Hello, I’m looking to send data from my openhab controller to a server I’ve rented. Is there already an addon which can achieve this, either via TCP or HTTP?
Several options:
MQTT: Send messages to a topic at your server
Database connection like MySQL: make direct connection to a database at your server
etc…
Depends on what you would like to do so a bit more background will give you a better answer 
One option is to use the Exec persistence service. (The doc site currently mislabels it a 2.x, auto-installable service, but this bug I introduced should be fixed soon.) You would drop the .jar file in your addons directory.
Every time openHAB wants to persist a state, it will run a command you specify, passing the current time and the state as a string. You can call cURL, your own script, or anything command that can be run by the user under which the openHAB server is running.
If you do this and it works, please report back, so we can make it directly installable from Paper UI or addons.cfg. Thanks!
This is what I was planning on doing if there was no addon for this. I will report back if it works