Allow time zone to be omitted when creating users via API

Since we now have a default user time zone configuration option, it no
longer makes sense to require that the time zone be specified when
creating a new user via the API or indeed on any call to
`IUserManager.CreateUser`.

Author: smfeest

src/Buttercup.Application.Tests/UserManagerTests.cs

@@ -2,6 +2,7 @@
 using Buttercup.TestUtils;
 using Microsoft.AspNetCore.Identity;
 using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Options;
 using Microsoft.Extensions.Time.Testing;
 using Moq;
 using Xunit;
@@ -13,6 +14,7 @@ public sealed class UserManagerTests : DatabaseTests<DatabaseCollection>
 {
     private readonly ModelFactory modelFactory = new();
 
+    private readonly GlobalizationOptions globalizationOptions;
     private readonly Mock<IPasswordHasher<User>> passwordHasherMock = new();
     private readonly Mock<IRandomTokenGenerator> randomTokenGeneratorMock = new();
     private readonly FakeTimeProvider timeProvider;
@@ -21,9 +23,15 @@ public sealed class UserManagerTests : DatabaseTests<DatabaseCollection>
     public UserManagerTests(DatabaseFixture<DatabaseCollection> databaseFixture)
         : base(databaseFixture)
     {
+        this.globalizationOptions = new GlobalizationOptions
+        {
+            DefaultUserTimeZone = this.modelFactory.NextString("default-time-zone"),
+        };
         this.timeProvider = new(this.modelFactory.NextDateTime());
+
         this.userManager = new(
             this.DatabaseFixture,
+            Options.Create(this.globalizationOptions),
             this.passwordHasherMock.Object,
             this.randomTokenGeneratorMock.Object,
             this.timeProvider);
@@ -87,6 +95,31 @@ public async Task CreateUser_Success(bool isAdmin)
         Assert.Equal(expectedAuditEntry, actualAuditEntry);
     }
 
+    [Fact]
+    public async Task CreateUser_NoTimeZoneSpecified()
+    {
+        var currentUser = this.modelFactory.BuildUser();
+        await this.DatabaseFixture.InsertEntities(currentUser);
+
+        this.randomTokenGeneratorMock.Setup(x => x.Generate(2)).Returns(
+            this.modelFactory.NextToken(8));
+
+        var id = await this.userManager.CreateUser(
+            new()
+            {
+                Name = this.modelFactory.NextString("name"),
+                Email = this.modelFactory.NextEmail(),
+                TimeZone = null,
+            },
+            currentUser.Id,
+            null);
+
+        using var dbContext = this.DatabaseFixture.CreateDbContext();
+
+        var user = await dbContext.Users.GetAsync(id);
+        Assert.Equal(this.globalizationOptions.DefaultUserTimeZone, user.TimeZone);
+    }
+
     [Fact]
     public async Task CreateUser_EmailNotUnique()
     {

src/Buttercup.Application/NewUserAttributes.cs

@@ -32,13 +32,16 @@ public sealed record NewUserAttributes
     /// <summary>
     /// Gets or sets the user's time zone.
     /// </summary>
+    /// <remarks>
+    /// If this property is left unspecified, the new user's time zone will be set to <see
+    /// cref="GlobalizationOptions.DefaultUserTimeZone"/>.
+    /// </remarks>
     /// <value>
     /// The user's time zone as a TZID (e.g. 'Europe/London').
     /// </value>
-    [Required(ErrorMessage = "Error_RequiredField")]
     [StringLength(50, ErrorMessage = "Error_TooManyCharacters")]
     [TimeZone(ErrorMessage = "Error_InvalidTimeZone")]
-    public string TimeZone { get; init; } = string.Empty;
+    public string? TimeZone { get; init; }
 
     /// <summary>
     /// Gets or sets a value indicating whether the user is an administrator.

src/Buttercup.Application/UserManager.cs

@@ -4,17 +4,20 @@
 using Microsoft.AspNetCore.Identity;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Query;
+using Microsoft.Extensions.Options;
 
 namespace Buttercup.Application;
 
 internal sealed class UserManager(
     IDbContextFactory<AppDbContext> dbContextFactory,
+    IOptions<GlobalizationOptions> globalizationOptions,
     IPasswordHasher<User> passwordHasher,
     IRandomTokenGenerator randomTokenGenerator,
     TimeProvider timeProvider)
     : IUserManager
 {
     private readonly IDbContextFactory<AppDbContext> dbContextFactory = dbContextFactory;
+    private readonly GlobalizationOptions globalizationOptions = globalizationOptions.Value;
     private readonly IPasswordHasher<User> passwordHasher = passwordHasher;
     private readonly IRandomTokenGenerator randomTokenGenerator = randomTokenGenerator;
     private readonly TimeProvider timeProvider = timeProvider;
@@ -28,7 +31,7 @@ public async Task<long> CreateUser(
             Name = attributes.Name,
             Email = attributes.Email,
             SecurityStamp = this.GenerateSecurityStamp(),
-            TimeZone = attributes.TimeZone,
+            TimeZone = attributes.TimeZone ?? this.globalizationOptions.DefaultUserTimeZone,
             IsAdmin = attributes.IsAdmin,
             Created = timestamp,
             Modified = timestamp,

src/Buttercup.Web.Tests/Api/CreateUserTests.cs

@@ -1,6 +1,7 @@
 using Buttercup.Application;
 using Buttercup.Web.TestUtils;
 using HotChocolate;
+using Microsoft.Extensions.Options;
 using Xunit;
 
 namespace Buttercup.Web.Api;
@@ -43,6 +44,9 @@ public async Task CreatingUser(bool isAdmin)
     [Fact]
     public async Task CreatingUserWithDefaultValues()
     {
+        var globalizationOptions =
+            this.AppFactory.Services.GetRequiredService<IOptions<GlobalizationOptions>>().Value;
+
         var currentUser = this.ModelFactory.BuildUser() with { IsAdmin = true };
         await this.DatabaseFixture.InsertEntities(currentUser);
 
@@ -52,14 +56,17 @@ public async Task CreatingUserWithDefaultValues()
         {
             Name = this.ModelFactory.NextString("name"),
             Email = this.ModelFactory.NextEmail(),
-            TimeZone = "America/New_York",
         };
 
         using var response = await PostCreateUserMutation(client, attributes);
         using var document = await response.Content.ReadAsJsonDocument();
 
         var createUserElement = ApiAssert.SuccessResponse(document).GetProperty("createUser");
-        Assert.False(createUserElement.GetProperty("user").GetProperty("isAdmin").GetBoolean());
+        var userElement = createUserElement.GetProperty("user");
+        Assert.Equal(
+            globalizationOptions.DefaultUserTimeZone,
+            userElement.GetProperty("timeZone").GetString());
+        Assert.False(userElement.GetProperty("isAdmin").GetBoolean());
         JsonAssert.ValueIsNull(createUserElement.GetProperty("errors"));
     }