fix: use correct From address when sending MDNs

deltachat-rpc-client/tests/test_multitransport.py

@@ -389,3 +389,14 @@ def test_background_fetch_no_duplicates(acf, direct_imap, dc):
 
     dc.background_fetch(300)
     assert len(messages_with_text(alice_chat, "hello")) == 1
+
+
+def test_multitransport_mdn(acf):
+    """Test sending an MDN right after configuring two transports."""
+    alice, bob = acf.get_online_accounts(2)
+    alice.add_transport_from_qr(acf.get_account_qr())
+    alice.bring_online()
+    alice.create_chat(bob)
+    bob_msg = bob.create_chat(alice).send_text("Hello!")
+    alice.wait_for_incoming_msg().mark_seen()
+    assert bob.wait_for_event(EventType.MSG_READ).msg_id == bob_msg.id

src/mimefactory.rs

@@ -447,6 +447,7 @@ pub(crate) fn render_queued_mail(
 }
 
 /// Renders queued mail with the current sending address.
+#[cfg(test)]
 pub(crate) async fn render_queued_mail_with_context(
     queued_mail: QueuedMail,
     context: &Context,
@@ -1319,13 +1320,16 @@ impl MimeFactory {
     ///
     /// Used for MDNs because they are fully rendered and sent in one go,
     /// rather than first creating a [`QueuedMail`] and sending it later.
-    pub async fn render(self, context: &Context) -> Result<RenderedEmail> {
+    pub async fn render(self, context: &Context, from_addr: &str) -> Result<RenderedEmail> {
         // Does not matter, we are not going to return the QueuedMail.
         let bcc_self = false;
+        let public_key = key::load_self_public_key(context).await?;
+        let secret_key = key::load_self_secret_key(context).await?;
 
         let (queued_mail, _side_effects) =
             Box::pin(self.into_queued_mail(context, bcc_self)).await?;
-        let rendered_mail = render_queued_mail_with_context(queued_mail, context).await?;
+        let rendered_mail =
+            render_queued_mail(queued_mail, &public_key, &secret_key, from_addr.to_string())?;
         Ok(rendered_mail)
     }
 

src/mimefactory/mimefactory_tests.rs

@@ -307,7 +307,8 @@ async fn test_mdn_create_encrypted() -> Result<()> {
     let mimefactory =
         MimeFactory::from_mdn(&bob, rcvd.from_id, rcvd.rfc724_mid.clone(), vec![]).await?;
     assert!(!mimefactory.will_be_encrypted());
-    let rendered_msg = mimefactory.render(&bob).await?;
+    let bob_addr = bob.get_primary_self_addr().await?;
+    let rendered_msg = mimefactory.render(&bob, &bob_addr).await?;
 
     assert!(!rendered_msg.message.contains("Bob Examplenet"));
     assert!(!rendered_msg.message.contains("Alice Exampleorg"));
@@ -320,7 +321,8 @@ async fn test_mdn_create_encrypted() -> Result<()> {
 
     let mimefactory = MimeFactory::from_mdn(&bob, rcvd.from_id, rcvd.rfc724_mid, vec![]).await?;
     assert!(mimefactory.will_be_encrypted());
-    let rendered_msg = mimefactory.render(&bob).await?;
+    let bob_addr = bob.get_primary_self_addr().await?;
+    let rendered_msg = mimefactory.render(&bob, &bob_addr).await?;
 
     assert!(!rendered_msg.message.contains("Bob Examplenet"));
     assert!(!rendered_msg.message.contains("Alice Exampleorg"));
@@ -363,7 +365,8 @@ async fn test_mdn_autocrypt_throttle() -> Result<()> {
         rcvd: &Message,
     ) -> Result<bool> {
         let mf = MimeFactory::from_mdn(bob, rcvd.from_id, rcvd.rfc724_mid.clone(), vec![]).await?;
-        let rendered_msg = mf.render(bob).await?;
+        let addr = bob.get_primary_self_addr().await?;
+        let rendered_msg = mf.render(bob, &addr).await?;
         let mime = MimeMessage::from_bytes(alice, rendered_msg.message.as_bytes()).await?;
         Ok(mime.autocrypt_fingerprint.is_some())
     }
@@ -644,7 +647,8 @@ async fn test_render_reply() {
     let recipients = mimefactory.recipients();
     assert_eq!(recipients, vec!["charlie@example.net"]);
 
-    let rendered_msg = mimefactory.render(t).await.unwrap();
+    let addr = t.get_primary_self_addr().await.unwrap();
+    let rendered_msg = mimefactory.render(t, &addr).await.unwrap();
 
     let mail = mailparse::parse_mail(rendered_msg.message.as_bytes()).unwrap();
     assert_eq!(

src/receive_imf/receive_imf_tests.rs

@@ -2733,7 +2733,8 @@ async fn test_read_receipts_dont_create_chats() -> Result<()> {
         vec![],
     )
     .await?;
-    let rendered_mdn = mdn_mimefactory.render(&bob).await?;
+    let bob_addr = bob.get_primary_self_addr().await?;
+    let rendered_mdn = mdn_mimefactory.render(&bob, &bob_addr).await?;
     let mdn_body = rendered_mdn.message;
 
     // Alice receives the read receipt.
@@ -2768,7 +2769,8 @@ async fn test_read_receipts_dont_unmark_bots() -> Result<()> {
         vec![],
     )
     .await?;
-    let rendered_mdn = mdn_mimefactory.render(bob).await?;
+    let bob_addr = bob.get_primary_self_addr().await?;
+    let rendered_mdn = mdn_mimefactory.render(bob, &bob_addr).await?;
     let mdn_body = rendered_mdn.message;
 
     // Alice receives the read receipt.

src/smtp.rs

@@ -218,15 +218,6 @@ pub(crate) async fn smtp_send(
 
     smtp.connectivity.set_working(context);
 
-    if let Err(err) = smtp
-        .connect_configured(context)
-        .await
-        .context("Failed to open SMTP connection")
-    {
-        smtp.last_send_error = Some(format!("{err:#}"));
-        return SendResult::Retry;
-    }
-
     let send_result = smtp.send(context, recipients, message.as_bytes()).await;
     smtp.last_send_error = send_result.as_ref().err().map(|e| e.to_string());
 
@@ -703,7 +694,12 @@ async fn send_mdn_rfc724_mid(
     } else {
         mimefactory.recipients()
     };
-    let rendered_msg = Box::pin(mimefactory.render(context)).await?;
+    let from = smtp
+        .from
+        .as_ref()
+        .context("No From address, not connected")?
+        .to_string();
+    let rendered_msg = Box::pin(mimefactory.render(context, &from)).await?;
     let body = rendered_msg.message;
 
     if context.get_config_bool(Config::BccSelf).await? {
@@ -772,6 +768,19 @@ async fn send_mdn(context: &Context, smtp: &mut Smtp) -> Result<bool> {
     };
     let (rfc724_mid, contact_id) = msg_row;
 
+    // Connect SMTP after checking that we have an MDN to send,
+    // but before increasing MDN retry counter.
+    // If we don't have an MDN, no need to connect.
+    // If we are offline and cannot connect, it is not a failure of an MDN.
+    if let Err(err) = smtp
+        .connect_configured(context)
+        .await
+        .context("SMTP connection failure while preparing to send MDNs")
+    {
+        smtp.last_send_error = Some(format!("{err:#}"));
+        return Err(err);
+    }
+
     context
         .sql
         .execute(