Entries tagged lumail2

Once upon a time I wrote a mail-client, which worked in the console directly via Maildir manipulation.

My mail client was written in C++, and used Lua for scripting unlike clients such as mutt, alpine, and similar alternatives which don't have complete scripting support.

I've pondered several times whether to restart this project, but I think it is the right thing to do.

The original lumail client has a rich API, but it is very ad-hoc and random. Functions were added where they seemed like a good idea, but with no real planning, and although there are grouped functions that operate similarly there isn't a lot of consistency. The implementation is clean in places, elegant in others, and horrid in yet more parts.

This time round everything is an object, accessible to Lua, with Lua, and for Lua. This time round all the drawing-magic is will be written in Lua.

So to display a list of Maildirs I create a bunch of objects, one for each Maildir, and then the Lua function Maildir.to_string is called. That function looks like this:

--
-- This method returns the text which is displayed when a maildir is
-- to be show in maildir-mode.
--
function Maildir.to_string(self)
   local total  = self:total_messages()
   local unread = self:unread_messages()
   local path   = self:path()

   local output = string.format( "[%05d / %05d] - %s", unread, total, path );

   if ( unread > 0 ) then
      output = "$[RED]" .. output
   end

   if ( string.find( output, "Automated." ) ) then
      output = strip_colour( output )
      output = "$[YELLOW]" .. output
   end

   return output
end

The end result is something that looks like this:

[00001 / 00010 ] - Amazon.de
[00000 / 00023 ] - Automated.root

The formatting can thus be adjusted clearly, easily, and without hacking the core of the client. Providing I implement the apporpriate methods to the Maildir object.

It's still work in progress. You can view maildirs, view indexes, and view messages. You cannot reply, forward, or scroll properly. That said the hard part is done now, and I'm reasonably happy with it.

The sample configuration file is a bit verbose, but a good demonstration regardless.

See the code, if you wish, online here:

• https://github.com/lumail/lumail2/

Tags: lua, lumail, lumail2 | 2 comments

So the work on lumail2 is going well, and already I can see that it is a good idea. The main reason for (re)writing it is to unify a lot of the previous ad-hoc primitives (i.e. lua functions) and to try and push as much of the code into Lua, and out of C++, as possible. This work is already paying off with the introduction of new display-modes and simpler implementation.

View modes are an important part of lumail, because it is a modal mail-client. You're always in one mode:

• maildir-mode
  • Shows you lists of Maildir-folders.
• index-mode
  • Shows you lists of messages inside the maildir you selected.
• message-mode
  • Shows you a single message.

This is nothing new, but there are two new modes:

• attachment-mode
  • Shows you the attachments associated with the current message.
• lua-mode
  • Shows you your configuration-settings and trivia.

Each of these modes draws lines of text on the screen, and those lines consist of things that Lua generated. So there is a direct mapping:

With that in mind it is possible to write a function to scroll to the next line containing a pattern like so:

function find()
   local pattern = Screen:get_line( "Search for:" )

   -- Get the global mode.
   local mode = Config:get("global.mode")

   -- Use that to get the lines we're currently displaying
   loadstring( "out = " .. mode .. "_view()" )()

   -- At this point "out" is a table containing lines that
   -- the current mode wishes to display.

    -- .. do searching here.
end

Thus the whole thing is dynamic and mode-agnostic.

The other big change is pushing things to lua. So to reply to an email, populating the new message, appending your ~/.signature, is handled by Lua. As is forwarding a message, or composing a new mail.

The downside is that the configuration-file is now almost 1000 lines long, thanks to the many little function definitions, and key-binding setup.

At this rate the first test-release will be out at the weekend, but API documentation, and sample configuration file might make interesting reading until then.

Tags: lumail2 | No comments

I'm pleased with the way that Lumail2 development is proceeding, and it is reaching a point where there will be a second source-release.

I've made a lot of changes to the repository recently, and most of them boil down to moving code from the C++ side of the application, over to the Lua side.

This morning, for example, I updated the handing of index.limit to be entirely Lua based.

When you open a Maildir folder you see the list of messages it contains, as you would expect.

The notion of the index.limit is that you can limit the messages displayed, for example:

• See all messages: Config:set( "index.limit", "all")
• See only new/unread messages: Config:set( "index.limit", "new")
• See only messages which arrived today: Config:set( "index.limit", "today")
• See only messages which contain "Steve" in their formatted version: Config:set( "index.limit", "steve")

These are just examples that are present as defaults, but they give an idea of how things can work. I guess it isn't so different to Mutt's "limit" facilities - but thanks to the dynamic Lua nature of the application you can add your own with relative ease.

One of the biggest changes, recently, was the ability to display coloured text! That was always possible before, but a single line could only be one colour. Now colours can be mixed within a line, so this works as you might imagine:

Other changes include a persistant cache of "stuff", which is Lua-based, the inclusion of at least one luarocks library to parse Date: headers, and a simple API for all our objects.

All good stuff. Perhaps time for a break in the next few weeks, but right now I think I'm making useful updates every other evening or so.

Tags: lua, lumail2 | No comments

A couple of years ago I was dissatisfied with mutt, mostly because the mutt-sidebar patch was dropped from the Debian package. That lead to me thinking "How hard can it be to write a modal, console-based mail-client?"

It turns out writing a client is pretty simple if you limit yourself solely to Maildirs, and as I typically read my mail over SSH on the mailhost itself that suited me pretty well.

Recently I restarted the mail-client. Putting it together from scratch to simplify the implementation, and unify a lot of the adhoc scripting which is provided by Lua. People seem to like the client, but the single largest complaint was "Can't use it - no IMAP."

This week I've mostly been adding IMAP support, and today I'll commit the last few bits that mean it is roughly-functional:

• Connecting to a mail-server works.
• Getting the folders works.
• Getting the messages works.

The outstanding niggles will be relating to getting/setting the new/read/seen/unseen flags, and similar. But I'm pleased that the job wasn't insurmountable.

I've used libcurl to provide the IMAP functionality because most of the IMAP libraries I looked at were big, scary, and complex. Using curl to access IMAP is pretty neat, simple, and straightforward. The downside is you're making a lot of "http" requests. So I might need to revisit things.

Happily my imap wrapper doesn't need much functionality. So if I can find a better library swapping it out will be simple.

In conclusion: Lumail almost has IMAP support, and that might mean it'll be more useful to others.

Tags: imap, lumail, lumail2 | No comments