Chotto

Notmuch ecosystem already has a great script for initial tagging - afew. However it is written in Python and therefore it's always a gamble if it will consider the user worthy or running.

Chotto, a few in Japanese. Because afew refused to work on my system. And because I love Ruby!

Chotto expects:

• ruby 3x
• notmuch
• notmuch ruby bindings.

While the first 2 are obvious, getting ruby bindings to work may be an adventure on its own.

FreeBSD provides a ready package ruby-notmuch.

MacOS requires compiling from source, which will be problematic due to linking difficulties. It's not an OS designed for technical folks.

Some Linux distros provide the bindings in their package managers, but otherwise compiling should be easy.

If you use Windows, you have my sympathy.

Chotto expects the configuration file to be present in

~/.config/chotto/config.rb

The user needs to add (at least) two blocks to the file: config & rule sets

Presently, the only option Config expects is the absolute path to the Notmuch database:

Chotto.configure do
  config.database_path = =/home/<user>/mail=
end

Please, adjust the path to the valid location

The actual magic happens in Rule Sets which are sets of filters & tag modifications. A very simple rule set can look like:

Chotto.rule_set "notes" do
  messages.filter(from: "<my email>").each do |msg|
     msg.tags << "note" 
     msg.save!
  end
end

Let's break it down.

First, we define a named rule_set. The name can be a string or a hash and is currently not used anywhere. It makes it easier to manager bigger rule sets.

Then we search for messages. In this case, we want all messages sent from <my email> .

After, we loop over each found message.

msg.tags returns a mutable array, and we can mutate is as such.

Lastly, we save! the message in the database.

We can quite easily filter messages based. Chotto accepts filters as:

• Strings (from(Subject:Hired!)). The string will not be modified.

• Hash with string values (from(subject: Hired)). The key of each hash element is a modified header value - it's down cased, and - becomes _, therefore:

  • X-Spam-Id becomes x_spam_id
  • X-Thread-Id becomes x_thread_id

  The values on the other hand can be:

  • String. Kind of obvious.
  • Array. Arrays here are treated as the current conjunctions. The default conjunction here is OR, so k: [1,2] will become key:1 OR key:2

  User can add multiple elements to the hash, and they will be join in the current conjunction mode. By default the mode is AND, therefore:

  {key: 'val1', key2: 'val2'} are treated as key:val1 AND key2:val2.

  filter returns self, therefore we can combine multiple filters filter(key1: 'val').filter(key2: 'val2'). Filters will be joined in the current conjunction mode.

  Conjunction mode can be changed using the or and and methods: filter(key1: val1).or.filter(key2: val2).

  The language is simple, but gives huge chances to go wrong. You can test what is produced by calling #to_query_string on messages instance.