Have you ever tried to deploy your React App to a subdirectory like

http://my-website.com/my-new-app/

or even a local file path like

file:///android_asset/my-embedded-app/

and were stuck with a blank screen?

I was just recently.

The reason for this can easily be found by inspecting the web-page. You will see error messages like a needed resource *.chunk.1234.js could not be loaded.

Reason: wrong include path.

By default, the react-app will be build in a way that resources are linked absolute, beginning with a forward-slash /. So if you try to deploy your app to something like http://my-website.com/my-new-app/ it will not work because your app will request assets from http://my-website.com/ instead of your my-new-app sub-directory.

The Fix

React-side

Go to your package.json and add the following line:

"homepage": "."

What it does? During the build it handles all paths as if they were related to your current directory. So as soon as you load your index.html, all static files are linked relatively to your index.html.

Unfortunately, if you have a funky custom routing system, this approach could not work for you. If you use react-router, it could be mandatory to set a basepath that matches your desired sub-directory depending on the router implementation you might use.

Web-Server

Keep in mind that you also have to configure your web-server correctly:

// nginx

server {
    server_name my-website.com;
    ...
    
    location ~ /my-new-app {
        root ...;
        try_files $uri /my-new-app/index.html;
    }
}

References