The ESP module can read a DHT11 or DHT22 temperature/Humidity sensor using a custom onewire protocol.
The DHT sensor needs to be connected to a configurable GPIO on the ESP module. In case you have a simple ESP-01 module, it's best to use the GPIO-2 pin.
Do not use GPIO015 as an input for the DHT11/22. During startup of the ESP8266, this pin must be Low for proper operation. It is better to avoid using GPIO00 as an input as well. This pin must be High at startup, unless program mode is required. The data pin of the DHT11/22 needs a pull-up resistor. A value of 4k7 - 10k proves to be sufficient.
Use the device tab on the ESP Easy webinterface and create a new task by editing one of the available tasks. Select "DHT Humidity Sensor" from the dropdown box.
Enter the IDX found in the Domoticz device page. Also select the GPIO pin that you have used to connect the DHT sensor. Finally you should select the type (DHT11 of DHT22). That should be all.
Syntax: DHTRead "type", "pin", "var"