I believe the code below is how I would make a call to my AWS Lambda function. Users log into the site with Cognito. Would I somehow get credentials from the User.Identity or would I use an access key/secret here?

AmazonLambdaClient alc = new AmazonLambdaClient(credentials);
Amazon.Lambda.Model.InvokeRequest ir = new Amazon.Lambda.Model.InvokeRequest();
ir.FunctionName = "arn:aws:lambda:us-east-1:xxxx:function:get-data";
ir.Payload = "";
var res = alc.InvokeAsync(ir);