[Feature] Thread user member & thread members pagination (#2580)

* initial commit

* return & update old method

* mark old method as obsolete

src/Discord.Net.Core/DiscordConfig.cs

@@ -214,5 +214,13 @@ namespace Discord
         ///     If set to <see langword="false"/>, this value will be "Discord#1234".
         /// </remarks>
         public bool FormatUsersInBidirectionalUnicode { get; set; } = true;
+
+        /// <summary> 
+        ///     Returns the max thread members allowed to be in a request. 
+        /// </summary>
+        /// <returns>
+        ///     The maximum number of thread members that can be gotten per-batch.
+        /// </returns>
+        public const int MaxThreadMembersPerBatch = 100;
     }
 }

src/Discord.Net.Core/Entities/Users/IThreadUser.cs

@@ -21,5 +21,10 @@ namespace Discord
         ///     Gets the guild this thread was created in.
         /// </summary>
         IGuild Guild { get; }
+
+        /// <summary>
+        ///     Gets the <see cref="IGuildUser"/> on the server this thread was created in.
+        /// </summary>
+        IGuildUser GuildUser { get; }
     }
 }

src/Discord.Net.Rest/API/Common/ThreadMember.cs

@@ -16,5 +16,8 @@ namespace Discord.API
 
         [JsonProperty("flags")]
         public int Flags { get; set; } // No enum type (yet?)
+
+        [JsonProperty("member")]
+        public Optional<GuildMember> GuildMember { get; set; }
     }
 }

src/Discord.Net.Rest/DiscordRestApiClient.cs

@@ -563,16 +563,23 @@ namespace Discord.API
 
             await SendAsync("DELETE", () => $"channels/{channelId}/thread-members/{userId}", bucket, options: options).ConfigureAwait(false);
         }
-
-        public async Task<ThreadMember[]> ListThreadMembersAsync(ulong channelId, RequestOptions options = null)
+        
+        public async Task<ThreadMember[]> ListThreadMembersAsync(ulong channelId, ulong? after = null, int? limit = null, RequestOptions options = null)
         {
             Preconditions.NotEqual(channelId, 0, nameof(channelId));
 
+            var query = "?with_member=true";
+
+            if (limit.HasValue)
+                query += $"&limit={limit}";
+            if (after.HasValue)
+                query += $"&after={after}";
+
             options = RequestOptions.CreateOrClone(options);
 
             var bucket = new BucketIds(channelId: channelId);
 
-            return await SendAsync<ThreadMember[]>("GET", () => $"channels/{channelId}/thread-members", bucket, options: options).ConfigureAwait(false);
+            return await SendAsync<ThreadMember[]>("GET", () => $"channels/{channelId}/thread-members{query}", bucket, options: options).ConfigureAwait(false);
         }
 
         public async Task<ThreadMember> GetThreadMemberAsync(ulong channelId, ulong userId, RequestOptions options = null)
@@ -583,8 +590,9 @@ namespace Discord.API
             options = RequestOptions.CreateOrClone(options);
 
             var bucket = new BucketIds(channelId: channelId);
+            var query = "?with_member=true";
 
-            return await SendAsync<ThreadMember>("GET", () => $"channels/{channelId}/thread-members/{userId}", bucket, options: options).ConfigureAwait(false);
+            return await SendAsync<ThreadMember>("GET", () => $"channels/{channelId}/thread-members/{userId}{query}", bucket, options: options).ConfigureAwait(false);
         }
 
         public async Task<ChannelThreads> GetActiveThreadsAsync(ulong guildId, RequestOptions options = null)
@@ -2524,7 +2532,7 @@ namespace Discord.API
             => await SendAsync<RoleConnectionMetadata[]>("GET", () => $"applications/{CurrentApplicationId}/role-connections/metadata", new BucketIds(), options: options).ConfigureAwait(false);
 
         public async Task<RoleConnectionMetadata[]> UpdateApplicationRoleConnectionMetadataRecordsAsync(RoleConnectionMetadata[] roleConnections, RequestOptions options = null)
-        => await SendJsonAsync <RoleConnectionMetadata[]>("PUT", () => $"applications/{CurrentApplicationId}/role-connections/metadata", roleConnections, new BucketIds(), options: options).ConfigureAwait(false);
+        => await SendJsonAsync<RoleConnectionMetadata[]>("PUT", () => $"applications/{CurrentApplicationId}/role-connections/metadata", roleConnections, new BucketIds(), options: options).ConfigureAwait(false);
 
         public async Task<RoleConnection> GetUserApplicationRoleConnectionAsync(ulong applicationId, RequestOptions options = null)
         => await SendAsync<RoleConnection>("GET", () => $"users/@me/applications/{applicationId}/role-connection", new BucketIds(), options: options);

src/Discord.Net.Rest/Entities/Channels/RestThreadChannel.cs

@@ -101,6 +101,17 @@ namespace Discord.Rest
         public new Task<RestThreadUser> GetUserAsync(ulong userId, RequestOptions options = null)
             => ThreadHelper.GetUserAsync(userId, this, Discord, options);
 
+        /// <summary>
+        ///     Gets a collection of users within this thread.
+        /// </summary>
+        /// <param name="limit">Sets the limit of the user count for each request. 100 by default.</param>
+        /// <returns>
+        ///     A task that represents the asynchronous get operation. The task result contains a collection of thread
+        ///     users found within this thread channel.
+        /// </returns>
+        public IAsyncEnumerable<IReadOnlyCollection<RestThreadUser>> GetThreadUsersAsync(int limit = DiscordConfig.MaxThreadMembersPerBatch, RequestOptions options = null)
+            => ThreadHelper.GetUsersAsync(this, Discord, limit, null, options);
+
         /// <summary>
         ///     Gets a collection of users within this thread.
         /// </summary>
@@ -109,8 +120,9 @@ namespace Discord.Rest
         ///     A task representing the asynchronous get operation. The task returns a
         ///     <see cref="IReadOnlyCollection{T}"/> of <see cref="RestThreadUser"/>'s.
         /// </returns>
+        [Obsolete("Please use GetThreadUsersAsync instead of this. Will be removed in next major version.", false)]
         public new async Task<IReadOnlyCollection<RestThreadUser>> GetUsersAsync(RequestOptions options = null)
-            => (await ThreadHelper.GetUsersAsync(this, Discord, options).ConfigureAwait(false)).ToImmutableArray();
+            => (await GetThreadUsersAsync(options: options).FlattenAsync()).ToImmutableArray();
 
         /// <inheritdoc/>
         public override async Task ModifyAsync(Action<TextChannelProperties> func, RequestOptions options = null)

src/Discord.Net.Rest/Entities/Channels/ThreadHelper.cs

@@ -85,11 +85,27 @@ namespace Discord.Rest
             return result.Threads.Select(x => RestThreadChannel.Create(client, channel.Guild, x)).ToImmutableArray();
         }
 
-        public static async Task<RestThreadUser[]> GetUsersAsync(IThreadChannel channel, BaseDiscordClient client, RequestOptions options = null)
+        public static IAsyncEnumerable<IReadOnlyCollection<RestThreadUser>> GetUsersAsync(IThreadChannel channel, BaseDiscordClient client, int limit = DiscordConfig.MaxThreadMembersPerBatch, ulong? afterId = null, RequestOptions options = null)
         {
-            var users = await client.ApiClient.ListThreadMembersAsync(channel.Id, options);
-
-            return users.Select(x => RestThreadUser.Create(client, channel.Guild, x, channel)).ToArray();
+            return new PagedAsyncEnumerable<RestThreadUser>(
+                limit,
+                async (info, ct) =>
+                {
+                    if (info.Position != null)
+                        afterId = info.Position.Value;
+                    var users = await client.ApiClient.ListThreadMembersAsync(channel.Id, afterId, limit, options);
+                    return users.Select(x => RestThreadUser.Create(client, channel.Guild, x, channel)).ToImmutableArray();
+                },
+                nextPage: (info, lastPage) =>
+                {
+                    if (lastPage.Count != limit)
+                        return false;
+                    info.Position = lastPage.Max(x => x.Id);
+                    return true;
+                },
+                start: afterId,
+                count: limit
+            );
         }
 
         public static async Task<RestThreadUser> GetUserAsync(ulong userId, IThreadChannel channel, BaseDiscordClient client, RequestOptions options = null)

src/Discord.Net.Rest/Entities/Users/RestThreadUser.cs

@@ -18,6 +18,9 @@ namespace Discord.Rest
         /// <inheritdoc/>
         public IGuild Guild { get; }
 
+        /// <inheritdoc cref="IThreadUser.GuildUser"/>
+        public RestGuildUser GuildUser { get; private set; }
+
         /// <inheritdoc/>
         public string Mention => MentionUtils.MentionUser(Id);
 
@@ -38,8 +41,13 @@ namespace Discord.Rest
         internal void Update(Model model)
         {
             ThreadJoinedAt = model.JoinTimestamp;
+            if(model.GuildMember.IsSpecified)
+                GuildUser = RestGuildUser.Create(Discord, Guild, model.GuildMember.Value);
         }
 
+        /// <inheritdoc />
+        IGuildUser IThreadUser.GuildUser => GuildUser;
+
         /// <summary>
         ///     Gets the guild user for this thread user.
         /// </summary>

src/Discord.Net.WebSocket/Entities/Channels/SocketThreadChannel.cs

@@ -172,7 +172,7 @@ namespace Discord.WebSocket
             return threadUsers.ToImmutableArray();
         }
 
-        internal SocketThreadUser AddOrUpdateThreadMember(ThreadMember model, SocketGuildUser guildMember)
+        internal SocketThreadUser AddOrUpdateThreadMember(ThreadMember model, SocketGuildUser guildMember = null)
         {
             if (_members.TryGetValue(model.UserId.Value, out SocketThreadUser member))
                 member.Update(model);
@@ -219,15 +219,21 @@ namespace Discord.WebSocket
         /// <returns>A task representing the asynchronous download operation.</returns>
         public async Task DownloadUsersAsync(RequestOptions options = null)
         {
-            var users = await Discord.ApiClient.ListThreadMembersAsync(Id, options);
+            var prevBatchCount = DiscordConfig.MaxThreadMembersPerBatch;
+            ulong? maxId = null;
 
-            lock (_downloadLock)
+            while (prevBatchCount == DiscordConfig.MaxThreadMembersPerBatch)
             {
-                foreach (var threadMember in users)
-                {
-                    var guildUser = Guild.GetUser(threadMember.UserId.Value);
+                var users = await Discord.ApiClient.ListThreadMembersAsync(Id, maxId, DiscordConfig.MaxThreadMembersPerBatch, options);
+                prevBatchCount = users.Length;
+                maxId = users.Max(x => x.UserId.GetValueOrDefault());
 
-                    AddOrUpdateThreadMember(threadMember, guildUser);
+                lock (_downloadLock)
+                {
+                    foreach (var threadMember in users)
+                    {
+                        AddOrUpdateThreadMember(threadMember);
+                    }
                 }
             }
         }

src/Discord.Net.WebSocket/Entities/Users/SocketThreadUser.cs

@@ -134,19 +134,21 @@ namespace Discord.WebSocket
         public DateTimeOffset? RequestToSpeakTimestamp
             => GuildUser.RequestToSpeakTimestamp;
 
-        private SocketGuildUser GuildUser { get; set; }
+        /// <inheritdoc cref="IThreadUser.GuildUser"/>
+        public SocketGuildUser GuildUser { get; private set; }
 
-        internal SocketThreadUser(SocketGuild guild, SocketThreadChannel thread, SocketGuildUser member, ulong userId)
+        internal SocketThreadUser(SocketGuild guild, SocketThreadChannel thread, ulong userId, SocketGuildUser member = null)
             : base(guild.Discord, userId)
         {
             Thread = thread;
             Guild = guild;
-            GuildUser = member;
+            if(member is not null)
+                GuildUser = member;
         }
 
-        internal static SocketThreadUser Create(SocketGuild guild, SocketThreadChannel thread, Model model, SocketGuildUser member)
+        internal static SocketThreadUser Create(SocketGuild guild, SocketThreadChannel thread, Model model, SocketGuildUser guildUser = null)
         {
-            var entity = new SocketThreadUser(guild, thread, member, model.UserId.Value);
+            var entity = new SocketThreadUser(guild, thread, model.UserId.Value, guildUser);
             entity.Update(model);
             return entity;
         }
@@ -154,7 +156,7 @@ namespace Discord.WebSocket
         internal static SocketThreadUser Create(SocketGuild guild, SocketThreadChannel thread, SocketGuildUser owner)
         {
             // this is used for creating the owner of the thread.
-            var entity = new SocketThreadUser(guild, thread, owner, owner.Id);
+            var entity = new SocketThreadUser(guild, thread,  owner.Id, owner);
             entity.Update(new Model
             {
                 JoinTimestamp = thread.CreatedAt,
@@ -165,6 +167,8 @@ namespace Discord.WebSocket
         internal void Update(Model model)
         {
             ThreadJoinedAt = model.JoinTimestamp;
+            if(model.GuildMember.IsSpecified)
+                GuildUser = Guild.AddOrUpdateUser(model.GuildMember.Value);
         }
 
         /// <inheritdoc/>
@@ -214,6 +218,9 @@ namespace Discord.WebSocket
         /// <inheritdoc/>
         IGuild IGuildUser.Guild => Guild;
 
+        /// <inheritdoc />
+        IGuildUser IThreadUser.GuildUser => GuildUser;
+
         /// <inheritdoc/>
         ulong IGuildUser.GuildId => Guild.Id;