Entity Framework Command Duration Interceptor - Outputs as a response header.

To add the interceptor to DbContext call the AddInterceptors method when configuring your DbContext.

using EFDurationInterceptor;
...
services
  .AddDbContext<NvmContext>((provider, options) => options
  .UseSqlServer(connectionString)
  .AddInterceptors(provider.GetRequiredService<DurationDbInterceptor>())); 

A value is added to the response headers for both the duration setting up connections and the duration executing commands.