add support for configuring with custom MuninNodeOptions types

Author: smdn

src/Smdn.Net.MuninNode/Smdn.Net.MuninNode.DependencyInjection/IMuninServiceBuilderExtensions.cs

@@ -11,7 +11,9 @@ public static class IMuninServiceBuilderExtensions {
   /// <summary>
   /// Adds a <c>Munin-Node</c> to the <see cref="IMuninServiceBuilder"/> with default configurations.
   /// </summary>
-  /// <param name="builder">An <see cref="IMuninNodeBuilder"/> to build the <c>Munin-Node</c> to be added.</param>
+  /// <param name="builder">
+  /// An <see cref="IMuninServiceBuilder"/> that the built <c>Munin-Node</c> will be added to.
+  /// </param>
   /// <returns>The current <see cref="IMuninNodeBuilder"/> so that additional calls can be chained.</returns>
   public static IMuninNodeBuilder AddNode(
     this IMuninServiceBuilder builder
@@ -25,7 +27,7 @@ this IMuninServiceBuilder builder
   /// Adds a <c>Munin-Node</c> to the <see cref="IMuninServiceBuilder"/> with specified configurations.
   /// </summary>
   /// <param name="builder">
-  /// An <see cref="IMuninNodeBuilder"/> to build the <c>Munin-Node</c> to be added.
+  /// An <see cref="IMuninServiceBuilder"/> that the built <c>Munin-Node</c> will be added to.
   /// </param>
   /// <param name="configure">
   /// An <see cref="Action{MuninNodeOptions}"/> to setup <see cref="MuninNodeOptions"/> to
@@ -36,29 +38,48 @@ public static IMuninNodeBuilder AddNode(
     this IMuninServiceBuilder builder,
     Action<MuninNodeOptions> configure
   )
+    => AddNode<MuninNodeOptions>(
+      builder: builder ?? throw new ArgumentNullException(nameof(builder)),
+      configure: configure ?? throw new ArgumentNullException(nameof(configure))
+    );
+
+  /// <summary>
+  /// Adds a <c>Munin-Node</c> to the <see cref="IMuninServiceBuilder"/> with specified configurations.
+  /// </summary>
+  /// <typeparam name="TMuninNodeOptions">
+  /// The extended type of <see cref="MuninNodeOptions"/> to configure the <c>Munin-Node</c>.
+  /// </typeparam>
+  /// <param name="builder">
+  /// An <see cref="IMuninServiceBuilder"/> that the built <c>Munin-Node</c> will be added to.
+  /// </param>
+  /// <param name="configure">
+  /// An <see cref="Action{TMuninNodeOptions}"/> to setup <typeparamref name="TMuninNodeOptions"/> to
+  /// configure the <c>Munin-Node</c> to be built.
+  /// </param>
+  /// <returns>The current <see cref="IMuninNodeBuilder"/> so that additional calls can be chained.</returns>
+  public static IMuninNodeBuilder AddNode<TMuninNodeOptions>(
+    this IMuninServiceBuilder builder,
+    Action<TMuninNodeOptions> configure
+  )
+    where TMuninNodeOptions : MuninNodeOptions, new()
   {
     if (builder is null)
       throw new ArgumentNullException(nameof(builder));
     if (configure is null)
       throw new ArgumentNullException(nameof(configure));
 
-    var options = new MuninNodeOptions();
+    var configuredOptions = new TMuninNodeOptions();
 
-    configure(options);
+    configure(configuredOptions);
 
     var nodeBuilder = new MuninNodeBuilder(
       serviceBuilder: builder,
-      serviceKey: options.HostName // use configured hostname as a service key and option name
+      serviceKey: configuredOptions.HostName // use configured hostname as a service key and option name
     );
 
-    _ = builder.Services.Configure<MuninNodeOptions>(
+    _ = builder.Services.Configure<TMuninNodeOptions>(
       name: nodeBuilder.ServiceKey, // configure MuninNodeOptions for this builder
-      opts => {
-        opts.Address = options.Address;
-        opts.Port = options.Port;
-        opts.HostName = options.HostName;
-        opts.AccessRule = options.AccessRule;
-      }
+      options => options.Configure(configuredOptions)
     );
 
     builder.Services.Add(

src/Smdn.Net.MuninNode/Smdn.Net.MuninNode.DependencyInjection/MuninNodeBuilder.cs

@@ -73,7 +73,7 @@ public IMuninNode Build(IServiceProvider serviceProvider)
       throw new ArgumentNullException(nameof(serviceProvider));
 
     return new DefaultMuninNode(
-      options: serviceProvider.GetRequiredService<IOptionsMonitor<MuninNodeOptions>>().Get(name: ServiceKey),
+      options: GetConfiguredOptions<MuninNodeOptions>(serviceProvider),
       pluginProvider: buildPluginProvider is null
         ? new PluginProvider(
             plugins: pluginFactories.Select(factory => factory(serviceProvider)).ToList(),
@@ -98,4 +98,15 @@ public PluginProvider(
       SessionCallback = sessionCallback;
     }
   }
+
+  protected TMuninNodeOptions GetConfiguredOptions<TMuninNodeOptions>(IServiceProvider serviceProvider)
+    where TMuninNodeOptions : MuninNodeOptions
+  {
+    if (serviceProvider is null)
+      throw new ArgumentNullException(nameof(serviceProvider));
+
+    return serviceProvider
+      .GetRequiredService<IOptionsMonitor<TMuninNodeOptions>>()
+      .Get(name: ServiceKey);
+  }
 }

src/Smdn.Net.MuninNode/Smdn.Net.MuninNode/MuninNodeOptions.cs

@@ -14,7 +14,7 @@ namespace Smdn.Net.MuninNode;
 /// Options to configure the <c>Munin-Node</c>.
 /// </summary>
 /// <see cref="DependencyInjection.IMuninServiceBuilderExtensions.AddNode(DependencyInjection.IMuninServiceBuilder, Action{MuninNodeOptions})"/>
-public sealed class MuninNodeOptions {
+public class MuninNodeOptions {
   private static IPAddress LoopbackAddress => Socket.OSSupportsIPv6 ? IPAddress.IPv6Loopback : IPAddress.Loopback;
   private static IPAddress AnyAddress => Socket.OSSupportsIPv6 ? IPAddress.IPv6Any : IPAddress.Any;
 
@@ -124,6 +124,17 @@ public MuninNodeOptions Clone()
     => (MuninNodeOptions)MemberwiseClone();
 #endif
 
+  protected internal virtual void Configure(MuninNodeOptions baseOptions)
+  {
+    if (baseOptions is null)
+      throw new ArgumentNullException(nameof(baseOptions));
+
+    Address = baseOptions.Address;
+    Port = baseOptions.Port;
+    HostName = baseOptions.HostName;
+    AccessRule = baseOptions.AccessRule;
+  }
+
   /// <summary>
   /// Set the value of the <see cref="Address"/> property to use the address of
   /// <see cref="IPAddress.Any"/> or <see cref="IPAddress.IPv6Any"/>.

tests/Smdn.Net.MuninNode/Smdn.Net.MuninNode.DependencyInjection/IMuninServiceBuilderExtensions.cs

@@ -4,6 +4,7 @@
 using System.Linq;
 
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Options;
 
 using NUnit.Framework;
 
@@ -161,4 +162,43 @@ public void AddNode_Multiple_GetKeyedService(string hostName)
     Assert.That(node.HostName, Is.EqualTo(hostName));
     Assert.That(node, Is.Not.SameAs(anotherNode));
   }
+
+  private class CustomMuninNodeOptions : MuninNodeOptions {
+    public string? ExtraOption { get; set; }
+
+    protected override void Configure(MuninNodeOptions baseOptions)
+    {
+      base.Configure(baseOptions ?? throw new ArgumentNullException(nameof(baseOptions)));
+
+      if (baseOptions is CustomMuninNodeOptions options)
+        ExtraOption = options.ExtraOption;
+    }
+  }
+
+  [Test]
+  public void AddNode_CustomOptionsType()
+  {
+    const string HostName = "munin-node.localhost";
+    const string ExtraOptionValue = "foo";
+
+    var services = new ServiceCollection();
+
+    services.AddMunin(configure: builder => {
+      builder.AddNode<CustomMuninNodeOptions>(
+        configure: options => {
+          options.HostName = HostName;
+          options.ExtraOption = ExtraOptionValue;
+        }
+      );
+    });
+
+    var serviceProvider = services.BuildServiceProvider();
+
+    var options = serviceProvider
+      .GetRequiredService<IOptionsMonitor<CustomMuninNodeOptions>>()
+      .Get(name: HostName);
+
+    Assert.That(options.HostName, Is.EqualTo(HostName));
+    Assert.That(options.ExtraOption, Is.EqualTo(ExtraOptionValue));
+  }
 }