1 files changed, 132 insertions, 0 deletions
diff --git a/SendGrid/SendGridMail/Transport/SMTP.cs b/SendGrid/SendGridMail/Transport/SMTP.cs
new file mode 100755
index 0000000..606afcd
--- /dev/null
+++ b/SendGrid/SendGridMail/Transport/SMTP.cs
@@ -0,0 +1,132 @@
+using System;
+using System.Net;
+using System.Net.Mail;
+
+namespace SendGridMail.Transport
+{
+    /// <summary>
+    /// Transport class for delivering messages via SMTP
+    /// </summary>
+    public class SMTP : ITransport
+    {
+        /// <summary>
+        /// SendGrid's host name
+        /// </summary>
+        public const String SmtpServer = "smtp.sendgrid.net";
+
+        /// <summary>
+        /// Port for Simple Mail Transfer Protocol
+        /// </summary>
+        public const Int32 Port = 25;
+
+        /// <summary>
+        /// Port for Secure SMTP
+        /// </summary>
+        public const Int32 SslPort = 465;
+
+        /// <summary>
+        /// Port for TLS (currently not supported)
+        /// </summary>
+        public const Int32 TlsPort = 571;
+
+        /// <summary>
+        /// Client used to deliver SMTP message
+        /// </summary>
+        private readonly ISmtpClient _client;
+
+        /// <summary>
+        /// Transport created to deliver messages to SendGrid using SMTP
+        /// </summary>
+        /// <param name="client">SMTP client we are wrapping</param>
+        /// <param name="credentials">Sendgrid user credentials</param>
+        /// <param name="host">MTA recieving this message.  By default, sent through SendGrid.</param>
+        /// <param name="port">SMTP port 25 is the default.  Port 465 can be used for Secure SMTP.</param>
+        private SMTP(ISmtpClient client, NetworkCredential credentials, string host = SmtpServer, int port = Port)
+        {
+            _client = client;
+            switch (port)
+            {
+                case Port:
+                    break;
+                case SslPort:
+                    _client.EnableSsl = true;
+                    break;
+                case TlsPort:
+                    throw new NotSupportedException("TLS not supported");
+            }
+        }
+
+        /// <summary>
+        /// Deliver an email using SMTP protocol
+        /// </summary>
+        /// <param name="message"></param>
+        public void Deliver(ISendGrid message)
+        {
+            var mime = message.CreateMimeMessage();
+            _client.Send(mime);
+        }
+
+        /// <summary>
+        /// Transport created to deliver messages to SendGrid using SMTP
+        /// </summary>
+        /// <param name="credentials">Sendgrid user credentials</param>
+        /// <param name="host">MTA recieving this message.  By default, sent through SendGrid.</param>
+        /// <param name="port">SMTP port 25 is the default.  Port 465 can be used for Secure SMTP.</param>
+        public static SMTP GenerateInstance(NetworkCredential credentials, String host = SmtpServer, Int32 port = Port)
+        {
+            var client = new SmtpWrapper(host, port, credentials, SmtpDeliveryMethod.Network);
+            return new SMTP(client, credentials, host, port);
+        }
+
+        /// <summary>
+        /// For Unit Testing Only!
+        /// </summary>
+        /// <param name="client"></param>
+        /// <param name="credentials"></param>
+        /// <param name="host"></param>
+        /// <param name="port"></param>
+        /// <returns></returns>
+        internal static SMTP GenerateInstance(ISmtpClient client, NetworkCredential credentials, String host = SmtpServer, Int32 port = Port)
+        {
+            return new SMTP(client, credentials, host, port);
+        }
+
+        /// <summary>
+        /// Interface to allow testing
+        /// </summary>
+        internal interface ISmtpClient
+        {
+            bool EnableSsl { get; set; }
+            void Send(MailMessage mime);
+        }
+
+        /// <summary>
+        /// Implementation of SmtpClient wrapper, separated to allow dependency injection
+        /// </summary>
+        internal class SmtpWrapper : ISmtpClient
+        {
+            private readonly SmtpClient _client;
+            public bool EnableSsl
+            {
+                get
+                {
+                    return _client.EnableSsl;
+                }
+                set
+                {
+                    _client.EnableSsl = value;
+                }
+            }
+
+            public SmtpWrapper(String host, Int32 port, NetworkCredential credentials, SmtpDeliveryMethod deliveryMethod)
+            {
+                _client = new SmtpClient(host, port) { Credentials = credentials, DeliveryMethod = deliveryMethod };
+            }
+
+            public void Send(MailMessage mime)
+            {
+                _client.Send(mime);
+            }
+        }
+    }
+}