Resolved #546: Initial implementation of "Create a service to send emails in background jobs"

framework/src/Volo.Abp.BackgroundJobs.Abstractions/Volo/Abp/BackgroundJobs/BackgroundJobOptions.cs

@@ -55,6 +55,11 @@ namespace Volo.Abp.BackgroundJobs
             return _jobConfigurationsByArgsType.Values.ToImmutableList();
         }
 
+        public void AddJob<TJob>()
+        {
+            AddJob(typeof(TJob));
+        }
+
         public void AddJob(Type jobType)
         {
             AddJob(new BackgroundJobConfiguration(jobType));

framework/src/Volo.Abp.Emailing/Volo.Abp.Emailing.csproj

@@ -19,6 +19,7 @@
   </ItemGroup>
 
   <ItemGroup>
+    <ProjectReference Include="..\Volo.Abp.BackgroundJobs.Abstractions\Volo.Abp.BackgroundJobs.Abstractions.csproj" />
     <ProjectReference Include="..\Volo.Abp.Localization\Volo.Abp.Localization.csproj" />
     <ProjectReference Include="..\Volo.Abp.Settings\Volo.Abp.Settings.csproj" />
     <ProjectReference Include="..\Volo.Abp.VirtualFileSystem\Volo.Abp.VirtualFileSystem.csproj" />

framework/src/Volo.Abp.Emailing/Volo/Abp/Emailing/AbpEmailingModule.cs

@@ -1,4 +1,5 @@
 using Microsoft.Extensions.DependencyInjection;
+using Volo.Abp.BackgroundJobs;
 using Volo.Abp.Emailing.Templates;
 using Volo.Abp.Emailing.Templates.Virtual;
 using Volo.Abp.Localization;
@@ -27,6 +28,11 @@ namespace Volo.Abp.Emailing
                 options.FileSets.AddEmbedded<AbpEmailingModule>();
             });
 
+            Configure<BackgroundJobOptions>(options =>
+            {
+                options.AddJob<BackgroundEmailSendingJob>();
+            });
+
             context.Services.Configure<EmailTemplateOptions>(options =>
             {
                 options.Templates

framework/src/Volo.Abp.Emailing/Volo/Abp/Emailing/BackgroundEmailSendingJob.cs

@@ -0,0 +1,19 @@
+using Volo.Abp.BackgroundJobs;
+
+namespace Volo.Abp.Emailing
+{
+    public class BackgroundEmailSendingJob : BackgroundJob<BackgroundEmailSendingJobArgs>
+    {
+        protected IEmailSender EmailSender { get; }
+
+        public BackgroundEmailSendingJob(IEmailSender emailSender)
+        {
+            EmailSender = emailSender;
+        }
+
+        public override void Execute(BackgroundEmailSendingJobArgs args)
+        {
+            EmailSender.Send(args.To, args.Subject, args.Body, args.IsBodyHtml);
+        }
+    }
+}

framework/src/Volo.Abp.Emailing/Volo/Abp/Emailing/BackgroundEmailSendingJobArgs.cs

@@ -0,0 +1,21 @@
+using System;
+
+namespace Volo.Abp.Emailing
+{
+    [Serializable]
+    public class BackgroundEmailSendingJobArgs
+    {
+        public string To { get; set; }
+
+        public string Subject { get; set; }
+
+        public string Body { get; set; }
+        
+        /// <summary>
+        /// Default: true.
+        /// </summary>
+        public bool IsBodyHtml { get; set; } = true;
+
+        //TODO: Add other properties and attachments
+    }
+}

framework/src/Volo.Abp.Emailing/Volo/Abp/Emailing/EmailSenderBase.cs

@@ -2,6 +2,7 @@ using System;
 using System.Net.Mail;
 using System.Text;
 using System.Threading.Tasks;
+using Volo.Abp.BackgroundJobs;
 
 namespace Volo.Abp.Emailing
 {
@@ -10,15 +11,17 @@ namespace Volo.Abp.Emailing
     /// </summary>
     public abstract class EmailSenderBase : IEmailSender
     {
-        public IEmailSenderConfiguration Configuration { get; }
+        protected IEmailSenderConfiguration Configuration { get; }
+
+        protected IBackgroundJobManager BackgroundJobManager { get; }
 
         /// <summary>
         /// Constructor.
         /// </summary>
-        /// <param name="configuration">Configuration</param>
+        protected EmailSenderBase(IEmailSenderConfiguration configuration, IBackgroundJobManager backgroundJobManager)
-        protected EmailSenderBase(IEmailSenderConfiguration configuration)
         {
             Configuration = configuration;
+            BackgroundJobManager = backgroundJobManager;
         }
 
         public virtual async Task SendAsync(string to, string subject, string body, bool isBodyHtml = true)
@@ -63,6 +66,19 @@ namespace Volo.Abp.Emailing
             await SendEmailAsync(mail);
         }
 
+        public virtual async Task QueueAsync(string to, string subject, string body, bool isBodyHtml = true)
+        {
+            await BackgroundJobManager.EnqueueAsync(
+                new BackgroundEmailSendingJobArgs
+                {
+                    To = to,
+                    Subject = subject,
+                    Body = body,
+                    IsBodyHtml = isBodyHtml
+                }
+            );
+        }
+
         public virtual void Send(MailMessage mail, bool normalize = true)
         {
             if (normalize)

framework/src/Volo.Abp.Emailing/Volo/Abp/Emailing/IEmailSender.cs

@@ -47,5 +47,12 @@ namespace Volo.Abp.Emailing
         /// If true, it sets sender address/name if it's not set before and makes mail encoding UTF-8. 
         /// </param>
         Task SendAsync(MailMessage mail, bool normalize = true);
+
+        /// <summary>
+        /// Adds an email to queue to send via background jobs.
+        /// </summary>
+        Task QueueAsync(string to, string subject, string body, bool isBodyHtml = true);
+
+        //TODO: Add other Queue methods too. Problem: MailMessage is not serializable so can not be used in background jobs.
     }
 }