rewrite rules for apache 2 to use with angular js

Question

Obviously, there are a lot of mod rewrite discussions and answers all across the web. However, I am having a hard time grasping them. So I thought I would ask here.

Answer 1

From my production server:

        ServerName XXX.com

        DocumentRoot /home/www/XXX.com/www

        # Local Tomcat server
        
          ProxyPass http://localhost:8080/api/
          ProxyPassReverse http://localhost:8080/api/
        

        RewriteEngine On

        # If an existing asset or directory or API is requested go to it as it is
        RewriteCond %{DOCUMENT_ROOT}%{REQUEST_URI} -f [OR]
        RewriteCond %{DOCUMENT_ROOT}%{REQUEST_URI} -d [OR]
        RewriteCond %{REQUEST_URI} /api
        RewriteRule ^ - [L]

        # If the requested resource doesn't exist (and is not API), use index.html
        RewriteRule ^ /index.html

        ErrorLog logs/XXX.com-error.log
        CustomLog logs/XXX.com-access.log common

Please note, that "!" before "/api" in the accepted answer is incorrect.