Command line command is not executed

Setup, Configuration and Use Scripts & Rules
1

I want to add a record to a csv file each time when my item is updated.
I have a rule with action:

...
then
	val String ms_val = String_MS_raw.state.toString

	executeCommandLine(String::format("echo \"%2$s;%1$s\" >> /media/data/big_storage/Temp/meteostation.csv", ms_val, now))

In log it says

17:47:26.759 [DEBUG] [AbstractDatagramChannelBinding:1389 ] - Received meteostation;1116;273;23;36 on the listener port from /0.0.0.0:4321
17:47:26.759 [DEBUG] [i.s.RegExTransformationService:42 ] - about to transform ā€˜meteostation;1116;273;23;36ā€™ by the function ā€˜meteostation;(.*)ā€™
17:47:26.760 [DEBUG] [t.protocol.internal.UDPBinding:276 ] - transformed response is ā€˜1116;273;23;36ā€™
17:47:26.760 [DEBUG] [m.r.internal.engine.RuleEngine:305 ] - Executing rule ā€˜Parse raw meteostationā€™
17:47:26.760 [INFO ] [runtime.busevents :26 ] - String_MS_raw state updated to 1116;273;23;36
> 17:47:26.762 [INFO ] [g.openhab.io.net.exec.ExecUtil:64 ] - executed commandLine ā€˜echo ā€œ2016-02-29T17:47:26.761+02:00;1116;273;23;36ā€ >> /media/data/big_storage/Temp/meteostation.csvā€™
17:47:26.764 [INFO ] [runtime.busevents :26 ] - MS_Temperature state updated to 23
17:47:26.765 [INFO ] [runtime.busevents :26 ] - MS_Humidity state updated to 36
17:47:26.766 [INFO ] [runtime.busevents :26 ] - MS_CO2_Raw state updated to 273

However actually the line is not added to file as expected. If I run the command separatelly in command line - line is adding.
My system is ubuntu 14.04

2

Two possibilities I can think of:

  1. The user under which the openHAB server is running does not have permission to write to the file /media/data/big_storage/Temp/meteostation.csv, whereas the user under which you are logged in at a command prompt does have permission.
  2. You donā€™t have access to shell syntax like >>, in which case you could write and invoke a two-line Bash script instead:
#!/bin/bash
echo "$2;$1" >> /media/data/big_storage/Temp/meteostation.csv

so your rule would change to something like

executeCommandLine("/home/openhab/bin/append.sh" + ms_val + " " + now.toString)

remember to set the executable bit and ownership such that the user under which the openHAB server is running can run the script, for example:

sudo chown openhab:openhab /home/openhab/bin/append.sh
sudo chmod +x /home/openhab/bin/append.sh
1 Like
3

Thanks
This works fine for me. Just checked. Slightly modified solution

Bash script

#!/bin/bash
echo $1 >> $2

rule code

val String ms_val = String_MS_raw.state.toString
executeCommandLine(String::format("/media/data/big_storage/Projects/electronics/co2/append.sh %2$s;%1$s /media/data/big_storage/Temp/meteostation.csv", ms_val, now))
1 Like
4

May I ask why do you not use the logging action or the logging persistence?

5

Does it allow to store files in csv format?
If not I think it would be nice to have additionally textual persistence (which would allow to save csv as well)

6

CSV is a separated formatted text. So only the suffix is another one.
I think if you define your csv file in the logback.xml and use the logging-action (logInfo, ā€¦) within your rule, you should be fine!

7

Yes, the logging persistence can be configured to save your items as CSV. See the Logging Persistence wiki page for details.

I highly recommend using the version of executeCommandLine that returns the results and logging those results. I find the Exec binding and executeCommandLine to be pretty brittle and it saves tons of time to actually have the results from executing a command already in your logs.

val results = executeCommandLine("/home/openhab/bin/append.sh" + ms_val + " " + now.toString, 5000)
logInfo("Results", results)

This doesnā€™t help now that you have it working but will help you when it suddenly stops someday.