remove redundant state from smtp

src/job.rs

@@ -203,8 +203,8 @@ impl Job {
                     match task::block_on(smtp.send(context, recipients_list, body, self.job_id)) {
                         Err(crate::smtp::send::Error::SendError(err)) => {
                             // Remote error, retry later.
-                            smtp.disconnect();
                             info!(context, "SMTP failed to send: {}", err);
+                            smtp.disconnect();
                             self.try_again_later(TryAgain::AtOnce, Some(err.to_string()));
                         }
                         Err(crate::smtp::send::Error::EnvelopeError(err)) => {

src/smtp/mod.rs

@@ -37,7 +37,6 @@ pub type Result<T> = std::result::Result<T, Error>;
 pub struct Smtp {
     #[debug_stub(some = "SmtpTransport")]
     transport: Option<async_smtp::smtp::SmtpTransport>,
-    transport_connected: bool,
     /// Email address we are sending from.
     from: Option<EmailAddress>,
 }
@@ -50,16 +49,12 @@ impl Smtp {
 
     /// Disconnect the SMTP transport and drop it entirely.
     pub fn disconnect(&mut self) {
-        if self.transport.is_none() || !self.transport_connected {
+        if let Some(ref mut transport) = self.transport.take() {
-            return;
+            transport.close();
         }
-
-        let mut transport = self.transport.take().unwrap();
-        transport.close();
-        self.transport_connected = false;
     }
 
-    /// Check if a connection already exists.
+    /// check whether we are connected
     pub fn is_connected(&self) -> bool {
         self.transport.is_some()
     }
@@ -143,7 +138,6 @@ impl Smtp {
         task::block_on(trans.connect()).map_err(Error::ConnectionFailure)?;
 
         self.transport = Some(trans);
-        self.transport_connected = true;
         context.call_cb(Event::SmtpConnected(format!(
             "SMTP-LOGIN as {} ok",
             lp.send_user,

src/smtp/send.rs

@@ -36,22 +36,21 @@ impl Smtp {
             .collect::<Vec<String>>()
             .join(",");
 
+        let envelope =
+            Envelope::new(self.from.clone(), recipients).map_err(Error::EnvelopeError)?;
+        let mail = SendableEmail::new(
+            envelope,
+            format!("{}", job_id), // only used for internal logging
+            message,
+        );
         if let Some(ref mut transport) = self.transport {
-            let envelope =
-                Envelope::new(self.from.clone(), recipients).map_err(Error::EnvelopeError)?;
-            let mail = SendableEmail::new(
-                envelope,
-                format!("{}", job_id), // only used for internal logging
-                message,
-            );
-
             transport.send(mail).await.map_err(Error::SendError)?;
 
             context.call_cb(Event::SmtpMessageSent(format!(
                 "Message len={} was smtp-sent to {}",
                 message_len, recipients_display
             )));
-            self.transport_connected = true;
+
             Ok(())
         } else {
             warn!(