This project is for the solar-powered Wemos D1 mini with a DS18B20 temperature sensor and a Capacitive Moisture sensor.
Here is a project by Nick Gammon that uses a supercap instead of a battery. https://www.gammon.com.au/forum/?id=12821
The publish functions expect char[] types to be passed in rather than Strings. You need to use the String.toCharArray() function to convert your strings to the necessary type.
char charBuf[50]; stringOne.toCharArray(charBuf, 50) myString.toCharArray(buf, len)
For future reference: #include <IPAddress.h> IPAddress ipAddress(192, 168, 0, 1);