fix #1077 for unknown senders in a group chat (such as mailer daemons): don't recreate member list and show a special stockstring-ed message advising to hit "more info".

This is the first experiment towards using structs to define the API.
It adds it as a new method on the existing Chat struct.

The types in this struct could improve as well as many other things.
But this is a straight forward translation of the existing json! macro
into a struct.

CHANGELOG.md

@@ -1,5 +1,13 @@
 # Changelog 
 
+## 1.0.0-beta.20
+
+- #1074 fix OAUTH2/gmail
+- #1072 fix group members not appearing in contact list
+- #1071 never block interrupt_idle (thus hopefully also not on maybe_network())
+- #1069 reduce smtp-timeout to 30 seconds
+- #1066 #1065 avoid unwrap in dehtml, make literals more readable
+
 ## 1.0.0-beta.19
 
 - #1058 timeout smtp-send if it doesn't complete in 15 minutes 

Cargo.lock

@@ -85,7 +85,7 @@ dependencies = [
 [[package]]
 name = "async-imap"
 version = "0.1.1"
-source = "git+https://github.com/async-email/async-imap?branch=dcc-stable#4f0852971c3f397c2b8a343ef1378992c02f61de"
+source = "git+https://github.com/async-email/async-imap?branch=dcc-stable#50e843113e3a67e924a8a14c477833da3ebc1b44"
 dependencies = [
  "async-attributes 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "async-native-tls 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -96,6 +96,7 @@ dependencies = [
  "futures 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "futures_codec 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "imap-proto 0.9.1 (git+https://github.com/djc/tokio-imap)",
+ "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "native-tls 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "nom 5.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "pin-utils 0.1.0-alpha.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -657,7 +658,7 @@ dependencies = [
 
 [[package]]
 name = "deltachat"
-version = "1.0.0-beta.19"
+version = "1.0.0-beta.20"
 dependencies = [
  "async-imap 0.1.1 (git+https://github.com/async-email/async-imap?branch=dcc-stable)",
  "async-native-tls 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -734,14 +735,15 @@ dependencies = [
 
 [[package]]
 name = "deltachat_ffi"
-version = "1.0.0-beta.19"
+version = "1.0.0-beta.20"
 dependencies = [
- "deltachat 1.0.0-beta.19",
+ "deltachat 1.0.0-beta.20",
  "deltachat-provider-database 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "failure 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "human-panic 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.44 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "deltachat"
-version = "1.0.0-beta.19"
+version = "1.0.0-beta.20"
 authors = ["Delta Chat Developers (ML) <delta@codespeak.net>"]
 edition = "2018"
 license = "MPL"

deltachat-ffi/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "deltachat_ffi"
-version = "1.0.0-beta.19"
+version = "1.0.0-beta.20"
 description = "Deltachat FFI"
 authors = ["Delta Chat Developers (ML) <delta@codespeak.net>"]
 edition = "2018"
@@ -21,6 +21,7 @@ libc = "0.2"
 human-panic = "1.0.1"
 num-traits = "0.2.6"
 failure = "0.1.6"
+serde_json = "1.0"
 
 [features]
 default = ["vendored", "nightly", "ringbuf"]

deltachat-ffi/src/lib.rs

@@ -10,6 +10,7 @@
 #[macro_use]
 extern crate human_panic;
 extern crate num_traits;
+extern crate serde_json;
 
 use std::collections::HashMap;
 use std::convert::TryInto;
@@ -2390,12 +2391,27 @@ pub unsafe extern "C" fn dc_chat_get_info_json(
     }
     let ffi_context = &*context;
     ffi_context
-        .with_inner(|ctx| match chat::get_info_json(ctx, chat_id) {
-            Ok(s) => s.strdup(),
-            Err(err) => {
-                error!(ctx, "get_info_json({}) returned: {}", chat_id, err);
-                return "".strdup();
-            }
+        .with_inner(|ctx| {
+            let chat = match chat::Chat::load_from_db(ctx, chat_id) {
+                Ok(chat) => chat,
+                Err(err) => {
+                    error!(ctx, "dc_get_chat_info_json() failed to load chat: {}", err);
+                    return "".strdup();
+                }
+            };
+            let info = match chat.get_info(ctx) {
+                Ok(info) => info,
+                Err(err) => {
+                    error!(
+                        ctx,
+                        "dc_get_chat_info_json() failed to get chat info: {}", err
+                    );
+                    return "".strdup();
+                }
+            };
+            serde_json::to_string(&info)
+                .unwrap_or_log_default(ctx, "dc_get_chat_info_json() failed to serialise to json")
+                .strdup()
         })
         .unwrap_or_else(|_| "".strdup())
 }

python/tests/test_account.py

@@ -1209,6 +1209,15 @@ class TestGroupStressTests:
         print("chat is", msg.chat)
         assert len(msg.chat.get_contacts()) == 4
 
+        lp.sec("ac3: checking that 'ac4' is a known contact")
+        ac3 = accounts[1]
+        msg3 = ac3.wait_next_incoming_message()
+        assert msg3.text == "hello"
+        contacts = ac3.get_contacts()
+        assert len(contacts) == 3
+        ac4_contacts = ac3.get_contacts(query=accounts[2].get_config("addr"))
+        assert len(ac4_contacts) == 1
+
         lp.sec("ac1: removing one contacts and checking things are right")
         to_remove = msg.chat.get_contacts()[-1]
         msg.chat.remove_contact(to_remove)

src/chat.rs

@@ -4,7 +4,7 @@ use std::path::{Path, PathBuf};
 
 use itertools::Itertools;
 use num_traits::FromPrimitive;
-use serde_json::json;
+use serde::{Deserialize, Serialize};
 
 use crate::blob::{BlobError, BlobObject};
 use crate::chatlist::*;
@@ -240,6 +240,30 @@ impl Chat {
         color
     }
 
+    /// Returns a struct describing the current state of the chat.
+    ///
+    /// This is somewhat experimental, even more so than the rest of
+    /// deltachat, and the data returned is still subject to change.
+    pub fn get_info(&self, context: &Context) -> Result<ChatInfo, Error> {
+        let draft = match get_draft(context, self.id)? {
+            Some(message) => message.text.unwrap_or_else(String::new),
+            _ => String::new(),
+        };
+        Ok(ChatInfo {
+            id: self.id,
+            type_: self.typ as u32,
+            name: self.name.clone(),
+            archived: self.archived,
+            param: self.param.to_string(),
+            gossiped_timestamp: self.get_gossiped_timestamp(context),
+            is_sending_locations: self.is_sending_locations,
+            color: self.get_color(context),
+            profile_image: self.get_profile_image(context).unwrap_or_else(PathBuf::new),
+            subtitle: self.get_subtitle(context),
+            draft,
+        })
+    }
+
     /// Returns true if the chat is archived.
     pub fn is_archived(&self) -> bool {
         self.archived
@@ -497,6 +521,68 @@ impl Chat {
     }
 }
 
+/// The current state of a chat.
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct ChatInfo {
+    /// The chat ID.
+    pub id: u32,
+
+    /// The type of chat as a `u32` representation of [Chattype].
+    ///
+    /// On the C API this number is one of the
+    /// `DC_CHAT_TYPE_UNDEFINED`, `DC_CHAT_TYPE_SINGLE`,
+    /// `DC_CHAT_TYPE_GROUP` or `DC_CHAT_TYPE_VERIFIED_GROUP`
+    /// constants.
+    #[serde(rename = "type")]
+    pub type_: u32,
+
+    /// The name of the chat.
+    pub name: String,
+
+    /// Whether the chat is archived.
+    pub archived: bool,
+
+    /// The "params" of the chat.
+    ///
+    /// This is the string-serialised version of [Params] currently.
+    pub param: String,
+
+    /// Something to do with gossiping and timestamps?
+    pub gossiped_timestamp: i64,
+
+    /// Whether this chat is currently sending location-stream messages.
+    pub is_sending_locations: bool,
+
+    /// Colour this chat should be represented in by the UI.
+    ///
+    /// Yes, spelling colour is hard.
+    pub color: u32,
+
+    /// The path to the profile image.
+    ///
+    /// If there is no profile image set this will be an empty string
+    /// currently.
+    pub profile_image: PathBuf,
+
+    /// Subtitle for the chat.
+    pub subtitle: String,
+
+    /// The draft message text.
+    ///
+    /// If the chat has not draft this is an empty string.
+    ///
+    /// TODO: This doesn't seem rich enough, it can not handle drafts
+    ///       which contain non-text parts.  Perhaps it should be a
+    ///       simple `has_draft` bool instead.
+    pub draft: String,
+    // ToDo:
+    // - [ ] deaddrop,
+    // - [ ] summary,
+    // - [ ] lastUpdated,
+    // - [ ] freshMessageCounter,
+    // - [ ] email
+}
+
 /// Create a normal chat or a group chat by a messages ID that comes typically
 /// from the deaddrop, DC_CHAT_ID_DEADDROP (1).
 ///
@@ -1990,54 +2076,6 @@ pub fn forward_msgs(context: &Context, msg_ids: &[MsgId], chat_id: u32) -> Resul
     Ok(())
 }
 
-pub fn get_info_json(context: &Context, chat_id: u32) -> Result<String, Error> {
-    let chat = Chat::load_from_db(context, chat_id).unwrap();
-
-    // ToDo:
-    // - [x] id
-    // - [x] type
-    // - [x] name
-    // - [x] archived
-    // - [x] color
-    // - [x] profileImage
-    // - [x] subtitle
-    // - [x] draft,
-    // - [ ] deaddrop,
-    // - [ ] summary,
-    // - [ ] lastUpdated,
-    // - [ ] freshMessageCounter,
-    // - [ ] email
-
-    let profile_image = match chat.get_profile_image(context) {
-        Some(path) => path.into_os_string().into_string().unwrap(),
-        None => "".to_string(),
-    };
-
-    let draft = match get_draft(context, chat_id) {
-        Ok(message) => match message {
-            Some(m) => m.text.unwrap_or_else(|| "".to_string()),
-            None => "".to_string(),
-        },
-        Err(_) => "".to_string(),
-    };
-
-    let s = json!({
-         "id": chat.id,
-         "type": chat.typ as u32,
-         "name": chat.name,
-         "archived": chat.archived,
-         "param": chat.param.to_string(),
-         "gossiped_timestamp": chat.get_gossiped_timestamp(context),
-         "is_sending_locations": chat.is_sending_locations,
-         "color": chat.get_color(context),
-         "profile_image": profile_image,
-         "subtitle": chat.get_subtitle(context),
-         "draft": draft
-    });
-
-    Ok(s.to_string())
-}
-
 pub fn get_chat_contact_cnt(context: &Context, chat_id: u32) -> usize {
     context
         .sql
@@ -2192,8 +2230,41 @@ pub fn add_info_msg(context: &Context, chat_id: u32, text: impl AsRef<str>) {
 mod tests {
     use super::*;
 
+    use crate::contact::Contact;
     use crate::test_utils::*;
 
+    #[test]
+    fn test_chat_info() {
+        let t = dummy_context();
+        let bob = Contact::create(&t.ctx, "bob", "bob@example.com").unwrap();
+        let chat_id = create_by_contact_id(&t.ctx, bob).unwrap();
+        let chat = Chat::load_from_db(&t.ctx, chat_id).unwrap();
+        let info = chat.get_info(&t.ctx).unwrap();
+
+        // Ensure we can serialise this.
+        println!("{}", serde_json::to_string_pretty(&info).unwrap());
+
+        let expected = r#"
+            {
+                "id": 10,
+                "type": 100,
+                "name": "bob",
+                "archived": false,
+                "param": "",
+                "gossiped_timestamp": 0,
+                "is_sending_locations": false,
+                "color": 15895624,
+                "profile_image": "",
+                "subtitle": "bob@example.com",
+                "draft": ""
+            }
+        "#;
+
+        // Ensure we can deserialise this.
+        let loaded: ChatInfo = serde_json::from_str(expected).unwrap();
+        assert_eq!(info, loaded);
+    }
+
     #[test]
     fn test_get_draft_no_draft() {
         let t = dummy_context();

src/contact.rs

@@ -114,14 +114,11 @@ impl Default for Origin {
 }
 
 impl Origin {
-    /// Contacts that are verified and known not to be spam.
-    pub fn is_verified(self) -> bool {
-        self as i32 >= 0x100
-    }
-
-    /// Contacts that are shown in the contact list.
-    pub fn include_in_contactlist(self) -> bool {
-        self as i32 >= DC_ORIGIN_MIN_CONTACT_LIST
+    /// Contacts that are known, i. e. they came in via accepted contacts or
+    /// themselves an accepted contact. Known contacts are shown in the
+    /// contact list when one creates a chat and wants to add members etc.
+    pub fn is_known(self) -> bool {
+        self >= Origin::IncomingReplyTo
     }
 }
 
@@ -401,6 +398,7 @@ impl Contact {
         {
             row_id = sql::get_rowid(context, &context.sql, "contacts", "addr", addr);
             sth_modified = Modifier::Created;
+            info!(context, "added contact id={} addr={}", row_id, addr);
         } else {
             error!(context, "Cannot add contact.");
         }
@@ -486,7 +484,7 @@ impl Contact {
                 params![
                     self_addr,
                     DC_CONTACT_ID_LAST_SPECIAL as i32,
-                    0x100,
+                    Origin::IncomingReplyTo,
                     &s3str_like_cmd,
                     &s3str_like_cmd,
                     if flag_verified_only { 0 } else { 1 },

src/dc_receive_imf.rs

@@ -61,9 +61,6 @@ pub fn dc_receive_imf(
     ensure!(mime_parser.has_headers(), "No Headers Found");
 
     // the function returns the number of created messages in the database
-    let mut incoming = true;
-    let mut incoming_origin = Origin::Unknown;
-    let mut to_id = 0u32;
     let mut chat_id = 0;
     let mut hidden = false;
 
@@ -74,8 +71,6 @@ pub fn dc_receive_imf(
     let mut created_db_entries = Vec::new();
     let mut create_event_to_send = Some(CreateEvent::MsgsChanged);
 
-    let mut to_ids = ContactIds::new();
-
     // helper method to handle early exit and memory cleanup
     let cleanup = |context: &Context,
                    create_event_to_send: &Option<CreateEvent>,
@@ -102,48 +97,31 @@ pub fn dc_receive_imf(
         sent_timestamp = mailparse::dateparse(value).unwrap_or_default();
     }
 
-    // Make sure, to_ids starts with the first To:-address (Cc: is added in the loop below pass)
-    if let Some(field) = mime_parser.get(HeaderDef::To) {
-        dc_add_or_lookup_contacts_by_address_list(
-            context,
-            &field,
-            if !incoming {
-                Origin::OutgoingTo
-            } else if incoming_origin.is_verified() {
-                Origin::IncomingTo
-            } else {
-                Origin::IncomingUnknownTo
-            },
-            &mut to_ids,
-        )?;
-    }
-
     // get From: (it can be an address list!) and check if it is known (for known From:'s we add
     // the other To:/Cc: in the 3rd pass)
     // or if From: is equal to SELF (in this case, it is any outgoing messages,
     // we do not check Return-Path any more as this is unreliable, see issue #150)
     let mut from_id = 0;
     let mut from_id_blocked = false;
+    let mut incoming = true;
+    let mut incoming_origin = Origin::Unknown;
 
     if let Some(field_from) = mime_parser.get(HeaderDef::From_) {
-        let mut from_ids = ContactIds::new();
-        dc_add_or_lookup_contacts_by_address_list(
+        let from_ids = dc_add_or_lookup_contacts_by_address_list(
             context,
             &field_from,
             Origin::IncomingUnknownFrom,
-            &mut from_ids,
         )?;
         if from_ids.len() > 1 {
             warn!(
                 context,
-                "mail has more than one address in From: {:?}", field_from
+                "mail has more than one From address, only using first: {:?}", field_from
             );
         }
         if from_ids.contains(&DC_CONTACT_ID_SELF) {
             incoming = false;
-            if to_ids.len() == 1 && to_ids.contains(&DC_CONTACT_ID_SELF) {
-                from_id = DC_CONTACT_ID_SELF;
-            }
+            from_id = DC_CONTACT_ID_SELF;
+            incoming_origin = Origin::OutgoingBcc;
         } else if !from_ids.is_empty() {
             from_id = from_ids.get_index(0).cloned().unwrap_or_default();
             incoming_origin = Contact::get_origin_by_id(context, from_id, &mut from_id_blocked)
@@ -155,6 +133,23 @@ pub fn dc_receive_imf(
         }
     }
 
+    let mut to_ids = ContactIds::new();
+    for header_def in &[HeaderDef::To, HeaderDef::Cc] {
+        if let Some(field) = mime_parser.get(header_def.clone()) {
+            to_ids.extend(&dc_add_or_lookup_contacts_by_address_list(
+                context,
+                &field,
+                if !incoming {
+                    Origin::OutgoingTo
+                } else if incoming_origin.is_known() {
+                    Origin::IncomingTo
+                } else {
+                    Origin::IncomingUnknownTo
+                },
+            )?);
+        }
+    }
+
     // Add parts
 
     let rfc724_mid = match mime_parser.get_rfc724_mid() {
@@ -177,17 +172,16 @@ pub fn dc_receive_imf(
             &mut mime_parser,
             imf_raw,
             incoming,
-            &mut incoming_origin,
+            incoming_origin,
             server_folder.as_ref(),
             server_uid,
-            &mut to_ids,
+            &to_ids,
             &rfc724_mid,
             &mut sent_timestamp,
-            &mut from_id,
+            from_id,
             from_id_blocked,
             &mut hidden,
             &mut chat_id,
-            &mut to_id,
             flags,
             &mut needs_delete_job,
             &mut insert_msg_id,
@@ -257,17 +251,16 @@ fn add_parts(
     mut mime_parser: &mut MimeParser,
     imf_raw: &[u8],
     incoming: bool,
-    incoming_origin: &mut Origin,
+    incoming_origin: Origin,
     server_folder: impl AsRef<str>,
     server_uid: u32,
-    to_ids: &mut ContactIds,
+    to_ids: &ContactIds,
     rfc724_mid: &str,
     sent_timestamp: &mut i64,
-    from_id: &mut u32,
+    from_id: u32,
     from_id_blocked: bool,
     hidden: &mut bool,
     chat_id: &mut u32,
-    to_id: &mut u32,
     flags: u32,
     needs_delete_job: &mut bool,
     insert_msg_id: &mut MsgId,
@@ -281,24 +274,7 @@ fn add_parts(
     let mut rcvd_timestamp = 0;
     let mut mime_in_reply_to = String::new();
     let mut mime_references = String::new();
-
-    // collect the rest information, CC: is added to the to-list, BCC: is ignored
-    // (we should not add BCC to groups as this would split groups. We could add them as "known contacts",
-    // however, the benefit is very small and this may leak data that is expected to be hidden)
-    if let Some(fld_cc) = mime_parser.get(HeaderDef::Cc) {
-        dc_add_or_lookup_contacts_by_address_list(
-            context,
-            fld_cc,
-            if !incoming {
-                Origin::OutgoingCc
-            } else if incoming_origin.is_verified() {
-                Origin::IncomingCc
-            } else {
-                Origin::IncomingUnknownCc
-            },
-            to_ids,
-        )?;
-    }
+    let mut incoming_origin = incoming_origin;
 
     // check, if the mail is already in our database - if so, just update the folder/uid
     // (if the mail was moved around) and finish. (we may get a mail twice eg. if it is
@@ -338,13 +314,15 @@ fn add_parts(
     // - outgoing messages introduce a chat with the first to: address if they are sent by a messenger
     // - incoming messages introduce a chat only for known contacts if they are sent by a messenger
     // (of course, the user can add other chats manually later)
+    let to_id: u32;
+
     if incoming {
         state = if 0 != flags & DC_IMAP_SEEN {
             MessageState::InSeen
         } else {
             MessageState::InFresh
         };
-        *to_id = DC_CONTACT_ID_SELF;
+        to_id = DC_CONTACT_ID_SELF;
         let mut needs_stop_ongoing_process = false;
 
         // handshake messages must be processed _before_ chats are created
@@ -354,7 +332,7 @@ fn add_parts(
             msgrmsg = 1;
             *chat_id = 0;
             allow_creation = true;
-            match handle_securejoin_handshake(context, mime_parser, *from_id) {
+            match handle_securejoin_handshake(context, mime_parser, from_id) {
                 Ok(ret) => {
                     if ret.hide_this_msg {
                         *hidden = true;
@@ -376,7 +354,7 @@ fn add_parts(
         }
 
         let (test_normal_chat_id, test_normal_chat_id_blocked) =
-            chat::lookup_by_contact_id(context, *from_id).unwrap_or_default();
+            chat::lookup_by_contact_id(context, from_id).unwrap_or_default();
 
         // get the chat_id - a chat_id here is no indicator that the chat is displayed in the normal list,
         // it might also be blocked and displayed in the deaddrop as a result
@@ -396,7 +374,7 @@ fn add_parts(
                 &mut mime_parser,
                 allow_creation,
                 create_blocked,
-                *from_id,
+                from_id,
                 to_ids,
             )?;
             *chat_id = new_chat_id;
@@ -417,7 +395,7 @@ fn add_parts(
 
         if *chat_id == 0 {
             // try to create a normal chat
-            let create_blocked = if *from_id == *to_id {
+            let create_blocked = if from_id == to_id {
                 Blocked::Not
             } else {
                 Blocked::Deaddrop
@@ -428,7 +406,7 @@ fn add_parts(
                 chat_id_blocked = test_normal_chat_id_blocked;
             } else if allow_creation {
                 let (id, bl) =
-                    chat::create_or_lookup_by_contact_id(context, *from_id, create_blocked)
+                    chat::create_or_lookup_by_contact_id(context, from_id, create_blocked)
                         .unwrap_or_default();
                 *chat_id = id;
                 chat_id_blocked = bl;
@@ -440,13 +418,13 @@ fn add_parts(
                 } else if is_reply_to_known_message(context, mime_parser) {
                     // we do not want any chat to be created implicitly.  Because of the origin-scale-up,
                     // the contact requests will pop up and this should be just fine.
-                    Contact::scaleup_origin_by_id(context, *from_id, Origin::IncomingReplyTo);
+                    Contact::scaleup_origin_by_id(context, from_id, Origin::IncomingReplyTo);
                     info!(
                         context,
                         "Message is a reply to a known message, mark sender as known.",
                     );
-                    if !incoming_origin.is_verified() {
-                        *incoming_origin = Origin::IncomingReplyTo;
+                    if !incoming_origin.is_known() {
+                        incoming_origin = Origin::IncomingReplyTo;
                     }
                 }
             }
@@ -461,7 +439,7 @@ fn add_parts(
         // to not result in a chatlist-contact-request (this would require the state FRESH)
         if Blocked::Not != chat_id_blocked
             && state == MessageState::InFresh
-            && !incoming_origin.is_verified()
+            && !incoming_origin.is_known()
             && msgrmsg == 0
             && show_emails != ShowEmails::All
         {
@@ -480,16 +458,15 @@ fn add_parts(
         // the mail is on the IMAP server, probably it is also delivered.
         // We cannot recreate other states (read, error).
         state = MessageState::OutDelivered;
-        *from_id = DC_CONTACT_ID_SELF;
+        to_id = to_ids.get_index(0).cloned().unwrap_or_default();
         if !to_ids.is_empty() {
-            *to_id = to_ids.get_index(0).cloned().unwrap_or_default();
             if *chat_id == 0 {
                 let (new_chat_id, new_chat_id_blocked) = create_or_lookup_group(
                     context,
                     &mut mime_parser,
                     allow_creation,
                     Blocked::Not,
-                    *from_id,
+                    from_id,
                     to_ids,
                 )?;
                 *chat_id = new_chat_id;
@@ -501,14 +478,13 @@ fn add_parts(
                 }
             }
             if *chat_id == 0 && allow_creation {
-                let create_blocked = if 0 != msgrmsg && !Contact::is_blocked_load(context, *to_id) {
+                let create_blocked = if 0 != msgrmsg && !Contact::is_blocked_load(context, to_id) {
                     Blocked::Not
                 } else {
                     Blocked::Deaddrop
                 };
-                let (id, bl) =
-                    chat::create_or_lookup_by_contact_id(context, *to_id, create_blocked)
-                        .unwrap_or_default();
+                let (id, bl) = chat::create_or_lookup_by_contact_id(context, to_id, create_blocked)
+                    .unwrap_or_default();
                 *chat_id = id;
                 chat_id_blocked = bl;
 
@@ -521,7 +497,7 @@ fn add_parts(
                 }
             }
         }
-        let self_sent = *from_id == DC_CONTACT_ID_SELF
+        let self_sent = from_id == DC_CONTACT_ID_SELF
             && to_ids.len() == 1
             && to_ids.contains(&DC_CONTACT_ID_SELF);
 
@@ -548,7 +524,7 @@ fn add_parts(
     calc_timestamps(
         context,
         *chat_id,
-        *from_id,
+        from_id,
         *sent_timestamp,
         0 == flags & DC_IMAP_SEEN,
         &mut sort_timestamp,
@@ -612,8 +588,8 @@ fn add_parts(
                     server_folder.as_ref(),
                     server_uid as i32,
                     *chat_id as i32,
-                    *from_id as i32,
-                    *to_id as i32,
+                    from_id as i32,
+                    to_id as i32,
                     sort_timestamp,
                     *sent_timestamp,
                     rcvd_timestamp,
@@ -901,10 +877,15 @@ fn create_or_lookup_group(
                 mime_parser.repl_msg_by_error(s);
             }
         }
-        // check if the sender is a member of the existing group -
-        // if not, we'll recreate the group list
         if !chat::is_contact_in_chat(context, chat_id, from_id as u32) {
-            recreate_member_list = true;
+            // The From-address is not part of this group.
+            // It could be a new user or a DSN from a mailer-daemon.
+            // in any case we do not want to recreate the member list
+            // but still show the message as part of the chat.
+            // After all, the sender has a reference/in-reply-to that
+            // points to this chat.
+            let s = context.stock_str(StockMessage::UnknownSenderForChat);
+            mime_parser.repl_msg_by_error(s.to_string());
         }
     }
 
@@ -1537,8 +1518,7 @@ fn dc_add_or_lookup_contacts_by_address_list(
     context: &Context,
     addr_list_raw: &str,
     origin: Origin,
-    to_ids: &mut ContactIds,
-) -> Result<()> {
+) -> Result<ContactIds> {
     let addrs = match mailparse::addrparse(addr_list_raw) {
         Ok(addrs) => addrs,
         Err(err) => {
@@ -1546,10 +1526,11 @@ fn dc_add_or_lookup_contacts_by_address_list(
         }
     };
 
+    let mut contact_ids = ContactIds::new();
     for addr in addrs.iter() {
         match addr {
             mailparse::MailAddr::Single(info) => {
-                to_ids.insert(add_or_lookup_contact_by_addr(
+                contact_ids.insert(add_or_lookup_contact_by_addr(
                     context,
                     &info.display_name,
                     &info.addr,
@@ -1558,7 +1539,7 @@ fn dc_add_or_lookup_contacts_by_address_list(
             }
             mailparse::MailAddr::Group(infos) => {
                 for info in &infos.addrs {
-                    to_ids.insert(add_or_lookup_contact_by_addr(
+                    contact_ids.insert(add_or_lookup_contact_by_addr(
                         context,
                         &info.display_name,
                         &info.addr,
@@ -1569,7 +1550,7 @@ fn dc_add_or_lookup_contacts_by_address_list(
         }
     }
 
-    Ok(())
+    Ok(contact_ids)
 }
 
 /// Add contacts to database on receiving messages.

src/mimefactory.rs

@@ -1002,6 +1002,21 @@ impl<'a, 'b> MimeFactory<'a, 'b> {
     }
 }
 
+/// Returns base64-encoded buffer `buf` split into 78-bytes long
+/// chunks separated by CRLF.
+///
+/// This line length limit is an
+/// [RFC5322 requirement](https://tools.ietf.org/html/rfc5322#section-2.1.1).
+fn wrapped_base64_encode(buf: &[u8]) -> String {
+    let base64 = base64::encode(&buf);
+    let mut chars = base64.chars();
+    (0..)
+        .map(|_| chars.by_ref().take(78).collect::<String>())
+        .take_while(|s| !s.is_empty())
+        .collect::<Vec<_>>()
+        .join("\r\n")
+}
+
 fn build_body_file(
     context: &Context,
     msg: &Message,
@@ -1062,7 +1077,7 @@ fn build_body_file(
     };
 
     let body = std::fs::read(blob.to_abs_path())?;
-    let encoded_body = base64::encode(&body);
+    let encoded_body = wrapped_base64_encode(&body);
 
     let mail = PartBuilder::new()
         .content_type(&mimetype)
@@ -1084,7 +1099,7 @@ fn build_selfavatar_file(context: &Context, path: String) -> Result<(PartBuilder
         None => mime::APPLICATION_OCTET_STREAM,
     };
     let body = std::fs::read(blob.to_abs_path())?;
-    let encoded_body = base64::encode(&body);
+    let encoded_body = wrapped_base64_encode(&body);
 
     let part = PartBuilder::new()
         .content_type(&mimetype)
@@ -1203,4 +1218,13 @@ mod tests {
             "<123@q> <456@d>".to_string()
         );
     }
+
+    #[test]
+    fn test_wrapped_base64_encode() {
+        let input = b"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
+        let output =
+            "QUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQU\r\n\
+             FBQUFBQUFBQQ==";
+        assert_eq!(wrapped_base64_encode(input), output);
+    }
 }

src/stock.rs

@@ -185,6 +185,9 @@ pub enum StockMessage {
                     Recipients don't need to install Delta Chat, visit websites or sign up anywhere - \
                     however, of course, if they like, you may point them to 👉 https://get.delta.chat"))]
     WelcomeMessage = 71,
+
+    #[strum(props(fallback = "Unknown Sender for this chat. See 'info' for more details."))]
+    UnknownSenderForChat = 72,
 }
 
 /*