Initial support for invite member count arg

src/Discord.Net.Core/Entities/Invites/IInvite.cs

@@ -1,4 +1,4 @@
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 
 namespace Discord
 {
@@ -22,6 +22,10 @@ namespace Discord
         ulong GuildId { get; }
         /// <summary> Gets the name of the guild this invite is linked to. </summary>
         string GuildName { get; }
+        /// <summary> Gets the approximated count of online members in the guild. </summary>
+        int? PresenceCount { get; }
+        /// <summary> Gets the approximated count of total members in the guild. </summary>
+        int? MemberCount { get; }
 
         /// <summary> Accepts this invite and joins the target guild. This will fail on bot accounts. </summary>
         Task AcceptAsync(RequestOptions options = null);

src/Discord.Net.Core/IDiscordClient.cs

@@ -27,7 +27,7 @@ namespace Discord
         Task<IReadOnlyCollection<IGuild>> GetGuildsAsync(CacheMode mode = CacheMode.AllowDownload, RequestOptions options = null);
         Task<IGuild> CreateGuildAsync(string name, IVoiceRegion region, Stream jpegIcon = null, RequestOptions options = null);
         
-        Task<IInvite> GetInviteAsync(string inviteId, RequestOptions options = null);
+        Task<IInvite> GetInviteAsync(string inviteId, bool withCount = false, RequestOptions options = null);
 
         Task<IUser> GetUserAsync(ulong id, CacheMode mode = CacheMode.AllowDownload, RequestOptions options = null);
         Task<IUser> GetUserAsync(string username, string discriminator, RequestOptions options = null);

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

@@ -1,4 +1,4 @@
-#pragma warning disable CS1591
+#pragma warning disable CS1591
 using Newtonsoft.Json;
 
 namespace Discord.API
@@ -11,5 +11,9 @@ namespace Discord.API
         public InviteGuild Guild { get; set; }
         [JsonProperty("channel")]
         public InviteChannel Channel { get; set; }
+        [JsonProperty("approximate_presence_count")]
+        public Optional<int?> PresenceCount { get; set; }
+        [JsonProperty("approximate_member_count")]
+        public Optional<int?> MemberCount { get; set; }
     }
 }

src/Discord.Net.Rest/API/Rest/GetInviteParams.cs

@@ -0,0 +1,10 @@
+using Newtonsoft.Json;
+
+namespace Discord.API.Rest
+{
+    internal class GetInviteParams
+    {
+        [JsonProperty("with_counts")]
+        public Optional<bool?> WithCounts { get; set; }
+    }
+}

src/Discord.Net.Rest/BaseDiscordClient.cs

@@ -148,7 +148,7 @@ namespace Discord.Rest
         Task<IReadOnlyCollection<IConnection>> IDiscordClient.GetConnectionsAsync(RequestOptions options)
             => Task.FromResult<IReadOnlyCollection<IConnection>>(ImmutableArray.Create<IConnection>());
 
-        Task<IInvite> IDiscordClient.GetInviteAsync(string inviteId, RequestOptions options)
+        Task<IInvite> IDiscordClient.GetInviteAsync(string inviteId, bool withCount, RequestOptions options)
             => Task.FromResult<IInvite>(null);
 
         Task<IGuild> IDiscordClient.GetGuildAsync(ulong id, CacheMode mode, RequestOptions options)

src/Discord.Net.Rest/ClientHelper.cs

@@ -51,9 +51,13 @@ namespace Discord.Rest
         }
         
         public static async Task<RestInvite> GetInviteAsync(BaseDiscordClient client,
-            string inviteId, RequestOptions options)
+            string inviteId, bool withCount, RequestOptions options)
         {
-            var model = await client.ApiClient.GetInviteAsync(inviteId, options).ConfigureAwait(false);
+            var args = new GetInviteParams
+            {
+                WithCounts = withCount
+            };
+            var model = await client.ApiClient.GetInviteAsync(inviteId, args, options).ConfigureAwait(false);
             if (model != null)
                 return RestInvite.Create(client, null, null, model);
             return null;

src/Discord.Net.Rest/DiscordRestApiClient.cs

@@ -897,7 +897,7 @@ namespace Discord.API
         }
 
         //Guild Invites
-        public async Task<Invite> GetInviteAsync(string inviteId, RequestOptions options = null)
+        public async Task<Invite> GetInviteAsync(string inviteId, GetInviteParams args, RequestOptions options = null)
         {
             Preconditions.NotNullOrEmpty(inviteId, nameof(inviteId));
             options = RequestOptions.CreateOrClone(options);
@@ -912,7 +912,7 @@ namespace Discord.API
 
             try
             {
-                return await SendAsync<Invite>("GET", () => $"invites/{inviteId}", new BucketIds(), options: options).ConfigureAwait(false);
+                return await SendJsonAsync<Invite>("GET", () => $"invites/{inviteId}", args, new BucketIds(), options: options).ConfigureAwait(false);
             }
             catch (HttpException ex) when (ex.HttpCode == HttpStatusCode.NotFound) { return null; }
         }

src/Discord.Net.Rest/DiscordRestClient.cs

@@ -56,8 +56,8 @@ namespace Discord.Rest
             => ClientHelper.GetConnectionsAsync(this, options);
 
         /// <inheritdoc />
-        public Task<RestInvite> GetInviteAsync(string inviteId, RequestOptions options = null)
-            => ClientHelper.GetInviteAsync(this, inviteId, options);
+        public Task<RestInvite> GetInviteAsync(string inviteId, bool withCount = false, RequestOptions options = null)
+            => ClientHelper.GetInviteAsync(this, inviteId, withCount, options);
 
         /// <inheritdoc />
         public Task<RestGuild> GetGuildAsync(ulong id, RequestOptions options = null)
@@ -131,8 +131,8 @@ namespace Discord.Rest
         async Task<IReadOnlyCollection<IConnection>> IDiscordClient.GetConnectionsAsync(RequestOptions options)
             => await GetConnectionsAsync(options).ConfigureAwait(false);
 
-        async Task<IInvite> IDiscordClient.GetInviteAsync(string inviteId, RequestOptions options)
-            => await GetInviteAsync(inviteId, options).ConfigureAwait(false);
+        async Task<IInvite> IDiscordClient.GetInviteAsync(string inviteId, bool withCount, RequestOptions options)
+            => await GetInviteAsync(inviteId, withCount, options).ConfigureAwait(false);
 
         async Task<IGuild> IDiscordClient.GetGuildAsync(ulong id, CacheMode mode, RequestOptions options)
         {

src/Discord.Net.Rest/Entities/Invites/RestInvite.cs

@@ -1,6 +1,7 @@
-using System;
+using System;
 using System.Diagnostics;
 using System.Threading.Tasks;
+using Discord.API.Rest;
 using Model = Discord.API.Invite;
 
 namespace Discord.Rest
@@ -10,6 +11,8 @@ namespace Discord.Rest
     {
         public string ChannelName { get; private set; }
         public string GuildName { get; private set; }
+        public int? PresenceCount { get; private set; }
+        public int? MemberCount { get; private set; }
         public ulong ChannelId { get; private set; }
         public ulong GuildId { get; private set; }
         internal IChannel Channel { get; private set; }
@@ -36,11 +39,16 @@ namespace Discord.Rest
             ChannelId = model.Channel.Id;
             GuildName = model.Guild.Name;
             ChannelName = model.Channel.Name;
+            MemberCount = model.MemberCount.IsSpecified ? model.MemberCount.Value : null;
+            PresenceCount = model.PresenceCount.IsSpecified ? model.PresenceCount.Value : null;
         }
         
         public async Task UpdateAsync(RequestOptions options = null)
         {
-            var model = await Discord.ApiClient.GetInviteAsync(Code, options).ConfigureAwait(false);
+            var args = new GetInviteParams();
+            if (MemberCount != null || PresenceCount != null)
+                args.WithCounts = true;
+            var model = await Discord.ApiClient.GetInviteAsync(Code, args, options).ConfigureAwait(false);
             Update(model);
         }
         public Task DeleteAsync(RequestOptions options = null)