php - Diggbar modrewrite- How do they pass URLs through modrewrite?

Question

With the new Diggbar, you can put http://digg.com in front of any URL that you are currently at and it will create a Digg short URL. I am only assuming they do this by modrewrite (though I am not sure since I am new at this all).

How is this done? It seems to me when I try this with a website I am working on, it bombs out.

I want to be able to do the following:

http://example.com/http://stackoverflow.com/question/ask

and have a modrewrite that will allow this to go to

http://example.com/index.php?url=http://stackoverflow.com/question/ask

But when I use this modrewrite:

RewriteEngine on
RewriteRule ^([A-Za-z0-9]+)$ /message.php?id=$1 [L]

it doesn't work. What am I doing wrong?

Answer 1

You have to take the value from the request line because Apache removes empty path segments. The initially requested URI path /http://foobar/ becomes /http:/foobar/. But the request line (THE_REQUEST) stays untouched:

RewriteCond %{THE_REQUEST} ^GET /(https?://[^s]+)
RewriteRule ^https?:/ index.php?url=%1 [L]