Lua Intercom example

About

Calls a defined list of extensions that are not currently active in a call then auto answers the call.

Dialplan entry

 <extension name="intercom" >
    <condition field="destination_number" expression="^\*468$">
        <action application="set" data="sounds_dir=/usr/local/freeswitch/sounds"/>
        <action application="set" data="pin_number=1234"/>
        <action application="set" data="caller_id_name=intercom"/>
        <action application="set" data="extension_list=1002,1003"/>
        <action application="set" data="caller_id_number=5551231234"/>
        <action application="lua" data="intercom.lua"/>
    </condition>
 </extension>

Script intercom.lua

 --	intercom.lua
 --	Part of FusionPBX
 --	Copyright (C) 2010 Mark J Crane <markjcrane@fusionpbx.com>
 --	All rights reserved.
 --
 --	Redistribution and use in source and binary forms, with or without
 --	modification, are permitted provided that the following conditions are met:
 --
 --	1. Redistributions of source code must retain the above copyright notice,
 --	   this list of conditions and the following disclaimer.
 --
 --	2. Redistributions in binary form must reproduce the above copyright
 --	   notice, this list of conditions and the following disclaimer in the
 --	   documentation and/or other materials provided with the distribution.
 --
 --	THIS SOFTWARE IS PROVIDED ``AS IS AND ANY EXPRESS OR IMPLIED WARRANTIES,
 --	INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 --	AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 --	AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 --	OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 --	SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 --	INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 --	CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 --	ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 --	POSSIBILITY OF SUCH DAMAGE.
 
 pin_number = "";
 max_tries = "3";
 digit_timeout = "3000";
 
 function trim (s)
 	return (string.gsub(s, "^%s*(.-)%s*$", "%1"))
 end
 
 function explode ( seperator, str ) 
 	local pos, arr = 0, {}
 	for st, sp in function() return string.find( str, seperator, pos, true ) end do -- for each divider found
 		table.insert( arr, string.sub( str, pos, st-1 ) ) -- attach chars left of current divider
 		pos = sp + 1 -- jump past current divider
 	end
 	table.insert( arr, string.sub( str, pos ) ) -- attach chars right of last divider
 	return arr
 end
 
 if ( session:ready() ) then
 	session:answer();
 	pin_number = session:getVariable("pin_number");
 	domain_name = session:getVariable("domain_name");
 	sounds_dir = session:getVariable("sounds_dir");
 	extension_list = session:getVariable("extension_list");
 	caller_id_name = session:getVariable("caller_id_name");
 	caller_id_number = session:getVariable("caller_id_number");
 	extension_table = explode(",",extension_list);
 
 	--if the pin number is provided then require it
 	if (pin_number) then
 		min_digits = string.len(pin_number);
 		max_digits = string.len(pin_number);
 		digits = session:playAndGetDigits(min_digits, max_digits, max_tries, digit_timeout, "#", sounds_dir.."/custom/please_enter_the_pin_number.wav", "", "\\d+");
 		if (digits == pin_number) then
 			--pin is correct
 		else
 			session:streamFile(sounds_dir.."/custom/your_pin_number_is_incorect_goodbye.wav");
 			session:hangup("NORMAL_CLEARING");
 			return;
 		end
 	end
 
 	api = freeswitch.API();
 	for index,value in pairs(extension_table) do
 		extension_status = "show channels like "..value.."@"..domain_name;
 		reply = api:executeString(extension_status);
 		reply = trim(reply);
 		if (reply == "0 total.") then
 			--freeswitch.consoleLog("NOTICE", "extension "..value.." available\n");
 			cmd_string = "bgapi originate {sip_auto_answer=true,absolute_codec_string=PCMU,hangup_after_bridge=false,origination_caller_id_name="..caller_id_name..",origination_caller_id_number="..caller_id_number.."}user/"..value.."@"..domain_name.." conference:intercom@default+flags{mute} inline";
 			--freeswitch.consoleLog("NOTICE", "cmd_string "..cmd_string.."\n");
 			api:executeString(cmd_string);
 		else
 			--call status busy
 		end
 	end
 
 	--send main call to the conference room
 		session:execute("conference", "intercom@default+flags{endconf}");
 end