Link Extraction

Standalone link extraction API that can extract all link resources from HTML and group them by type.

Key difference from Extract

ExtractAllLinks does not apply HTML sanitization (EnableSanitization has no effect here), so resource links inside tags such as <script src>, <iframe>, <link>, and <embed> are extracted in full. This lets those resource links be enumerated — in the Extract path they are normally removed during sanitization.

Result ordering and deduplication

ExtractAllLinks returns results sorted by URL ascending and deduplicated by URL. Calling it repeatedly on the same input therefore yields identical output (since v1.4.2), which eases result comparison, cache reuse, and reproducible downstream processing. When the same URL appears in multiple tags, only one record is kept.

Package Functions

func ExtractAllLinks(htmlBytes []byte, cfg ...Config) ([]LinkResource, error)
func ExtractAllLinksFromFile(filePath string, cfg ...Config) ([]LinkResource, error)
func ExtractAllLinksWithContext(ctx context.Context, htmlBytes []byte, cfg ...Config) ([]LinkResource, error)
func ExtractAllLinksFromFileWithContext(ctx context.Context, filePath string, cfg ...Config) ([]LinkResource, error)

Processor Methods

func (p *Processor) ExtractAllLinks(htmlBytes []byte) ([]LinkResource, error)
func (p *Processor) ExtractAllLinksFromFile(filePath string) ([]LinkResource, error)
func (p *Processor) ExtractAllLinksWithContext(ctx context.Context, htmlBytes []byte) ([]LinkResource, error)
func (p *Processor) ExtractAllLinksFromFileWithContext(ctx context.Context, filePath string) ([]LinkResource, error)

Grouping Utility

GroupLinksByType

Group links by their type.

func GroupLinksByType(links []LinkResource) map[string][]LinkResource

links, _ := html.ExtractAllLinks(data)
groups := html.GroupLinksByType(links)

for typ, items := range groups {
    fmt.Printf("Type %s: %d items\n", typ, len(items))
}

LinkResource

type LinkResource struct {
    URL   string // Link URL
    Title string // Link title
    Type  string // Link type (link, image, video, audio, media, css, js, icon)
}

Configuration

Link extraction behavior is controlled via Config link filtering fields:

cfg := html.DefaultConfig()
cfg.IncludeImages = true
cfg.IncludeCSS = true
cfg.IncludeJS = true
cfg.IncludeExternalLinks = true
cfg.ResolveRelativeURLs = true
cfg.BaseURL = "https://example.com"

TIP

When ResolveRelativeURLs=true and BaseURL is empty, the library automatically derives BaseURL from the HTML document itself, trying each of the following in priority order and returning the first match:

1. the <base href> tag;
2. the content of <meta property="og:url"> or <meta property="canonical">;
3. <link rel="canonical" href>;
4. the first absolute URL found in the document (extracting the base from its href/src).

Setting BaseURL explicitly skips auto-detection and uses the value provided by the caller.