Added MicrosoftOAuth2HttpServiceClient adapter for SSO

src/ApiHost1/appsettings.Azure.json

@@ -24,6 +24,12 @@
         "DbCredentials": "",
         "DbName": "SaaStack"
       }
+    },
+    "MicrosoftIdentity": {
+      "ClientId": "",
+      "ClientSecret": "",
+      "BaseUrl": "https://localhost:5656/microsoftidentity",
+      "RedirectUri": "https://localhost:5001/sso/microsoft"
     }
   }
 }

src/IdentityInfrastructure/ApplicationServices/MicrosoftSSOAuthenticationProvider.cs

@@ -0,0 +1,128 @@
+using System.IdentityModel.Tokens.Jwt;
+using System.Security.Claims;
+using System.Text.Json;
+using Application.Interfaces;
+using Application.Resources.Shared;
+using Application.Services.Shared;
+using Common;
+using Common.Configuration;
+using Common.Extensions;
+using IdentityApplication.ApplicationServices;
+using Infrastructure.Interfaces;
+using Infrastructure.Shared.ApplicationServices.External;
+
+namespace IdentityInfrastructure.ApplicationServices;
+
+/// <summary>
+///     Provides a <see cref="ISSOAuthenticationProvider" /> for handling Microsoft Identity SSO
+/// </summary>
+public class MicrosoftSSOAuthenticationProvider : ISSOAuthenticationProvider
+{
+    public const string SSOName = "microsoft";
+    private const string ServiceName = "MicrosoftIdentityService";
+    private readonly IOAuth2Service _auth2Service;
+
+    public MicrosoftSSOAuthenticationProvider(IRecorder recorder, IHttpClientFactory clientFactory,
+        JsonSerializerOptions jsonOptions, IConfigurationSettings settings) : this(
+        new MicrosoftOAuth2HttpServiceClient(recorder, clientFactory, jsonOptions, settings))
+    {
+    }
+
+    private MicrosoftSSOAuthenticationProvider(IOAuth2Service auth2Service)
+    {
+        _auth2Service = auth2Service;
+    }
+
+    public async Task<Result<SSOUserInfo, Error>> AuthenticateAsync(ICallerContext caller, string authCode,
+        string? emailAddress, CancellationToken cancellationToken)
+    {
+        authCode.ThrowIfNotValuedParameter(nameof(authCode),
+            Resources.AnySSOAuthenticationProvider_MissingRefreshToken);
+
+        var retrievedTokens =
+            await _auth2Service.ExchangeCodeForTokensAsync(caller,
+                new OAuth2CodeTokenExchangeOptions(ServiceName, authCode), cancellationToken);
+        if (retrievedTokens.IsFailure)
+        {
+            return Error.NotAuthenticated();
+        }
+
+        var tokens = retrievedTokens.Value;
+        return tokens.ToSSoUserInfo();
+    }
+
+    public string ProviderName => SSOName;
+
+    public async Task<Result<ProviderAuthenticationTokens, Error>> RefreshTokenAsync(ICallerContext caller,
+        string refreshToken, CancellationToken cancellationToken)
+    {
+        refreshToken.ThrowIfNotValuedParameter(nameof(refreshToken),
+            Resources.AnySSOAuthenticationProvider_MissingRefreshToken);
+
+        var retrievedTokens =
+            await _auth2Service.RefreshTokenAsync(caller,
+                new OAuth2RefreshTokenOptions(ServiceName, refreshToken),
+                cancellationToken);
+        if (retrievedTokens.IsFailure)
+        {
+            return Error.NotAuthenticated();
+        }
+
+        var tokens = retrievedTokens.Value;
+
+        var accessToken = tokens.Single(tok => tok.Type == TokenType.AccessToken);
+        var refreshedToken = tokens.FirstOrDefault(tok => tok.Type == TokenType.RefreshToken);
+        var idToken = tokens.FirstOrDefault(tok => tok.Type == TokenType.OtherToken);
+        return new ProviderAuthenticationTokens
+        {
+            Provider = SSOName,
+            AccessToken = new AuthenticationToken
+            {
+                ExpiresOn = accessToken.ExpiresOn,
+                Type = TokenType.AccessToken,
+                Value = accessToken.Value
+            },
+            RefreshToken = refreshedToken.Exists()
+                ? new AuthenticationToken
+                {
+                    ExpiresOn = refreshedToken.ExpiresOn,
+                    Type = TokenType.RefreshToken,
+                    Value = refreshedToken.Value
+                }
+                : null,
+            OtherTokens = idToken.Exists()
+                ?
+                [
+                    new AuthenticationToken
+                    {
+                        ExpiresOn = idToken.ExpiresOn,
+                        Type = TokenType.OtherToken,
+                        Value = idToken.Value
+                    }
+                ]
+                : []
+        };
+    }
+}
+
+internal static class MicrosoftSSOAuthenticationProviderExtensions
+{
+    public static Result<SSOUserInfo, Error> ToSSoUserInfo(this List<AuthToken> tokens)
+    {
+        var idToken = tokens.FirstOrDefault(t => t.Type == TokenType.OtherToken);
+        if (idToken.NotExists())
+        {
+            return Error.NotAuthenticated();
+        }
+
+        var claims = new JwtSecurityTokenHandler().ReadJwtToken(idToken.Value).Claims.ToArray();
+        var emailAddress = claims.Single(c => c.Type == ClaimTypes.Email).Value;
+        var firstName = claims.Single(c => c.Type == ClaimTypes.GivenName).Value;
+        var lastName = claims.Single(c => c.Type == "family_name").Value;
+        var timezone =
+            Timezones.FindOrDefault(claims.Single(c => c.Type == AuthenticationConstants.Claims.ForTimezone).Value);
+        var country = CountryCodes.FindOrDefault(claims.Single(c => c.Type == ClaimTypes.Country).Value);
+
+        return new SSOUserInfo(tokens, emailAddress, firstName, lastName, timezone, country);
+    }
+}

src/Infrastructure.Shared.UnitTests/ApplicationServices/External/MicrosoftOAuth2HttpServiceClientSpec.cs

@@ -0,0 +1,62 @@
+using Application.Interfaces;
+using Application.Resources.Shared;
+using Application.Services.Shared;
+using FluentAssertions;
+using Infrastructure.Shared.ApplicationServices.External;
+using Moq;
+using UnitTesting.Common;
+using Xunit;
+
+namespace Infrastructure.Shared.UnitTests.ApplicationServices.External;
+
+[Trait("Category", "Unit")]
+public class MicrosoftOAuth2HttpServiceClientSpec
+{
+    private readonly Mock<ICallerContext> _caller;
+    private readonly Mock<IOAuth2Service> _oauth2Service;
+    private readonly MicrosoftOAuth2HttpServiceClient _serviceClient;
+
+    public MicrosoftOAuth2HttpServiceClientSpec()
+    {
+        _caller = new Mock<ICallerContext>();
+        _oauth2Service = new Mock<IOAuth2Service>();
+
+        _serviceClient = new MicrosoftOAuth2HttpServiceClient(_oauth2Service.Object);
+    }
+
+    [Fact]
+    public async Task WhenExchangeCodeForTokensAsync_ThenDelegates()
+    {
+        var tokens = new List<AuthToken>();
+        _oauth2Service.Setup(oas => oas.ExchangeCodeForTokensAsync(It.IsAny<ICallerContext>(),
+                It.IsAny<OAuth2CodeTokenExchangeOptions>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(tokens);
+        var options = new OAuth2CodeTokenExchangeOptions("aservicename", "acode");
+
+        var result = await _serviceClient.ExchangeCodeForTokensAsync(_caller.Object,
+            options, CancellationToken.None);
+
+        result.Should().BeSuccess();
+        result.Value.Should().BeSameAs(tokens);
+        _oauth2Service.Verify(oas => oas.ExchangeCodeForTokensAsync(_caller.Object,
+            options, It.IsAny<CancellationToken>()));
+    }
+
+    [Fact]
+    public async Task WhenRefreshTokenAsync_ThenDelegates()
+    {
+        var tokens = new List<AuthToken>();
+        _oauth2Service.Setup(oas => oas.RefreshTokenAsync(It.IsAny<ICallerContext>(),
+                It.IsAny<OAuth2RefreshTokenOptions>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(tokens);
+        var options = new OAuth2RefreshTokenOptions("aservicename", "arefreshtoken");
+
+        var result = await _serviceClient.RefreshTokenAsync(_caller.Object,
+            options, CancellationToken.None);
+
+        result.Should().BeSuccess();
+        result.Value.Should().BeSameAs(tokens);
+        _oauth2Service.Verify(oas => oas.RefreshTokenAsync(_caller.Object,
+            options, It.IsAny<CancellationToken>()));
+    }
+}

src/Infrastructure.Shared/ApplicationServices/External/MicrosoftOAuth2HttpServiceClient.cs

@@ -0,0 +1,49 @@
+using System.Text.Json;
+using Application.Interfaces;
+using Application.Resources.Shared;
+using Application.Services.Shared;
+using Common;
+using Common.Configuration;
+using Infrastructure.Web.Common.Clients;
+
+namespace Infrastructure.Shared.ApplicationServices.External;
+
+/// <summary>
+///     Provides a <see cref="IOAuth2Service" /> for accessing Microsoft Identity platform
+///     <see
+///         href="https://learn.microsoft.com/en-us/entra/identity-platform/v2-oauth2-auth-code-flow#redeem-a-code-for-an-access-token" />
+/// </summary>
+public class MicrosoftOAuth2HttpServiceClient : IOAuth2Service
+{
+    private const string BaseUrlSettingName = "ApplicationServices:MicrosoftIdentity:BaseUrl";
+    private const string ClientIdSettingName = "ApplicationServices:MicrosoftIdentity:ClientId";
+    private const string ClientSecretSettingName = "ApplicationServices:MicrosoftIdentity:ClientSecret";
+    private const string RedirectUriSettingName = "ApplicationServices:MicrosoftIdentity:RedirectUri";
+    private readonly IOAuth2Service _oauth2Service;
+
+    public MicrosoftOAuth2HttpServiceClient(IRecorder recorder, IHttpClientFactory clientFactory,
+        JsonSerializerOptions jsonOptions, IConfigurationSettings settings) : this(new GenericOAuth2HttpServiceClient(
+        recorder,
+        new ApiServiceClient(clientFactory, jsonOptions, settings.GetString(BaseUrlSettingName)),
+        settings.GetString(ClientIdSettingName), settings.GetString(ClientSecretSettingName),
+        settings.GetString(RedirectUriSettingName)))
+    {
+    }
+
+    internal MicrosoftOAuth2HttpServiceClient(IOAuth2Service oauth2Service)
+    {
+        _oauth2Service = oauth2Service;
+    }
+
+    public async Task<Result<List<AuthToken>, Error>> ExchangeCodeForTokensAsync(ICallerContext caller,
+        OAuth2CodeTokenExchangeOptions options, CancellationToken cancellationToken)
+    {
+        return await _oauth2Service.ExchangeCodeForTokensAsync(caller, options, cancellationToken);
+    }
+
+    public async Task<Result<List<AuthToken>, Error>> RefreshTokenAsync(ICallerContext caller,
+        OAuth2RefreshTokenOptions options, CancellationToken cancellationToken)
+    {
+        return await _oauth2Service.RefreshTokenAsync(caller, options, cancellationToken);
+    }
+}