Description
Rustdoc needs redirects in the output it produces, for example when an item is publicly re-exported. Currently redirects are implemented by generating HTML pages like this:
<!DOCTYPE html>
<html lang="en">
<head>
<meta http-equiv="refresh" content="0;URL=../../example/struct.Public.html">
</head>
<body>
<p>Redirecting to <a href="../../example/struct.Public.html">../../example/struct.Public.html</a>...</p>
<script>location.replace("../../example/struct.Public.html" + location.search + location.hash);</script>
</body>
</html>The problem with this approach is that the user sees the HTML page for a brief moment of time while the redirect is performed, which is not really a great UX. The HTML page also includes an inline <script> tag, which makes implementing content security policies harder. Still, this is the only way to implement redirects when the user visits documentation from the local filesystem or a static web server.
Dynamic applications like docs.rs can provide a better UX than this though, by performing the redirects on the server side. This issue proposes a new -Z generate-redirect-map unstable flag, which stops generating HTML redirects and instead produces a redirect-map.json file at the top level containing all the redirects needed by rustdoc:
{
"example/private/struct.Public.html": "example/struct.Public.html"
}