I have to invoke .NET SDK through an existing GATEWAY mapped to our Genesys API(https://api.mypurecloud.com). How can I add GATEWAY parameter to our SDKs?
Largely depends on the specifics of the gateway, but you can accomplish that a few ways.
You can directly interact with the underlying SDK's underlying RestClient via - Configuration.Default.ApiClient.RestClient
That means if your gateway is able to be represented as an IProxy interface you can just create that reference and assign it via
Configuration.Default.ApiClient.RestClient.Proxy = new WebProxy( "your adress");
That's a very lose example, you probably need to actually create, configure and assign a more detailed object.
If it's more complicated and you need to rewrite the whole URL you can create your own version of RestClient that overrides the execute command to rewrite the URL to include your gateway pattern. The implementation of your own overrides is only about 250 lines but still annoying and comes with risks of missing changes to the underlying defaults from the SDK.
I was able to go through the GATEWAYS using RestClient and RestRequests. But I am trying to find a way through SDK API's. Because SDK APIs comes with the inbuilt response structure which can be used directly.
I did not suggest using rest client directly yourself.
The SDK relies on a rest client it exposes to end users for extension.
A suitably skilled programmer can modify the behavior of that rest client, directly or by creating their own replacement, so the SDK does what you need to do in it's requests without changing how the SDK works.