feat: mailig list rule

1 files changed, 21 insertions, 0 deletions

diff --git a/filters/mailing_lists_filter.rb b/filters/mailing_lists_filter.rb
new file mode 100644
index 0000000..872a817
--- /dev/null
+++ b/filters/mailing_lists_filter.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+module Chotto
+  # Adds "list" and "list/<list-id>" tags to messages from mailing list
+  # Baed on RFC 2919
+  module MailingListsFilter
+    def self.list_id_from_header(value)
+      value.match(/<(.*)>/)[1].gsub(' ', '')
+    end
+  end
+end
+
+MAILING_LIST_FILTER = lambda do
+  Chotto.rule_set 'mailing_lists' do
+    messages.filter('NOT tag:lists').each do |msg|
+      list_id = Chotto::MailingListsFilter.list_id_from_header(msg.list_id)
+      msg.tags = ['unread', 'inbox', 'lists', "lists/#{list_id}"]
+      msg.save!
+    end
+  end
+end