feat: Add redirect tracking and reporting for link checker

linkchecker.go

@@ -23,10 +23,16 @@ func NewLinkChecker() *LinkChecker {
 	}
 }
 
+type RedirectInfo struct {
+	FromURL string
+	ToURL   string
+}
+
 type BrokenLink struct {
 	URL        string
 	StatusCode int
 	Error      string
+	Redirect   *RedirectInfo
 }
 
 func (lc *LinkChecker) normalizeURL(rawURL string) string {
@@ -81,7 +87,8 @@ func (lc *LinkChecker) checkLinksRecursive(pageURL string, brokenLinks []BrokenL
 	}
 
 	for _, link := range links {
-		if status, err := lc.isLinkValid(link); status >= 400 || err != nil {
+		status, redirect, err := lc.isLinkValid(link)
+		if status >= 400 || err != nil {
 			broken := BrokenLink{URL: link}
 			if err != nil {
 				broken.Error = err.Error()
@@ -89,6 +96,13 @@ func (lc *LinkChecker) checkLinksRecursive(pageURL string, brokenLinks []BrokenL
 				broken.StatusCode = status
 			}
 			brokenLinks = append(brokenLinks, broken)
+		} else if redirect != nil {
+			broken := BrokenLink{
+				URL:      link,
+				StatusCode: status,
+				Redirect: redirect,
+			}
+			brokenLinks = append(brokenLinks, broken)
 		}
 		
 		// Recursively check links from the same domain
@@ -154,12 +168,35 @@ func (lc *LinkChecker) getLinks(pageURL string) ([]string, error) {
 	return links, nil
 }
 
-func (lc *LinkChecker) isLinkValid(link string) (int, error) {
+func (lc *LinkChecker) isLinkValid(link string) (int, *RedirectInfo, error) {
-	resp, err := lc.client.Get(link)
+	client := &http.Client{
+		CheckRedirect: func(req *http.Request, via []*http.Request) error {
+			return http.ErrUseLastResponse
+		},
+	}
+
+	resp, err := client.Get(link)
 	if err != nil {
-		return 0, err
+		return 0, nil, err
 	}
 	defer resp.Body.Close()
 
-	return resp.StatusCode, nil
+	if resp.StatusCode >= 300 && resp.StatusCode < 400 {
+		location := resp.Header.Get("Location")
+		if location != "" {
+			redirectURL := location
+			if !strings.HasPrefix(location, "http") {
+				baseURL, _ := url.Parse(link)
+				if relative, err := baseURL.Parse(location); err == nil {
+					redirectURL = relative.String()
+				}
+			}
+			return resp.StatusCode, &RedirectInfo{
+				FromURL: link,
+				ToURL:   redirectURL,
+			}, nil
+		}
+	}
+
+	return resp.StatusCode, nil, nil
 }

main.go

@@ -27,10 +27,12 @@ func main() {
 		return
 	}
 
-	fmt.Printf("Found %d broken links:\n", len(brokenLinks))
+	fmt.Printf("Found %d issues:\n", len(brokenLinks))
 	for _, link := range brokenLinks {
 		if link.Error != "" {
 			fmt.Printf("- %s (Error: %s)\n", link.URL, link.Error)
+		} else if link.Redirect != nil {
+			fmt.Printf("- %s (Redirect %d -> %s)\n", link.URL, link.StatusCode, link.Redirect.ToURL)
 		} else {
 			fmt.Printf("- %s (Status: %d)\n", link.URL, link.StatusCode)
 		}