Linux Script - Send POST command from Raspberry Pi

I have a function on a residential solar inverter that needs be activated by a POST command. I use a Loxone home automation system to control many aspects of the solar inverter, however this particular function requires DIGEST authentication for sending the username/password and subsequent command. The home automation system is only capable of using BASIC authentication. I need to use an intermediary device that does have the capability to send a POST command with DIGEST authentication. I already have a Raspberry Pi with a custom firmware called 'Loxberry'. This is a minimalist version of Raspbian that has been developed by Loxone enthusiasts to 'fill the gaps' in the capabilities of the Loxone system. The end-state is to send a command from the home automation system to the Raspberry Pi that will activate the bash script. What I need is a bash script that will send the following command - http://<ip>/servicecgi-bin/suspend_battery_calibration/ PAYLOAD - {"suspension_time_seconds": 10800} <ip> is the address of the solar inverter in the home network. I know how to program the home automation system to activate bash scripts. I don't know anything about Linux, Python or how to write bash scripts. I have received some feedback in a forum for the Loxone enthusiasts. In this they say that the task should be a simple 'one-liner'. A call to 'stdout' and possibly adding a header may be required. Unfortunately they haven't provided the 'one-liner'!