Arduino and a Web Server
From your comment of Jul 1st, I understand that you can program your
server in PHP. Then, and to expand on my own comments, I am only
recommending that, whatever Web API you design, you keep it as simple as
possible. For example, for telling the Arduino whether it should keep
the shutter open or closed, you could write something like this in PHP:

header('Content-Type: text/plain');

if (user_wants_shutter_open())
    echo "open";
else
    echo "close";


In particular, it makes absolutely no sense to write a PHP program that
generates an HTML document. Consider that the Arduino is a very low
powered platform: there is no point in having it process more than a
handful of bytes when you only want to communicate a single bit of
information. And you should know that there is really nothing wrong with
using HTTP to transport plain text (but you should use the header
Content-Type: text/plain). If you want to send a more complex set of
data, you could use something like text/tab-separated-values, or maybe
even application/json.

Concerning web scrapping, it is a solution to a specific problem, the
problem being that the server returns the information in a format that
is not very well suited for machine consumption. You do not have this
problem. Obviously, you could create the problem by having your PHP
return an HTML document, and then you could apply the solution. My point
is that it is better to avoid creating the problem in the first place:
just return the information in a format that is as easy to parse as
possible.