There is OpenApi hikcentral, Hik-connect API which will use their server( i dont like this) , hik partner pro API which enables configuration nodes(also their server) and ISUP(Device Gateway). I use Device gateway server where i register all the hikvision devices and then push to mobile phone apps.
But using anything that is on their end such as their servers, will results in hard limitation where you wont even guess.
I highly suggest creating your own server and not rely on them. As soon they change policy or some node/update, you will need to rush and update your service.