Extract line from log to trigger an automation

Configuration
1

Hi everyone,

I’m trying to trigger an automation based on an error string in the log.
I created a .sh file with this command inside:

if grep -i "Switchbot communication failed" /config/home-assistant.log >/dev/null; then echo "ON"; else echo "OFF"; fi

Then on my configuration.yaml I’m using a binary sensor:

binary_sensor:
  - platform: command_line
    command: "/config/switchbot_error.sh"
    name: "Switchbot Error"

I need help to understand why it’s not working. Thanks

2

Define “not working”, maybe?

What is the state of the binary sensor?
Something in the logs?

3

The state is always off but when I run the command from Terminal, the binary sensor state is set accordingly.

On the log I got just

2021-05-16 11:09:31 ERROR (SyncWorker_2) [homeassistant.components.command_line] Command failed: /config/switchbot_error.sh
4

That’s a big hint, isn’t it :wink:

Maybe try

command: "sh /config/switchbot_error.sh"
5

I don’t get the error anymore but it’s still not changing the binary sensor state

6

Be careful that command_line sensors only update once per minute, by default.
Also, I assume you took care of potential permissions issues?

7

Thanks for your help, I didn’t know the command_line updates once per minute. It seems to be working now

8

The polling frequency is governed by the scan_interval option and the default is 60 seconds.

scan_interval integer (optional, default: 60)
Defines number of seconds for polling interval