feat: AddValidatedOptions bind+validate+ValidateOnStart

2026-06-01 09:31:14 -04:00
parent 563cf44c60
commit e191893738
2 changed files with 83 additions and 0 deletions
@@ -0,0 +1,36 @@
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Options;
+
+namespace ZB.MOM.WW.Configuration;
+
+/// <summary>DI extensions for binding-and-validating an options section in one call.</summary>
+public static class ServiceCollectionExtensions
+{
+    /// <summary>
+    /// Binds <typeparamref name="TOptions"/> to the configuration section at
+    /// <paramref name="sectionPath"/>, registers <typeparamref name="TValidator"/> as its
+    /// <see cref="IValidateOptions{TOptions}"/>, and enables <c>ValidateOnStart</c> so a bad
+    /// configuration fails fast at host startup rather than on first use.
+    /// </summary>
+    /// <typeparam name="TOptions">The options type to bind and validate.</typeparam>
+    /// <typeparam name="TValidator">The validator registered for <typeparamref name="TOptions"/>.</typeparam>
+    /// <param name="services">The service collection.</param>
+    /// <param name="configuration">The configuration to bind from.</param>
+    /// <param name="sectionPath">The configuration section path (e.g. <c>"ScadaBridge:Cluster"</c>).</param>
+    /// <returns>The <see cref="OptionsBuilder{TOptions}"/> for further chaining.</returns>
+    public static OptionsBuilder<TOptions> AddValidatedOptions<TOptions, TValidator>(
+        this IServiceCollection services, IConfiguration configuration, string sectionPath)
+        where TOptions : class
+        where TValidator : class, IValidateOptions<TOptions>
+    {
+        ArgumentNullException.ThrowIfNull(services);
+        ArgumentNullException.ThrowIfNull(configuration);
+        ArgumentException.ThrowIfNullOrWhiteSpace(sectionPath);
+
+        services.AddSingleton<IValidateOptions<TOptions>, TValidator>();
+        return services.AddOptions<TOptions>()
+            .Bind(configuration.GetSection(sectionPath))
+            .ValidateOnStart();
+    }
+}
@@ -0,0 +1,47 @@
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Options;
+using ZB.MOM.WW.Configuration;
+
+namespace ZB.MOM.WW.Configuration.Tests;
+
+public sealed class AddValidatedOptionsTests
+{
+    private sealed class NodeOptions { public int Port { get; set; } public string? Name { get; set; } }
+
+    private sealed class NodeValidator : OptionsValidatorBase<NodeOptions>
+    {
+        protected override void Validate(ValidationBuilder v, NodeOptions o)
+        {
+            v.Port(o.Port, "Node:Port");
+            v.Required(o.Name, "Node:Name");
+        }
+    }
+
+    private static IHost BuildHost(Dictionary<string, string?> config)
+    {
+        var builder = Host.CreateApplicationBuilder();
+        builder.Configuration.AddInMemoryCollection(config);
+        builder.Services.AddValidatedOptions<NodeOptions, NodeValidator>(builder.Configuration, "Node");
+        return builder.Build();
+    }
+
+    [Fact]
+    public async Task Bad_config_throws_at_startup()
+    {
+        using var host = BuildHost(new() { ["Node:Port"] = "0", ["Node:Name"] = "" });
+        await Assert.ThrowsAsync<OptionsValidationException>(() => host.StartAsync());
+    }
+
+    [Fact]
+    public async Task Good_config_starts_and_binds()
+    {
+        using var host = BuildHost(new() { ["Node:Port"] = "8080", ["Node:Name"] = "central" });
+        await host.StartAsync();
+        var opts = host.Services.GetRequiredService<IOptions<NodeOptions>>().Value;
+        Assert.Equal(8080, opts.Port);
+        Assert.Equal("central", opts.Name);
+        await host.StopAsync();
+    }
+}