[asterisk-users] Prefix/Suffix/StripLSD/StripMSD gone?

[Paul Schenkeveld]

On Tue, Nov 21, 2006 at 01:18:47PM -0600, Don Pobanz wrote:
> >Have Prefix, Suffix, StripLSD and StripMSD disappeared?
> 
> yes
> 
> >Is there another way to manipulate the current extention 
> >an continue at the appropriate line in the current context?
> 
> see substrings and String Concatenation under variables 
> http://www.voip-info.org/wiki-Asterisk+variables

Ok, but if I use this to change EXTEN, asterisk will continue to
process statements in the same context based on the original value
of EXTEN.

What I tried to accomplish is this:

    112     emergency call to be routed through 
    _0.     outside line calls using LCR rules in extensions.conf
    _90.    force outside calls through ISDN
    _91.    force outside calls through provider 1
    _92.    force outside calls through provider 2

Note that in many countries here in Europe 0 is used for outside lines,
06 are cellphone numbers, 0800 tollfree, 09XX payed services and 112 is
the emergency number.

So what I had thought up is:

    [globals]
    PROV_EMERG=90   ; Emergency calls go out via ISDN
    PROV_INT=91     ; Provider 1 for international calls
    PROV_NAT=92     ; Provider 2 for national calls
    PROV_0800=90    ; Tollfree calls go out via ISDN
    PROV_09XX=90    ; Payed services calls go out via ISDN
    PROV_06=90      ; Cellphone calls go out via ISDN

    [outgoing]
    ; Allow emergency calls with or without 0 for outside lines
    exten => 112,1,Prefix(0)

    ; Emergency calls always via ISDN
    exten => 0112,1,NoOp(Emergency call)
    exten => 0112,n,Prefix(${PROV_EMERG})

    ; International calls
    exten => _00.,1,NoOp(International call to ${EXTEN})
    exten => _00.,n,Prefix(${PROV_INT})

    ; National calls (always 10 digits)
    exten => _0[1-57]XXXXXXXX,1,NoOp(National call to ${EXTEN})
    exten => _0[1-57]XXXXXXXX,n,Prefix(${PROV_NAT})

    ; Cell phone calls (always 10 digits)
    exten => _06XXXXXXXX,1,NoOp(06 call to ${EXTEN})
    exten => _06XXXXXXXX,n,Prefix(${PROV_06})

    ; Tollfree calls (variable length)
    exten => _0800.,1,NoOp(0800 call to ${EXTEN})
    exten => _0800.,n,Prefix(${PROV_0800})

    ; Payed services (variable length)
    exten => _09XX.,1,NoOp(0800 call to ${EXTEN})
    exten => _09XX.,n,Prefix(${PROV_09XX})

    ; Out via ISDN
    exten => _90.,1,NoOp(Routing via ISDN)
    exten => _90.,n, ...

    ; Out via provider 1
    exten => _91.,1,NoOp(Routing via provider 1)
    exten => _91.,n, ...

    ; Out via provider 1
    exten => _92.,1,NoOp(Routing via provider 2)
    exten => _92.,n, ...

    ; Out via provider 1
    exten => _93.,1,NoOp(Routing via provider 3)
    exten => _93.,n, ...

    exten => _X,1,Congestion()

According to the online docs and the O'Reilly book, after a Prefix()
asterisk continues at the first match of the new value of EXTEN.  With
SetVar I see that asterisk continues with the next priority of the old
EXTEN value.

Is there another way to accomplish the above?

Note that originating a call to a provider sometimes needs more than
just a Dial() application.  For example, one of my providers wants
customers to do round-robin and failover voice routing:

    [macro-safedial]
    exten = s,1,Dial(${ARG1},${ARG2},${ARG3},${ARG4})
    exten = s,n,Goto(s-${DIALSTATUS},1)
    exten = s-CANCEL,1,Hangup
    exten = s-NOANSWER,1,GotoIf($["${DIALEDTIME}" = "0"]?out)
    exten = s-NOANSWER,n,Hangup
    exten = s-NOANSWER,n(out),Verbose(1,Need failover for "${ARG1}")
    exten = s-BUSY,1,Busy
    exten = s-CHANUNAVAIL,1,Verbose(1,Need failover for "${ARG1}")
    exten = s-CONGESTION,1,Congestion()
    exten = _s-.,1,Congestion()
    exten = s-,1,Congestion()

    [route-pstn]
    exten = _X.,1,Random(33:switch03)
    exten = _X.,n,Random(50:switch02)
    exten = _X.,n(switch01),Macro(safedial,IAX2/switch01/${EXTEN})
    exten = _X.,n,Macro(safedial,IAX2/switch02/${EXTEN})
    exten = _X.,n,Macro(safedial,IAX2/switch03/${EXTEN})
    exten = _X.,n,Goto(out)
    exten = _X.,n(switch02),Macro(safedial,IAX2/switch02/${EXTEN})
    exten = _X.,n,Macro(safedial,IAX2/switch03/${EXTEN})
    exten = _X.,n,Macro(safedial,IAX2/switch01/${EXTEN})
    exten = _X.,n,Goto(out)
    exten = _X.,n(switch03),Macro(safedial,IAX2/switch03/${EXTEN})
    exten = _X.,n,Macro(safedial,IAX2/switch01/${EXTEN})
    exten = _X.,n,Macro(safedial,IAX2/switch02/${EXTEN})
    exten = _X.,n(out),Congestion()
    exten = i,1,Congestion()

-- Paul Schenkeveld