refactor: api_types/core/model/ui/boxes: Clarify draft types & naming.

Previously a draft was a Message, which is a much more complex data
structure received from the server with differently-named fields. The
draft system only requires the data which is subsequently sent via
the send_message API call, so a simpler API-specific set of data
structures are created and used for drafts named ~ Composition.

Other than typing, the new data structures allow space to define where
we wish to move to use newer API forms (ids vs strings) in future. An
extra 'stream_id' field is present in StreamComposition, not present in
the API, until we migrate to use IDs.

To emphasize the message/draft distinction and migration, variable names
are also updated to match.

zulipterminal/api_types.py

@@ -6,6 +6,23 @@
 EditPropagateMode = Literal['change_one', 'change_all', 'change_later']
 
 
+class PrivateComposition(TypedDict):
+    type: Literal['private']
+    content: str
+    to: List[str]  # emails  # TODO: Migrate to using List[int] (user ids)
+
+
+class StreamComposition(TypedDict):
+    type: Literal['stream']
+    content: str
+    to: str  # stream name  # TODO: Migrate to using int (stream id)
+    subject: str  # TODO: Migrate to using topic
+    stream_id: int  # FIXME: Not type of API; use until migrate to stream id
+
+
+Composition = Union[PrivateComposition, StreamComposition]
+
+
 class Message(TypedDict, total=False):
     id: int
     sender_id: int

zulipterminal/core.py

@@ -12,7 +12,7 @@
 import zulip
 from typing_extensions import Literal
 
-from zulipterminal.api_types import Message
+from zulipterminal.api_types import Composition, Message
 from zulipterminal.config.themes import ThemeSpec
 from zulipterminal.helper import asynch
 from zulipterminal.model import Model
@@ -262,10 +262,10 @@ def search_messages(self, text: str) -> None:
         if 0 <= focus_position < len(w_list):
             self.view.message_view.set_focus(focus_position)
 
-    def save_draft_confirmation_popup(self, message: Message) -> None:
+    def save_draft_confirmation_popup(self, draft: Composition) -> None:
         question = urwid.Text('Save this message as a draft?'
                               ' (This will overwrite the existing draft.)')
-        save_draft = partial(self.model.save_draft, message)
+        save_draft = partial(self.model.save_draft, draft)
         self.loop.widget = PopUpConfirmationView(self, question, save_draft)
 
     def stream_muting_confirmation_popup(self, button: Any) -> None:

zulipterminal/model.py

@@ -24,7 +24,7 @@
 from typing_extensions import Literal
 
 from zulipterminal import unicode_emojis
-from zulipterminal.api_types import EditPropagateMode, Event
+from zulipterminal.api_types import Composition, EditPropagateMode, Event
 from zulipterminal.config.keys import primary_key_for_command
 from zulipterminal.helper import (
     Message,
@@ -127,7 +127,7 @@ def __init__(self, controller: Any) -> None:
 
         self.unread_counts = classify_unread_counts(self)
 
-        self._draft: Optional[Message] = None
+        self._draft: Optional[Composition] = None
         unicode_emoji_data = unicode_emojis.EMOJI_DATA
         for name, data in unicode_emoji_data.items():
             data['type'] = 'unicode_emoji'
@@ -333,11 +333,11 @@ def react_to_message(self,
             response = self.client.add_reaction(reaction_to_toggle_spec)
         display_error_if_present(response, self.controller)
 
-    def session_draft_message(self) -> Optional[Message]:
+    def session_draft_message(self) -> Optional[Composition]:
         return deepcopy(self._draft)
 
-    def save_draft(self, message: Message) -> None:
-        self._draft = deepcopy(message)
+    def save_draft(self, draft: Composition) -> None:
+        self._draft = deepcopy(draft)
         self.controller.view.set_footer_text("Saved message as draft", 3)
 
     @asynch

zulipterminal/ui.py

@@ -224,12 +224,12 @@ def keypress(self, size: Tuple[int, int], key: str) -> Optional[str]:
             if saved_draft:
                 if saved_draft['type'] == 'stream':
                     self.write_box.stream_box_view(
-                        caption=saved_draft['display_recipient'],
+                        caption=saved_draft['to'],
                         title=saved_draft['subject'],
                         stream_id=saved_draft['stream_id'],
                     )
                 elif saved_draft['type'] == 'private':
-                    email_list = saved_draft['display_recipient']
+                    email_list = saved_draft['to']
                     recipient_user_ids = [
                         self.model.user_dict[email.strip()]['user_id']
                         for email in email_list

zulipterminal/ui_tools/boxes.py

@@ -15,6 +15,11 @@
 from tzlocal import get_localzone
 from urwid_readline import ReadlineEdit
 
+from zulipterminal.api_types import (
+    Composition,
+    PrivateComposition,
+    StreamComposition,
+)
 from zulipterminal.config.keys import (
     is_command_key,
     keys_for_command,
@@ -543,24 +548,26 @@ def keypress(self, size: urwid_Size, key: str) -> Optional[str]:
             if not self.msg_edit_id:
                 if self.to_write_box:
                     self.update_recipient_emails(self.to_write_box)
-                    message = Message(
-                            display_recipient=self.recipient_emails,
-                            content=self.msg_write_box.edit_text,
-                            type='private',
+                    this_draft: Composition = PrivateComposition(
+                        type="private",
+                        to=self.recipient_emails,
+                        content=self.msg_write_box.edit_text,
                     )
                 elif self.stream_id:
-                    message = Message(
-                        display_recipient=self.stream_write_box.edit_text,
+                    this_draft = StreamComposition(
+                        type="stream",
+                        to=self.stream_write_box.edit_text,
                         content=self.msg_write_box.edit_text,
                         subject=self.title_write_box.edit_text,
-                        stream_id=self.stream_id,
-                        type='stream',
+                        stream_id=self.stream_id,  # FIXME Migrate to ids
                     )
                 saved_draft = self.model.session_draft_message()
                 if not saved_draft:
-                    self.model.save_draft(message)
-                elif message != saved_draft:
-                    self.view.controller.save_draft_confirmation_popup(message)
+                    self.model.save_draft(this_draft)
+                elif this_draft != saved_draft:
+                    self.view.controller.save_draft_confirmation_popup(
+                        this_draft,
+                    )
         elif is_command_key('CYCLE_COMPOSE_FOCUS', key):
             if len(self.contents) == 0:
                 return key