Secure httpPostJson? Encryption?

I have an app that transmits event data to my personal server.
The main function is httpPostJson(…).
Data is sent in the body of the POST as plain text, right?
Is there a way to encrypt the data with any of the standard encryption algorithms?

What URI are you using? My understanding (and I could be wrong!) is that as long as your URI is “https://…” the data will all be encrypted.