SHELL() Function Asterisk 13 – Can Only Accept One Paramter In String?

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Asterisk Users 4 Comments

Hi all

This is a followup on my post “Asterisk 13 – system() dialplan app cannot call bash scripts” from yesterday

I’ve given up trying to use system() to call BASH scripts with parameters from Asterisk 13. Turned out under Asterisk 13.22.0 System() DOES work, but only if you do NOT attempt to pass any parameters to the called script.

This works, and reliably calls the script:

same=>n,System(/bin/bash /usr/src/bash/setData.sh)

However, the moment you do this:

same=>n,System(/bin/bash /usr/src/bash/setData.sh ${CHANNEL(accountcode)})

you get

WARNING[30982][C-00000238] app_system.c: Unable to execute ‘/usr/src/bash/setData.sh’

I therefore tried to use SHELL() to do what I was trying to do with SYSTEM().

This also does not work, as SHELL() apparently can only ever parse ONE asterisk parameter in the string sent to it. All the rest are sent as blank.

If I do this:

same=>n,Set(nothing=${SHELL(/usr/src/verdi/bash/verdiLogIncomingCall.sh NA 201807270838t49hgzs SIP/centra-out-00006d9a IN SIP/3027-00006db1 SIP/3027-00006db1 ApiLogIncomingCall.java 1)})

The script sees, on dialplan execution:

[root@acasterisk bash]# cat passed_param.txt http://127.0.0.1/api/logIncomingCall?account_reference=NA&call_reference=201807270838t49hgzs&originating_channel_id=SIP/centra-out-00006d9a&direction=IN&requested_endpoint=SIP/3027-00006db1&caller_id=SIP/3027-00006db1&sourced_from=ApiLogIncomingCall.java&successfully_sent_to_server=1
[root@acasterisk bash]#

E. g. all params present – because no variable references need to be parsed.

If I use this:

[macro-verdianswer]
exten=>s,1,NoOp(Entering Verdi answer macro – picked up by ${CHANNEL})
same=>n,NoOp(Source Channel: ${sourceChannel})
same=>n,NoOp(Answering Channel: ${CHANNEL})
same=>n,NoOp(Lodging CDR accountcode: ${curIncAccCode} as an incoming call from ${numbersource} with VerDi and answered by ${CHANNEL}…)
same=>n,Set(CHANNEL(accountcode)=${curIncAccCode})
same=>n,Set(nothing=${SHELL(/usr/src/verdi/bash/verdiLogIncomingCall.sh NA ${curIncAccCode} ${sourceChannel} IN ${CHANNEL} ${numbersource} ApiLogIncomingCall.java 1)})
same=>n,MacroExit()

giving this on exection:

— SIP/3002-000070c2 answered SIP/centra-out-000070bf
— Executing [s@macro-verdianswer:1] NoOp(“SIP/3002-000070c2”, “Entering Verdi answer macro – picked up by SIP/3002-000070c2”) in new stack
— Executing [s@macro-verdianswer:2] NoOp(“SIP/3002-000070c2”, “Source Channel: SIP/centra-out-000070bf”) in new stack
— Executing [s@macro-verdianswer:3] NoOp(“SIP/3002-000070c2”, “Answering Channel: SIP/3002-000070c2”) in new stack
— Executing [s@macro-verdianswer:4] NoOp(“SIP/3002-000070c2”, “Lodging CDR accountcode: 2018072709061hrriyu
— as an incoming call from 27182941000 with VerDi and answered by SIP/3002-000070c2…”) in new stack
— Executing [s@macro-verdianswer:7] Set(“SIP/3002-000070c2”, “nothing=Incoming call NOT stored. Contact software support.
— “) in new stack

e. g. my variables ARE populated, and if I NoOp them, they have values.

In this situation, the script called via SHELL() sees:

[root@acasterisk bash]# cat passed_param.txt http://127.0.0.1/api/logIncomingCall?account_reference=NA&call_reference=2018072709061hrriyu&originating_channel_id=&direction=&requested_endpoint=&caller_id=&sourced_from=&successfully_sent_to_server=

E. g. SHELL() apparently only ever parses the FIRST Asterisk variable passed into it as a string, and never parses subsequent variable references.

Can anybody confirm or suggest a solution?

I desperately need to be able to execute external BASH scripts and pass multiple parameters to them, somehow. Nothing that worked in 1.8 for this works in 13…

Thanks!

Stefan

—

4 thoughts on - SHELL() Function Asterisk 13 – Can Only Accept One Paramter In String?

  • Le 27/07/2018 à 09:36, Stefan Viljoen a écrit :

    […]

    *CLI> core show version Asterisk 13.22.0 built by root @ pabx on a x86_64 running Linux on
    2018-07-14 13:36:49 UTC

    This works for us

    same = n,system(/bin/echo “To: ${CALLED_CHANNEL} From: ${ORI_CALL}” |
    /usr/bin/mail -s “TOOTAiAudio – Congestion Gateway ${CONGESTION_GW}
    used” ${AUDIO_ADMIN})

    —
    Daniel

    —

  • Hi Stefan,

    You might use AGI instead of SHELL, it’s better because you can interact with the call via AGI and you don’t have a risk of remote execution you might have if you add arguments that come from outside, for example via a SIP header.

    Regards.

  • With thanks to Ludovic Gasc

    —

    Turns out there is nothing wrong with the SYSTEM() or SHELL() dialplan functions in Asterisk 13.22.0.

    After several hours of painstaking debugging, the problem turned out to be a linefeed (\n character, 0x0a hex) in the first parameter passed from Asterisk to the bash script in the call to the SYSTEM() or SHELL() applications.

    Ludovic’s suggestion to try AGI revealed the issue – it has nothing to do with AGI or SYSTEM() but rather my data for one parameter passed through system containing a linefeed (\n)….

    E. g. I was calling this:

    same=>n,System(/usr/src/verdi/bash/verdiLogIncomingCall.sh NA ${curIncAccCode} ${sourceChannel} IN ${CHANNEL} ${numbersource} ApiLogIncomingCall.java 1)

    but

    ${curIncAccCode}

    appeared to contain a UUID I generate in a JAVA application.

    In fact it contained

    uuidtexthere\n

    instead of just

    uuidtexthere

    E. g. it had an appended \n (hex 0a) linefeed character appended.

    My script that generated this UUID looked like this:

    —
    #!/bin/bash function jsonval {
    temp=`echo $jsonResult | sed ‘s/\\\\\//\//g’ | sed ‘s/[{}]//g’ | awk -v k=”text” ‘{n=split($0,a,”,”); for (i=1; i<=n; i++) print a[i]}' | sed 's/\"\:\"/\|/g' | sed 's/[\,]/ /g' | sed 's/\"//g'` echo ${temp##*|} } baseUrl=http://127.0.0.1/api/getVerdiUUID jsonResult=$(curl --connect-timeout 16 --max-time 32 -s -X GET $baseUrl) uuid=`jsonval` echo $uuid --- So all that I actually needed to fix was to change echo $uuid to echo -n $uuid and all my problems were solved, SYSTEM() started working perfectly everywhere in the dialplan as the script wasn't emitting a trailing \n anymore. So the germane difference between Asterisk 1.8 and Asterisk 13 / 12 / 11 / 10 in this case was that SYSTEM() and SHELL() in the later versions are sensitive to \n being passed in inside any of the Asterisk variables passed into those applications' parameter string. Maybe this helps somebody else. Regards Stefan --

  • ——=_NextPart_001_0095_01D425B1.C0EEC6A0
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    Hi Ludovic

    Thank you very much for replying!

    Ok, I’ll give up on the dialplan apps then in total and try out AGI.

    Thanks again,

    From: Ludovic Gasc
    Sent: Friday, 27 July 2018 13:37
    To: viljoens@verishare.co.za; Asterisk Users Mailing List – Non-Commercial Discussion
    Subject: Re: [asterisk-users] SHELL() function Asterisk 13 – can only accept one paramter in string?

    Hi Stefan,

    You might use AGI instead of SHELL, it’s better because you can interact with the call via AGI and you don’t have a risk of remote execution you might have if you add arguments that come from outside, for example via a SIP header.

    Regards.