Add RTCRegion to voice channels (#2002)

* Add RTCRegion to voice channels

* Update MockedGroupChannel.cs

src/Discord.Net.Core/Entities/Channels/IAudioChannel.cs

@@ -9,6 +9,14 @@ namespace Discord
     /// </summary>
     public interface IAudioChannel : IChannel
     {
+        /// <summary>
+        ///     Gets the RTC region for this audio channel.
+        /// </summary>
+        /// <remarks>
+        ///     This property can be <see langword="null"/>.
+        /// </remarks>
+        string RTCRegion { get; }
+
         /// <summary>
         ///     Connects to this audio channel.
         /// </summary>

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

@@ -40,6 +40,8 @@ namespace Discord.API
         public Optional<int> Bitrate { get; set; }
         [JsonProperty("user_limit")]
         public Optional<int> UserLimit { get; set; }
+        [JsonProperty("rtc_region")]
+        public Optional<string> RTCRegion { get; set; }
 
         //PrivateChannel
         [JsonProperty("recipients")]

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

@@ -22,6 +22,8 @@ namespace Discord.Rest
 
         /// <inheritdoc />
         public string Name { get; private set; }
+        /// <inheritdoc/>
+        public string RTCRegion { get; private set; }
 
         public IReadOnlyCollection<RestGroupUser> Users => _users.ToReadOnlyCollection();
         public IReadOnlyCollection<RestGroupUser> Recipients
@@ -46,6 +48,8 @@ namespace Discord.Rest
 
             if (model.Recipients.IsSpecified)
                 UpdateUsers(model.Recipients.Value);
+
+            RTCRegion = model.RTCRegion.GetValueOrDefault(null);
         }
         internal void UpdateUsers(API.User[] models)
         {

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

@@ -21,6 +21,8 @@ namespace Discord.Rest
         public int? UserLimit { get; private set; }
         /// <inheritdoc />
         public ulong? CategoryId { get; private set; }
+        /// <inheritdoc/>
+        public string RTCRegion { get; private set; }
 
         /// <inheritdoc />
         public string Mention => MentionUtils.MentionChannel(Id);
@@ -46,6 +48,8 @@ namespace Discord.Rest
 
             if(model.UserLimit.IsSpecified)
                 UserLimit = model.UserLimit.Value != 0 ? model.UserLimit.Value : (int?)null;
+
+            RTCRegion = model.RTCRegion.GetValueOrDefault(null);
         }
 
         /// <inheritdoc />

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

@@ -30,6 +30,9 @@ namespace Discord.WebSocket
         /// <inheritdoc />
         public string Name { get; private set; }
 
+        /// <inheritdoc/>
+        public string RTCRegion { get; private set; }
+
         /// <inheritdoc />
         public IReadOnlyCollection<SocketMessage> CachedMessages => _messages?.Messages ?? ImmutableArray.Create<SocketMessage>();
 
@@ -67,6 +70,8 @@ namespace Discord.WebSocket
 
             if (model.Recipients.IsSpecified)
                 UpdateUsers(state, model.Recipients.Value);
+
+            RTCRegion = model.RTCRegion.GetValueOrDefault(null);
         }
         private void UpdateUsers(ClientState state, UserModel[] models)
         {

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

@@ -21,6 +21,8 @@ namespace Discord.WebSocket
         public int Bitrate { get; private set; }
         /// <inheritdoc />
         public int? UserLimit { get; private set; }
+        /// <inheritdoc/>
+        public string RTCRegion { get; private set; }
 
         /// <inheritdoc />
         public ulong? CategoryId { get; private set; }
@@ -66,6 +68,7 @@ namespace Discord.WebSocket
             CategoryId = model.CategoryId;
             Bitrate = model.Bitrate.Value;
             UserLimit = model.UserLimit.Value != 0 ? model.UserLimit.Value : (int?)null;
+            RTCRegion = model.RTCRegion.GetValueOrDefault(null);
         }
 
         /// <inheritdoc />

test/Discord.Net.Tests.Unit/MockedEntities/MockedGroupChannel.cs

@@ -16,6 +16,8 @@ namespace Discord
 
         public ulong Id => throw new NotImplementedException();
 
+        public string RTCRegion => throw new NotImplementedException();
+
         public Task<IAudioClient> ConnectAsync(bool selfDeaf = false, bool selfMute = false, bool external = false)
         {
             throw new NotImplementedException();

test/Discord.Net.Tests.Unit/MockedEntities/MockedVoiceChannel.cs

@@ -29,6 +29,8 @@ namespace Discord
         public DateTimeOffset CreatedAt => throw new NotImplementedException();
         public ulong Id => throw new NotImplementedException();
 
+        public string RTCRegion => throw new NotImplementedException();
+
         public Task AddPermissionOverwriteAsync(IRole role, OverwritePermissions permissions, RequestOptions options = null)
         {
             throw new NotImplementedException();