Mutate external URLs

content/index.md

@@ -9,3 +9,7 @@ After image
 ![Image](https://theorangeone.net/images/ml7eDl0dfJcNa0gb78bceOAZA2Y=/1/width-1200/header.jpg)
 
 {{ 1 + 2 }}
+
+- [Another page](./other.md)
+- [Something else on the site](/sitemap.xml)
+- [An external site](https://mkdocs.org)

hooks/url-rewrite.py

@@ -0,0 +1,23 @@
+from bs4 import BeautifulSoup
+from urllib.parse import urlsplit, urlunsplit, parse_qs, urlencode
+
+
+def on_page_content(html, page, config, files):
+    soup = BeautifulSoup(html, "html.parser")
+
+    for link in soup.find_all("a", href=True):
+        parsed_url = urlsplit(link["href"])
+
+        if not parsed_url.scheme or not parsed_url.netloc:
+            # Not an external link
+            continue
+
+        # Stick a reference on external URLs
+        parsed_url = parsed_url._replace(query=urlencode({
+            **parse_qs(parsed_url.query),
+            "ref": "mysite.com"
+        }))
+
+        link["href"] = urlunsplit(parsed_url)
+
+    return str(soup)

mkdocs.yml

@@ -21,6 +21,7 @@ hooks:
   - hooks/include-file.py
   - hooks/unsplash.py
   - hooks/exclude-static.py
+  - hooks/url-rewrite.py
 
 markdown_extensions:
   - attr_list
@@ -29,3 +30,7 @@ markdown_extensions:
 
 plugins:
   - search
+
+validation:
+  links:
+    absolute_links: ignore