HTTP to HTTPS redirect for WordPress on Azure Web App on Linux

If you host WordPress site on Azure Web App on Linux running Apache, here are the steps to implement HTTP to HTTPS redirect:

1. Add RewriteRule in .htaccess in WordPress application root

 RewriteCond %{HTTP:X-ARR-SSL} ^$
 RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

2. Once this RewriteRule is added, you may see wp-admin page lost style like this, this is caused by loading mixed content from http and https,

Image may be NSFW.
Clik here to view.

Here is a way to fix this, add following code in wp-config.php,

define('FORCE_SSL_ADMIN', true);
if ( isset($_SERVER['HTTP_X_ARR_SSL']) )
        $_SERVER['HTTPS']='on';