My use case is such that I want to be able to send a SIP MESSAGE destined for a single username to multiple users. In order to be able to map that target username to multiple usernames, I tried using rtjson and evapi/http (to generate the routing json), but none of them worked.

Is it the right approach? Is there any other way to programmatically generate multiple targets for SIP request? I am familiar with dynamic routing but I need more flexibility.

Initially, I tried sending the request to a different username but that didn't work and got the following message in the http async result route.

kamailio    | 19(25) ERROR: nathelper [nathelper.c:1461]: sdp_1918(): Unable to parse sdp body
kamailio    | 19(25) NOTICE: <core> [core/kemi.c:124]: sr_kemi_core_notice(): In evapi msg branch
kamailio    | 28(34) NOTICE: {2 6661 MESSAGE q6hikd6tumsr1dh35kvj} <core> [core/kemi.c:124]: sr_kemi_core_notice(): In evapi reply branch 


The message was received on the originally requested to user and also $tu still points to the original user instead of the new user even after executing the following code.

KSR.rtjson.init_routes(response);
KSR.rtjson.push_routes();
KSR.nathelper.fix_nated_contact(); 

In http response, I receive the following and don't see any rtjson errors when init_routes is executed on it.

{"version":"1.0","routing":"parallel","routes":[{"headers":{"from":{"display":"test_1","uri":"sip:test_1@test.com:9908"},"to":{"display":"test_4","uri":"sip:test_4@test.com:9908"},"extra":""},"branch_flags":8,"fr_timer":5000,"fr_inv_timer":30000}]}

Please note that the request was sent to test_2@test.com. I have tried other combinations of above but nothing works.

I have already searched on Google and read relevant articles and blog posts. 

Thanks
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