With this commit, most threads show an indicator when a member is typing
something. e.g.
"Mitchell Stephens is typing..."
Supported threads:
- DM
- (public & private) channels
- Livechat (Website & Backend)
Unsupported threads:
- mailboxes (e.g. 'Inbox')
- document thread (= 'Chatter')
- support channel (with `im_support` module)
Some technical details:
- This is a mix between 'start'/'stop' and 'regular notify' strategies.
- On typing text in composer: notify 'start typing' to all members of
thread.
- On clearing text in composer: notify 'stop typing' to all members of
thread.
- A member can only notify once every 2.5 seconds to the server when he
starts or stops typing something (throttled, buffered notify call).
- On receiving a message from someone that is typing: determine that he is
no longer typing.
- On non-empty and unchanged composer text for 5.0 seconds: automatically
notifies all members of thread that he is no longer typing anything.
(This is like a 'soft / cooperative sender' timeout).
- On non-receiving a typing notification of someone after 60 seconds:
determine that he is not longer typing something (This is like a
'hard / receiver assumption' timeout).
- When some types for more than 50 seconds straight: notify that he is
still typing something (again and again every 50 seconds).
- When two or more people are typing something (Multi-User channels), it
displays at most 2 typing users (ordering rule: longer typers first):
"Mitchell Stephens, Marc Brown and more are typing..."
- Timing summary:
- Usually 2.5 seconds uncertainty.
- Up to 5.0 seconds uncertainty on typer inactivity.
- Up to 60 seconds uncertainty on typer page reload / browser tab
closed / etc.
Future Improvements:
- Detect page reload or browser tab close with loose of longpolling
connection
Task-ID 28188
