/// <summary>
/// Adds a new configuration source, retrieves the provider for the source, and
/// adds a change listener that triggers a reload of the provider whenever a change
/// is detected.
/// </summary>
/// <param name="source">The configuration source to add.</param>
/// <returns>The same <see cref="IConfigurationBuilder"/>.</returns>
public IConfigurationBuilder Add(IConfigurationSource source)
{
if (source == null)
{
throw new ArgumentNullException(nameof(source));
}
// Ads this source and its associated provider to the source
// and provider references in this class. We make sure to load
// the data from the provider so that values are properly initialized.
_sources.Add(source);
var provider = source.Build(this);
provider.Load();
// Add a handler that will detect when the the configuration
// provider has reloaded data. This will invoke the RaiseChanged
// method which maps changes in individual providers to the change
// token on the WebAssemblyHostConfiguration object.
_changeTokenRegistrations.Add(ChangeToken.OnChange(() => provider.GetReloadToken(), () => RaiseChanged()));
// We keep a list of providers in this class so that we can map
// set and get methods on this class to the set and get methods
// on the individual configuration providers.
_providers.Add(provider);
return(this);
}
public IConfigurationProvider Build(IConfigurationBuilder builder)
{
if (_provider != null)
{
return(_provider);
}
return(_provider = _source.Build(builder));
}
public IConfigurationProvider Build(IConfigurationBuilder builder)
{
return(new HookConfigurationProvider(source.Build(builder), hook));
}
