public Startup(IHostingEnvironment env)
{
var builder = new ConfigurationBuilder()
.SetBasePath(Path.Combine(Directory.GetCurrentDirectory(), Conf))
.AddJsonFile(AppSettingsJson, optional: true, reloadOnChange: true)
.AddEnvironmentVariables();
Configuration = builder.Build();
ConfigurationRoot = builder.Build();
ConfigurationRoot.Bind(AppSettings);
}
/// <summary>Attempts to bind the given object instance to configuration section value by FileConfigurationProvider.</summary>
/// <param name="options">The object to bind.</param>
/// <param name="value">The value to bind.</param>
/// <param name="provider">The <see cref="T:FileConfigurationProvider" /> to load the value.</param>
public static void Bind <TOptions>([NotNull] TOptions options, string value, [NotNull] FileConfigurationProvider provider) where TOptions : class
{
if (options == null)
{
throw new ArgumentNullException(nameof(options));
}
if (string.IsNullOrWhiteSpace(value))
{
return;
}
if (provider == null)
{
throw new ArgumentNullException(nameof(provider));
}
var root = new ConfigurationRoot(new List <IConfigurationProvider> {
provider
});
using (var stream = new MemoryStream(Encoding.UTF8.GetBytes(value)))
provider.Load(stream);
root.Bind(options);
}
private void Init()
{
//problems:
//a: if multiple providers provide values for a collection, the values get added
//doubleMerge: when having Config inside Config, Bind will be executed twice
// Bind binds recursive, so the subConfig Constructor calls Init (bind#1) and then binds again below (bind#2)
//c: On the init call from Change token, existing element will be bound again
//d: setting classes will be registered as singletons, but when using sub settings is used,
// you will end up with separate instances despite registrations. To handle this correctly,
// sub settings would need to be resolved from ioc, and set in this instance.
#region doubleMerge
//create sub Settings by us here, so they will not get double bound here
//after binding below, the constructor of the sub class will bind, and then the binding here will bind it again
//so with merge behaviour of binding, values of array will be doubled
//https://github.com/dotnet/runtime/issues/46988
//idea for doubleMerge workaround:
// construct sub configs before binding (has correct values) and replace here after binding.
var subSettings = new Dictionary <PropertyInfo, object>();
foreach (var propertyInfo in GetType().GetProperties()
.Where(x => x.CanRead && x.CanWrite)
.Where(x => typeof(SettingsBase).IsAssignableFrom(x.PropertyType)))
{
var subSetting = Activator.CreateInstance(propertyInfo.PropertyType);
subSettings.Add(propertyInfo, subSetting);
}
#endregion
var sectionPath = GetType().GetSectionPath();
//read current values from IConfiguration
if (string.IsNullOrWhiteSpace(sectionPath))
{
ConfigurationRoot.Bind(this);
}
else
{
ConfigurationRoot.GetSection(sectionPath).Bind(this);
}
//ApplyReadTransformations
foreach (var transformation in ConfigurationOptions.StringTransformations)
{
StringTransformerBase.TransformObject(this, ConfigurationRoot, transformation.PerformReadTransformation);
}
#region doubleMerge
//set back sub settings
foreach (var pair in subSettings)
{
pair.Key.SetValue(this, pair.Value);
}
#endregion
}