Extract webinspect package for logo discovery

Replace the Google Favicons API with HTML head tag parsing to find higher-quality logos (SVG, apple-touch-icon, large PNG icons, msapplication-TileImage). The new pkg/webinspect package parses a website's DOM tree and is extensible for future resource extraction (footer links, etc.). Signed-off-by: Émile Ré <emile@getprobo.com>
2026-05-11 14:23:19 +04:00
parent 684fadea3e
commit bf8c622bcd
4 changed files with 463 additions and 11 deletions
--- a/pkg/webinspect/logo.go
+++ b/pkg/webinspect/logo.go
@@ -0,0 +1,172 @@
+// Copyright (c) 2026 Probo Inc <hello@getprobo.com>.
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+package webinspect
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+
+	"golang.org/x/net/html"
+)
+
+func FindLogoURL(info *PageInfo) (string, error) {
+	head := findElement(info.Root, "head")
+	if head == nil {
+		return "", fmt.Errorf("cannot find logo: no head element")
+	}
+
+	var (
+		svgIcon        string
+		appleTouchIcon string
+		appleTouchSize int
+		largestIcon    string
+		largestSize    int
+		msTileImage    string
+	)
+
+	for _, n := range findAllIn(head, "link") {
+		rel := strings.ToLower(attrVal(n, "rel"))
+		href := attrVal(n, "href")
+		if href == "" {
+			continue
+		}
+
+		switch {
+		case rel == "icon" && attrVal(n, "type") == "image/svg+xml":
+			svgIcon = href
+		case strings.Contains(rel, "apple-touch-icon"):
+			size := parseSizeAttr(attrVal(n, "sizes"))
+			if appleTouchIcon == "" || size > appleTouchSize {
+				appleTouchIcon = href
+				appleTouchSize = size
+			}
+		case rel == "icon":
+			size := parseSizeAttr(attrVal(n, "sizes"))
+			if largestIcon == "" || size > largestSize {
+				largestIcon = href
+				largestSize = size
+			}
+		}
+	}
+
+	for _, n := range findAllIn(head, "meta") {
+		name := strings.ToLower(attrVal(n, "name"))
+		content := attrVal(n, "content")
+		if name == "msapplication-tileimage" && content != "" {
+			msTileImage = content
+		}
+	}
+
+	candidates := []string{
+		svgIcon,
+		appleTouchIcon,
+		largestIcon,
+		msTileImage,
+	}
+
+	for _, href := range candidates {
+		if href != "" {
+			return info.ResolveHref(href), nil
+		}
+	}
+
+	return "", fmt.Errorf("cannot find logo")
+}
+
+func parseSizeAttr(sizes string) int {
+	if sizes == "" || strings.ToLower(sizes) == "any" {
+		return 0
+	}
+
+	parts := strings.SplitN(sizes, "x", 2)
+	if len(parts) == 0 {
+		return 0
+	}
+
+	w, err := strconv.Atoi(parts[0])
+	if err != nil {
+		return 0
+	}
+
+	return w
+}
+
+func ExtensionForMIME(contentType string) string {
+	ct := strings.ToLower(contentType)
+	if idx := strings.Index(ct, ";"); idx != -1 {
+		ct = ct[:idx]
+	}
+	ct = strings.TrimSpace(ct)
+
+	switch ct {
+	case "image/svg+xml":
+		return ".svg"
+	case "image/png":
+		return ".png"
+	case "image/jpeg":
+		return ".jpg"
+	case "image/gif":
+		return ".gif"
+	case "image/webp":
+		return ".webp"
+	case "image/x-icon", "image/vnd.microsoft.icon":
+		return ".ico"
+	default:
+		return ".png"
+	}
+}
+
+// HeadLinks returns all <link> nodes from <head> whose rel attribute
+// contains the given value (case-insensitive partial match).
+func (p *PageInfo) HeadLinks(rel string) []*html.Node {
+	head := findElement(p.Root, "head")
+	if head == nil {
+		return nil
+	}
+
+	rel = strings.ToLower(rel)
+	var matches []*html.Node
+
+	for _, n := range findAllIn(head, "link") {
+		if strings.Contains(strings.ToLower(attrVal(n, "rel")), rel) {
+			matches = append(matches, n)
+		}
+	}
+
+	return matches
+}
+
+// HeadMeta returns the content attribute of the first <meta> tag in <head>
+// whose name attribute matches (case-insensitive).
+func (p *PageInfo) HeadMeta(name string) (string, bool) {
+	head := findElement(p.Root, "head")
+	if head == nil {
+		return "", false
+	}
+
+	name = strings.ToLower(name)
+
+	for _, n := range findAllIn(head, "meta") {
+		if strings.EqualFold(attrVal(n, "name"), name) {
+			content := attrVal(n, "content")
+			if content != "" {
+				return content, true
+			}
+		}
+	}
+
+	return "", false
+}