how do you you register port to dissector if port is broadcasted over the MDNS query SRV records?

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I have added some code in MDNS dissector to check for that specific service and reg dissector handle to that port in dns srv records , but i dont think it will be acceptable to open source community , i know i need to use conversations but i dont quit get how t do that like if i create conversation in MDNS SRV records or in my dissector file can someone elaborate here and please suggest some proto which has same behaviour. this is in SRV records service: __foo._udp`` port: 34561 then based on service type i register my dissector handle with dissector_add_uint('udp.port', port, foo_handle)