[asterisk-users] howto store local exchange prefixes ?

[Barry L. Kline]

sean darcy wrote:

> Maybe I've not explained this correctly. I know, or can look up, the 40+ 
> local exchanges that are local. I can parse the dial EXTEN to determine 
> the exchange. I can check the exchange against a DB. I want to determine 
> which exchanges are "local". I do not want to store an exchange dialed 
> by a user.

I didn't explain myself very well.

My Asterisk system sits between the PSTN and a legacy PBX.  Asterisk
answers the call and among other things, prompts for an extension
number.   I needed to know if the extension entered is valid before
sending the call on to the old PBX.  I simply have a lookup subroutine
to validate the extension.

My code for looking up the validity of their entry is:

exten => _[123]XX,1,Verbose(1,${CALLERID(all)} requested extension
${EXTEN});
exten => _[123]XX,n,Gosub(validate-extension,s,1(${EXTEN}));
exten => _[123]XX,n,Goto(extension-${GOSUB_RETVAL});
exten => _[123]XX,n(extension-FOUND),Verbose(1,${CALLERID(all)} xfer to
${DB(${DB_IWATSU_EXTENSIONS}/${EXTEN})} at extension ${EXTEN});
exten => _[123]XX,n,macro(bridge-to-iwatsu,7${EXTEN});
exten => _[123]XX,n(extension-NOTFOUND),background(pbx-invalid);
exten => _[123]XX,n,WaitExten(5);



The lookup, which will initialize the AsteriskDB if necessary, is:

;
; This subroutine's purpose is to check the validity of an extension.
;
; Parameters:
;              ARG1 = Extension to check
; Returns:
;              FOUND or NOTFOUND
;
[validate-extension]
exten => s,1,Verbose(1,Checking validity of extension ${ARG1});
;
; Let's check to ensure that the database is loaded.  We'll do
; that by looking for extension 399, the Iwatsu master phone.
;
exten => s,n,GotoIf(${DB_EXISTS(${DB_IWATSU_EXTENSIONS}/399)}?search:load)
exten => s,n(load),DBdeltree(${DB_IWATSU_EXTENSIONS}); Clear all
existing entries
exten => s,n,Set(DB(${DB_IWATSU_EXTENSIONS}/120)='Rikki')
exten => s,n,Set(DB(${DB_IWATSU_EXTENSIONS}/121)='Terri')
exten => s,n,Set(DB(${DB_IWATSU_EXTENSIONS}/122)='CorpConf')
exten => s,n,Set(DB(${DB_IWATSU_EXTENSIONS}/123)='Linda')
exten => s,n,Set(DB(${DB_IWATSU_EXTENSIONS}/124)='Kim')
exten => s,n,Set(DB(${DB_IWATSU_EXTENSIONS}/125)='Nancy B')
exten => s,n,Set(DB(${DB_IWATSU_EXTENSIONS}/126)='Wayne')
...
;
; Extension 399 is the master extension for the Iwatsu
; and should always show up. It is used for testing
; the validity of the database in the dialplan.
;
exten => s,n,Set(DB(${DB_IWATSU_EXTENSIONS}/399)='MASTER')
;
; Search here
;
exten =>
s,n(search),GotoIf(${DB_EXISTS(${DB_IWATSU_EXTENSIONS}/${ARG1})}?found:notfound)
exten => s,n(found),Return(FOUND);
exten => s,n(notfound),Return(NOTFOUND);