Based on https://www.adafruit.com/product/2935 and a Raspberry Pi Zero.
https://youtu.be/tN2z2cZIZbc?t=1365
You must configure the Raspberry Pi on your network for the first use. Connect a monitor/keyboard/mouse to find your DHCP address or to configure your wireless connection. You might want to change the default login credentials from "pi/raspberry".
To control the power, point your web-browser to the IP address. The landing page shows you the status of the relay. You have buttons to turn the power on and off.
You can also use curl
to script power control with GET operations on the following URLs:
/relay
Check the status of the relay ("True" or "False")/relay/on
Turn the relay on/relay/off
Turn the relay off