How to send HTTP Commands through Port 80 - sockets

Question

Breif Description of what I am trying to accomplish. So I am working with Crestrons Simpl+ software. My job is to create a module for a sound masking system called QT Pro. Now, QT Pro has an API where you can control it via HTTP. I need a way to establish a connection with the QT Pro via HTTP( I have everything I need, IP, Username, Password).
Whats the problem? I have just started working with this language. Unfortunately there isn't as much documentation as I would like, otherwise I wouldn't be here. I know I need to create a socket connection via TCP on port 80. I just don't know what I'm supposed to send through it.
Here is an example:
http://username:password#address/cmd.htm?cmd=setOneZoneData&ZN=Value&mD=Value
&mN=Value&auxA=Value&auxB=Value&autoR=Value
If I were to put this into the URL box, and fill it in correctly. then it would change the values that I specify. Am I supposed to send the entire thing? Or just after cmd.htm? Or is there some other way I'm supposed to send data? I'd like to stay away from the TCP/IP Module so I can keep this all within the same module.
Thanks.

Answer 1

You send
GET /cmd.htm?cmd=setOneZoneData&ZN=Value&mD=Value&mN=Value&auxA=Value&auxB=Value&autoR=Value HTTP/1.1
Host: address
Connection: close
(End with a couple of newlines.)
If you need to use HTTP basic authentication, then also include a header like
Authorization: Basic dXNlcm5hbWU6cGFzc3dvcmQ=
where the gibberish is the base64-encoded version of username:password.
But surely there is some mechanism for opening HTTP connections already there for you? Just blindly throwing out headers like this and hoping the response is what you expect is not robust, to say the least.
To see what is going on with your requests and responses, a great tool is netcat (or telnet, for that matter.)
Do nc address 80 to connect to server address on port 80, then paste your HTTP request:
GET /cmd.htm HTTP/1.1
Host: address
Authorization: Basic dXNlcm5hbWU6cGFzc3dvcmQ=
Connection: close
and see what comes back. SOMETHING should come back. (Remember to terminate with two newlines.)
To see what requests your browser is sending when you do something that works, you can listen like this: nc -l -p 8080.
Then direct your browser to localhost:8080 with the rest of the URL as before, and you'll see the request that was sent. (Then you can type back to see how the browser handles the response.)