if Nginx does not find a http_cookie then try serving a static file, otherwise fallback to php

Question

I'm relatively new to nginx and am struggling to understand some of it's concepts.

I have a php application, I also have static html files which I wish to serve to uses who are not logged in. I can determine this by the presence of an http cooke ( which 'loggedin' will be set to 1 if logged in or it will not to present or set to 0 if the user is not).

The static file may or may not be available to the logged out user, if not then I want php to handle the request

My best attempt at solving this is like this

location / {
    if ($http_cookie ~* "loggedin" ) {
        set $cachepath '/cache$request_uri.html';

    }
    try_files $cachepath $uri /index.php?$query_string;

}

But that does not work. Also worth noting is my php application serves urls like so www.website.com/about-us/ (with a trailing slash on the end) . So looking for the cache file like above, will look like this cache/about-us/.html when it should be this cache/about-us.html. Also I have a static home page called index.html, and i'm not sure how to serve that either.

Thanks to anyone who can help me.

Answer 1

You need to extract the basename from the URI with the trailing / and then test if the file exists. One approach is to use a regular expression location with a named capture. See this document for more.

For example:

location ~ ^/(?<name>[^/]+)/ {
    if ($http_cookie ~* "loggedin") {
        rewrite ^ /index.php last;
    }
    if (-f $document_root/cache/$name.html) { 
        rewrite ^ /cache/$name.html last;
    }
    rewrite ^ /index.php last;
}
location / { ... }
location ~ \.php$ { ... }

The first location block only handles URIs consisting of a name and a trailing / . The first if block redirects to PHP if the cookie exists (I think the logic in your question was inverted). The second if block tests for the presence of a matching cache file.

See this caution on the use of if .