System information

On Ubuntu:
$ sudo apt-get install libcurl4-openssl-dev
The Dialplan
The dialplan for our example IVR is very simple. The CURL() function will retrieve our
IP address from http://www.whatismyip.org, and then SayAlpha() will speak the results
to the caller:
exten => *764,1,Verbose(2, Run CURL to get IP address from whatismyip.org)
same => n,Answer()
same => n,Set(MyIPAddressIs=${CURL(http://www.whatismyip.org/)})
same => n,SayAlpha(${MyIPAddressIs})
same => n,Hangup()
The simplicity of this is impossibly cool. In a traditional IVR system, this sort of thing
could take days to program.
A Prompt-Recording Application
In Chapter 15 we created a simple bit of dialplan to record prompts. It was fairly limited
in that it only recorded one filename, and thus for each prompt the file needed to be
copied before a new prompt could be recorded. Here, we expand upon that to create
a complete menu for recording prompts:
[prompts]
exten => s,1,Answer
exten => s,n,Set(step1count=0) ; Initialize counters
; If we get no response after 3 times, we stop asking
same => n(beginning),GotoIf($[${step1count} > 2]?end)
same => n,Read(which,prompt-instructions,3)
same => n,Set(step1count=$[${step1count} + 1])
; All prompts must be 3 digits in length
same => n,GotoIf($[${LEN(${which})} < 3]?beginning)
same => n,Set(step1count=0) ; We have a successful response, so reset our counters
same => n,Set(step2count=0)
same => n(step2),Set(step2count=$[${step2count} + 1])
same => n,GotoIf($[${step2count} > 2]?beginning) ; No response after 3 tries
; If the file doesn't exist, then don't ask whether to play it
same => n,GotoIf($[${STAT(f,${which}.wav)} = 0]?recordonly)
same => n,Background(prompt-tolisten)
same => n(recordonly),Background(prompt-torecord)
same => n,WaitExten(10) ; Wait 10 seconds for a response
same => n,Goto(step2)
exten => 1,1,Set(step2count=0)
394 | Chapter 17: Interactive Voice Response