How to redirect subdomain to another rails project

The easiest way to serve two separate Rails apps from the same Droplet is to use an Nginx reverse proxy. If you’re not already doing so, take a look at this tutorial:

• How To Deploy a Rails App with Unicorn and Nginx on Ubuntu 14.04

Bellow is a sample Nginx configuration based on the one used by the DigitalOcean Rails One-Click app. You’ll see a few key things. First, it is important to set the server_name directives so that Nginx can correctly route requests to the apps based on their domain names.

Next you’ll see that we created a new upstream server. The Unix socket file that it points to is defined in listen directive in the Unicorn configuration for your project.

upstream app_server {
    server unix:/var/run/unicorn.sock fail_timeout=0;
}

upstream project2_server {
    server unix:/var/run/project2.sock fail_timeout=0;
}

server {
    listen   80;
    root /home/rails/rails_project/public;
    server_name myapp.com;
    index index.htm index.html;

    location / {
            try_files $uri/index.html $uri.html $uri @app;
    }

    location ~* ^.+\.(jpg|jpeg|gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|pdf|ppt|txt|tar|mid|midi|wav|bmp|rtf|mp3|flv|mpeg|avi)$ {
                    try_files $uri @app;
            }

     location @app {
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header Host $http_host;
            proxy_redirect off;
            proxy_pass http://app_server;
    }
}

server {
    listen   80;
    root /home/rails/project2/public;
    server_name test.myapp.com ;
    index index.htm index.html;

    location / {
            try_files $uri/index.html $uri.html $uri @app;
    }

    location ~* ^.+\.(jpg|jpeg|gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|pdf|ppt|txt|tar|mid|midi|wav|bmp|rtf|mp3|flv|mpeg|avi)$ {
                    try_files $uri @app;
            }

     location @app {
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header Host $http_host;
            proxy_redirect off;
            proxy_pass http://project2_server;
    }
}