<VirtualHost *:80>
    ServerName example.com
    ServerAlias foo.example.com

    RewriteEngine On
    <Proxy *>
            Order Allow,Deny
            Allow from all
    </Proxy>
    <Location /api>
            ProxyPass http://example.com/api retry=0
            SetOutputFilter DEFLATE
    </Location>
</VirtualHost>

RewriteEngine On
<Proxy *>
        Order Allow,Deny
        Allow from all
</Proxy>
<Location /api>
        ProxyPass http://example.com/ retry=0
        SetOutputFilter DEFLATE
</Location>