Call-Back Service for IP-Telephony users Part-II

Continuing with the Auto-Call-Back service. In the previous part of this post we collected Callers numbers in a Call Back Queue for each IP-PBX user. Once we've List saved for each user, next thing would be to enable the service users to call to the service listen to their Callers Numbers and if Service user wants to call-back then dial it else move onto next caller in the list.

See the Flow-diagram on right for the above.

What we'll learn:

1- Dial-plan function DB_EXIST
2- Dial-plan Application SayDigits, and Read.
3- Misc: See some more scenarios of using previously used functions and applications.

Call-Back Service Dial-Plan code:


exten => 747,1,NOOP(PBX User ${CALLERID(num)} Reading Call-Back Data)
same => n,Answer()
same => n,GOTOIF(${DB_EXISTS(call-back/${CALLERID(num)})}?:hangup)
same => n,SET(CBQ=${DB(call-back/${CALLERID(num)})})
same => n,Playback(vm-youhave)
same => n,SayDigits(${FIELDQTY(CBQ,-)})
same => n,Playback(vm-messages)
same => n,SET(i=${FIELDQTY(CBQ,-)})
same => n,WHILE($["${i}" >= "1"])
same => n,Playback(vm-from-phonenumber)
same => n,SayDigits(${CUT(CBQ,,${i})})
same => n,Read(INPUT,vm-dialout,1)
same => n,SET(DIALME=${CUT(CBQ,,${i})})
same => n,GOTOIF($["${INPUT}" == "1"]?yes)
same => n,EXECIF($["${SaveCBQ}" == ""]?SET(SaveCBQ=${CUT(CBQ,,${i})}):SET(SaveCBQ=${CUT(CBQ,,${i})}-${SaveCBQ}))
same => n,SET(i=$[${i} - 1])
same => n,EndWhile()
same => n,hangup()
same => n(yes),SET(ARRAY(CBQ,j)=${CUT(CBQ,,1-$[${i} - 1])}-${SaveCBQ},${i})
same => n,NOOP([CBQ:1]= ${CBQ:1} :: [CBQ:0:-1]=${CBQ:0:-1} :: [CBQ:-1]=${CBQ:-1})
same => n,EXECIF($["${CBQ:-1}" == "-"]?SET(CBQ=${CBQ:0:-1}))
same => n,EXECIF($["${CBQ:0:1}" == "-"]?SET(CBQ=${CBQ:1}))
same => n,SET(DB(call-back/${CALLERID(num)})=${CBQ})
same => n,Dial(SIP/${DIALME})
same => n(hangup),Hangup()

So, once UserK calls into CBS number 747, we'll follow the flow-chart and try establish call between the userK and the callers.

All Dial-Plan Code:

[default]

exten => _X.,1,NOOP(Incoming Call from ${CALLERID(num)} to ${EXTEN})

same => n,Answer()

same => n,SET(DEST=${EXTEN})

same => n,Dial(SIP/${EXTEN},10)

same => n,Voicemail(${EXTEN}@default,d(register-callback))

same => n,Hangup()

exten => 747,1,NOOP(PBX User ${CALLERID(num)} Reading Call-Back Data)

same => n,Answer()

same => n,GOTOIF(${DB_EXISTS(call-back/${CALLERID(num)})}?:hangup)

same => n,SET(CBQ=${DB(call-back/${CALLERID(num)})})

same => n,Playback(vm-youhave)

same => n,SayDigits(${FIELDQTY(CBQ,-)})

same => n,Playback(vm-messages)

same => n,SET(i=${FIELDQTY(CBQ,-)})

same => n,WHILE($["${i}" >= "1"])

same => n,Playback(vm-from-phonenumber)

same => n,SayDigits(${CUT(CBQ,,${i})})

same => n,Read(INPUT,vm-dialout,1)

same => n,SET(DIALME=${CUT(CBQ,,${i})})

same => n,GOTOIF($["${INPUT}" == "1"]?yes)

same => n,EXECIF($["${SaveCBQ}" == ""]?SET(SaveCBQ=${CUT(CBQ,,${i})}):SET(SaveCBQ=${CUT(CBQ,,${i})}-${SaveCBQ}))

same => n,SET(i=$[${i} - 1])

same => n,EndWhile()

same => n,hangup()

same => n(yes),SET(ARRAY(CBQ,j)=${CUT(CBQ,,1-$[${i} - 1])}-${SaveCBQ},${i})

same => n,NOOP([CBQ:1]= ${CBQ:1} :: [CBQ:0:-1]=${CBQ:0:-1} :: [CBQ:-1]=${CBQ:-1})

same => n,EXECIF($["${CBQ:-1}" == "-"]?SET(CBQ=${CBQ:0:-1}))

same => n,EXECIF($["${CBQ:0:1}" == "-"]?SET(CBQ=${CBQ:1}))

same => n,SET(DB(call-back/${CALLERID(num)})=${CBQ})

same => n,Dial(SIP/${DIALME})

same => n(hangup),Hangup()

[register-callback]

exten => s,1,SET(CALLERID(num)=${RAND(100,110)})

same => n,NOOP(Caller ${CALLERID(num)} Registering Call-Back for User ${DEST})

same => n,NOOP(do some call-back tricks here)

same => n,SET(CBQ=${DB(call-back/${DEST})})

same => n,GOTOIF($["${CBQ}" == ""]?first:sec)

same => n(first),Set(DB(call-back/${DEST})=${CALLERID(num)})

same => n,GOTO(jump)

same => n(sec),Macro(duplicate-check,${CALLERID(num)})

same => n,GOTOIF($["${RESULT}" == "1"]?jump)

same => n,Set(DB(call-back/${DEST})=${CALLERID(num)}-${CBQ})

same => n(jump),NOOP(Playback(thanks-willb-called-shortly))

same => n,Hangup()

exten => i,1,GOTO(s,1)

[macro-duplicate-check]

exten => s,1,NOOP(${CBQ} Checked for Duplicate ${ARG1})

exten => s,n,SET(COUNT=${FIELDQTY(CBQ,-)})

exten => s,n,SET(ARRAY(i,RESULT)=1,0)

exten => s,n,WHILE($["${i}" <= "${COUNT}"])

exten => s,n,NOOP(${CUT(CBQ,,${i})} == ${ARG1})

exten => s,n,EXECIF($["${CUT(CBQ,,${i})}" == "${ARG1}"]?GOTO(found):SET(i=$[${i} + 1]))

exten => s,n,Endwhile()

exten => s,n,MacroExit()

exten => s,n(found),SET(RESULT=1)

exten => s,n,MacroExit()