RESTful sensor failure behaviour

Configuration
1

Hi,

I have a RESTful sensor to read data from luno.com to get the latest Bitcoin value. The problem is, every now and then there’s a glitch and it fails to read the value. The default behavior is that it falls to 0 whereas I’d like to keep the previous value.

This is my sensor code:

  - platform: rest
    name: Luno Bitcoin in Rand
    resource: https://api.mybitx.com/api/1/ticker?pair=XBTZAR
    json_attributes:
      - last_trade 
      - timestamp
      - bid
      - ask
    value_template: '{{ value_json.last_trade }}' 
    unit_of_measurement: "ZAR"

Is there any way I can keep the value at the previous rather than fall to zero if it fails?

2

I’ve seen that behaviour and there is currently no caching functionality built in to the rest sensor. Sounds like a reasonable feature though. You probably want to display somewhere when the data was last fetched successfully, or maybe an icon that indicates that the data is not current anymore.

3

Is it possible to use another sensor (like a template) to read the restful data sensor, ignore the obviously wrong values and fall back to the previous value?

4

I just provided a solution to a similar problem in this post. Let me know if you’d like help converting it to your situation.