BindingExtensions.g.cs

// <auto-generated/>
#nullable enable
#pragma warning disable CS0612, CS0618 // Suppress warnings about [Obsolete] member usage in generated code.

namespace System.Runtime.CompilerServices
{
    using System;
    using System.CodeDom.Compiler;

    [GeneratedCode("Microsoft.Extensions.Configuration.Binder.SourceGeneration", "8.0.8.47906")]
    [AttributeUsage(AttributeTargets.Method, AllowMultiple = true)]
    file sealed class InterceptsLocationAttribute : Attribute
    {
        public InterceptsLocationAttribute(string filePath, int line, int column)
        {
        }
    }
}

namespace Microsoft.Extensions.Configuration.Binder.SourceGeneration
{
    using Microsoft.Extensions.Configuration;
    using Microsoft.Extensions.DependencyInjection;
    using Microsoft.Extensions.Options;
    using System;
    using System.CodeDom.Compiler;
    using System.Collections.Generic;
    using System.Globalization;
    using System.Runtime.CompilerServices;

    [GeneratedCode("Microsoft.Extensions.Configuration.Binder.SourceGeneration", "8.0.8.47906")]
    file static class BindingExtensions
    {
        #region IServiceCollection extensions.
        /// <summary>Registers a configuration instance which TOptions will bind against.</summary>
        [InterceptsLocation(@"C:\Users\kohe-hakoishi\source\repos\WebApplication1\WebApplication1\Program.cs", 7, 18)]
        public static IServiceCollection Configure<TOptions>(this IServiceCollection services, IConfiguration config) where TOptions : class
        {
            return Configure<TOptions>(services, string.Empty, config, configureOptions: null);
        }

        /// <summary>Registers a configuration instance which TOptions will bind against.</summary>
        public static IServiceCollection Configure<TOptions>(this IServiceCollection services, string? name, IConfiguration config, Action<BinderOptions>? configureOptions) where TOptions : class
        {
            if (services is null)
            {
                throw new ArgumentNullException(nameof(services));
            }

            if (config is null)
            {
                throw new ArgumentNullException(nameof(config));
            }

            OptionsServiceCollectionExtensions.AddOptions(services);
            services.AddSingleton<IOptionsChangeTokenSource<TOptions>>(new ConfigurationChangeTokenSource<TOptions>(name, config));
            return services.AddSingleton<IConfigureOptions<TOptions>>(new ConfigureNamedOptions<TOptions>(name, instance => BindCoreMain(config, instance, typeof(TOptions), configureOptions)));
        }
        #endregion IServiceCollection extensions.

        #region Core binding extensions.
        private readonly static Lazy<HashSet<string>> s_configKeys_MyOptions = new(() => new HashSet<string>(StringComparer.OrdinalIgnoreCase) { "X" });

        public static void BindCoreMain(IConfiguration configuration, object instance, Type type, Action<BinderOptions>? configureOptions)
        {
            if (instance is null)
            {
                return;
            }

            if (!HasValueOrChildren(configuration))
            {
                return;
            }

            BinderOptions? binderOptions = GetBinderOptions(configureOptions);

            if (type == typeof(MyOptions))
            {
                var temp = (MyOptions)instance;
                BindCore(configuration, ref temp, defaultValueIfNotFound: false, binderOptions);
                return;
            }

            throw new NotSupportedException($"Unable to bind to type '{type}': generator did not detect the type as input.");
        }

        public static void BindCore(IConfiguration configuration, ref MyOptions instance, bool defaultValueIfNotFound, BinderOptions? binderOptions)
        {
            ValidateConfigurationKeys(typeof(MyOptions), s_configKeys_MyOptions, configuration, binderOptions);
        }

        public static MyOptions InitializeMyOptions(IConfiguration configuration, BinderOptions? binderOptions)
        {
            int X = default;
            if (configuration["X"] is string value1)
            {
                X = ParseInt(value1, () => configuration.GetSection("X").Path);
            }
            else
            {
                throw new InvalidOperationException("Cannot create instance of type '<global namespace>.MyOptions' because parameter 'X' has no matching config. Each parameter in the constructor that does not have a default value must have a corresponding config entry.");
            }

            return new MyOptions(X)
            {
                X = X,
            };
        }


        /// <summary>If required by the binder options, validates that there are no unknown keys in the input configuration object.</summary>
        public static void ValidateConfigurationKeys(Type type, Lazy<HashSet<string>> keys, IConfiguration configuration, BinderOptions? binderOptions)
        {
            if (binderOptions?.ErrorOnUnknownConfiguration is true)
            {
                List<string>? temp = null;
        
                foreach (IConfigurationSection section in configuration.GetChildren())
                {
                    if (!keys.Value.Contains(section.Key))
                    {
                        (temp ??= new List<string>()).Add($"'{section.Key}'");
                    }
                }
        
                if (temp is not null)
                {
                    throw new InvalidOperationException($"'ErrorOnUnknownConfiguration' was set on the provided BinderOptions, but the following properties were not found on the instance of {type}: {string.Join(", ", temp)}");
                }
            }
        }

        public static bool HasValueOrChildren(IConfiguration configuration)
        {
            if ((configuration as IConfigurationSection)?.Value is not null)
            {
                return true;
            }
            return AsConfigWithChildren(configuration) is not null;
        }

        public static IConfiguration? AsConfigWithChildren(IConfiguration configuration)
        {
            foreach (IConfigurationSection _ in configuration.GetChildren())
            {
                return configuration;
            }
            return null;
        }

        public static BinderOptions? GetBinderOptions(Action<BinderOptions>? configureOptions)
        {
            if (configureOptions is null)
            {
                return null;
            }
        
            BinderOptions binderOptions = new();
            configureOptions(binderOptions);
        
            if (binderOptions.BindNonPublicProperties)
            {
                throw new NotSupportedException($"The configuration binding source generator does not support 'BinderOptions.BindNonPublicProperties'.");
            }
        
            return binderOptions;
        }

        public static int ParseInt(string value, Func<string?> getPath)
        {
            try
            {
                return int.Parse(value, NumberStyles.Integer, CultureInfo.InvariantCulture);
            }
            catch (Exception exception)
            {
                throw new InvalidOperationException($"Failed to convert configuration value at '{getPath()}' to type '{typeof(int)}'.", exception);
            }
        }
        #endregion Core binding extensions.
    }
}

Program.cs

var builder = WebApplication.CreateBuilder(args);

builder.Services.Configure<MyOptions>(builder.Configuration);

var app = builder.Build();

public record MyOptions(int X);