Custom appsettings.json is not loaded - asp.net

Question

I have an .net core 2.0 application, having multiple appsettings files. I have appsettings.json, appsettings.Development.json and a custom appsettings.Secure.json.
//appSettings.json
{
"AzureAd" : {
"ClientId" : "CID"
}
}
//appSettings.Development.json
{
"AzureAd" : {
"Random" : "random2"
}
}
//appSettings.Secure.json
{
"AzureAd" : {
"ClientSecret" : "CSECRET"
}
}
I always want my appSettings.Secure.json configs to be loaded. Here's how the json files are configured.
var config = new ConfigurationBuilder()
.SetBasePath(Directory.GetCurrentDirectory())
.AddJsonFile("appSettings.json", optional : false)
.AddJsonFile("appSettings.Development.json")
.AddJsonFile("appsettings.Secure.json", optional: true, reloadOnChange: true)
.AddEnvironmentVariables()
.Build();
The problem is that my "AzureAd:ClientSecret" gets loaded in the config (gets listed in the Providers section of the config object) but when I inject IOption, the ClientSecret property is null.
AzureAdOptions is the class to which the properties are mapped, and it's registered as follows:
services.Configure<AzureAdOptions>(Configuration.GetSection("AzureAd"));

Answer 1

JSON is not secure in any way, especially so considering that this is likely being committed to your source control.
The appsettings.json file is for generic, environment in-specific config. Then, you should have appsettings.{environment}.json files for each environment, but still no secrets should go in any of these files. In development, you can utilize User Secrets to store your secrets. In production, you should be using something like Azure Key Vault and/or environment variables for secrets.
Long and short, your appsettings.Secure.json file should not exist in the first place. It's not an environment and it's not secure.