♻️ Refactored activities

DysonNetwork.Sphere/Account/AccountEventService.cs

@@ -13,7 +13,6 @@ namespace DysonNetwork.Sphere.Account;
 
 public class AccountEventService(
     AppDatabase db,
-    ActivityService act,
     WebSocketService ws,
     ICacheService cache,
     PaymentService payment,
@@ -86,13 +85,6 @@ public class AccountEventService(
         db.AccountStatuses.Add(status);
         await db.SaveChangesAsync();
 
-        await act.CreateActivity(
-            user,
-            "accounts.status",
-            $"account.statuses/{status.Id}",
-            ActivityVisibility.Friends
-        );
-
         return status;
     }
 
@@ -220,13 +212,6 @@ public class AccountEventService(
         db.AccountCheckInResults.Add(result);
         await db.SaveChangesAsync();  // Don't forget to save changes to the database
 
-        await act.CreateActivity(
-            user,
-            "accounts.check-in",
-            $"account.check-in/{result.Id}",
-            ActivityVisibility.Friends
-        );
-
         // The lock will be automatically released by the await using statement
         return result;
     }

DysonNetwork.Sphere/Activity/Activity.cs

@@ -1,26 +1,37 @@
 using System.ComponentModel.DataAnnotations;
 using System.ComponentModel.DataAnnotations.Schema;
+using NodaTime;
 
 namespace DysonNetwork.Sphere.Activity;
 
-public enum ActivityVisibility
+public interface IActivity
 {
-    Public,
+    public Activity ToActivity();
-    Friends,
-    Selected
 }
 
+[NotMapped]
 public class Activity : ModelBase
 {
-    public Guid Id { get; set; } = Guid.NewGuid();
+    public Guid Id { get; set; }
     [MaxLength(1024)] public string Type { get; set; } = null!;
     [MaxLength(4096)] public string ResourceIdentifier { get; set; } = null!;
-    public ActivityVisibility Visibility { get; set; } = ActivityVisibility.Public;
     [Column(TypeName = "jsonb")] public Dictionary<string, object> Meta { get; set; } = new();
-    [Column(TypeName = "jsonb")] public ICollection<Guid> UsersVisible { get; set; } = new List<Guid>();
 
-    public Guid AccountId { get; set; }
+    public object? Data { get; set; }
-    public Account.Account Account { get; set; } = null!;
 
-    [NotMapped] public object? Data { get; set; }
+    // Outdated fields, for backward compability
+    public int Visibility => 0;
+
+    public static Activity Empty()
+    {
+        var now = SystemClock.Instance.GetCurrentInstant();
+        return new Activity
+        {
+            CreatedAt = now,
+            UpdatedAt = now,
+            Id = Guid.NewGuid(),
+            Type = "empty",
+            ResourceIdentifier = "none"
+        };
+    }
 }

DysonNetwork.Sphere/Activity/ActivityController.cs

@@ -1,38 +1,38 @@
 using DysonNetwork.Sphere.Account;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.EntityFrameworkCore;
+using NodaTime;
 
 namespace DysonNetwork.Sphere.Activity;
 
+/// <summary>
+/// Activity is a universal feed that contains multiple kinds of data. Personalized and generated dynamically.
+/// </summary>
 [ApiController]
 [Route("/activities")]
 public class ActivityController(
-    AppDatabase db,
+    ActivityService acts
-    ActivityReaderService reader,
+) : ControllerBase
-    RelationshipService rels) : ControllerBase
 {
+    /// <summary>
+    /// Listing the activities for the user, users may be logged in or not to use this API.
+    /// When the users are not logged in, this API will return the posts that are public.
+    /// When the users are logged in,
+    /// the API will personalize the user's experience
+    /// by ranking up the people they like and the posts they like.
+    /// Besides, when users are logged in, it will also mix the other kinds of data and who're plying to them.
+    /// </summary>
     [HttpGet]
-    public async Task<ActionResult<List<Activity>>> ListActivities([FromQuery] int offset, [FromQuery] int take = 20)
+    public async Task<ActionResult<List<Activity>>> ListActivities([FromQuery] int? cursor, [FromQuery] int take = 20)
     {
+        var cursorTimestamp = cursor is <= 1000
+            ? SystemClock.Instance.GetCurrentInstant()
+            : Instant.FromUnixTimeMilliseconds(cursor!.Value);
+
         HttpContext.Items.TryGetValue("CurrentUser", out var currentUserValue);
-        var currentUser = currentUserValue as Account.Account;
+        if (currentUserValue is not Account.Account currentUser)
-        var userFriends = currentUser is null ? [] : await rels.ListAccountFriends(currentUser);
+            return Ok(await acts.GetActivitiesForAnyone(take, cursorTimestamp));
 
-        var totalCount = await db.Activities
+        return Ok(await acts.GetActivities(take, cursorTimestamp, currentUser));
-            .FilterWithVisibility(currentUser, userFriends)
-            .CountAsync();
-        var activities = await db.Activities
-            .Include(e => e.Account)
-            .Include(e => e.Account.Profile)
-            .FilterWithVisibility(currentUser, userFriends)
-            .OrderByDescending(e => e.CreatedAt)
-            .Skip(offset)
-            .Take(take)
-            .ToListAsync();
-        activities = await reader.LoadActivityData(activities, currentUser, userFriends);
-
-        Response.Headers["X-Total"] = totalCount.ToString();
-
-        return Ok(activities);
     }
 }

DysonNetwork.Sphere/Activity/ActivityService.cs

@@ -1,173 +1,62 @@
+using DysonNetwork.Sphere.Account;
 using DysonNetwork.Sphere.Post;
 using Microsoft.EntityFrameworkCore;
+using NodaTime;
 
 namespace DysonNetwork.Sphere.Activity;
 
-public class ActivityReaderService(AppDatabase db, PostService ps)
+public class ActivityService(AppDatabase db, RelationshipService rels)
 {
-    public async Task<List<Activity>> LoadActivityData(List<Activity> input, Account.Account? currentUser,
+    public async Task<List<Activity>> GetActivitiesForAnyone(int take, Instant cursor)
-        List<Guid> userFriends)
     {
-        if (input.Count == 0) return input;
+        var activities = new List<Activity>();
+        
+        // Crunching up data
+        var posts = await db.Posts
+            .Include(e => e.RepliedPost)
+            .Include(e => e.ForwardedPost)
+            .Include(e => e.Categories)
+            .Include(e => e.Tags)
+            .Where(e => e.RepliedPostId == null)
+            .Where(p => p.CreatedAt > cursor)
+            .FilterWithVisibility(null, [], isListing: true)
+            .Take(take)
+            .ToListAsync();
+        
+        // Formatting data
+        foreach (var post in posts)
+            activities.Add(post.ToActivity());
 
-        var postsId = input
+        return activities;
-            .Where(e => e.ResourceIdentifier.StartsWith("posts/"))
-            .Select(e => Guid.Parse(e.ResourceIdentifier.Split("/").Last()))
-            .Distinct()
-            .ToList();
-        if (postsId.Count > 0)
-        {
-            var posts = await db.Posts.Where(e => postsId.Contains(e.Id))
-                .Include(e => e.ForwardedPost)
-                .Include(e => e.Categories)
-                .Include(e => e.Tags)
-                .FilterWithVisibility(currentUser, userFriends)
-                .ToListAsync();
-            posts = PostService.TruncatePostContent(posts);
-            posts = await ps.LoadPublishers(posts);
-
-            var reactionMaps = await ps.GetPostReactionMapBatch(postsId);
-            foreach (var post in posts)
-                post.ReactionsCount =
-                    reactionMaps.TryGetValue(post.Id, out var count) ? count : new Dictionary<string, int>();
-
-            var postsDict = posts.ToDictionary(p => p.Id);
-
-            foreach (var item in input)
-            {
-                var resourceIdentifier = item.ResourceIdentifier;
-                if (!resourceIdentifier.StartsWith("posts/")) continue;
-                var postId = Guid.Parse(resourceIdentifier.Split("/").Last());
-                if (postsDict.TryGetValue(postId, out var post) && item.Data is null)
-                {
-                    item.Data = post;
-                }
-            }
-        }
-
-        var statusesId = input
-            .Where(e => e.ResourceIdentifier.StartsWith("account.statuses/"))
-            .Select(e => Guid.Parse(e.ResourceIdentifier.Split("/").Last()))
-            .Distinct()
-            .ToList();
-        if (statusesId.Count > 0)
-        {
-            var statuses = await db.AccountStatuses.Where(e => statusesId.Contains(e.Id))
-                .Include(e => e.Account)
-                .Include(e => e.Account.Profile)
-                .ToListAsync();
-            var statusesDict = statuses.ToDictionary(p => p.Id);
-
-            foreach (var item in input)
-            {
-                var resourceIdentifier = item.ResourceIdentifier;
-                if (!resourceIdentifier.StartsWith("account.statuses/")) continue;
-                var statusId = Guid.Parse(resourceIdentifier.Split("/").Last());
-                if (statusesDict.TryGetValue(statusId, out var status) && item.Data is null)
-                {
-                    item.Data = status;
-                }
-            }
-        }
-
-        var checkInId = input
-            .Where(e => e.ResourceIdentifier.StartsWith("account.check-in/"))
-            .Select(e => Guid.Parse(e.ResourceIdentifier.Split("/").Last()))
-            .Distinct()
-            .ToList();
-        if (checkInId.Count > 0)
-        {
-            var checkIns = await db.AccountCheckInResults.Where(e => checkInId.Contains(e.Id))
-                .Include(e => e.Account)
-                .Include(e => e.Account.Profile)
-                .ToListAsync();
-            var checkInsDict = checkIns.ToDictionary(p => p.Id);
-
-            foreach (var item in input)
-            {
-                var resourceIdentifier = item.ResourceIdentifier;
-                if (!resourceIdentifier.StartsWith("account.check-in/")) continue;
-                var checkInResultId = Guid.Parse(resourceIdentifier.Split("/").Last());
-                if (checkInsDict.TryGetValue(checkInResultId, out var checkIn) && item.Data is null)
-                {
-                    item.Data = checkIn;
-                }
-            }
-        }
-
-        return input;
     }
-}
+    
-
+    public async Task<List<Activity>> GetActivities(int take, Instant cursor, Account.Account currentUser)
-public class ActivityService(AppDatabase db)
-{
-    public async Task<Activity> CreateActivity(
-        Account.Account user,
-        string type,
-        string identifier,
-        ActivityVisibility visibility = ActivityVisibility.Public,
-        List<Guid>? visibleUsers = null
-    )
     {
-        var activity = new Activity
+        var activities = new List<Activity>();
+        var userFriends = await rels.ListAccountFriends(currentUser);
+        
+        // Crunching data
+        var posts = await db.Posts
+            .Include(e => e.RepliedPost)
+            .Include(e => e.ForwardedPost)
+            .Include(e => e.Categories)
+            .Include(e => e.Tags)
+            .Where(e => e.RepliedPostId == null || e.RepliedPostId == currentUser.Id)
+            .Where(p => p.CreatedAt > cursor)
+            .FilterWithVisibility(currentUser, userFriends, isListing: true)
+            .Take(take)
+            .ToListAsync();
+        
+        // Formatting data
+        foreach (var post in posts)
+            activities.Add(post.ToActivity());
+
+        if (activities.Count == 0)
         {
-            Type = type,
+            var now = SystemClock.Instance.GetCurrentInstant();
-            ResourceIdentifier = identifier,
+            activities.Add(Activity.Empty());
-            Visibility = visibility,
-            AccountId = user.Id,
-            UsersVisible = visibleUsers ?? []
-        };
-
-        db.Activities.Add(activity);
-        await db.SaveChangesAsync();
-
-        return activity;
-    }
-
-    public async Task CreateNewPostActivity(Account.Account user, Post.Post post)
-    {
-        if (post.Visibility is PostVisibility.Unlisted or PostVisibility.Private) return;
-
-        var identifier = $"posts/{post.Id}";
-        if (post.RepliedPostId is not null)
-        {
-            var ogPost = await db.Posts
-                .Where(e => e.Id == post.RepliedPostId)
-                .Include(e => e.Publisher)
-                .FirstOrDefaultAsync();
-            if (ogPost?.Publisher.AccountId == null) return;
-            await CreateActivity(
-                user,
-                "posts.new.replies",
-                identifier,
-                ActivityVisibility.Selected,
-                [ogPost.Publisher.AccountId!.Value]
-            );
-            return;
         }
 
-        await CreateActivity(
+        return activities;
-            user,
-            "posts.new",
-            identifier,
-            post.Visibility == PostVisibility.Friends ? ActivityVisibility.Friends : ActivityVisibility.Public
-        );
-    }
-}
-
-public static class ActivityQueryExtensions
-{
-    public static IQueryable<Activity> FilterWithVisibility(this IQueryable<Activity> source,
-        Account.Account? currentUser, List<Guid> userFriends)
-    {
-        if (currentUser is null)
-            return source.Where(e => e.Visibility == ActivityVisibility.Public);
-
-        return source
-            .Where(e => e.Visibility != ActivityVisibility.Friends ||
-                        userFriends.Contains(e.AccountId) ||
-                        e.AccountId == currentUser.Id)
-            .Where(e => e.Visibility != ActivityVisibility.Selected ||
-                        EF.Functions.JsonExists(e.UsersVisible, currentUser.Id.ToString()));
     }
 }

DysonNetwork.Sphere/AppDatabase.cs

@@ -50,8 +50,6 @@ public class AppDatabase(
     public DbSet<Storage.CloudFile> Files { get; set; }
     public DbSet<Storage.CloudFileReference> FileReferences { get; set; }
 
-    public DbSet<Activity.Activity> Activities { get; set; }
-
     public DbSet<Publisher.Publisher> Publishers { get; set; }
     public DbSet<PublisherMember> PublisherMembers { get; set; }
     public DbSet<PublisherSubscription> PublisherSubscriptions { get; set; }

DysonNetwork.Sphere/Migrations/20250608152205_RemoveActivities.cs

@@ -0,0 +1,55 @@
+using System;
+using System.Collections.Generic;
+using Microsoft.EntityFrameworkCore.Migrations;
+using NodaTime;
+
+#nullable disable
+
+namespace DysonNetwork.Sphere.Migrations
+{
+    /// <inheritdoc />
+    public partial class RemoveActivities : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "activities");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "activities",
+                columns: table => new
+                {
+                    id = table.Column<Guid>(type: "uuid", nullable: false),
+                    account_id = table.Column<Guid>(type: "uuid", nullable: false),
+                    created_at = table.Column<Instant>(type: "timestamp with time zone", nullable: false),
+                    deleted_at = table.Column<Instant>(type: "timestamp with time zone", nullable: true),
+                    meta = table.Column<Dictionary<string, object>>(type: "jsonb", nullable: false),
+                    resource_identifier = table.Column<string>(type: "character varying(4096)", maxLength: 4096, nullable: false),
+                    type = table.Column<string>(type: "character varying(1024)", maxLength: 1024, nullable: false),
+                    updated_at = table.Column<Instant>(type: "timestamp with time zone", nullable: false),
+                    users_visible = table.Column<ICollection<Guid>>(type: "jsonb", nullable: false),
+                    visibility = table.Column<int>(type: "integer", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("pk_activities", x => x.id);
+                    table.ForeignKey(
+                        name: "fk_activities_accounts_account_id",
+                        column: x => x.account_id,
+                        principalTable: "accounts",
+                        principalColumn: "id",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateIndex(
+                name: "ix_activities_account_id",
+                table: "activities",
+                column: "account_id");
+        }
+    }
+}

DysonNetwork.Sphere/Migrations/AppDatabaseModelSnapshot.cs

@@ -727,64 +727,6 @@ namespace DysonNetwork.Sphere.Migrations
                     b.ToTable("account_statuses", (string)null);
                 });
 
-            modelBuilder.Entity("DysonNetwork.Sphere.Activity.Activity", b =>
-                {
-                    b.Property<Guid>("Id")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("uuid")
-                        .HasColumnName("id");
-
-                    b.Property<Guid>("AccountId")
-                        .HasColumnType("uuid")
-                        .HasColumnName("account_id");
-
-                    b.Property<Instant>("CreatedAt")
-                        .HasColumnType("timestamp with time zone")
-                        .HasColumnName("created_at");
-
-                    b.Property<Instant?>("DeletedAt")
-                        .HasColumnType("timestamp with time zone")
-                        .HasColumnName("deleted_at");
-
-                    b.Property<Dictionary<string, object>>("Meta")
-                        .IsRequired()
-                        .HasColumnType("jsonb")
-                        .HasColumnName("meta");
-
-                    b.Property<string>("ResourceIdentifier")
-                        .IsRequired()
-                        .HasMaxLength(4096)
-                        .HasColumnType("character varying(4096)")
-                        .HasColumnName("resource_identifier");
-
-                    b.Property<string>("Type")
-                        .IsRequired()
-                        .HasMaxLength(1024)
-                        .HasColumnType("character varying(1024)")
-                        .HasColumnName("type");
-
-                    b.Property<Instant>("UpdatedAt")
-                        .HasColumnType("timestamp with time zone")
-                        .HasColumnName("updated_at");
-
-                    b.Property<ICollection<Guid>>("UsersVisible")
-                        .IsRequired()
-                        .HasColumnType("jsonb")
-                        .HasColumnName("users_visible");
-
-                    b.Property<int>("Visibility")
-                        .HasColumnType("integer")
-                        .HasColumnName("visibility");
-
-                    b.HasKey("Id")
-                        .HasName("pk_activities");
-
-                    b.HasIndex("AccountId")
-                        .HasDatabaseName("ix_activities_account_id");
-
-                    b.ToTable("activities", (string)null);
-                });
-
             modelBuilder.Entity("DysonNetwork.Sphere.Auth.Challenge", b =>
                 {
                     b.Property<Guid>("Id")
@@ -2795,18 +2737,6 @@ namespace DysonNetwork.Sphere.Migrations
                     b.Navigation("Account");
                 });
 
-            modelBuilder.Entity("DysonNetwork.Sphere.Activity.Activity", b =>
-                {
-                    b.HasOne("DysonNetwork.Sphere.Account.Account", "Account")
-                        .WithMany()
-                        .HasForeignKey("AccountId")
-                        .OnDelete(DeleteBehavior.Cascade)
-                        .IsRequired()
-                        .HasConstraintName("fk_activities_accounts_account_id");
-
-                    b.Navigation("Account");
-                });
-
             modelBuilder.Entity("DysonNetwork.Sphere.Auth.Challenge", b =>
                 {
                     b.HasOne("DysonNetwork.Sphere.Account.Account", "Account")

DysonNetwork.Sphere/Post/Post.cs

@@ -1,6 +1,7 @@
 using System.ComponentModel.DataAnnotations;
 using System.ComponentModel.DataAnnotations.Schema;
 using System.Text.Json.Serialization;
+using DysonNetwork.Sphere.Activity;
 using DysonNetwork.Sphere.Storage;
 using NodaTime;
 using NpgsqlTypes;
@@ -22,7 +23,7 @@ public enum PostVisibility
     Private
 }
 
-public class Post : ModelBase, IIdentifiedResource
+public class Post : ModelBase, IIdentifiedResource, IActivity
 {
     public Guid Id { get; set; }
     [MaxLength(1024)] public string? Title { get; set; }
@@ -48,7 +49,7 @@ public class Post : ModelBase, IIdentifiedResource
     public Post? RepliedPost { get; set; }
     public Guid? ForwardedPostId { get; set; }
     public Post? ForwardedPost { get; set; }
-    
+
     // Outdated fields, keep for backward compability
     public ICollection<CloudFile> OutdatedAttachments { get; set; } = new List<CloudFile>();
     [Column(TypeName = "jsonb")] public List<CloudFileReferenceObject> Attachments { get; set; } = [];
@@ -67,6 +68,20 @@ public class Post : ModelBase, IIdentifiedResource
     [NotMapped] public bool IsTruncated = false;
 
     public string ResourceIdentifier => $"post/{Id}";
+
+    public Activity.Activity ToActivity()
+    {
+        return new Activity.Activity()
+        {
+            CreatedAt = CreatedAt,
+            UpdatedAt = UpdatedAt,
+            DeletedAt = DeletedAt,
+            Id = Id,
+            Type = RepliedPostId is null ? "posts.new" : "posts.new.replies",
+            ResourceIdentifier = ResourceIdentifier,
+            Data = null
+        };
+    }
 }
 
 public class PostTag : ModelBase

DysonNetwork.Sphere/Post/PostService.cs

@@ -13,7 +13,6 @@ public class PostService(
     AppDatabase db,
     FileService fs,
     FileReferenceService fileRefService,
-    ActivityService act,
     IStringLocalizer<NotificationResource> localizer,
     NotificationService nty,
     IServiceScopeFactory factory
@@ -107,8 +106,6 @@ public class PostService(
             }
         }
 
-        await act.CreateNewPostActivity(user, post);
-
         if (post.PublishedAt is not null && post.PublishedAt.Value.ToDateTimeUtc() <= DateTime.UtcNow)
             _ = Task.Run(async () =>
             {
@@ -341,8 +338,12 @@ public class PostService(
 
 public static class PostQueryExtensions
 {
-    public static IQueryable<Post> FilterWithVisibility(this IQueryable<Post> source, Account.Account? currentUser,
+    public static IQueryable<Post> FilterWithVisibility(
-        List<Guid> userFriends, bool isListing = false)
+        this IQueryable<Post> source,
+        Account.Account? currentUser,
+        List<Guid> userFriends,
+        bool isListing = false
+    )
     {
         var now = Instant.FromDateTimeUtc(DateTime.UtcNow);
 

DysonNetwork.Sphere/Program.cs

@@ -1,6 +1,4 @@
 using System.Globalization;
-using System.Net;
-using System.Text;
 using System.Text.Json;
 using System.Threading.RateLimiting;
 using DysonNetwork.Sphere;
@@ -22,23 +20,18 @@ using DysonNetwork.Sphere.Storage;
 using DysonNetwork.Sphere.Storage.Handlers;
 using DysonNetwork.Sphere.Wallet;
 using Microsoft.AspNetCore.HttpOverrides;
-using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.RateLimiting;
 using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Options;
 using Microsoft.OpenApi.Models;
 using NodaTime;
 using NodaTime.Serialization.SystemTextJson;
 using OpenTelemetry.Metrics;
 using OpenTelemetry.Trace;
 using Prometheus;
-using Prometheus.DotNetRuntime;
 using Prometheus.SystemMetrics;
 using Quartz;
 using StackExchange.Redis;
 using tusdotnet;
-using tusdotnet.Models;
-using tusdotnet.Models.Configuration;
 using tusdotnet.Stores;
 
 var builder = WebApplication.CreateBuilder(args);
@@ -213,7 +206,6 @@ builder.Services.AddScoped<FileReferenceMigrationService>();
 builder.Services.AddScoped<PublisherService>();
 builder.Services.AddScoped<PublisherSubscriptionService>();
 builder.Services.AddScoped<ActivityService>();
-builder.Services.AddScoped<ActivityReaderService>();
 builder.Services.AddScoped<PostService>();
 builder.Services.AddScoped<RealmService>();
 builder.Services.AddScoped<ChatRoomService>();