nginx alias

A path to the file is constructed by merely adding a URI to the value of the root directive. If a URI has to be modified, the alias directive should be used

Syntax:	alias path;
Default:	—
Context:	location

Defines a replacement for the specified location. For example, with the following configuration

location /i/ {
    alias /data/w3/images/;
}

on request of “/i/top.gif”, the file /data/w3/images/top.gif will be sent.

The path value can contain variables, except $document_root and $realpath_root.

If alias is used inside a location defined with a regular expression then such regular expression should contain captures and alias should refer to these captures (0.7.40), for example:

location ~ ^/users/(.+.(?:gif|jpe?g|png))$ {
    alias /data/w3/images/$1;
}

When location matches the last part of the directive’s value:

location /images/ {
    alias /data/w3/images/;
}

it is better to use the root directive instead:

location /images/ {
    root /data/w3;
}