Let users browse followers and following lists

Following lists are public; followers are visible to the user and to mutual followers. Adds GET /users/{id}/followers and /following, exposes isFollowing and canViewFollowers on the profile, and returns isFollowedByViewer from user search so the web player no longer calls /is-following per user.
2026-09-23 22:55:14 +02:00
parent b9a40186b1
commit cb046bba9e
26 changed files with 768 additions and 64 deletions
@@ -0,0 +1,30 @@
+using Microsoft.EntityFrameworkCore;
+using Musify.Application.Contracts;
+
+namespace Musify.Application.Users
+{
+    public static class FollowVisibility
+    {
+        public static async Task<bool> CanViewFollowersAsync(
+            IDatabase database,
+            long? viewerId,
+            long userId,
+            CancellationToken cancellationToken)
+        {
+            if (viewerId is not { } viewer)
+                return false;
+
+            if (viewer == userId)
+                return true;
+
+            var mutualRows = await database.UserFollows
+                .AsNoTracking()
+                .CountAsync(f =>
+                    (f.FollowerId == viewer && f.FollowedId == userId) ||
+                    (f.FollowerId == userId && f.FollowedId == viewer),
+                    cancellationToken);
+
+            return mutualRows == 2;
+        }
+    }
+}
@@ -0,0 +1,46 @@
+using ErrorOr;
+using Mediator;
+using Microsoft.EntityFrameworkCore;
+using Musify.Application.Contracts;
+using Musify.Application.Shared;
+using Musify.Application.Users.Responses;
+using X.PagedList.EF;
+
+namespace Musify.Application.Users
+{
+    public record GetUserFollowersQuery(long? ViewerId, long UserId, int PageNumber, int PageSize)
+        : IQuery<ErrorOr<PaginatedResponse<UserSummaryResponse>>>;
+
+    public class GetUserFollowersQueryHandler(IDatabase database)
+        : IQueryHandler<GetUserFollowersQuery, ErrorOr<PaginatedResponse<UserSummaryResponse>>>
+    {
+        public async ValueTask<ErrorOr<PaginatedResponse<UserSummaryResponse>>> Handle(GetUserFollowersQuery request, CancellationToken cancellationToken)
+        {
+            if (!await database.Users.AnyAsync(u => u.Id == request.UserId, cancellationToken))
+                return Error.NotFound();
+
+            if (!await FollowVisibility.CanViewFollowersAsync(database, request.ViewerId, request.UserId, cancellationToken))
+                return Error.Forbidden();
+
+            var followsQuery = database.UserFollows
+                .AsNoTracking()
+                .Where(f => f.FollowedId == request.UserId);
+
+            var totalCount = await followsQuery.CountAsync(cancellationToken);
+            var viewerId = request.ViewerId;
+
+            var page = await followsQuery
+                .OrderByDescending(f => f.CreatedAt)
+                .Select(f => new UserSummaryResponse(
+                    f.Follower.Id,
+                    f.Follower.Name,
+                    f.Follower.FirstName,
+                    f.Follower.SecondName,
+                    f.Follower.ProfilePictureUrl,
+                    viewerId != null && database.UserFollows.Any(v => v.FollowerId == viewerId && v.FollowedId == f.FollowerId)))
+                .ToPagedListAsync(request.PageNumber, request.PageSize, totalCount, cancellationToken);
+
+            return PaginatedResponse<UserSummaryResponse>.FromPagedList(page);
+        }
+    }
+}
@@ -0,0 +1,43 @@
+using ErrorOr;
+using Mediator;
+using Microsoft.EntityFrameworkCore;
+using Musify.Application.Contracts;
+using Musify.Application.Shared;
+using Musify.Application.Users.Responses;
+using X.PagedList.EF;
+
+namespace Musify.Application.Users
+{
+    public record GetUserFollowingQuery(long? ViewerId, long UserId, int PageNumber, int PageSize)
+        : IQuery<ErrorOr<PaginatedResponse<UserSummaryResponse>>>;
+
+    public class GetUserFollowingQueryHandler(IDatabase database)
+        : IQueryHandler<GetUserFollowingQuery, ErrorOr<PaginatedResponse<UserSummaryResponse>>>
+    {
+        public async ValueTask<ErrorOr<PaginatedResponse<UserSummaryResponse>>> Handle(GetUserFollowingQuery request, CancellationToken cancellationToken)
+        {
+            if (!await database.Users.AnyAsync(u => u.Id == request.UserId, cancellationToken))
+                return Error.NotFound();
+
+            var followsQuery = database.UserFollows
+                .AsNoTracking()
+                .Where(f => f.FollowerId == request.UserId);
+
+            var totalCount = await followsQuery.CountAsync(cancellationToken);
+            var viewerId = request.ViewerId;
+
+            var page = await followsQuery
+                .OrderByDescending(f => f.CreatedAt)
+                .Select(f => new UserSummaryResponse(
+                    f.Followed.Id,
+                    f.Followed.Name,
+                    f.Followed.FirstName,
+                    f.Followed.SecondName,
+                    f.Followed.ProfilePictureUrl,
+                    viewerId != null && database.UserFollows.Any(v => v.FollowerId == viewerId && v.FollowedId == f.FollowedId)))
+                .ToPagedListAsync(request.PageNumber, request.PageSize, totalCount, cancellationToken);
+
+            return PaginatedResponse<UserSummaryResponse>.FromPagedList(page);
+        }
+    }
+}
@@ -7,7 +7,7 @@ using Musify.Application.Serialization;

 namespace Musify.Application.Users
 {
-    public record GetUserProfileQuery(long UserId) : IQuery<ErrorOr<UserProfileResponse>>;
+    public record GetUserProfileQuery(long UserId, long? ViewerId = null) : IQuery<ErrorOr<UserProfileResponse>>;

    public record UserProfileResponse(
        [property: JsonConverter(typeof(LongAsStringConverter))] long Id,
@@ -17,7 +17,9 @@ namespace Musify.Application.Users
        string? ProfilePictureUrl,
        DateTime CreatedAt,
        int FollowersCount,
-        int FollowingCount);
+        int FollowingCount,
+        bool IsFollowing,
+        bool CanViewFollowers);

    public class GetUserProfileQueryHandler(IDatabase database)
        : IQueryHandler<GetUserProfileQuery, ErrorOr<UserProfileResponse>>
@@ -49,6 +51,14 @@ namespace Musify.Application.Users
                .AsNoTracking()
                .CountAsync(f => f.FollowerId == request.UserId, cancellationToken);

+            var isFollowing = request.ViewerId is { } viewerId && viewerId != request.UserId &&
+                await database.UserFollows
+                    .AsNoTracking()
+                    .AnyAsync(f => f.FollowerId == viewerId && f.FollowedId == request.UserId, cancellationToken);
+
+            var canViewFollowers = await FollowVisibility.CanViewFollowersAsync(
+                database, request.ViewerId, request.UserId, cancellationToken);
+
            return new UserProfileResponse(
                user.Id,
                user.Name,
@@ -57,7 +67,9 @@ namespace Musify.Application.Users
                user.ProfilePictureUrl,
                user.CreatedAt,
                followersCount,
-                followingCount);
+                followingCount,
+                isFollowing,
+                canViewFollowers);
        }
    }
 }
@@ -8,13 +8,13 @@ using Musify.Application.Contracts;

 namespace Musify.Application.Users
 {
-    public record GetUsersQuery(int PageNumber, int PageSize, string? UsernameSearch)
-        : IQuery<ErrorOr<PaginatedResponse<UserApplicationResponse>>>;
+    public record GetUsersQuery(int PageNumber, int PageSize, string? UsernameSearch, long? ViewerId = null)
+        : IQuery<ErrorOr<PaginatedResponse<UserSummaryResponse>>>;

    public class GetUsersQueryHandler(IDatabase database)
-        : IQueryHandler<GetUsersQuery, ErrorOr<PaginatedResponse<UserApplicationResponse>>>
+        : IQueryHandler<GetUsersQuery, ErrorOr<PaginatedResponse<UserSummaryResponse>>>
    {
-        public async ValueTask<ErrorOr<PaginatedResponse<UserApplicationResponse>>> Handle(GetUsersQuery request, CancellationToken cancellationToken)
+        public async ValueTask<ErrorOr<PaginatedResponse<UserSummaryResponse>>> Handle(GetUsersQuery request, CancellationToken cancellationToken)
        {
            var usersQuery = database.Users
                .AsNoTracking()
@@ -27,11 +27,19 @@ namespace Musify.Application.Users
            }

            var totalCount = await usersQuery.CountAsync(cancellationToken);
+            var viewerId = request.ViewerId;
            var pagedUsers = await usersQuery
-                .Select(u => UserApplicationResponse.FromEntity(u))
+                .OrderBy(u => u.Name)
+                .Select(u => new UserSummaryResponse(
+                    u.Id,
+                    u.Name,
+                    u.FirstName,
+                    u.SecondName,
+                    u.ProfilePictureUrl,
+                    viewerId != null && database.UserFollows.Any(f => f.FollowerId == viewerId && f.FollowedId == u.Id)))
                .ToPagedListAsync(request.PageNumber, request.PageSize, totalCount, cancellationToken);

-            return PaginatedResponse<UserApplicationResponse>.FromPagedList(pagedUsers);
+            return PaginatedResponse<UserSummaryResponse>.FromPagedList(pagedUsers);
        }
    }
 }
@@ -0,0 +1,13 @@
+using System.Text.Json.Serialization;
+using Musify.Application.Serialization;
+
+namespace Musify.Application.Users.Responses
+{
+    public record UserSummaryResponse(
+        [property: JsonConverter(typeof(LongAsStringConverter))] long Id,
+        string Name,
+        string? FirstName,
+        string? SecondName,
+        string? ProfilePictureUrl,
+        bool IsFollowedByViewer);
+}
@@ -21,7 +21,7 @@ public static class UserEndpoints
        group.MapGet("/", GetUsers)
            .WithName("GetUsers")
            .WithSummary("Get Paginated Users.")
-            .Produces<PaginatedResponse<UserApplicationResponse>>();
+            .Produces<PaginatedResponse<UserSummaryResponse>>();

        group.MapGet("/{id}", GetUserById)
            .WithName("GetUserById")
@@ -52,6 +52,19 @@ public static class UserEndpoints
            .Produces<UserProfileResponse>()
            .Produces(StatusCodes.Status404NotFound);

+        group.MapGet("/{id}/followers", GetFollowers)
+            .WithName("GetUserFollowers")
+            .WithSummary("Get The Users Following A User. Visible To The User And To Mutual Followers.")
+            .Produces<PaginatedResponse<UserSummaryResponse>>()
+            .Produces(StatusCodes.Status403Forbidden)
+            .Produces(StatusCodes.Status404NotFound);
+
+        group.MapGet("/{id}/following", GetFollowing)
+            .WithName("GetUserFollowing")
+            .WithSummary("Get The Users A User Follows.")
+            .Produces<PaginatedResponse<UserSummaryResponse>>()
+            .Produces(StatusCodes.Status404NotFound);
+
        group.MapGet("/{id}/is-following", IsFollowing)
            .WithName("IsFollowingUser")
            .WithSummary("Check Whether The Current User Follows Another User.")
@@ -88,12 +101,13 @@ public static class UserEndpoints

    private static async Task<IResult> GetUsers(
        IMediator mediator,
+        CurrentUser currentUser,
        CancellationToken cancellationToken,
        string? usernameSearch,
        int pageNumber = 1,
        int pageSize = 10)
    {
-        var result = await mediator.Send(new GetUsersQuery(pageNumber, pageSize, usernameSearch), cancellationToken);
+        var result = await mediator.Send(new GetUsersQuery(pageNumber, pageSize, usernameSearch, currentUser.Id), cancellationToken);
        return result.ToHttpResult();
    }

@@ -133,10 +147,35 @@ public static class UserEndpoints

    private static async Task<IResult> GetUserProfile(
        IMediator mediator,
+        CurrentUser currentUser,
        long id,
        CancellationToken cancellationToken)
    {
-        var result = await mediator.Send(new GetUserProfileQuery(id), cancellationToken);
+        var result = await mediator.Send(new GetUserProfileQuery(id, currentUser.Id), cancellationToken);
+        return result.ToHttpResult();
+    }
+
+    private static async Task<IResult> GetFollowers(
+        IMediator mediator,
+        CurrentUser currentUser,
+        long id,
+        CancellationToken cancellationToken,
+        int pageNumber = 1,
+        int pageSize = 20)
+    {
+        var result = await mediator.Send(new GetUserFollowersQuery(currentUser.Id, id, pageNumber, pageSize), cancellationToken);
+        return result.ToHttpResult();
+    }
+
+    private static async Task<IResult> GetFollowing(
+        IMediator mediator,
+        CurrentUser currentUser,
+        long id,
+        CancellationToken cancellationToken,
+        int pageNumber = 1,
+        int pageSize = 20)
+    {
+        var result = await mediator.Send(new GetUserFollowingQuery(currentUser.Id, id, pageNumber, pageSize), cancellationToken);
        return result.ToHttpResult();
    }

@@ -0,0 +1,95 @@
+using ErrorOr;
+using Musify.Application.Shared;
+using Musify.Application.Tests.TestSupport;
+using Musify.Application.Users;
+using Musify.Application.Users.Responses;
+using Musify.Domain.Entities;
+using Xunit;
+
+namespace Musify.Application.Tests.Users
+{
+    public sealed class GetUserFollowersQueryHandlerTests : HandlerTestBase
+    {
+        private GetUserFollowersQueryHandler CreateHandler() => new(Database);
+
+        private async Task<ErrorOr<PaginatedResponse<UserSummaryResponse>>> Send(long? viewerId, long userId) =>
+            await CreateHandler().Handle(new GetUserFollowersQuery(viewerId, userId, 1, 20), TestContext.Current.CancellationToken);
+
+        [Fact]
+        public async Task Handle_OwnProfile_ReturnsFollowers()
+        {
+            var user = TestEntities.User(1, "user");
+            var follower = TestEntities.User(2, "follower");
+            await SeedAsync(user, follower, new UserFollow { FollowerId = follower.Id, FollowedId = user.Id });
+
+            var result = await Send(user.Id, user.Id);
+
+            Assert.False(result.IsError);
+            var item = Assert.Single(result.Value.Items);
+            Assert.Equal(follower.Id, item.Id);
+            Assert.False(item.IsFollowedByViewer);
+        }
+
+        [Fact]
+        public async Task Handle_MutualFollow_ReturnsFollowersWithViewerFollowState()
+        {
+            var viewer = TestEntities.User(1, "viewer");
+            var user = TestEntities.User(2, "user");
+            var other = TestEntities.User(3, "other");
+            await SeedAsync(
+                viewer, user, other,
+                new UserFollow { FollowerId = viewer.Id, FollowedId = user.Id },
+                new UserFollow { FollowerId = user.Id, FollowedId = viewer.Id },
+                new UserFollow { FollowerId = other.Id, FollowedId = user.Id },
+                new UserFollow { FollowerId = viewer.Id, FollowedId = other.Id });
+
+            var result = await Send(viewer.Id, user.Id);
+
+            Assert.False(result.IsError);
+            Assert.Equal(2, result.Value.TotalItemCount);
+            Assert.All(result.Value.Items, item => Assert.Equal(item.Id == other.Id, item.IsFollowedByViewer));
+        }
+
+        [Fact]
+        public async Task Handle_ViewerFollowsButNotFollowedBack_ReturnsForbidden()
+        {
+            var viewer = TestEntities.User(1, "viewer");
+            var user = TestEntities.User(2, "user");
+            await SeedAsync(viewer, user, new UserFollow { FollowerId = viewer.Id, FollowedId = user.Id });
+
+            var result = await Send(viewer.Id, user.Id);
+
+            Assert.Equal(ErrorType.Forbidden, result.FirstError.Type);
+        }
+
+        [Fact]
+        public async Task Handle_FollowedByUserButNotFollowingBack_ReturnsForbidden()
+        {
+            var viewer = TestEntities.User(1, "viewer");
+            var user = TestEntities.User(2, "user");
+            await SeedAsync(viewer, user, new UserFollow { FollowerId = user.Id, FollowedId = viewer.Id });
+
+            var result = await Send(viewer.Id, user.Id);
+
+            Assert.Equal(ErrorType.Forbidden, result.FirstError.Type);
+        }
+
+        [Fact]
+        public async Task Handle_Anonymous_ReturnsForbidden()
+        {
+            await SeedAsync(TestEntities.User(1, "user"));
+
+            var result = await Send(null, 1);
+
+            Assert.Equal(ErrorType.Forbidden, result.FirstError.Type);
+        }
+
+        [Fact]
+        public async Task Handle_UserMissing_ReturnsNotFound()
+        {
+            var result = await Send(1, 404);
+
+            Assert.Equal(ErrorType.NotFound, result.FirstError.Type);
+        }
+    }
+}
@@ -0,0 +1,75 @@
+using ErrorOr;
+using Musify.Application.Tests.TestSupport;
+using Musify.Application.Users;
+using Musify.Domain.Entities;
+using Xunit;
+
+namespace Musify.Application.Tests.Users
+{
+    public sealed class GetUserFollowingQueryHandlerTests : HandlerTestBase
+    {
+        private GetUserFollowingQueryHandler CreateHandler() => new(Database);
+
+        [Fact]
+        public async Task Handle_Anonymous_ReturnsFollowedUsers()
+        {
+            var user = TestEntities.User(1, "user");
+            var followedA = TestEntities.User(2, "followedA");
+            var followedB = TestEntities.User(3, "followedB");
+            await SeedAsync(
+                user, followedA, followedB,
+                new UserFollow { FollowerId = user.Id, FollowedId = followedA.Id },
+                new UserFollow { FollowerId = user.Id, FollowedId = followedB.Id });
+
+            var result = await CreateHandler().Handle(new GetUserFollowingQuery(null, user.Id, 1, 20), TestContext.Current.CancellationToken);
+
+            Assert.False(result.IsError);
+            Assert.Equal(2, result.Value.TotalItemCount);
+            Assert.All(result.Value.Items, item => Assert.False(item.IsFollowedByViewer));
+        }
+
+        [Fact]
+        public async Task Handle_Viewer_MarksUsersTheViewerFollows()
+        {
+            var viewer = TestEntities.User(1, "viewer");
+            var user = TestEntities.User(2, "user");
+            var followedA = TestEntities.User(3, "followedA");
+            var followedB = TestEntities.User(4, "followedB");
+            await SeedAsync(
+                viewer, user, followedA, followedB,
+                new UserFollow { FollowerId = user.Id, FollowedId = followedA.Id },
+                new UserFollow { FollowerId = user.Id, FollowedId = followedB.Id },
+                new UserFollow { FollowerId = viewer.Id, FollowedId = followedA.Id });
+
+            var result = await CreateHandler().Handle(new GetUserFollowingQuery(viewer.Id, user.Id, 1, 20), TestContext.Current.CancellationToken);
+
+            Assert.False(result.IsError);
+            Assert.All(result.Value.Items, item => Assert.Equal(item.Id == followedA.Id, item.IsFollowedByViewer));
+        }
+
+        [Fact]
+        public async Task Handle_Pagination_ReturnsRequestedPage()
+        {
+            await SeedAsync(
+                TestEntities.User(1, "user"), TestEntities.User(2, "a"), TestEntities.User(3, "b"), TestEntities.User(4, "c"),
+                new UserFollow { FollowerId = 1, FollowedId = 2 },
+                new UserFollow { FollowerId = 1, FollowedId = 3 },
+                new UserFollow { FollowerId = 1, FollowedId = 4 });
+
+            var result = await CreateHandler().Handle(new GetUserFollowingQuery(null, 1, 2, 2), TestContext.Current.CancellationToken);
+
+            Assert.False(result.IsError);
+            Assert.Single(result.Value.Items);
+            Assert.Equal(3, result.Value.TotalItemCount);
+            Assert.False(result.Value.HasNextPage);
+        }
+
+        [Fact]
+        public async Task Handle_UserMissing_ReturnsNotFound()
+        {
+            var result = await CreateHandler().Handle(new GetUserFollowingQuery(null, 404, 1, 20), TestContext.Current.CancellationToken);
+
+            Assert.Equal(ErrorType.NotFound, result.FirstError.Type);
+        }
+    }
+}
@@ -30,6 +30,46 @@ namespace Musify.Application.Tests.Users
            Assert.Equal(1, result.Value.FollowingCount);
        }

+        [Fact]
+        public async Task Handle_MutualFollow_ViewerCanSeeFollowersAndIsFollowing()
+        {
+            var viewer = TestEntities.User(1, "viewer");
+            var user = TestEntities.User(2, "user");
+            await SeedAsync(
+                viewer, user,
+                new UserFollow { FollowerId = viewer.Id, FollowedId = user.Id },
+                new UserFollow { FollowerId = user.Id, FollowedId = viewer.Id });
+
+            var result = await CreateHandler().Handle(new GetUserProfileQuery(user.Id, viewer.Id), TestContext.Current.CancellationToken);
+
+            Assert.True(result.Value.IsFollowing);
+            Assert.True(result.Value.CanViewFollowers);
+        }
+
+        [Fact]
+        public async Task Handle_OneWayFollow_ViewerCannotSeeFollowers()
+        {
+            var viewer = TestEntities.User(1, "viewer");
+            var user = TestEntities.User(2, "user");
+            await SeedAsync(viewer, user, new UserFollow { FollowerId = viewer.Id, FollowedId = user.Id });
+
+            var result = await CreateHandler().Handle(new GetUserProfileQuery(user.Id, viewer.Id), TestContext.Current.CancellationToken);
+
+            Assert.True(result.Value.IsFollowing);
+            Assert.False(result.Value.CanViewFollowers);
+        }
+
+        [Fact]
+        public async Task Handle_OwnProfile_CanSeeFollowersButIsNotFollowing()
+        {
+            await SeedAsync(TestEntities.User(1, "user"));
+
+            var result = await CreateHandler().Handle(new GetUserProfileQuery(1, 1), TestContext.Current.CancellationToken);
+
+            Assert.False(result.Value.IsFollowing);
+            Assert.True(result.Value.CanViewFollowers);
+        }
+
        [Fact]
        public async Task Handle_UserMissing_ReturnsNotFound()
        {
@@ -1,5 +1,6 @@
 using Musify.Application.Tests.TestSupport;
 using Musify.Application.Users;
+using Musify.Domain.Entities;
 using Xunit;

 namespace Musify.Application.Tests.Users
@@ -30,5 +31,18 @@ namespace Musify.Application.Tests.Users
            var user = Assert.Single(result.Value.Items);
            Assert.Equal(1, user.Id);
        }
+
+        [Fact]
+        public async Task Handle_Viewer_MarksFollowedUsers()
+        {
+            await SeedAsync(
+                TestEntities.User(1, "viewer"), TestEntities.User(2, "alice"), TestEntities.User(3, "bob"),
+                new UserFollow { FollowerId = 1, FollowedId = 2 });
+
+            var result = await CreateHandler().Handle(new GetUsersQuery(PageNumber: 1, PageSize: 10, UsernameSearch: null, ViewerId: 1), TestContext.Current.CancellationToken);
+
+            Assert.False(result.IsError);
+            Assert.All(result.Value.Items, item => Assert.Equal(item.Id == 2, item.IsFollowedByViewer));
+        }
    }
 }