Some time ago I tried to use Node-RED but it did not work for me. Lack of reading docs I’d guess now. When I tried it again some days ago, it worked just fine and created quickly nice temperature diagrams with my nodeMCU and a 1-wire DS18B20 temperature probe.
Here you can see the temperature over the last 4 days. The shark peak is me holding the temperature sensor. Fast temperature drops are caused by the air conditioning.
This is all with a relative accuracy of 0.0625°C. Absolute accuracy is much less. See the data sheet of the DS18B20. Or read this for fun and education about absolute calibration.
BTW, my Node-RED runs on my Banana Pi BPI-M1 (via Ethernet cable as WiFi caused instable network connections as well as full blown random crashed). MQTT server is on the cloud in a Docker container on my Linode VM.