To send an email directly from Golang you can use the package smtp which implements the Simple Mail Transfer
Protocol (SMTP) as defined in RFC 5321. You also need a mail server, for this tutorial will use the Gmail mail server.
Nginx is one of the most popular web servers in the world. It is also known to be more resource-friendly than Apache in most cases and can be used as a
web server or as a reverse proxy.
Firewalld is one of the Linux firewall management tool and it is available on the in the Ubuntu's default repositories, therefore it is available to
be installed from these repositories using the apt packaging system.
The switch statement is an easier way to have a sequence of if-else statements. In Golang you don't need to have break at the end of
each case, it breaks implicitly. Also the golang switch statement work on values of any type.
Golang programing language provides built-in suport for base64 decoding. The base64 functions are available into the
encoding/base64 package. It provides implementations for both Standard, with or without padding and Filename safe Base64 decoding variant.
