getting the group name to the according pri port in asterisk

Question

I am using sagoma 8 port card My chan_dahdi.conf to configure the ports are

;autogenerated by /usr/sbin/wancfg_dahdi do not hand edit
;autogenrated on 2015-06-12
;Dahdi Channels Configurations 
;For detailed Dahdi options, view /etc/asterisk/chan_dahdi.conf.bak

[trunkgroups]

[channels]
context=default
usecallerid=yes
hidecallerid=no
callwaiting=yes
usecallingpres=yes
callwaitingcallerid=yes
threewaycalling=yes
transfer=yes
canpark=yes
cancallforward=yes
callreturn=yes
echocancel=yes
echocancelwhenbridged=yes
relaxdtmf=yes
rxgain=0.0
txgain=0.0
group=1
callgroup=1
pickupgroup=1
immediate=no

;Sangoma A108 port 1 [slot:4 bus:2 span:1] <wanpipe1>
switchtype=euroisdn
context=from-pstn
group=1
echocancel=yes
signalling=pri_cpe
channel =>1-15,17-31

;Sangoma A108 port 2 [slot:4 bus:2 span:2] <wanpipe2>
switchtype=euroisdn
context=from-pstn
group=2
echocancel=yes
signalling=pri_cpe
channel =>32-46,48-62

;Sangoma A108 port 3 [slot:4 bus:2 span:3] <wanpipe3>
switchtype=euroisdn
context=from-pstn
group=3
echocancel=yes
signalling=pri_cpe
channel =>63-77,79-93

;Sangoma A108 port 4 [slot:4 bus:2 span:4] <wanpipe4>
switchtype=euroisdn
context=from-pstn
group=4
echocancel=yes
signalling=pri_cpe
channel =>94-108,110-124

;Sangoma A108 port 5 [slot:4 bus:2 span:5] <wanpipe5>
switchtype=euroisdn
context=from-pstn
group=5
echocancel=yes
signalling=pri_cpe
channel =>125-139,141-155

;Sangoma A108 port 6 [slot:4 bus:2 span:6] <wanpipe6>
switchtype=euroisdn
context=from-pstn
group=6
echocancel=yes
signalling=pri_cpe
channel =>156-170,172-186

;Sangoma A108 port 7 [slot:4 bus:2 span:7] <wanpipe7>
switchtype=euroisdn
context=from-pstn
group=7
echocancel=yes
signalling=pri_cpe
channel =>187-201,203-217

;Sangoma A108 port 8 [slot:4 bus:2 span:8] <wanpipe8>
switchtype=euroisdn
context=from-pstn
group=8
echocancel=yes
signalling=pri_cpe
channel =>218-232,234-248

My problem is how can I get the group number of current calling port dynamically in my dialplan.

For example if user call to the pri which is in port 1 then my dial statement is

exten => _X.,n,dial(DAHDI/g1/${NUMBER})

And for the call on second pri port 2

 exten => _X.,n,dial(DAHDI/g2/${NUMBER})

g3,g4,g5 etc for other ports in order to set that particular DID

Currenty what I am doing when call comes I create a GROUP variable which stores the group by checking DID range

same => n,Set(__GROUP=${IF($[ ${EXTEN} >= ${DIDMINPORT1}]? ${IF($[ ${EXTEN} <=  ${DIDMAXPORT1}]?g1:g1)} :g1)})
same => n,Set(__GROUP=${IF($[ ${EXTEN} >= ${DIDMINPORT2}]? ${IF($[ ${EXTEN} <= ${DIDMINPORT2}]?g2: ${GROUP} )} : ${GROUP} )})

and etc for other groups ,for dialling I do

   exten => _X.,n,dial(DAHDI/${GROUP}/${NUMBER})

But I dont think its a good idea because I have 8 port so I have to write 8 lines to determine the group and dial by matching the DID.So is there any way to get group dynamically in my dialplan means if there any channel variable from which I can get the group of current incoming port call?

Answer 1

As I know there are no such variables for that DAHDI groups.

In your chan_dahdi.conf you use same option "context=from-pstn", so you may easily set "context=pri-g1" for group 1 ("context=pri-g2" for group 2 and etc.) and then define in dialplan something like that:

[pri-main]
exten => s,1,NoOp(Main routine)

[pri-g1]
exten => s,1,Set(PRI_GROUP=1)
exten => s,n,GoTo(pri-main,s,1)

[pri-g2]
exten => s,1,Set(PRI_GROUP=2)
exten => s,n,GoTo(pri-main,s,1)

...

[pri-g8]
exten => s,1,Set(PRI_GROUP=8)
exten => s,n,GoTo(pri-main,s,1)

It is not as convenient for setting up as if there were channel variables, but fast for asterisk.

Just notice that in [pri-g#] exten may be not "s", but DID number or smth else - but you will see it in CLI errors very soon.

Answer 2

By occasion found just what you want - you can set variables in chan_dahdi.conf like that:

[channels]
...
group=1
setvar=__GROUP=1
...

group=2
setvar=__GROUP=2
...

(and so on)

After this you can use your dialplan from question.