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Dialplan Configuration

I'm using FreeSWITCH mostly as a PBX and found I need a callgroup (call group) configuration similar to one in Asterisk. Default examples show intercepting a last global call, but with the help of "db" application, one can easily configure "intercept" to work only inside a same callgroup. FreeSWITCH sets "uuid" variable for a every call. It is a unique variable representing a call. We check for the called user's "callgroup" variable value, and put a value of "uuid" variable of every call to a wanted extension in a separate database named after "callgroup" variable.

 <action application="set" data="called_party_callgroup=${user_data(${dialed_ext}@${domain} var callgroup)}"/>
 <action application="db" data="insert/last_dial/${called_party_callgroup}/${uuid}"/>
 <action application="bridge" data="user/${dialed_ext}@$${domain}"/>

Extension to call which checks for user's "callgroup" variable value, and intercepts the call which uuid is extracted from the db:

 <extension name="group-intercept">
   <condition field="destination_number" expression="^\*8$">
     <action application="answer"/>
     <action application="intercept" data="${db(select/last_dial/${callgroup})}"/>
     <action application="sleep" data="2000"/>
   </condition>
  </extension>

Directory configuration

We add "callgroup" variable inside user's directory xml file.

 <user id="1001" mailbox="1001">
   <params>
     <param name="password" value="1234"/>
     <param name="vm-password" value="1001"/>
   </params>
   <variables>
     <variable name="accountcode" value="1001"/>
     <variable name="user_context" value="default"/>
     <variable name="effective_caller_id_name" value="Extension 1001"/>
     <variable name="effective_caller_id_number" value="1001"/>
     <variable name="callgroup" value="1"/>
   </variables>
 </user>