Merge pull request #85 from huntmj01/main

Modifies GraphSender to use Upload Session

Author: DavidDeSloovere

README.md

@@ -1,3 +1,11 @@
+# Fork of NatchEurope/FluentEmail.Graph
+
+Fork of [NatchEurope/FluentEmail.Graph](https://github.com/NatchEurope/FluentEmail.Graph) that modifies the `GraphSender` to use an upload session for sending emails with attachments that are 3MB or larger. I was receiving a Microsoft Graph API error when trying to use FluentEmail.Graph to send emails with attachments over 3MB.
+
+[Microsoft Docs on using the Graph API to send large attachments](https://docs.microsoft.com/en-us/graph/outlook-large-attachments?tabs=csharp)
+
+Unfortunately, the Microsoft Graph API `Send` method does not have a `SaveSentItems` argument like the `SendMail` method does, so I had to remove the option to disable saving sent items. See [Link 1](https://docs.microsoft.com/en-us/answers/questions/337574/graph-sdk-i-want-to-send-the-saved-draft-mail-but.html), [Link 2](https://docs.microsoft.com/en-us/graph/api/message-send?view=graph-rest-1.0&tabs=http), and [Link 3](https://github.com/microsoftgraph/msgraph-sdk-dotnet/issues/743).
+
 # FluentEmail.Graph
 
 Sender for [FluentEmail](https://github.com/lukencode/FluentEmail) that uses [Microsoft Graph API](https://docs.microsoft.com/en-us/graph/api/resources/mail-api-overview?view=graph-rest-1.0).
@@ -29,7 +37,6 @@ Example config in `appsettings.json`
     "AppId": "your app id",
     "TenantId": "your tenant id",
     "Secret": "your secret here",
-    "SaveSentItems": true
   }
 }
 ```

src/FluentEmail.Graph/FluentEmailServicesBuilderExtensions.cs

@@ -21,15 +21,13 @@ public static FluentEmailServicesBuilder AddGraphSender(
             this FluentEmailServicesBuilder builder,
             string graphEmailClientId,
             string graphEmailTenantId,
-            string graphEmailSecret,
-            bool saveSentItems = false)
+            string graphEmailSecret)
         {
             var options = new GraphSenderOptions
             {
                 ClientId = graphEmailClientId,
                 TenantId = graphEmailTenantId,
                 Secret = graphEmailSecret,
-                SaveSentItems = saveSentItems,
             };
             return builder.AddGraphSender(options);
         }

src/FluentEmail.Graph/GraphSender.cs

@@ -19,17 +19,13 @@
     /// </summary>
     public class GraphSender : ISender
     {
-        private readonly bool saveSent;
-
+        private const int ThreeMb = 3145728;
         private readonly GraphServiceClient graphClient;
 
         public GraphSender(GraphSenderOptions options)
         {
-            this.saveSent = options.SaveSentItems ?? true;
-
-            ClientSecretCredential spn = new ClientSecretCredential(options.TenantId, options.ClientId, options.Secret);
-
-            this.graphClient = new (spn);
+            ClientSecretCredential spn = new(options.TenantId, options.ClientId, options.Secret);
+            this.graphClient = new(spn);
         }
 
         public SendResponse Send(IFluentEmail email, CancellationToken? token = null)
@@ -41,11 +37,9 @@ public async Task<SendResponse> SendAsync(IFluentEmail email, CancellationToken?
         {
             try
             {
-                var message = CreateMessage(email);
-                await this.graphClient.Users[email.Data.FromAddress.EmailAddress]
-                    .SendMail(message, this.saveSent)
-                    .Request()
-                    .PostAsync();
+                var message = await this.CreateMessage(email);
+
+                await this.SendMessage(email, message);
 
                 return new SendResponse
                 {
@@ -61,61 +55,68 @@ await this.graphClient.Users[email.Data.FromAddress.EmailAddress]
             }
         }
 
-        private static Message CreateMessage(IFluentEmail email)
+        private async Task<Message> CreateMessage(IFluentEmail email)
         {
-            var messageBody = new ItemBody
+            var templateBody = new ItemBody
             {
                 Content = email.Data.Body,
                 ContentType = email.Data.IsHtml ? BodyType.Html : BodyType.Text,
             };
 
-            var message = new Message();
-            message.Subject = email.Data.Subject;
-            message.Body = messageBody;
-            message.From = ConvertToRecipient(email.Data.FromAddress);
-            message.ReplyTo = CreateRecipientList(email.Data.ReplyToAddresses);
-            message.ToRecipients = CreateRecipientList(email.Data.ToAddresses);
-            message.CcRecipients = CreateRecipientList(email.Data.CcAddresses);
-            message.BccRecipients = CreateRecipientList(email.Data.BccAddresses);
+            var template = new Message
+            {
+                Subject = email.Data.Subject,
+                Body = templateBody,
+                From = ConvertToRecipient(email.Data.FromAddress),
+                ReplyTo = CreateRecipientList(email.Data.ReplyToAddresses),
+                ToRecipients = CreateRecipientList(email.Data.ToAddresses),
+                CcRecipients = CreateRecipientList(email.Data.CcAddresses),
+                BccRecipients = CreateRecipientList(email.Data.BccAddresses),
+            };
+
+            Message draft = await this.graphClient
+                .Users[email.Data.FromAddress.EmailAddress]
+                .MailFolders
+                .Drafts
+                .Messages
+                .Request()
+                .AddAsync(template);
 
             if (email.Data.Attachments != null && email.Data.Attachments.Count > 0)
             {
-                message.Attachments = new MessageAttachmentsCollectionPage();
-
-                email.Data.Attachments.ForEach(
-                    a =>
+                foreach (var a in email.Data.Attachments)
+                {
+                    if (a.Data.Length < ThreeMb)
                     {
-                        var attachment = new FileAttachment
-                        {
-                            Name = a.Filename,
-                            ContentType = a.ContentType,
-                            ContentBytes = GetAttachmentBytes(a.Data),
-                        };
-
-                        message.Attachments.Add(attachment);
-                    });
+                        await this.UploadAttachmentUnder3Mb(email, draft, a);
+                    }
+                    else
+                    {
+                        await this.UploadAttachement3MbOrOver(email, draft, a);
+                    }
+                }
             }
 
             switch (email.Data.Priority)
             {
                 case Priority.High:
-                    message.Importance = Importance.High;
+                    draft.Importance = Importance.High;
                     break;
 
                 case Priority.Normal:
-                    message.Importance = Importance.Normal;
+                    draft.Importance = Importance.Normal;
                     break;
 
                 case Priority.Low:
-                    message.Importance = Importance.Low;
+                    draft.Importance = Importance.Low;
                     break;
 
                 default:
-                    message.Importance = Importance.Normal;
+                    draft.Importance = Importance.Normal;
                     break;
             }
 
-            return message;
+            return draft;
         }
 
         private static IList<Recipient> CreateRecipientList(IEnumerable<Address> addressList)
@@ -147,11 +148,61 @@ private static Recipient ConvertToRecipient([NotNull] Address address)
             };
         }
 
+        private async Task UploadAttachmentUnder3Mb(IFluentEmail email, Message draft, Core.Models.Attachment a)
+        {
+            var attachment = new FileAttachment
+            {
+                Name = a.Filename,
+                ContentType = a.ContentType,
+                ContentBytes = GetAttachmentBytes(a.Data),
+            };
+
+            await this.graphClient
+                .Users[email.Data.FromAddress.EmailAddress]
+                .Messages[draft.Id]
+                .Attachments
+                .Request()
+                .AddAsync(attachment);
+        }
+
         private static byte[] GetAttachmentBytes(Stream stream)
         {
             using var m = new MemoryStream();
             stream.CopyTo(m);
             return m.ToArray();
         }
+
+        private async Task UploadAttachement3MbOrOver(IFluentEmail email, Message draft, Core.Models.Attachment a)
+        {
+            var attachmentItem = new AttachmentItem
+            {
+                AttachmentType = AttachmentType.File,
+                Name = a.Filename,
+                Size = a.Data.Length,
+            };
+
+            var uploadSession = await this.graphClient
+                .Users[email.Data.FromAddress.EmailAddress]
+                .Messages[draft.Id]
+                .Attachments
+                .CreateUploadSession(attachmentItem)
+                .Request()
+                .PostAsync();
+
+            int maxSliceSize = 320 * 1024;
+            var fileUploadTask = new LargeFileUploadTask<FileAttachment>(uploadSession, a.Data, maxSliceSize);
+
+            await fileUploadTask.UploadAsync();
+        }
+
+        private async Task SendMessage(IFluentEmail email, Message message)
+        {
+            await this.graphClient
+                .Users[email.Data.FromAddress.EmailAddress]
+                .Messages[message.Id]
+                .Send()
+                .Request()
+                .PostAsync();
+        }
     }
 }

src/FluentEmail.Graph/GraphSenderOptions.cs

@@ -19,10 +19,5 @@ public class GraphSenderOptions
         /// Gets or sets the secret string previously shared with AAD at application registration to prove the identity of the application (the client) requesting the tokens.
         /// </summary>
         public string Secret { get; set; }
-
-        /// <summary>
-        /// Gets or sets a value indicating whether to save the message in Sent Items. Default is <c>true</c>.
-        /// </summary>
-        public bool? SaveSentItems { get; set; }
     }
 }