Merge pull request #1375 from DuendeSoftware/joe/signing-algorithms-c…

…onfig

Fix KeyManagementOptions binding

src/IdentityServer/Configuration/DependencyInjection/Options/KeyManagementOptions.cs

@@ -5,6 +5,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Linq;
 using static Duende.IdentityServer.IdentityServerConstants;
@@ -31,7 +32,7 @@ public class KeyManagementOptions
     /// If none are specified, then "RS256" will be used as the default.
     /// The first in the collection will be used as the default. 
     /// </summary>
-    public IEnumerable<SigningAlgorithmOptions> SigningAlgorithms { get; set; } = Enumerable.Empty<SigningAlgorithmOptions>();
+    public ICollection<SigningAlgorithmOptions> SigningAlgorithms { get; set; } = new List<SigningAlgorithmOptions>();
 
     internal string DefaultSigningAlgorithm => SigningAlgorithms.First().Name;
     internal IEnumerable<string> AllowedSigningAlgorithmNames => SigningAlgorithms.Select(x => x.Name);
@@ -160,9 +161,18 @@ internal void Validate()
 /// </summary>
 public class SigningAlgorithmOptions
 {
+    /// <summary>
+    /// Parameterless constructor, required for binding
+    /// </summary>
+    public SigningAlgorithmOptions()
+    {
+
+    }
+
     /// <summary>
     /// Constructor.
     /// </summary>
+    [SetsRequiredMembers]
     public SigningAlgorithmOptions(string name)
     {
         Name = name ?? throw new ArgumentNullException(nameof(name));
@@ -171,7 +181,7 @@ public SigningAlgorithmOptions(string name)
     /// <summary>
     /// The algorithm name.
     /// </summary>
-    public string Name { get; set; }
+    public required string Name { get; set; }
 
     /// <summary>
     /// Indicates if an X.509 certificate is to be used to contain the key. Defaults to false.