[Feature] Refactor SendMessageAsync & SendFile(s)Async methods & modify webhook message attachments (#2609)

* initial commit

* resolve merge conficts

* code review suggestions

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

@@ -31,7 +31,8 @@ namespace Discord
         /// <param name="components">The message components to be included with this message. Used for interactions.</param>
         /// <param name="stickers">A collection of stickers to send with the message.</param>
         /// <param name="embeds">A array of <see cref="Embed"/>s to send with this response. Max 10.</param>
-        /// <param name="flags">A message flag to be applied to the sent message, only <see cref="MessageFlags.SuppressEmbeds"/> is permitted.</param>
+        /// <param name="flags">A message flag to be applied to the sent message, only <see cref="MessageFlags.SuppressEmbeds"/>
+        /// and <see cref="MessageFlags.SuppressNotification"/> is permitted.</param>
         /// <returns>
         ///     A task that represents an asynchronous send operation for delivering the message. The task result
         ///     contains the sent message.
@@ -72,7 +73,7 @@ namespace Discord
         /// <param name="components">The message components to be included with this message. Used for interactions.</param>
         /// <param name="stickers">A collection of stickers to send with the file.</param>
         /// <param name="embeds">A array of <see cref="Embed"/>s to send with this response. Max 10.</param>
-        /// <param name="flags">A message flag to be applied to the sent message, only <see cref="MessageFlags.SuppressEmbeds"/> is permitted.</param>
+        /// <param name="flags">A message flag to be applied to the sent message, only <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.SuppressNotification"/> is permitted.</param>
         /// <returns>
         ///     A task that represents an asynchronous send operation for delivering the message. The task result
         ///     contains the sent message.
@@ -110,7 +111,7 @@ namespace Discord
         /// <param name="components">The message components to be included with this message. Used for interactions.</param>
         /// <param name="stickers">A collection of stickers to send with the file.</param>
         /// <param name="embeds">A array of <see cref="Embed"/>s to send with this response. Max 10.</param>
-        /// <param name="flags">A message flag to be applied to the sent message, only <see cref="MessageFlags.SuppressEmbeds"/> is permitted.</param>
+        /// <param name="flags">A message flag to be applied to the sent message, only <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.SuppressNotification"/> is permitted.</param>
         /// <returns>
         ///     A task that represents an asynchronous send operation for delivering the message. The task result
         ///     contains the sent message.
@@ -140,7 +141,7 @@ namespace Discord
         /// <param name="components">The message components to be included with this message. Used for interactions.</param>
         /// <param name="stickers">A collection of stickers to send with the file.</param>
         /// <param name="embeds">A array of <see cref="Embed"/>s to send with this response. Max 10.</param>
-        /// <param name="flags">A message flag to be applied to the sent message, only <see cref="MessageFlags.SuppressEmbeds"/> is permitted.</param>
+        /// <param name="flags">A message flag to be applied to the sent message, only <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.SuppressNotification"/> is permitted.</param>
         /// <returns>
         ///     A task that represents an asynchronous send operation for delivering the message. The task result
         ///     contains the sent message.
@@ -170,7 +171,7 @@ namespace Discord
         /// <param name="components">The message components to be included with this message. Used for interactions.</param>
         /// <param name="stickers">A collection of stickers to send with the file.</param>
         /// <param name="embeds">A array of <see cref="Embed"/>s to send with this response. Max 10.</param>
-        /// <param name="flags">A message flag to be applied to the sent message, only <see cref="MessageFlags.SuppressEmbeds"/> is permitted.</param>
+        /// <param name="flags">A message flag to be applied to the sent message, only <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.SuppressNotification"/> is permitted.</param>
         /// <returns>
         ///     A task that represents an asynchronous send operation for delivering the message. The task result
         ///     contains the sent message.

src/Discord.Net.Core/Utils/Preconditions.cs

@@ -1,4 +1,6 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
 
 namespace Discord
 {
@@ -69,6 +71,50 @@ namespace Discord
 
         private static ArgumentException CreateNotEmptyException(string name, string msg)
             => new ArgumentException(message: msg ?? "Argument cannot be blank.", paramName: name);
+
+        #endregion
+
+        #region Message Validation
+
+        public static void WebhookMessageAtLeastOneOf(string text = null, MessageComponent components = null, ICollection<IEmbed> embeds = null,
+            IEnumerable<FileAttachment> attachments = null)
+        {
+            if (!string.IsNullOrEmpty(text))
+                return;
+
+            if (components != null && components.Components.Count != 0)
+                return;
+
+            if (attachments != null && attachments.Count() != 0)
+                return;
+
+            if (embeds != null && embeds.Count != 0)
+                return;
+
+            throw new ArgumentException($"At least one of 'Content', 'Embeds', 'Components' or 'Attachments' must be specified.");
+        }
+
+        public static void MessageAtLeastOneOf(string text = null, MessageComponent components = null, ICollection<IEmbed> embeds = null,
+                    ICollection<ISticker> stickers = null, IEnumerable<FileAttachment> attachments = null)
+        {
+            if (!string.IsNullOrEmpty(text))
+                return;
+
+            if (components != null && components.Components.Count != 0)
+                return;
+
+            if (stickers != null && stickers.Count != 0)
+                return;
+
+            if (attachments != null && attachments.Count() != 0)
+                return;
+
+            if (embeds != null && embeds.Count != 0)
+                return;
+
+            throw new ArgumentException($"At least one of 'Content', 'Embeds', 'Components', 'Stickers' or 'Attachments' must be specified.");
+        }
+
         #endregion
 
         #region Numerics

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

@@ -6,7 +6,7 @@ namespace Discord.API.Rest
     internal class CreateMessageParams
     {
         [JsonProperty("content")]
-        public string Content { get; }
+        public Optional<string> Content { get; set; }
 
         [JsonProperty("nonce")]
         public Optional<string> Nonce { get; set; }
@@ -31,10 +31,5 @@ namespace Discord.API.Rest
 
         [JsonProperty("flags")]
         public Optional<MessageFlags> Flags { get; set; }
-
-        public CreateMessageParams(string content)
-        {
-            Content = content;
-        }
     }
 }

src/Discord.Net.Rest/DiscordRestApiClient.cs

@@ -816,16 +816,16 @@ namespace Discord.API
                 endpoint = () => $"channels/{channelId}/messages?limit={limit}";
             return await SendAsync<IReadOnlyCollection<Message>>("GET", endpoint, ids, options: options).ConfigureAwait(false);
         }
+
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         public async Task<Message> CreateMessageAsync(ulong channelId, CreateMessageParams args, RequestOptions options = null)
         {
             Preconditions.NotNull(args, nameof(args));
             Preconditions.NotEqual(channelId, 0, nameof(channelId));
-            if ((!args.Embeds.IsSpecified || args.Embeds.Value == null || args.Embeds.Value.Length == 0) && (!args.Stickers.IsSpecified || args.Stickers.Value == null || args.Stickers.Value.Length == 0))
-                Preconditions.NotNullOrEmpty(args.Content, nameof(args.Content));
 
-            if (args.Content?.Length > DiscordConfig.MaxMessageSize)
+            if (args.Content.IsSpecified && args.Content.Value is not null)
-                throw new ArgumentException(message: $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", paramName: nameof(args.Content));
+                Preconditions.AtMost(args.Content.Value.Length, DiscordConfig.MaxMessageSize, nameof(args.Content), $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.");
+
             options = RequestOptions.CreateOrClone(options);
 
             var ids = new BucketIds(channelId: channelId);
@@ -840,13 +840,10 @@ namespace Discord.API
             if (AuthTokenType != TokenType.Webhook)
                 throw new InvalidOperationException($"This operation may only be called with a {nameof(TokenType.Webhook)} token.");
 
-            Preconditions.NotNull(args, nameof(args));
+            if (args.Embeds.IsSpecified)
-            Preconditions.NotEqual(webhookId, 0, nameof(webhookId));
+                Preconditions.AtMost(args.Embeds.Value.Length, DiscordConfig.MaxEmbedsPerMessage, nameof(args.Embeds), "A max of 10 Embeds are allowed.");
-            if (!args.Embeds.IsSpecified || args.Embeds.Value == null || args.Embeds.Value.Length == 0)
+            if (args.Content.IsSpecified && args.Content.Value is not null)
-                Preconditions.NotNullOrEmpty(args.Content, nameof(args.Content));
+                Preconditions.AtMost(args.Content.Value.Length, DiscordConfig.MaxMessageSize, nameof(args.Content), $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.");
-
-            if (args.Content.IsSpecified && args.Content.Value?.Length > DiscordConfig.MaxMessageSize)
-                throw new ArgumentException(message: $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", paramName: nameof(args.Content));
 
             options = RequestOptions.CreateOrClone(options);
 
@@ -866,15 +863,38 @@ namespace Discord.API
             Preconditions.NotEqual(messageId, 0, nameof(messageId));
 
             if (args.Embeds.IsSpecified)
-                Preconditions.AtMost(args.Embeds.Value.Length, 10, nameof(args.Embeds), "A max of 10 Embeds are allowed.");
+                Preconditions.AtMost(args.Embeds.Value.Length, DiscordConfig.MaxEmbedsPerMessage, nameof(args.Embeds), $"A max of {DiscordConfig.MaxEmbedsPerMessage} Embeds are allowed.");
-            if (args.Content.IsSpecified && args.Content.Value.Length > DiscordConfig.MaxMessageSize)
+            if (args.Content.IsSpecified && args.Content.Value is not null)
-                throw new ArgumentException(message: $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", paramName: nameof(args.Content));
+                Preconditions.AtMost(args.Content.Value.Length, DiscordConfig.MaxMessageSize, nameof(args.Content), $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.");
+
             options = RequestOptions.CreateOrClone(options);
 
             var ids = new BucketIds(webhookId: webhookId);
             await SendJsonAsync<Message>("PATCH", () => $"webhooks/{webhookId}/{AuthToken}/messages/{messageId}?{WebhookQuery(false, threadId)}", args, ids, clientBucket: ClientBucketType.SendEdit, options: options).ConfigureAwait(false);
         }
 
+        /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
+        /// <exception cref="InvalidOperationException">This operation may only be called with a <see cref="TokenType.Webhook"/> token.</exception>
+        public async Task ModifyWebhookMessageAsync(ulong webhookId, ulong messageId, UploadWebhookFileParams args, RequestOptions options = null, ulong? threadId = null)
+        {
+            if (AuthTokenType != TokenType.Webhook)
+                throw new InvalidOperationException($"This operation may only be called with a {nameof(TokenType.Webhook)} token.");
+
+            Preconditions.NotNull(args, nameof(args));
+            Preconditions.NotEqual(webhookId, 0, nameof(webhookId));
+            Preconditions.NotEqual(messageId, 0, nameof(messageId));
+
+            if (args.Embeds.IsSpecified)
+                Preconditions.AtMost(args.Embeds.Value.Length, DiscordConfig.MaxEmbedsPerMessage, nameof(args.Embeds), $"A max of {DiscordConfig.MaxEmbedsPerMessage} Embeds are allowed.");
+            if (args.Content.IsSpecified && args.Content.Value is not null)
+                Preconditions.AtMost(args.Content.Value.Length, DiscordConfig.MaxMessageSize, nameof(args.Content), $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.");
+
+            options = RequestOptions.CreateOrClone(options);
+
+            var ids = new BucketIds(webhookId: webhookId);
+            await SendMultipartAsync<Message>("PATCH", () => $"webhooks/{webhookId}/{AuthToken}/messages/{messageId}?{WebhookQuery(false, threadId)}", args.ToDictionary(), ids, clientBucket: ClientBucketType.SendEdit, options: options).ConfigureAwait(false);
+        }
+
         /// <exception cref="InvalidOperationException">This operation may only be called with a <see cref="TokenType.Webhook"/> token.</exception>
         public async Task DeleteWebhookMessageAsync(ulong webhookId, ulong messageId, RequestOptions options = null, ulong? threadId = null)
         {
@@ -897,10 +917,10 @@ namespace Discord.API
             Preconditions.NotEqual(channelId, 0, nameof(channelId));
             options = RequestOptions.CreateOrClone(options);
 
-            if (args.Content.GetValueOrDefault(null) == null)
+            if (args.Embeds.IsSpecified)
-                args.Content = "";
+                Preconditions.AtMost(args.Embeds.Value.Length, DiscordConfig.MaxEmbedsPerMessage, nameof(args.Embeds), $"A max of {DiscordConfig.MaxEmbedsPerMessage} Embeds are allowed.");
-            else if (args.Content.IsSpecified && args.Content.Value?.Length > DiscordConfig.MaxMessageSize)
+            if (args.Content.IsSpecified && args.Content.Value is not null)
-                throw new ArgumentOutOfRangeException($"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", nameof(args.Content));
+                Preconditions.AtMost(args.Content.Value.Length, DiscordConfig.MaxMessageSize, nameof(args.Content), $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.");
 
             var ids = new BucketIds(channelId: channelId);
             return await SendMultipartAsync<Message>("POST", () => $"channels/{channelId}/messages", args.ToDictionary(), ids, clientBucket: ClientBucketType.SendEdit, options: options).ConfigureAwait(false);
@@ -917,19 +937,15 @@ namespace Discord.API
             Preconditions.NotEqual(webhookId, 0, nameof(webhookId));
             options = RequestOptions.CreateOrClone(options);
 
-            if (args.Content.GetValueOrDefault(null) == null)
+            if (args.Embeds.IsSpecified)
-                args.Content = "";
+                Preconditions.AtMost(args.Embeds.Value.Length, DiscordConfig.MaxEmbedsPerMessage, nameof(args.Embeds), $"A max of {DiscordConfig.MaxEmbedsPerMessage} Embeds are allowed.");
-            else if (args.Content.IsSpecified)
+            if (args.Content.IsSpecified && args.Content.Value is not null)
-            {
+                Preconditions.AtMost(args.Content.Value.Length, DiscordConfig.MaxMessageSize, nameof(args.Content), $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.");
-                if (args.Content.Value == null)
-                    args.Content = "";
-                if (args.Content.Value?.Length > DiscordConfig.MaxMessageSize)
-                    throw new ArgumentOutOfRangeException($"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", nameof(args.Content));
-            }
 
             var ids = new BucketIds(webhookId: webhookId);
             return await SendMultipartAsync<Message>("POST", () => $"webhooks/{webhookId}/{AuthToken}?{WebhookQuery(true, threadId)}", args.ToDictionary(), ids, clientBucket: ClientBucketType.SendEdit, options: options).ConfigureAwait(false);
         }
+
         public async Task DeleteMessageAsync(ulong channelId, ulong messageId, RequestOptions options = null)
         {
             Preconditions.NotEqual(channelId, 0, nameof(channelId));
@@ -939,6 +955,7 @@ namespace Discord.API
             var ids = new BucketIds(channelId: channelId);
             await SendAsync("DELETE", () => $"channels/{channelId}/messages/{messageId}", ids, options: options).ConfigureAwait(false);
         }
+
         public async Task DeleteMessagesAsync(ulong channelId, DeleteMessagesParams args, RequestOptions options = null)
         {
             Preconditions.NotEqual(channelId, 0, nameof(channelId));
@@ -967,8 +984,12 @@ namespace Discord.API
             Preconditions.NotEqual(channelId, 0, nameof(channelId));
             Preconditions.NotEqual(messageId, 0, nameof(messageId));
             Preconditions.NotNull(args, nameof(args));
-            if (args.Content.IsSpecified && args.Content.Value?.Length > DiscordConfig.MaxMessageSize)
+
-                throw new ArgumentOutOfRangeException($"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", nameof(args.Content));
+            if (args.Embeds.IsSpecified)
+                Preconditions.AtMost(args.Embeds.Value.Length, DiscordConfig.MaxEmbedsPerMessage, nameof(args.Embeds), "A max of 10 Embeds are allowed.");
+            if (args.Content.IsSpecified && args.Content.Value is not null)
+                Preconditions.AtMost(args.Content.Value.Length, DiscordConfig.MaxMessageSize, nameof(args.Content), $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.");
+
             options = RequestOptions.CreateOrClone(options);
 
             var ids = new BucketIds(channelId: channelId);
@@ -980,8 +1001,12 @@ namespace Discord.API
             Preconditions.NotEqual(channelId, 0, nameof(channelId));
             Preconditions.NotEqual(messageId, 0, nameof(messageId));
             Preconditions.NotNull(args, nameof(args));
-            if (args.Content.IsSpecified && args.Content.Value?.Length > DiscordConfig.MaxMessageSize)
+
-                throw new ArgumentOutOfRangeException($"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", nameof(args.Content));
+            if (args.Embeds.IsSpecified)
+                Preconditions.AtMost(args.Embeds.Value.Length, DiscordConfig.MaxEmbedsPerMessage, nameof(args.Embeds), "A max of 10 Embeds are allowed.");
+            if (args.Content.IsSpecified && args.Content.Value is not null)
+                Preconditions.AtMost(args.Content.Value.Length, DiscordConfig.MaxMessageSize, nameof(args.Content), $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.");
+
             options = RequestOptions.CreateOrClone(options);
 
             var ids = new BucketIds(channelId: channelId);
@@ -1444,8 +1469,15 @@ namespace Discord.API
 
         public async Task<Message> CreateInteractionFollowupMessageAsync(CreateWebhookMessageParams args, string token, RequestOptions options = null)
         {
-            if ((!args.Embeds.IsSpecified || args.Embeds.Value == null || args.Embeds.Value.Length == 0) && !args.File.IsSpecified)
+            if ((!args.Embeds.IsSpecified || args.Embeds.Value == null || args.Embeds.Value.Length == 0)
-                Preconditions.NotNullOrEmpty(args.Content, nameof(args.Content));
+                && (!args.Content.IsSpecified || args.Content.Value is null || string.IsNullOrWhiteSpace(args.Content.Value))
+                && (!args.Components.IsSpecified || args.Components.Value is null || args.Components.Value.Length == 0))
+            {
+                throw new ArgumentException("At least one of 'Content', 'Embeds', 'File' or 'Components' must be specified.", nameof(args));
+            }
+
+            if (args.Content.IsSpecified && args.Content.Value is not null && args.Content.Value.Length > DiscordConfig.MaxMessageSize)
+                throw new ArgumentException(message: $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", paramName: nameof(args.Content));
 
             if (args.Content.IsSpecified && args.Content.Value?.Length > DiscordConfig.MaxMessageSize)
                 throw new ArgumentException(message: $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", paramName: nameof(args.Content));
@@ -1460,9 +1492,12 @@ namespace Discord.API
 
         public async Task<Message> CreateInteractionFollowupMessageAsync(UploadWebhookFileParams args, string token, RequestOptions options = null)
         {
-            if ((!args.Embeds.IsSpecified || args.Embeds.Value == null || args.Embeds.Value.Length == 0) && !args.Files.Any())
+            if ((!args.Embeds.IsSpecified || args.Embeds.Value == null || args.Embeds.Value.Length == 0)
-                Preconditions.NotNullOrEmpty(args.Content, nameof(args.Content));
+                && (!args.Content.IsSpecified || args.Content.Value is null || string.IsNullOrWhiteSpace(args.Content.Value))
-
+                && (!args.MessageComponents.IsSpecified || args.MessageComponents.Value is null || args.MessageComponents.Value.Length == 0))
+            {
+                throw new ArgumentException("At least one of 'Content', 'Embeds', 'Files' or 'Components' must be specified.", nameof(args));
+            }
             if (args.Content.IsSpecified && args.Content.Value?.Length > DiscordConfig.MaxMessageSize)
                 throw new ArgumentException(message: $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", paramName: nameof(args.Content));
 

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

@@ -281,7 +281,9 @@ namespace Discord.Rest
 
             Preconditions.AtMost(allowedMentions?.RoleIds?.Count ?? 0, 100, nameof(allowedMentions.RoleIds), "A max of 100 role Ids are allowed.");
             Preconditions.AtMost(allowedMentions?.UserIds?.Count ?? 0, 100, nameof(allowedMentions.UserIds), "A max of 100 user Ids are allowed.");
-            Preconditions.AtMost(embeds.Length, 10, nameof(embeds), "A max of 10 embeds are allowed.");
+            Preconditions.AtMost(embeds.Length, DiscordConfig.MaxEmbedsPerMessage, nameof(embeds), $"A max of {DiscordConfig.MaxEmbedsPerMessage} Embeds are allowed.");
+
+            Preconditions.MessageAtLeastOneOf(text, components, embeds, stickers);
 
             // check that user flag and user Id list are exclusive, same with role flag and role Id list
             if (allowedMentions != null && allowedMentions.AllowedTypes.HasValue)
@@ -304,12 +306,12 @@ namespace Discord.Rest
                 Preconditions.AtMost(stickers.Length, 3, nameof(stickers), "A max of 3 stickers are allowed.");
             }
 
-
+            if (flags is not MessageFlags.None and not MessageFlags.SuppressEmbeds and not MessageFlags.SuppressNotification)
-            if (flags is not MessageFlags.None and not MessageFlags.SuppressEmbeds)
                 throw new ArgumentException("The only valid MessageFlags are SuppressEmbeds and none.", nameof(flags));
 
-            var args = new CreateMessageParams(text)
+            var args = new CreateMessageParams
             {
+                Content = text,
                 IsTTS = isTTS,
                 Embeds = embeds.Any() ? embeds.Select(x => x.ToModel()).ToArray() : Optional<API.Embed[]>.Unspecified,
                 AllowedMentions = allowedMentions?.ToModel(),
@@ -346,7 +348,7 @@ namespace Discord.Rest
         /// <exception cref="NotSupportedException"><paramref name="filePath" /> is in an invalid format.</exception>
         /// <exception cref="IOException">An I/O error occurred while opening the file.</exception>
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
         public static async Task<RestUserMessage> SendFileAsync(IMessageChannel channel, BaseDiscordClient client,
             string filePath, string text, bool isTTS, Embed embed, AllowedMentions allowedMentions,
             MessageReference messageReference, MessageComponent components, ISticker[] stickers, RequestOptions options,
@@ -379,7 +381,7 @@ namespace Discord.Rest
             => SendFilesAsync(channel, client, new[] { attachment }, text, isTTS, embed, allowedMentions, messageReference,
                 components, stickers, options, embeds, flags);
 
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
         public static async Task<RestUserMessage> SendFilesAsync(IMessageChannel channel, BaseDiscordClient client,
             IEnumerable<FileAttachment> attachments, string text, bool isTTS, Embed embed, AllowedMentions allowedMentions,
             MessageReference messageReference, MessageComponent components, ISticker[] stickers, RequestOptions options,
@@ -391,7 +393,9 @@ namespace Discord.Rest
 
             Preconditions.AtMost(allowedMentions?.RoleIds?.Count ?? 0, 100, nameof(allowedMentions.RoleIds), "A max of 100 role Ids are allowed.");
             Preconditions.AtMost(allowedMentions?.UserIds?.Count ?? 0, 100, nameof(allowedMentions.UserIds), "A max of 100 user Ids are allowed.");
-            Preconditions.AtMost(embeds.Length, 10, nameof(embeds), "A max of 10 embeds are allowed.");
+            Preconditions.AtMost(embeds.Length, DiscordConfig.MaxEmbedsPerMessage, nameof(embeds), $"A max of {DiscordConfig.MaxEmbedsPerMessage} Embeds are allowed.");
+
+            Preconditions.MessageAtLeastOneOf(text, components, embeds, stickers, attachments);
 
             foreach (var attachment in attachments)
             {
@@ -424,8 +428,8 @@ namespace Discord.Rest
                 }
             }
 
-            if (flags is not MessageFlags.None and not MessageFlags.SuppressEmbeds)
+            if (flags is not MessageFlags.None and not MessageFlags.SuppressEmbeds and not MessageFlags.SuppressNotification)
-                throw new ArgumentException("The only valid MessageFlags are SuppressEmbeds and none.", nameof(flags));
+                throw new ArgumentException("The only valid MessageFlags are SuppressEmbeds, SuppressNotification and none.", nameof(flags));
 
             if (stickers != null)
             {

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

@@ -127,7 +127,7 @@ namespace Discord.Rest
         /// <exception cref="IOException">An I/O error occurred while opening the file.</exception>
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null,
+        public Task<RestUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null,
             RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -135,7 +135,7 @@ namespace Discord.Rest
             components, stickers, options, isSpoiler, embeds, flags);
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -144,7 +144,7 @@ namespace Discord.Rest
 
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -153,7 +153,7 @@ namespace Discord.Rest
 
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        public Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)

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

@@ -137,7 +137,7 @@ namespace Discord.Rest
         /// <exception cref="IOException">An I/O error occurred while opening the file.</exception>
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null,
+        public Task<RestUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null,
             RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -146,7 +146,7 @@ namespace Discord.Rest
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -155,7 +155,7 @@ namespace Discord.Rest
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -164,7 +164,7 @@ namespace Discord.Rest
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)

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

@@ -114,7 +114,7 @@ namespace Discord.Rest
 
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
         public virtual Task<RestUserMessage> SendMessageAsync(string text = null, bool isTTS = false, Embed embed = null,
             RequestOptions options = null, AllowedMentions allowedMentions = null, MessageReference messageReference = null,
             MessageComponent components = null, ISticker[] stickers = null, Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -146,8 +146,8 @@ namespace Discord.Rest
         /// <exception cref="NotSupportedException"><paramref name="filePath" /> is in an invalid format.</exception>
         /// <exception cref="IOException">An I/O error occurred while opening the file.</exception>
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
-        public virtual Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null,
+        public virtual Task<RestUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null,
             RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -156,8 +156,8 @@ namespace Discord.Rest
 
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
-        public virtual Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false,
+        public virtual Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -166,8 +166,8 @@ namespace Discord.Rest
 
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
-        public virtual Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text, bool isTTS = false,
+        public virtual Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -176,8 +176,8 @@ namespace Discord.Rest
 
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
-        public virtual Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text, bool isTTS = false,
+        public virtual Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)

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

@@ -148,7 +148,7 @@ namespace Discord.WebSocket
 
         /// <inheritdoc />
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null,
+        public Task<RestUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null,
             RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -157,7 +157,7 @@ namespace Discord.WebSocket
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -166,7 +166,7 @@ namespace Discord.WebSocket
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -175,7 +175,7 @@ namespace Discord.WebSocket
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)

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

@@ -187,7 +187,7 @@ namespace Discord.WebSocket
 
         /// <inheritdoc />
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null,
+        public Task<RestUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null,
             RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -196,7 +196,7 @@ namespace Discord.WebSocket
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -205,7 +205,7 @@ namespace Discord.WebSocket
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -214,7 +214,7 @@ namespace Discord.WebSocket
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
-        public Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text, bool isTTS = false,
+        public Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)

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

@@ -222,7 +222,7 @@ namespace Discord.WebSocket
 
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
         public virtual Task<RestUserMessage> SendMessageAsync(string text = null, bool isTTS = false, Embed embed = null,
             RequestOptions options = null, AllowedMentions allowedMentions = null, MessageReference messageReference = null,
             MessageComponent components = null, ISticker[] stickers = null, Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -230,8 +230,8 @@ namespace Discord.WebSocket
                 components, stickers, options, embeds, flags);
 
         /// <inheritdoc />
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
-        public virtual Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null,
+        public virtual Task<RestUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null,
             RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -239,8 +239,8 @@ namespace Discord.WebSocket
                 components, stickers, options, isSpoiler, embeds, flags);
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
-        public virtual Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false,
+        public virtual Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -248,8 +248,8 @@ namespace Discord.WebSocket
                 messageReference, components, stickers, options, isSpoiler, embeds, flags);
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
-        public virtual Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text, bool isTTS = false,
+        public virtual Task<RestUserMessage> SendFileAsync(FileAttachment attachment, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)
@@ -257,8 +257,8 @@ namespace Discord.WebSocket
                 messageReference, components, stickers, options, embeds, flags);
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/> and <see cref="MessageFlags.None"/>.</exception>
+        /// <exception cref="ArgumentException">The only valid <see cref="MessageFlags"/> are <see cref="MessageFlags.SuppressEmbeds"/>, <see cref="MessageFlags.SuppressNotification"/> and <see cref="MessageFlags.None"/>.</exception>
-        public virtual Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text, bool isTTS = false,
+        public virtual Task<RestUserMessage> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text = null, bool isTTS = false,
             Embed embed = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
             MessageReference messageReference = null, MessageComponent components = null, ISticker[] stickers = null,
             Embed[] embeds = null, MessageFlags flags = MessageFlags.None)

src/Discord.Net.Webhook/DiscordWebhookClient.cs

@@ -1,5 +1,6 @@
 using Discord.Logging;
 using Discord.Rest;
+
 using System;
 using System.Collections.Generic;
 using System.Globalization;
@@ -7,12 +8,19 @@ using System.IO;
 using System.Text.RegularExpressions;
 using System.Threading.Tasks;
 
-namespace Discord.Webhook
+namespace Discord.Webhook;
-{
+
-    /// <summary> A client responsible for connecting as a Webhook. </summary>
+/// <summary>
+///     A client responsible for connecting as a Webhook.
+/// </summary>
 public class DiscordWebhookClient : IDisposable
 {
-        public event Func<LogMessage, Task> Log { add { _logEvent.Add(value); } remove { _logEvent.Remove(value); } }
+    public event Func<LogMessage, Task> Log
+    {
+        add => _logEvent.Add(value);
+        remove => _logEvent.Remove(value);
+    }
+
     internal readonly AsyncEvent<Func<LogMessage, Task>> _logEvent = new AsyncEvent<Func<LogMessage, Task>>();
 
     private readonly ulong _webhookId;
@@ -22,20 +30,30 @@ namespace Discord.Webhook
     internal API.DiscordRestApiClient ApiClient { get; }
     internal LogManager LogManager { get; }
 
-        /// <summary> Creates a new Webhook Discord client. </summary>
+    /// <summary>
+    ///     Creates a new Webhook Discord client.
+    /// </summary>
     public DiscordWebhookClient(IWebhook webhook)
         : this(webhook.Id, webhook.Token, new DiscordRestConfig()) { }
-        /// <summary> Creates a new Webhook Discord client. </summary>
+
+    /// <summary>
+    ///     Creates a new Webhook Discord client.
+    /// </summary>
     public DiscordWebhookClient(ulong webhookId, string webhookToken)
         : this(webhookId, webhookToken, new DiscordRestConfig()) { }
-        /// <summary> Creates a new Webhook Discord client. </summary>
+
+    /// <summary>
+    ///     Creates a new Webhook Discord client.
+    /// </summary>
     public DiscordWebhookClient(string webhookUrl)
         : this(webhookUrl, new DiscordRestConfig()) { }
 
     // regex pattern to match webhook urls
     private static Regex WebhookUrlRegex = new Regex(@"^.*(discord|discordapp)\.com\/api\/webhooks\/([\d]+)\/([a-z0-9_-]+)$", RegexOptions.Compiled | RegexOptions.IgnoreCase | RegexOptions.CultureInvariant);
 
-        /// <summary> Creates a new Webhook Discord client. </summary>
+    /// <summary>
+    ///     Creates a new Webhook Discord client.
+    /// </summary>
     public DiscordWebhookClient(ulong webhookId, string webhookToken, DiscordRestConfig config)
         : this(config)
     {
@@ -43,7 +61,10 @@ namespace Discord.Webhook
         ApiClient.LoginAsync(TokenType.Webhook, webhookToken).GetAwaiter().GetResult();
         Webhook = WebhookClientHelper.GetWebhookAsync(this, webhookId).GetAwaiter().GetResult();
     }
-        /// <summary> Creates a new Webhook Discord client. </summary>
+    
+    /// <summary>
+    ///     Creates a new Webhook Discord client.
+    /// </summary>
     public DiscordWebhookClient(IWebhook webhook, DiscordRestConfig config)
         : this(config)
     {
@@ -84,8 +105,13 @@ namespace Discord.Webhook
     }
     private static API.DiscordRestApiClient CreateApiClient(DiscordRestConfig config)
         => new API.DiscordRestApiClient(config.RestClientProvider, DiscordRestConfig.UserAgent, useSystemClock: config.UseSystemClock, defaultRatelimitCallback: config.DefaultRatelimitCallback);
-        /// <summary> Sends a message to the channel for this webhook. </summary>
+        
-        /// <returns> Returns the ID of the created message. </returns>
+    /// <summary>
+    ///     Sends a message to the channel for this webhook.
+    /// </summary>
+    /// <returns>
+    ///     Returns the ID of the created message.
+    /// </returns>
     public Task<ulong> SendMessageAsync(string text = null, bool isTTS = false, IEnumerable<Embed> embeds = null,
         string username = null, string avatarUrl = null, RequestOptions options = null, AllowedMentions allowedMentions = null,
         MessageComponent components = null, MessageFlags flags = MessageFlags.None, ulong? threadId = null, string threadName = null)
@@ -120,16 +146,25 @@ namespace Discord.Webhook
     public Task DeleteMessageAsync(ulong messageId, RequestOptions options = null, ulong? threadId = null)
         => WebhookClientHelper.DeleteMessageAsync(this, messageId, options, threadId);
 
-        /// <summary> Sends a message to the channel for this webhook with an attachment. </summary>
+    /// <summary> 
-        /// <returns> Returns the ID of the created message. </returns>
+    ///     Sends a message to the channel for this webhook with an attachment.
+    /// </summary>
+    /// <returns> 
+    ///     Returns the ID of the created message. 
+    /// </returns>
     public Task<ulong> SendFileAsync(string filePath, string text, bool isTTS = false,
         IEnumerable<Embed> embeds = null, string username = null, string avatarUrl = null,
         RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
         MessageComponent components = null, MessageFlags flags = MessageFlags.None, ulong? threadId = null, string threadName = null)
         => WebhookClientHelper.SendFileAsync(this, filePath, text, isTTS, embeds, username, avatarUrl,
             allowedMentions, options, isSpoiler, components, flags, threadId, threadName);
-        /// <summary> Sends a message to the channel for this webhook with an attachment. </summary>
+            
-        /// <returns> Returns the ID of the created message. </returns>
+    /// <summary> 
+    ///     Sends a message to the channel for this webhook with an attachment. 
+    /// </summary>
+    /// <returns> 
+    ///     Returns the ID of the created message. 
+    /// </returns>
     public Task<ulong> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false,
         IEnumerable<Embed> embeds = null, string username = null, string avatarUrl = null,
         RequestOptions options = null, bool isSpoiler = false, AllowedMentions allowedMentions = null,
@@ -146,8 +181,12 @@ namespace Discord.Webhook
         => WebhookClientHelper.SendFileAsync(this, attachment, text, isTTS, embeds, username,
             avatarUrl, allowedMentions, components, options, flags, threadId, threadName);
 
-        /// <summary> Sends a message to the channel for this webhook with an attachment. </summary>
+    /// <summary> 
-        /// <returns> Returns the ID of the created message. </returns>
+    ///     Sends a message to the channel for this webhook with an attachment.
+    /// </summary>
+    /// <returns> 
+    ///     Returns the ID of the created message.
+    /// </returns>
     public Task<ulong> SendFilesAsync(IEnumerable<FileAttachment> attachments, string text, bool isTTS = false,
         IEnumerable<Embed> embeds = null, string username = null, string avatarUrl = null,
         RequestOptions options = null, AllowedMentions allowedMentions = null, MessageComponent components = null,
@@ -155,12 +194,15 @@ namespace Discord.Webhook
         => WebhookClientHelper.SendFilesAsync(this, attachments, text, isTTS, embeds, username, avatarUrl,
             allowedMentions, components, options, flags, threadId, threadName);
 
-
+    /// <summary> 
-        /// <summary> Modifies the properties of this webhook. </summary>
+    ///     Modifies the properties of this webhook.
+    /// </summary>
     public Task ModifyWebhookAsync(Action<WebhookProperties> func, RequestOptions options = null)
         => Webhook.ModifyAsync(func, options);
 
-        /// <summary> Deletes this webhook from Discord and disposes the client. </summary>
+    /// <summary> 
+    ///     Deletes this webhook from Discord and disposes the client.
+    /// </summary>
     public async Task DeleteWebhookAsync(RequestOptions options = null)
     {
         await Webhook.DeleteAsync(options).ConfigureAwait(false);
@@ -175,14 +217,14 @@ namespace Discord.Webhook
     internal static void ParseWebhookUrl(string webhookUrl, out ulong webhookId, out string webhookToken)
     {
         if (string.IsNullOrWhiteSpace(webhookUrl))
-                throw new ArgumentNullException(paramName: nameof(webhookUrl), message:
+            throw new ArgumentNullException(nameof(webhookUrl), "The given webhook Url cannot be null or whitespace.");
-                    "The given webhook Url cannot be null or whitespace.");
 
         // thrown when groups are not populated/valid, or when there is no match
         ArgumentException ex(string reason = null)
-                => new ArgumentException(paramName: nameof(webhookUrl), message:
+            => new ($"The given webhook Url was not in a valid format. {reason}", nameof(webhookUrl));
-                $"The given webhook Url was not in a valid format. {reason}");
+
         var match = WebhookUrlRegex.Match(webhookUrl);
+
         if (match != null)
         {
             // ensure that the first group is a ulong, set the _webhookId
@@ -198,4 +240,3 @@ namespace Discord.Webhook
             throw ex();
     }
 }
-}

src/Discord.Net.Webhook/Entities/Messages/WebhookMessageProperties.cs

@@ -26,5 +26,9 @@ namespace Discord.Webhook
         ///     Gets or sets the components that the message should display.
         /// </summary>
         public Optional<MessageComponent> Components { get; set; }
+        /// <summary>
+        ///     Gets or sets the attachments for the message.
+        /// </summary>
+        public Optional<IEnumerable<FileAttachment>> Attachments { get; set; }
     }
 }

src/Discord.Net.Webhook/WebhookClientHelper.cs

@@ -22,6 +22,7 @@ namespace Discord.Webhook
                 throw new InvalidOperationException("Could not find a webhook with the supplied credentials.");
             return RestInternalWebhook.Create(client, model);
         }
+
         public static async Task<ulong> SendMessageAsync(DiscordWebhookClient client,
             string text, bool isTTS, IEnumerable<Embed> embeds, string username, string avatarUrl,
             AllowedMentions allowedMentions, RequestOptions options, MessageComponent components, MessageFlags flags, ulong? threadId = null, string threadName = null)
@@ -33,6 +34,8 @@ namespace Discord.Webhook
                 Flags = flags
             };
 
+            Preconditions.WebhookMessageAtLeastOneOf(text, components, embeds?.ToArray());
+
             if (embeds != null)
                 args.Embeds = embeds.Select(x => x.ToModel()).ToArray();
             if (username != null)
@@ -86,6 +89,8 @@ namespace Discord.Webhook
                 }
             }
 
+            if (!args.Attachments.IsSpecified)
+            {
                 var apiArgs = new ModifyWebhookMessageParams
                 {
                     Content = args.Content.IsSpecified ? args.Content.Value : Optional.Create<string>(),
@@ -102,6 +107,25 @@ namespace Discord.Webhook
                 await client.ApiClient.ModifyWebhookMessageAsync(client.Webhook.Id, messageId, apiArgs, options, threadId)
                     .ConfigureAwait(false);
             }
+            else
+            {
+                var apiArgs = new UploadWebhookFileParams(args.Attachments.Value.ToArray())
+                {
+                    Content = args.Content.IsSpecified ? args.Content.Value : Optional.Create<string>(),
+                    Embeds =
+                        args.Embeds.IsSpecified
+                            ? args.Embeds.Value.Select(embed => embed.ToModel()).ToArray()
+                            : Optional.Create<API.Embed[]>(),
+                    AllowedMentions = args.AllowedMentions.IsSpecified
+                        ? args.AllowedMentions.Value.ToModel()
+                        : Optional.Create<API.AllowedMentions>(),
+                    MessageComponents = args.Components.IsSpecified ? args.Components.Value?.Components.Select(x => new API.ActionRowComponent(x)).ToArray() : Optional<API.ActionRowComponent[]>.Unspecified,
+                };
+
+                await client.ApiClient.ModifyWebhookMessageAsync(client.Webhook.Id, messageId, apiArgs, options, threadId)
+                    .ConfigureAwait(false);
+            }
+        }
 
         public static async Task DeleteMessageAsync(DiscordWebhookClient client, ulong messageId, RequestOptions options, ulong? threadId)
         {
@@ -136,7 +160,9 @@ namespace Discord.Webhook
 
             Preconditions.AtMost(allowedMentions?.RoleIds?.Count ?? 0, 100, nameof(allowedMentions.RoleIds), "A max of 100 role Ids are allowed.");
             Preconditions.AtMost(allowedMentions?.UserIds?.Count ?? 0, 100, nameof(allowedMentions.UserIds), "A max of 100 user Ids are allowed.");
-            Preconditions.AtMost(embeds.Count(), 10, nameof(embeds), "A max of 10 embeds are allowed.");
+            Preconditions.AtMost(embeds.Count(), DiscordConfig.MaxEmbedsPerMessage, nameof(embeds), $"A max of {DiscordConfig.MaxEmbedsPerMessage} Embeds are allowed.");
+
+            Preconditions.WebhookMessageAtLeastOneOf(text, components, embeds.ToArray(), attachments);
 
             foreach (var attachment in attachments)
             {
@@ -159,8 +185,8 @@ namespace Discord.Webhook
                 }
             }
 
-            if (flags is not MessageFlags.None and not MessageFlags.SuppressEmbeds)
+            if (flags is not MessageFlags.None and not MessageFlags.SuppressEmbeds and not MessageFlags.SuppressNotification)
-                throw new ArgumentException("The only valid MessageFlags are SuppressEmbeds and none.", nameof(flags));
+                throw new ArgumentException("The only valid MessageFlags are SuppressEmbeds, SuppressNotification and none.", nameof(flags));
 
             var args = new UploadWebhookFileParams(attachments.ToArray())
             {
@@ -178,8 +204,7 @@ namespace Discord.Webhook
             return msg.Id;
         }
 
-        public static async Task<WebhookModel> ModifyAsync(DiscordWebhookClient client,
+        public static async Task<WebhookModel> ModifyAsync(DiscordWebhookClient client, Action<WebhookProperties> func, RequestOptions options)
-            Action<WebhookProperties> func, RequestOptions options)
         {
             var args = new WebhookProperties();
             func(args);