feat(api,core,infra): refactor endpoint routing and add institution account discovery

- Move login and refresh endpoints under a unified /auth route group
- Relocate institution connection logic from /accounts to /institutions
- Implement GET /institutions/{id}/available to fetch real-time Plaid
accounts
- Introduce HttpRequestBuilder utility to streamline integration testing
- Enhance PlaidService with GetAccountsAsync to support account fetching
- Clean up global usings and project structure for better domain
isolation

src/FiscalOS.API/Accounts/AccountsExtensions.cs

@@ -10,7 +10,6 @@ internal static class AccountsExtensions
       .RequireAuthorization();
 
     accountsGroup.MapAddEndpoint();
-    accountsGroup.MapConnectEndpoint();
 
     return accountsGroup;
   }

src/FiscalOS.API/Accounts/Add/Endpoint.cs

@@ -1,5 +1,3 @@
-using FiscalOS.Core.Accounts;
-
 namespace FiscalOS.API.Accounts.Add;
 
 internal static class Endpoint

src/FiscalOS.API/Accounts/Add/Request.cs

@@ -1,4 +1,3 @@
-
 namespace FiscalOS.API.Accounts.Add;
 
 public record Request : IValidatableObject

src/FiscalOS.API/Auth/AuthExtensions.cs

@@ -0,0 +1,18 @@
+namespace FiscalOS.API.Auth;
+
+internal static class AuthExtensions
+{
+  private const string RouteGroupPrefix = "/auth";
+
+  public static RouteGroupBuilder MapAuthEndpoints(this WebApplication app)
+  {
+    var authGroup = app.MapGroup(RouteGroupPrefix);
+
+    authGroup.MapLoginEndpoint();
+
+    authGroup.MapRefreshEndpoint()
+      .RequireAuthorization(Schemes.AllowExpiredTokens);
+
+    return authGroup;
+  }
+}

src/FiscalOS.API/Auth/Login/Endpoint.cs

@@ -1,12 +1,12 @@
-namespace FiscalOS.API.Login;
+namespace FiscalOS.API.Auth.Login;
 
 internal static class Endpoint
 {
   private const string Route = "/login";
 
-  public static RouteHandlerBuilder MapLoginEndpoint(this WebApplication app)
+  public static RouteHandlerBuilder MapLoginEndpoint(this RouteGroupBuilder groupBuilder)
   {
-    return app.MapPost(Route, HandleAsync);
+    return groupBuilder.MapPost(Route, HandleAsync);
   }
 
   private static async Task<IResult> HandleAsync(

src/FiscalOS.API/Auth/Login/Request.cs

@@ -1,4 +1,4 @@
-namespace FiscalOS.API.Login;
+namespace FiscalOS.API.Auth.Login;
 
 public record Request : IValidatableObject
 {

src/FiscalOS.API/Auth/Login/Response.cs

@@ -1,4 +1,4 @@
-namespace FiscalOS.API.Login;
+namespace FiscalOS.API.Auth.Login;
 
 internal sealed record Response
 {

src/FiscalOS.API/Auth/Refresh/Endpoint.cs

@@ -1,12 +1,12 @@
-namespace FiscalOS.API.Refresh;
+namespace FiscalOS.API.Auth.Refresh;
 
 internal static class Endpoint
 {
   private const string Route = "/refresh";
 
-  public static RouteHandlerBuilder MapRefreshEndpoint(this WebApplication app)
+  public static RouteHandlerBuilder MapRefreshEndpoint(this RouteGroupBuilder groupBuilder)
   {
-    return app.MapPost(Route, HandleAsync);
+    return groupBuilder.MapPost(Route, HandleAsync);
   }
 
   private static async Task<IResult> HandleAsync(

src/FiscalOS.API/Auth/Refresh/Response.cs

@@ -1,4 +1,4 @@
-namespace FiscalOS.API.Refresh;
+namespace FiscalOS.API.Auth.Refresh;
 
 internal sealed record Response
 {

src/FiscalOS.API/Http/HttpContextExtensions.cs

@@ -1,5 +1,3 @@
-using FiscalOS.Core.Identity;
-
 namespace FiscalOS.API.Http;
 
 internal static class HttpContextExtensions

src/FiscalOS.API/Institutions/Connect/Endpoint.cs

@@ -1,6 +1,4 @@
-using FiscalOS.Core.Accounts;
-
-namespace FiscalOS.API.Accounts.Connect;
+namespace FiscalOS.API.Institutions.Connect;
 
 internal static class Endpoint
 {

src/FiscalOS.API/Institutions/Connect/Request.cs

@@ -1,4 +1,4 @@
-namespace FiscalOS.API.Accounts.Connect;
+namespace FiscalOS.API.Institutions.Connect;
 
 public record Request : IValidatableObject
 {

src/FiscalOS.API/Institutions/GetAvailable/Endpoint.cs

@@ -0,0 +1,50 @@
+namespace FiscalOS.API.Institutions.GetAvailable;
+
+internal static class Endpoint
+{
+  private const string Route = "/{id}/available";
+
+  public static RouteHandlerBuilder MapGetAvailableEndpoint(this RouteGroupBuilder groupBuilder)
+  {
+    return groupBuilder.MapGet(Route, HandleAsync);
+  }
+
+  private static async Task<IResult> HandleAsync(
+    HttpContext httpContext,
+    [FromRoute] Guid id,
+    [FromServices] AppDbContext appDbContext,
+    [FromServices] PlaidService plaidService,
+    [FromServices] IEncryptor encryptor,
+    CancellationToken ct
+  )
+  {
+    var userId = httpContext.GetUserId();
+
+    var user = await appDbContext.Users
+      .Include(u => u.Institutions.Where(i => i.Id == id))
+      .ThenInclude(i => i.Metadata)
+      .SingleOrDefaultAsync(u => u.Id == userId, ct);
+
+    if (user is null)
+    {
+      return Results.Unauthorized();
+    }
+
+    if (user.Institutions.Any() is false)
+    {
+      return Results.NotFound();
+    }
+
+    var institution = user.Institutions.First();
+
+    if (institution.Metadata is not PlaidMetadata plaidMetadata)
+    {
+      return Results.BadRequest();
+    }
+
+    var accessToken = await encryptor.DecryptAsyncFor(user, plaidMetadata.EncryptedAccessToken, ct);
+    var accounts = await plaidService.GetAccountsAsync(accessToken);
+
+    return Results.Ok(accounts);
+  }
+}

src/FiscalOS.API/Institutions/InstitutionsExtensions.cs

@@ -0,0 +1,17 @@
+namespace FiscalOS.API.Institutions;
+
+internal static class InstitutionsExtensions
+{
+  private const string RouteGroupPrefix = "/institutions";
+
+  public static RouteGroupBuilder MapInstitutionsEndpoints(this WebApplication app)
+  {
+    var institutionsGroup = app.MapGroup(RouteGroupPrefix)
+      .RequireAuthorization();
+
+    institutionsGroup.MapConnectEndpoint();
+    institutionsGroup.MapGetAvailableEndpoint();
+
+    return institutionsGroup;
+  }
+}

src/FiscalOS.API/Program.cs

@@ -32,11 +32,8 @@ app.UseAuthentication();
 app.UseAuthorization();
 app.UseStatusCodePages();
 
-app.MapLoginEndpoint();
-
-app.MapRefreshEndpoint()
-  .RequireAuthorization(Schemes.AllowExpiredTokens);
-
+app.MapAuthEndpoints();
 app.MapAccountsEndpoints();
+app.MapInstitutionsEndpoints();
 
 app.Run();

src/FiscalOS.API/Usings.cs

@@ -2,12 +2,17 @@ global using System.ComponentModel.DataAnnotations;
 global using System.Security.Claims;
 global using System.Text.Json.Serialization;
 
+global using FiscalOS.Core.Identity;
 global using FiscalOS.API.Accounts;
 global using FiscalOS.API.Accounts.Add;
-global using FiscalOS.API.Accounts.Connect;
+global using FiscalOS.API.Auth;
+global using FiscalOS.API.Auth.Login;
+global using FiscalOS.API.Auth.Refresh;
 global using FiscalOS.API.Http;
-global using FiscalOS.API.Login;
-global using FiscalOS.API.Refresh;
+global using FiscalOS.API.Institutions;
+global using FiscalOS.API.Institutions.Connect;
+global using FiscalOS.API.Institutions.GetAvailable;
+global using FiscalOS.Core.Accounts;
 global using FiscalOS.Core.Authentication;
 global using FiscalOS.Core.Security;
 global using FiscalOS.Infra.Accounts.Plaid;

src/FiscalOS.Infra/Accounts/Plaid/PlaidService.cs

@@ -1,3 +1,4 @@
+
 namespace FiscalOS.Infra.Accounts.Plaid;
 
 public sealed class PlaidService
@@ -30,6 +31,21 @@ public sealed class PlaidService
     return (ptr.ItemId, ptr.AccessToken);
   }
 
+  public async Task<List<Going.Plaid.Entity.Account>> GetAccountsAsync(string accessToken)
+  {
+    var ar = await _client.AccountsGetAsync(new()
+    {
+      AccessToken = accessToken,
+    }).ConfigureAwait(false);
+
+    if (ar.IsSuccessStatusCode is false)
+    {
+      throw new PlaidException("Unable to retrieve accounts");
+    }
+
+    return [.. ar.Accounts];
+  }
+
   public async Task<ItemWithConsentFields> GetItemAsync(string accessToken)
   {
     var ar = await _client.ItemGetAsync(new()

tests/FiscalOS.API.Tests/Assertions/HttpResponseMessageAssertions.cs

@@ -21,12 +21,6 @@ internal sealed class HttpResponseMessageAssertions(
     HttpStatusCode expectedStatusCode
   )
   {
-    _chain.ForCondition(Subject.Content.Headers.ContentType?.MediaType is "application/json")
-      .FailWith(
-        "Expected response to be application/json, but found {0}",
-        Subject.Content.Headers.ContentType?.MediaType
-      );
-
     _chain.ForCondition(Subject.StatusCode == expectedStatusCode)
       .FailWith(
         "Expected response status code to be {0}, but found {1}",
@@ -34,6 +28,13 @@ internal sealed class HttpResponseMessageAssertions(
         Subject.StatusCode
       );
 
+    _chain.ForCondition(Subject.Content.Headers.ContentType?.MediaType is "application/json")
+      .FailWith(
+        "Expected response to be application/json, but found {0}",
+        Subject.Content.Headers.ContentType?.MediaType
+      );
+
+
     var content = await Subject.Content.ReadFromJsonAsync<T>();
 
     _chain.ForCondition(content is not null)

tests/FiscalOS.API.Tests/Infra/HttpRequestBuilder.cs

@@ -0,0 +1,128 @@
+namespace FiscalOS.API.Tests.Infra;
+
+internal sealed class HttpRequestBuilder
+{
+  private HttpMethod _method = HttpMethod.Get;
+  private Uri? _uri;
+  private object? _body;
+  private string? _bearerToken;
+  private readonly Dictionary<string, string> _cookies = [];
+  private readonly Dictionary<string, string> _headers = [];
+
+  private HttpRequestBuilder()
+  {
+  }
+
+  public static HttpRequestBuilder New() => new();
+
+  public HttpRequestBuilder WithMethod(HttpMethod method)
+  {
+    _method = method;
+    return this;
+  }
+
+  public HttpRequestBuilder WithUri(Uri uri)
+  {
+    _uri = uri;
+    return this;
+  }
+
+  public HttpRequestBuilder WithBody<T>(T body)
+  {
+    _body = body;
+    return this;
+  }
+
+  public HttpRequestBuilder WithBearerToken(string token)
+  {
+    _bearerToken = token;
+    return this;
+  }
+
+  public HttpRequestBuilder WithUserId(Guid userId)
+  {
+    _bearerToken = JwtTokenBuilder.New()
+      .WithClaim(JwtRegisteredClaimNames.Sub, userId.ToString())
+      .Build();
+
+    return this;
+  }
+
+  public HttpRequestBuilder WithCookie(string name, string value)
+  {
+    _cookies[name] = value;
+    return this;
+  }
+
+  public HttpRequestBuilder WithRefreshCookie(string token)
+  {
+    return WithCookie("fiscalos_refresh_cookie", token);
+  }
+
+  public HttpRequestBuilder WithHeader(string name, string value)
+  {
+    _headers[name] = value;
+    return this;
+  }
+
+  public HttpRequestBuilder Post(Uri uri)
+  {
+    _method = HttpMethod.Post;
+    _uri = uri;
+    return this;
+  }
+
+  public HttpRequestBuilder Get(Uri uri)
+  {
+    _method = HttpMethod.Get;
+    _uri = uri;
+    return this;
+  }
+
+  public HttpRequestBuilder Put(Uri uri)
+  {
+    _method = HttpMethod.Put;
+    _uri = uri;
+    return this;
+  }
+
+  public HttpRequestBuilder Delete(Uri uri)
+  {
+    _method = HttpMethod.Delete;
+    _uri = uri;
+    return this;
+  }
+
+  public HttpRequestMessage Build()
+  {
+    if (_uri is null)
+    {
+      throw new InvalidOperationException("URI must be set before building the request.");
+    }
+
+    var request = new HttpRequestMessage(_method, _uri);
+
+    if (_body is not null)
+    {
+      var json = JsonSerializer.Serialize(_body);
+      request.Content = new StringContent(json, Encoding.UTF8, "application/json");
+    }
+
+    if (_bearerToken is not null)
+    {
+      request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", _bearerToken);
+    }
+
+    foreach (var (key, value) in _cookies)
+    {
+      request.Headers.Add("Cookie", $"{key}={value}");
+    }
+
+    foreach (var (key, value) in _headers)
+    {
+      request.Headers.Add(key, value);
+    }
+
+    return request;
+  }
+}

tests/FiscalOS.API.Tests/Infra/SerializableDictionary.cs

@@ -1,4 +1,4 @@
-namespace FiscalOS.API.Tests.Common;
+namespace FiscalOS.API.Tests.Infra;
 
 public interface ISerializableDictionary<TKey, TValue> : IDictionary<TKey, TValue>, IXunitSerializable
 {

tests/FiscalOS.API.Tests/Infra/TestApi.cs

@@ -1,5 +1,3 @@
-using Microsoft.Extensions.Configuration;
-
 namespace FiscalOS.API.Tests.Infra;
 
 public class TestApi : WebApplicationFactory<Program>

tests/FiscalOS.API.Tests/Integration/Accounts/AddTests.cs

@@ -1,7 +1,7 @@
 using Account = FiscalOS.Core.Accounts.Account;
 using Institution = FiscalOS.Core.Accounts.Institution;
 
-namespace FiscalOS.API.Tests.Integration;
+namespace FiscalOS.API.Tests.Integration.Accounts;
 
 public class AddTests(TestApi testApi) : IntegrationTest(testApi)
 {
@@ -18,17 +18,12 @@ public class AddTests(TestApi testApi) : IntegrationTest(testApi)
   [Fact]
   public async Task Add_WhenCalledWithoutInstitutionIdOrAccountIdOrAccountName_ItShouldReturn400WithProblemDetails()
   {
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(AddUri)
+      .WithUserId(Guid.NewGuid())
+      .WithBody(new { })
       .Build();
 
-    using var content = new StringContent(JsonSerializer.Serialize(new { }), Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, AddUri)
-    {
-      Content = content
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeValidationProblemDetails(new Dictionary<string, string[]>()
@@ -42,22 +37,16 @@ public class AddTests(TestApi testApi) : IntegrationTest(testApi)
   [Fact]
   public async Task Add_WhenCalledWithoutInstitutionId_ItShouldReturn400WithProblemDetails()
   {
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(AddUri)
+      .WithUserId(Guid.NewGuid())
+      .WithBody(new
+      {
+        plaidAccountId = "accountId",
+        plaidAccountName = "Some Account",
+      })
       .Build();
 
-    var json = JsonSerializer.Serialize(new
-    {
-      plaidAccountId = "accountId",
-      plaidAccountName = "Some Account",
-    });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, AddUri)
-    {
-      Content = content
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeValidationProblemDetails(new Dictionary<string, string[]>()
@@ -69,22 +58,16 @@ public class AddTests(TestApi testApi) : IntegrationTest(testApi)
   [Fact]
   public async Task Add_WhenCalledWithoutAccountId_ItShouldReturn400WithProblemDetails()
   {
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(AddUri)
+      .WithUserId(Guid.NewGuid())
+      .WithBody(new
+      {
+        plaidInstitutionId = "institutionId",
+        plaidAccountName = "Some Account",
+      })
       .Build();
 
-    var json = JsonSerializer.Serialize(new
-    {
-      plaidInstitutionId = "institutionId",
-      plaidAccountName = "Some Account",
-    });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, AddUri)
-    {
-      Content = content
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeValidationProblemDetails(new Dictionary<string, string[]>()
@@ -96,22 +79,16 @@ public class AddTests(TestApi testApi) : IntegrationTest(testApi)
   [Fact]
   public async Task Add_WhenCalledWithoutAccountName_ItShouldReturn400WithProblemDetails()
   {
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(AddUri)
+      .WithUserId(Guid.NewGuid())
+      .WithBody(new
+      {
+        plaidInstitutionId = "institutionId",
+        plaidAccountId = "accountId",
+      })
       .Build();
 
-    var json = JsonSerializer.Serialize(new
-    {
-      plaidInstitutionId = "institutionId",
-      plaidAccountId = "accountId",
-    });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, AddUri)
-    {
-      Content = content
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeValidationProblemDetails(new Dictionary<string, string[]>()
@@ -123,23 +100,17 @@ public class AddTests(TestApi testApi) : IntegrationTest(testApi)
   [Fact]
   public async Task Add_WhenCalledWithNonExistentUser_ItShouldReturn401WithProblemDetails()
   {
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(AddUri)
+      .WithUserId(Guid.NewGuid())
+      .WithBody(new
+      {
+        plaidInstitutionId = "id",
+        plaidAccountId = "id",
+        plaidAccountName = "Some Account",
+      })
       .Build();
 
-    var json = JsonSerializer.Serialize(new
-    {
-      plaidInstitutionId = "id",
-      plaidAccountId = "id",
-      plaidAccountName = "Some Account",
-    });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, AddUri)
-    {
-      Content = content,
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeProblemDetails(HttpStatusCode.Unauthorized);
@@ -162,23 +133,17 @@ public class AddTests(TestApi testApi) : IntegrationTest(testApi)
       return user;
     }, TestContext.Current.CancellationToken);
 
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, user.Id.ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(AddUri)
+      .WithUserId(user.Id)
+      .WithBody(new
+      {
+        plaidInstitutionId = "id",
+        plaidAccountId = "id",
+        plaidAccountName = "Some Account",
+      })
       .Build();
 
-    var json = JsonSerializer.Serialize(new
-    {
-      plaidInstitutionId = "id",
-      plaidAccountId = "id",
-      plaidAccountName = "Some Account",
-    });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, AddUri)
-    {
-      Content = content,
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeValidationProblemDetails(new Dictionary<string, string[]>()
@@ -216,23 +181,17 @@ public class AddTests(TestApi testApi) : IntegrationTest(testApi)
       return (user, institution, account);
     }, TestContext.Current.CancellationToken);
 
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, user.Id.ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(AddUri)
+      .WithUserId(user.Id)
+      .WithBody(new
+      {
+        plaidInstitutionId = ((PlaidMetadata)institution.Metadata!).PlaidId,
+        plaidAccountId = ((PlaidAccountMetadata)account.Metadata!).PlaidId,
+        plaidAccountName = ((PlaidAccountMetadata)account.Metadata).PlaidName,
+      })
       .Build();
 
-    var json = JsonSerializer.Serialize(new
-    {
-      plaidInstitutionId = ((PlaidMetadata)institution.Metadata!).PlaidId,
-      plaidAccountId = ((PlaidAccountMetadata)account.Metadata!).PlaidId,
-      plaidAccountName = ((PlaidAccountMetadata)account.Metadata).PlaidName,
-    });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, AddUri)
-    {
-      Content = content,
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeProblemDetails(HttpStatusCode.Conflict);
@@ -261,25 +220,19 @@ public class AddTests(TestApi testApi) : IntegrationTest(testApi)
       return (user, institution);
     }, TestContext.Current.CancellationToken);
 
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, user.Id.ToString())
-      .Build();
-
     var newAccountId = "newAccountId";
     var newAccountName = "New Account";
 
-    var json = JsonSerializer.Serialize(new
-    {
-      plaidInstitutionId = ((PlaidMetadata)institution.Metadata!).PlaidId,
-      plaidAccountId = newAccountId,
-      plaidAccountName = newAccountName,
-    });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, AddUri)
-    {
-      Content = content,
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
+    using var request = HttpRequestBuilder.New()
+      .Post(AddUri)
+      .WithUserId(user.Id)
+      .WithBody(new
+      {
+        plaidInstitutionId = ((PlaidMetadata)institution.Metadata!).PlaidId,
+        plaidAccountId = newAccountId,
+        plaidAccountName = newAccountName,
+      })
+      .Build();
 
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 

tests/FiscalOS.API.Tests/Integration/Auth/LoginTests.cs

@@ -1,22 +1,23 @@
-using FiscalOS.API.Tests.Common;
-
-namespace FiscalOS.API.Tests.Integration;
+namespace FiscalOS.API.Tests.Integration.Auth;
 
 public class LoginTests(TestApi testApi) : IntegrationTest(testApi)
 {
-  private static readonly Uri LoginUri = new("/login", UriKind.Relative);
+  private static readonly Uri LoginUri = new("/auth/login", UriKind.Relative);
 
   [Theory]
   [ClassData<LoginValidationTestCases>]
   public async Task Login_WhenUserSubmitsInvalidRequest_ItShouldReturn400WithProblemDetails(LoginValidationTestCase tc)
   {
-    var req = new
-    {
-      username = tc.Username,
-      password = tc.Password,
-    };
+    using var request = HttpRequestBuilder.New()
+      .Post(LoginUri)
+      .WithBody(new
+      {
+        username = tc.Username,
+        password = tc.Password,
+      })
+      .Build();
 
-    var res = await Client.PostAsJsonAsync(LoginUri, req, TestContext.Current.CancellationToken);
+    var res = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await res.Should().BeValidationProblemDetails(tc.ExpectedErrors);
   }
@@ -24,13 +25,16 @@ public class LoginTests(TestApi testApi) : IntegrationTest(testApi)
   [Fact]
   public async Task Login_WhenUserDoesNotExist_ItShouldReturn401WithProblemDetails()
   {
-    var req = new
-    {
-      username = "Test",
-      password = "@Password2",
-    };
+    using var request = HttpRequestBuilder.New()
+      .Post(LoginUri)
+      .WithBody(new
+      {
+        username = "Test",
+        password = "@Password2",
+      })
+      .Build();
 
-    var res = await Client.PostAsJsonAsync(LoginUri, req, TestContext.Current.CancellationToken);
+    var res = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await res.Should().BeProblemDetails(HttpStatusCode.Unauthorized);
   }
@@ -49,13 +53,16 @@ public class LoginTests(TestApi testApi) : IntegrationTest(testApi)
       await context.SaveChangesAsync(ct);
     }, TestContext.Current.CancellationToken);
 
-    var req = new
-    {
-      username = "Stevan",
-      password = "@Password2",
-    };
+    using var request = HttpRequestBuilder.New()
+      .Post(LoginUri)
+      .WithBody(new
+      {
+        username = "Stevan",
+        password = "@Password2",
+      })
+      .Build();
 
-    var res = await Client.PostAsJsonAsync(LoginUri, req, TestContext.Current.CancellationToken);
+    var res = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await res.Should().BeProblemDetails(HttpStatusCode.Unauthorized);
   }
@@ -74,16 +81,19 @@ public class LoginTests(TestApi testApi) : IntegrationTest(testApi)
       await context.SaveChangesAsync(ct);
     }, TestContext.Current.CancellationToken);
 
-    var req = new
-    {
-      username = "Stevan",
-      password = "@Password1",
-    };
+    using var request = HttpRequestBuilder.New()
+      .Post(LoginUri)
+      .WithBody(new
+      {
+        username = "Stevan",
+        password = "@Password1",
+      })
+      .Build();
 
-    var res = await Client.PostAsJsonAsync(LoginUri, req, TestContext.Current.CancellationToken);
+    var res = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     res.Should().HaveSetCookieHeader("fiscalos_refresh_cookie");
-    await res.Should().BeJsonContentOfType<Login.Response>(HttpStatusCode.OK);
+    await res.Should().BeJsonContentOfType<API.Auth.Login.Response>(HttpStatusCode.OK);
   }
 }
 

tests/FiscalOS.API.Tests/Integration/Auth/RefreshTests.cs

@@ -1,8 +1,8 @@
-namespace FiscalOS.API.Tests.Integration;
+namespace FiscalOS.API.Tests.Integration.Auth;
 
 public class RefreshTests(TestApi testApi) : IntegrationTest(testApi)
 {
-  private static readonly Uri RefreshUri = new("/refresh", UriKind.Relative);
+  private static readonly Uri RefreshUri = new("/auth/refresh", UriKind.Relative);
 
   [Fact]
   public async Task Refresh_WhenCalledWithNoAccessToken_ItShouldReturn401WithProblemDetails()
@@ -15,14 +15,12 @@ public class RefreshTests(TestApi testApi) : IntegrationTest(testApi)
   [Fact]
   public async Task Refresh_WhenCalledWithNonExistentRefreshToken_ItShouldReturn400WithProblemDetails()
   {
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(RefreshUri)
+      .WithUserId(Guid.NewGuid())
+      .WithRefreshCookie("nonexistenttoken")
       .Build();
 
-    using var request = new HttpRequestMessage(HttpMethod.Post, RefreshUri);
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-    request.Headers.Add("Cookie", "fiscalos_refresh_cookie=nonexistenttoken");
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeProblemDetails(HttpStatusCode.BadRequest);
@@ -53,14 +51,12 @@ public class RefreshTests(TestApi testApi) : IntegrationTest(testApi)
       return (new User[] { user1, user2 }, refreshToken1);
     }, TestContext.Current.CancellationToken);
 
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, users[0].Id.ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(RefreshUri)
+      .WithUserId(users[0].Id)
+      .WithRefreshCookie(refreshToken.Token)
       .Build();
 
-    using var request = new HttpRequestMessage(HttpMethod.Post, RefreshUri);
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-    request.Headers.Add("Cookie", $"fiscalos_refresh_cookie={refreshToken.Token}");
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeProblemDetails(HttpStatusCode.Forbidden);
@@ -98,14 +94,12 @@ public class RefreshTests(TestApi testApi) : IntegrationTest(testApi)
       return (user, refreshToken);
     }, TestContext.Current.CancellationToken);
 
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, user.Id.ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(RefreshUri)
+      .WithUserId(user.Id)
+      .WithRefreshCookie(refreshToken.Token)
       .Build();
 
-    using var request = new HttpRequestMessage(HttpMethod.Post, RefreshUri);
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-    request.Headers.Add("Cookie", $"fiscalos_refresh_cookie={refreshToken.Token}");
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeProblemDetails(HttpStatusCode.BadRequest);
@@ -132,14 +126,12 @@ public class RefreshTests(TestApi testApi) : IntegrationTest(testApi)
       return (user, refreshToken);
     }, TestContext.Current.CancellationToken);
 
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, user.Id.ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(RefreshUri)
+      .WithUserId(user.Id)
+      .WithRefreshCookie(refreshToken.Token)
       .Build();
 
-    using var request = new HttpRequestMessage(HttpMethod.Post, RefreshUri);
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-    request.Headers.Add("Cookie", $"fiscalos_refresh_cookie={refreshToken.Token}");
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeProblemDetails(HttpStatusCode.BadRequest);
@@ -168,19 +160,19 @@ public class RefreshTests(TestApi testApi) : IntegrationTest(testApi)
       return (user, refreshToken);
     }, TestContext.Current.CancellationToken);
 
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, user.Id.ToString())
-      .WithExpiresAt(DateTime.UtcNow.AddMinutes(accessTokenExpiresAtOffset))
+    using var request = HttpRequestBuilder.New()
+      .Post(RefreshUri)
+      .WithBearerToken(JwtTokenBuilder.New()
+        .WithClaim(JwtRegisteredClaimNames.Sub, user.Id.ToString())
+        .WithExpiresAt(DateTime.UtcNow.AddMinutes(accessTokenExpiresAtOffset))
+        .Build())
+      .WithRefreshCookie(refreshToken.Token)
       .Build();
 
-    using var request = new HttpRequestMessage(HttpMethod.Post, RefreshUri);
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-    request.Headers.Add("Cookie", $"fiscalos_refresh_cookie={refreshToken.Token}");
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     response.Should().HaveSetCookieHeader("fiscalos_refresh_cookie");
-    await response.Should().BeJsonContentOfType<Refresh.Response>(HttpStatusCode.OK);
+    await response.Should().BeJsonContentOfType<API.Auth.Refresh.Response>(HttpStatusCode.OK);
 
     var oldRefreshTokenInDb = await ExecuteAsync(
       async (context, ct) => await context.Set<RefreshToken>()

tests/FiscalOS.API.Tests/Integration/Institutions/ConnectTests.cs

@@ -1,15 +1,20 @@
 using Institution = FiscalOS.Core.Accounts.Institution;
 
-namespace FiscalOS.API.Tests.Integration;
+namespace FiscalOS.API.Tests.Integration.Institutions;
 
 public class ConnectTests(TestApi testApi) : IntegrationTest(testApi)
 {
-  private static readonly Uri ConnectUri = new("/accounts/connect", UriKind.Relative);
+  private static readonly Uri ConnectUri = new("/institutions/connect", UriKind.Relative);
 
   [Fact]
   public async Task Connect_WhenCalledWithoutValidToken_ItShouldReturn401WithProblemDetails()
   {
-    var res = await Client.PostAsJsonAsync(ConnectUri, new { }, TestContext.Current.CancellationToken);
+    using var request = HttpRequestBuilder.New()
+      .Post(ConnectUri)
+      .WithBody(new { })
+      .Build();
+
+    var res = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await res.Should().BeProblemDetails(HttpStatusCode.Unauthorized);
   }
@@ -17,17 +22,12 @@ public class ConnectTests(TestApi testApi) : IntegrationTest(testApi)
   [Fact]
   public async Task Connect_WhenCalledWithoutPublicTokenOrPlaidInstitutionId_ItShouldReturn400WithProblemDetails()
   {
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(ConnectUri)
+      .WithUserId(Guid.NewGuid())
+      .WithBody(new { })
       .Build();
 
-    using var content = new StringContent(JsonSerializer.Serialize(new { }), Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, ConnectUri)
-    {
-      Content = content,
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeValidationProblemDetails(new Dictionary<string, string[]>()
@@ -40,18 +40,12 @@ public class ConnectTests(TestApi testApi) : IntegrationTest(testApi)
   [Fact]
   public async Task Connect_WhenCalledWithoutPublicToken_ItShouldReturn400WithProblemDetails()
   {
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(ConnectUri)
+      .WithUserId(Guid.NewGuid())
+      .WithBody(new { plaidInstitutionId = "id" })
       .Build();
 
-    var json = JsonSerializer.Serialize(new { plaidInstitutionId = "id" });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, ConnectUri)
-    {
-      Content = content,
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeValidationProblemDetails(new Dictionary<string, string[]>()
@@ -63,18 +57,12 @@ public class ConnectTests(TestApi testApi) : IntegrationTest(testApi)
   [Fact]
   public async Task Connect_WhenCalledWithoutPlaidInstitutionId_ItShouldReturn400WithProblemDetails()
   {
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(ConnectUri)
+      .WithUserId(Guid.NewGuid())
+      .WithBody(new { publicToken = "token" })
       .Build();
 
-    var json = JsonSerializer.Serialize(new { publicToken = "token" });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, ConnectUri)
-    {
-      Content = content,
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeValidationProblemDetails(new Dictionary<string, string[]>()
@@ -86,22 +74,16 @@ public class ConnectTests(TestApi testApi) : IntegrationTest(testApi)
   [Fact]
   public async Task Connect_WhenCalledWithNonExistentUser_ItShouldReturn401WithProblemDetails()
   {
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, Guid.NewGuid().ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(ConnectUri)
+      .WithUserId(Guid.NewGuid())
+      .WithBody(new
+      {
+        publicToken = "token",
+        plaidInstitutionId = "id",
+      })
       .Build();
 
-    var json = JsonSerializer.Serialize(new
-    {
-      publicToken = "token",
-      plaidInstitutionId = "id",
-    });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, ConnectUri)
-    {
-      Content = content,
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeProblemDetails(HttpStatusCode.Unauthorized);
@@ -129,22 +111,16 @@ public class ConnectTests(TestApi testApi) : IntegrationTest(testApi)
       return (user, institution);
     }, TestContext.Current.CancellationToken);
 
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, user.Id.ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(ConnectUri)
+      .WithUserId(user.Id)
+      .WithBody(new
+      {
+        publicToken = "token",
+        plaidInstitutionId = ((PlaidMetadata)institution.Metadata!).PlaidId,
+      })
       .Build();
 
-    var json = JsonSerializer.Serialize(new
-    {
-      publicToken = "token",
-      plaidInstitutionId = ((PlaidMetadata)institution.Metadata!).PlaidId,
-    });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, ConnectUri)
-    {
-      Content = content,
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     await response.Should().BeProblemDetails(HttpStatusCode.Conflict);
@@ -176,22 +152,16 @@ public class ConnectTests(TestApi testApi) : IntegrationTest(testApi)
       return (user, publicTokenResponse.PublicToken);
     }, TestContext.Current.CancellationToken);
 
-    var jwt = JwtTokenBuilder.New()
-      .WithClaim(JwtRegisteredClaimNames.Sub, user.Id.ToString())
+    using var request = HttpRequestBuilder.New()
+      .Post(ConnectUri)
+      .WithUserId(user.Id)
+      .WithBody(new
+      {
+        publicToken,
+        plaidInstitutionId,
+      })
       .Build();
 
-    var json = JsonSerializer.Serialize(new
-    {
-      publicToken,
-      plaidInstitutionId,
-    });
-    using var content = new StringContent(json, Encoding.UTF8, "application/json");
-    using var request = new HttpRequestMessage(HttpMethod.Post, ConnectUri)
-    {
-      Content = content,
-    };
-    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", jwt);
-
     var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
 
     response.StatusCode.Should().Be(HttpStatusCode.OK);

tests/FiscalOS.API.Tests/Integration/Institutions/GetAvailableTests.cs

@@ -0,0 +1,114 @@
+using Institution = FiscalOS.Core.Accounts.Institution;
+
+namespace FiscalOS.API.Tests.Integration.Institutions;
+
+public class GetAvailableTests(TestApi testApi) : IntegrationTest(testApi)
+{
+  private static Uri GetAvailableUri(Guid id) => new($"/institutions/{id}/available", UriKind.Relative);
+
+  [Fact]
+  public async Task GetAvailable_WhenCalledAndUnauthenticated_ItShouldReturn401WithProblemDetails()
+  {
+    using var request = HttpRequestBuilder.New()
+      .WithUri(GetAvailableUri(Guid.NewGuid()))
+      .Build();
+
+    var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
+
+    await response.Should().BeProblemDetails(HttpStatusCode.Unauthorized);
+  }
+
+  [Fact]
+  public async Task GetAvailable_WhenCalledByNonExistentUser_ItShouldReturn401WithProblemDetails()
+  {
+    using var request = HttpRequestBuilder.New()
+      .WithUri(GetAvailableUri(Guid.NewGuid()))
+      .WithUserId(Guid.NewGuid())
+      .Build();
+
+    var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
+
+    await response.Should().BeProblemDetails(HttpStatusCode.Unauthorized);
+  }
+
+  [Fact]
+  public async Task GetAvailable_WhenCalledWithNonExistentInstitutionId_ItShouldReturn404WithProblemDetails()
+  {
+    var user = await ExecuteAsync(static async (context, ct, sp) =>
+    {
+      var passwordHasher = sp.GetRequiredService<IPasswordHasher>();
+      var encryptor = sp.GetRequiredService<IEncryptor>();
+
+      var userEncryptionKey = await encryptor.GenerateEncryptedKeyAsync(ct);
+      var user = User.From("Stevan", passwordHasher.Hash("@Password1"), userEncryptionKey);
+
+      context.Add(user);
+      await context.SaveChangesAsync(ct);
+      
+      return user;
+    }, TestContext.Current.CancellationToken);
+
+    using var request = HttpRequestBuilder.New()
+      .WithUri(GetAvailableUri(Guid.NewGuid()))
+      .WithUserId(user.Id)
+      .Build();
+
+    var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
+
+    await response.Should().BeProblemDetails(HttpStatusCode.NotFound);
+  }
+
+  [Fact]
+  public async Task GetAvailable_WhenCalledWithConnectedInstitution_ItShouldReturn200WithAvailableAccounts()
+  {
+    var (user, institution, expectedAccounts) = await ExecuteAsync(static async (context, ct, sp) =>
+    {
+      var passwordHasher = sp.GetRequiredService<IPasswordHasher>();
+      var encryptor = sp.GetRequiredService<IEncryptor>();
+      var plaidClient = sp.GetRequiredService<PlaidClient>();
+
+      var userEncryptionKey = await encryptor.GenerateEncryptedKeyAsync(ct);
+      var user = User.From("Stevan", passwordHasher.Hash("@Password1"), userEncryptionKey);
+
+      var institutionId = "ins_109508";
+
+      var publicTokenResponse = await plaidClient.SandboxPublicTokenCreateAsync(new()
+      {
+        InstitutionId = institutionId,
+        InitialProducts = [Products.Transactions],
+      });
+
+      var exchangeTokenResponse = await plaidClient.ItemPublicTokenExchangeAsync(new()
+      {
+        PublicToken = publicTokenResponse.PublicToken,
+      });
+
+      var accountsResponse = await plaidClient.AccountsGetAsync(new()
+      {
+        AccessToken = exchangeTokenResponse.AccessToken,
+      });
+      
+      var encryptedAccessToken = await encryptor.EncryptAsyncFor(user, exchangeTokenResponse.AccessToken, ct);
+      var institutionMetadata = PlaidMetadata.From(institutionId, "Some Bank", encryptedAccessToken);
+      var institution = Institution.From("Some Bank", institutionMetadata);
+
+      user.AddInstitution(institution);
+
+      context.Add(user);
+      context.Add(institution);
+      await context.SaveChangesAsync(ct);
+      
+      return (user, institution, accountsResponse.Accounts);
+    }, TestContext.Current.CancellationToken);
+
+    using var request = HttpRequestBuilder.New()
+      .WithUri(GetAvailableUri(institution.Id))
+      .WithUserId(user.Id)
+      .Build();
+
+    var response = await Client.SendAsync(request, TestContext.Current.CancellationToken);
+
+    (await response.Should().BeJsonContentOfType<List<Account>>(HttpStatusCode.OK))
+      .Which.Should().BeEquivalentTo(expectedAccounts);
+  }
+}

tests/FiscalOS.API.Tests/Usings.cs

@@ -27,6 +27,7 @@ global using Microsoft.AspNetCore.Mvc;
 global using Microsoft.AspNetCore.Mvc.Testing;
 global using Microsoft.AspNetCore.TestHost;
 global using Microsoft.EntityFrameworkCore;
+global using Microsoft.Extensions.Configuration;
 global using Microsoft.Extensions.DependencyInjection;
 global using Microsoft.Extensions.Logging;
 global using Microsoft.Extensions.Options;