why not access it as global variable like

session:getVariable("caller_id_name"); 

and pass it to some variable or you can take help from following snippet of code from 

 function randomize()
api = freeswitch.API();
seed = tonumber(api:execute("global_getvar", "randomseed"));
if seed == 12345678 or seed == "" or seed == nil then
seed = os.time();
end
math.randomseed(seed);
seed = math.random(1,999999)
api:execute("global_setvar", "randomseed=" .. seed)
end

 I have taken it from
 https://wiki.freeswitch.org/wiki/Fakecall_responder


> Date: Sun, 31 May 2015 00:41:06 +0200
> From: dragic.dusan@gmail.com
> To: freeswitch-users@lists.freeswitch.org
> Subject: Re: [Freeswitch-users] Need help with lua called from dial plan - How to delimit arguments?
>
> Use single quotes (but Giovanni's suggestion is the way to go).
>
> On 30 May 2015 at 22:21, Jim Lynch <jim@k4gvo.com> wrote:
> > I have a line in my dialplan that looks like this:
> > <action application="lua" data="cid.lua ${caller_id_name}
> > ${caller_id_number}" />
> >
> > However when the program is executed and the caller_id_name has a space
> > in it, the number gets lost.
> > I can't figure out a way to add delimiters that get passed to the
> > shell. None of these work:
> >
> > <action application="lua" data="cid.lua \"${caller_id_name}\"
> > \"${caller_id_number}\"" />
> > or
> > <action application="lua" data="cid.lua ''${caller_id_name}''
> > ''${caller_id_number}''" />
> > or
> > <action application="lua" data="cid.lua \"\"${caller_id_name}\"\"
> > \"\"${caller_id_number}\"\"" />
> >
> > None of those work. The quotes are all stripped off when running this test
> >
> > lua file:
> > tmp_file = "/tmp/cidtest.txt";
> > local file = assert(io.open(tmp_file, "a"));
> > local m_name=argv[1];
> > local m_number=argv[2];
> > file:write("j cid is ",m_name," number is ",m_number,"\n");
> >
> > Any suggestions?
> >
> > Thanks,
> > Jim.
> >
> > _________________________________________________________________________
> > Professional FreeSWITCH Consulting Services:
> > consulting@freeswitch.org
> > http://www.freeswitchsolutions.com
> >
> > Official FreeSWITCH Sites
> > http://www.freeswitch.org
> > http://confluence.freeswitch.org
> > http://www.cluecon.com
> >
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>
>
>
> --
> Dušan Dragić
>
> _________________________________________________________________________
> Professional FreeSWITCH Consulting Services:
> consulting@freeswitch.org
> http://www.freeswitchsolutions.com
>
> Official FreeSWITCH Sites
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>
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