Changing Root Path in Nginx based on Cookie

If you want to change the root path of a domain in the Nginx web server based on a cookie then you can put the following lines of code in the sites conf file, ie the file within sites-available folder in /etc/nginx/ directory.

 map $http_cookie $rootpath {
	"~*revert_in"  "/var/www/path to/htdocs";
	default                 "/var/www/original/htdocs";
  }
server {
    server_name test1.loantap.in   www.test1.loantap.in;
    ...
    ...
    ...
    root $rootpath;
    ...
    ...
    ...
}

map $http_cookie $rootpath {

"~*revert_in" "/var/www/path to/htdocs";

default "/var/www/original/htdocs";

}

server {

server_name test1.loantap.in www.test1.loantap.in;

...

root $rootpath;

...

}

The MAP directives allow us to set the $rootpath variable based on conditions specified below. This $rootpath is then used to set the path in server directive.
This technique allows us to test files level changes on a production website with an existing database.

Updated on Dec 14, 2017