how do you parse whether "relay_state" is ON or OFF?

[Piotr-23]

I have a bash script that should run your script (thanks for it, BTW! :) and return whether the "relay_state" is ON or OFF

#!/bin/bash

STATUS_103=$(source "/home/piotr/_kasa_hs100/hs100-nealefelaen.py 192.168.0.103 9999 status")
echo "STATUS OF 103: ..." $STATUS_103
printf "\n"

but this gives me just

./mainscript.sh: line 36: {"system":{"get_sysinfo":{"sw_ver":"1.1.5 Build 200828 Rel.081157","hw_ver":"4.0","model":"HS100(EU)","","oemId":"","hwId":"","rssi":-54,"longitude_i":,"latitude_i":_,"alias":"Extra","status":"new","mic_type":"IOT.SMARTPLUGSWITCH","feature":"TIM","mac":"1C:3B:F3:DE:7D:AF","updating":0,"led_off":0,"relay_state":0,"on_time":0,"active_mode":"schedule","icon_hash":"","dev_name":"Smart Wi-Fi Plug","next_action":{"type":-1},"err_code":0}}}: File name too long
STATUS OF 103: ...

File name to long?
How to extract 0
? Thanks and best | P

[Nealefelaen]

If I'm parsing what is happening correctly then "File name too long" is bash telling you it's trying to source the response of the command as a file name (which is way too many characters).
You want to use simply:
STATUS_103=$(/home/piotr/_kasa_hs100/hs100-nealefelaen.py 192.168.0.103 9999 status)

And if you want to be really fancy (and have jq installed - jq parses JSON data nicely) you could do:
STATUS_103=$(/home/piotr/_kasa_hs100/hs100-nealefelaen.py 192.168.0.103 9999 status | jq '.system.get_sysinfo.relay_state');
Which will put '1' in STATUS_103 if the relay_state is on and '0' if it's off :)

Oh, and I should mention that the usage/watt-hours commands aren't especially useful (I was just grabbing the encoded command string that I was getting from Kasa querying the device; turns out it asks for the watt-hours for a certain date range. I wandered off to other projects before writing a proper implementation.)

[Piotr-23]

Thank you! It works perfectly!
But how to call the hs100.py script from a bash script to turn device ON, without displaying json message?

I do
( exec /usr/bin/python3 /home/piotr/_kasa_hs100/hs100-nealefelaen.py 192.168.0.103 9999 on )
and I get
{"system":{"set_relay_state":{"err_code":0}}}

Thanks | P

[Nealefelaen]

:D That's a Linux question too - you can redirect the output of a command to /dev/null (which just throws it away):
exec /usr/bin/python3 /home/piotr/_kasa_hs100/hs100-nealefelaen.py 192.168.0.103 9999 on > /dev/null
> /dev/null is just saying "Take everything that is put on stdout (standard out) and put it in /dev/null (which just discards it)".

Not relevant for this script/program (it outputs everything to stdout) but you can also tell everything that is put on stderr (standard error) to go to stdout which you can then throw away:
... 2>&1 > /dev/null
Which in English is saying "Take everything from output stream 2 (stderr) and put it on output stream 1 (stdout), then put everything from stdout into /dev/null (which throws it away)".

[Piotr-23]

Thanks Nealefelaen - it works perfectly now. Best | P