#563 Allow to use multiple authentication methods (#575)

Modules/Authentication/GenHTTP.Modules.Authentication.csproj

@@ -14,7 +14,7 @@
         <Version>9.3.0</Version>
 
         <Authors>Andreas Nägeli</Authors>
-        <Company/>
+        <Company />
 
         <PackageLicenseFile>LICENSE</PackageLicenseFile>
         <PackageProjectUrl>https://genhttp.org/</PackageProjectUrl>
@@ -35,20 +35,20 @@
 
     <ItemGroup>
 
-        <None Include="..\..\LICENSE" Pack="true" PackagePath="\"/>
-        <None Include="..\..\Resources\icon.png" Pack="true" PackagePath="\"/>
+        <None Include="..\..\LICENSE" Pack="true" PackagePath="\" />
+        <None Include="..\..\Resources\icon.png" Pack="true" PackagePath="\" />
 
     </ItemGroup>
 
     <ItemGroup>
 
-        <ProjectReference Include="..\..\API\GenHTTP.Api.csproj"/>
+        <ProjectReference Include="..\..\API\GenHTTP.Api.csproj" />
 
         <ProjectReference Include="..\Reflection\GenHTTP.Modules.Reflection.csproj" />
 
         <PackageReference Include="Microsoft.IdentityModel.Protocols.OpenIdConnect" Version="8.2.1" />
 
-        <PackageReference Include="Microsoft.SourceLink.GitHub" Version="8.0.0" PrivateAssets="All"/>
+        <PackageReference Include="Microsoft.SourceLink.GitHub" Version="8.0.0" PrivateAssets="All" />
 
         <PackageReference Include="System.IdentityModel.Tokens.Jwt" Version="8.2.1" />
 

Modules/Authentication/Multi/MultiAuthenticationConcern.cs

@@ -0,0 +1,83 @@
+using GenHTTP.Api.Content;
+using GenHTTP.Api.Protocol;
+
+namespace GenHTTP.Modules.Authentication.Multi;
+
+public sealed class MultiAuthenticationConcern : IConcern
+{
+    #region Get-/Setters
+
+    public IHandler Content { get; }
+
+    private readonly IConcern[] _delegatingConcerns;
+
+    #endregion
+
+    #region Initialization
+
+    public MultiAuthenticationConcern(IHandler content, IConcern[] delegatingConcerns)
+    {
+        Content = content;
+        _delegatingConcerns = delegatingConcerns;
+    }
+
+    #endregion
+
+    #region Functionality
+
+    public async ValueTask<IResponse?> HandleAsync(IRequest request)
+    {
+        ResponseOrException? lastResponse = null;
+        foreach (var concern in _delegatingConcerns)
+        {
+            lastResponse?.Dispose();
+
+            try
+            {
+                lastResponse = new(await concern.HandleAsync(request));
+            }
+            catch (ProviderException e)
+            {
+                lastResponse = new(Exception: e);
+            }
+
+            if (lastResponse.Status != ResponseStatus.Unauthorized)
+            {
+                return lastResponse.Get();
+            }
+        }
+
+        return lastResponse?.Get() ??
+                     request.Respond()
+                            .Status(ResponseStatus.Unauthorized)
+                            .Build();
+    }
+
+    public ValueTask PrepareAsync() => Content.PrepareAsync();
+
+    #endregion
+
+    #region Helper structure
+
+    private sealed record ResponseOrException(IResponse? Response = null, ProviderException? Exception = null) : IDisposable
+    { 
+        public IResponse? Get()
+        {
+            if (Exception != null)
+            {
+                throw Exception;
+            }
+
+            return Response;
+        }
+
+        public void Dispose()
+        {
+            Response?.Dispose();
+        }
+
+        public ResponseStatus? Status => Exception?.Status ?? Response?.Status.KnownStatus;
+    }
+
+    #endregion
+}

Modules/Authentication/Multi/MultiAuthenticationConcernBuilder.cs

@@ -0,0 +1,88 @@
+using GenHTTP.Api.Content;
+using GenHTTP.Api.Infrastructure;
+using GenHTTP.Modules.Authentication.ApiKey;
+using GenHTTP.Modules.Authentication.Basic;
+using GenHTTP.Modules.Authentication.Bearer;
+using GenHTTP.Modules.Authentication.ClientCertificate;
+
+namespace GenHTTP.Modules.Authentication.Multi;
+
+/// <summary>
+/// Builder for creating a multi-concern authentication handler.
+/// </summary>
+public sealed class MultiAuthenticationConcernBuilder : IConcernBuilder
+{
+    #region Fields
+
+    private readonly List<IConcernBuilder> _delegatingConcernsBuilders = [];
+
+    #endregion
+
+    #region Private add functionality
+
+    private MultiAuthenticationConcernBuilder AddIfNotNull(IConcernBuilder concernBuilder)
+    {
+        if (concernBuilder == null) return this;
+
+        _delegatingConcernsBuilders.Add(concernBuilder);
+        return this;
+    }
+
+    #endregion
+
+    #region Functionality
+
+    /// <summary>
+    /// Add nested API concern builder to this multi concern.
+    /// </summary>
+    /// <param name="apiKeyBuilder">Nested API key concern builder</param>
+    public MultiAuthenticationConcernBuilder Add(ApiKeyConcernBuilder apiKeyBuilder)
+        => AddIfNotNull(apiKeyBuilder);
+
+    /// <summary>
+    /// Add nested API concern builder to this multi concern.
+    /// </summary>
+    /// <param name="basicBuilder">Nested Basic concern builder</param>
+    public MultiAuthenticationConcernBuilder Add(BasicAuthenticationConcernBuilder basicBuilder)
+        => AddIfNotNull(basicBuilder);
+
+    /// <summary>
+    /// Add nested API concern builder to this multi concern.
+    /// </summary>
+    /// <param name="basicKnownUsersBuilder">Nested Basic Known Users concern builder</param>
+    public MultiAuthenticationConcernBuilder Add(BasicAuthenticationKnownUsersBuilder basicKnownUsersBuilder)
+        => AddIfNotNull(basicKnownUsersBuilder);
+
+    /// <summary>
+    /// Add nested API concern builder to this multi concern.
+    /// </summary>
+    /// <param name="bearerBuilder">Nested Bearer concern builder</param>
+    public MultiAuthenticationConcernBuilder Add(BearerAuthenticationConcernBuilder bearerBuilder)
+        => AddIfNotNull(bearerBuilder);
+
+    /// <summary>
+    /// Add nested API concern builder to this multi concern.
+    /// </summary>
+    /// <param name="clientCertificateBuilder">Nested Client Certificate concern builder</param>
+    public MultiAuthenticationConcernBuilder Add(ClientCertificateAuthenticationBuilder clientCertificateBuilder)
+        => AddIfNotNull(clientCertificateBuilder);
+
+    /// <summary>
+    /// Construct the multi concern.
+    /// </summary>
+    /// <param name="content"></param>
+    /// <returns></returns>
+    public IConcern Build(IHandler content)
+    {
+        var delegatingConcerns = _delegatingConcernsBuilders.Select(x => x.Build(content)).ToArray();
+        if (delegatingConcerns.Length == 0) throw new BuilderMissingPropertyException("Concerns");
+
+        return new MultiAuthenticationConcern(
+            content,
+            delegatingConcerns
+            );
+    }
+
+    #endregion
+
+}

Modules/Authentication/MultiAuthentication.cs

@@ -0,0 +1,16 @@
+using GenHTTP.Modules.Authentication.Multi;
+
+namespace GenHTTP.Modules.Authentication;
+
+public static class MultiAuthentication
+{
+    #region Builder
+
+    /// <summary>
+    /// Creates a authentication handler that will use
+    /// underlying handlers to authenticate the request.
+    /// </summary>
+    public static MultiAuthenticationConcernBuilder Create() => new();
+
+    #endregion
+}