinkProbeResult that also carries the server’s Retry-After.
concurrency	number	The maximum number of in-flight probes.
options	CollectBrokenExternalLinksOptions	The per-host cap and the retry policy.

Returns: Promise<BrokenLink[]> — Every external URL that did not return HTTP 200, in the map’s iteration order.

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Links to this page:

• CollectBrokenExternalLinksOptions
• ExternalLinkRetryOptions