app.Use(async (context, next) =>
{
var initialBody = context.Request.Body;
using (var bodyReader = new StreamReader(context.Request.Body))
{
string body = await bodyReader.ReadToEndAsync();
Console.WriteLine(body);
context.Request.Body = new MemoryStream(Encoding.UTF8.GetBytes(body));
await next.Invoke();
context.Request.Body = initialBody;
}
});