Pjsip database of registrations

[sami-hep]

So i am trying to always check whether the called extension is already registered in my database of registration before making the call otherwise then i would not make the call if not registered.
so earlier using chan_sip every registered endpoint was being added to /SIP/registry/EXTEN
then in my dialplan i would then check if this database exists or not and it was working so fine.
but when i moved to chan_psjip then every new registered endpoint would be added this way:

/registrar/contact/37200;@80316366e84eb97b6234ff873527f1e5: {“via_addr":“192.168.133.9”,“qualify_timeout”:“3.000000”,“call_id”:“U8vSqJ3wUy”,“reg_server”:"",“prune_on_boot”:“no”,“path”:"",“endpoint”:“37200”,“via_port”:“5060”,“authenticate_qualify”:“no”,“uri”:"sip:37200@192.168.133.9;transport=udp”,“qualify_frequency”:“0”,“user_agent”:“Linphonec/3.12.0 (belle-sip/1.6.3)”,“expiration_time”:“1583910539”,“outbound_proxy”:""}
/registrar/contact/37301;@46ba82eee12e5c52b156464ed1182ef9: {“via_addr”:“192.168.133.111”,“qualify_timeout”:“3.000000”,“call_id”:“mq0u3q2J6wdqJC0RiWkAzA…”,“reg_server”:"",“prune_on_boot”:“no”,“path”:"",“endpoint”:“37301”,“via_port”:“49142”,“authenticate_qualify”:“no”,“uri”:“sip:37301@192.168.133.111:49142;transport=UDP;rinstance=1a2057f2e9c432f5”,“qualify_frequency”:“0”,“user_agent”:“Z 5.3.8 rv2.9.30-mod”,“expiration_time”:“1583910361”,“outbound_proxy”:""}

this is how is checked before :
same => n,GotoIf({DB_EXISTS(SIP/Registry/{EXTEN:0:5})}?:not-found,1)

now i have to do this :
same => n,GotoIf({DB_EXISTS(registrar/contact/{EXTEN:0:5}(followed with this which i cant understand : @80316366e84eb97b6234ff873527f1e5))}?:not-found,1)

so my question is how could i edit how the registered contacts on pjsip would be stored as

registrar/contact/EXTEN like for example register/contact/37200
and not like this whole thing : /registrar/contact/37200;@80316366e84eb97b6234ff873527f1e5

or if i can not configure how database registrations could be stored
then how could then i check if database exists by checking only the non bold part /registrar/contact/37200**;@80316366e84eb97b6234ff873527f1e5** neglecting the bold part
since either ways my problem could be solved !
first is by re configuring how database for registration is stored and the other is by checking for not to whole part of the database entry

[jcolp]

Why do you check using this mechanism, instead of just doing the dial attempt or using DEVICE_STATE to check the device state?

[sami-hep]

by checking device state i could check if the called party is registered or not ?

[jcolp]

Yes. There is also the ChanIsAvail dialplan application[1]. Trying to Dial also works, as it will immediately fail if unregistered. That is what most people do.

[1] https://wiki.asterisk.org/wiki/display/AST/Asterisk+13+Application_ChanIsAvail

[sami-hep]

thanks i used DEVICE_STATE and i checked for 2 conditions UNAVILABLE and INVALID
it worked so fine.