115 lines
4.2 KiB
Ruby
115 lines
4.2 KiB
Ruby
# frozen_string_literal: true
|
|
|
|
module Email
|
|
##
|
|
# Email Message-IDs are used in both our outbound and inbound email
|
|
# flow. For the outbound flow via Email::Sender, we assign a unique
|
|
# Message-ID for any emails sent out from the application.
|
|
# If we are sending an email related to a topic, such as through the
|
|
# PostAlerter class, then the Message-ID will contain references to
|
|
# the topic ID, and if it is for a specific post, the post ID,
|
|
# along with a random suffix to make the Message-ID truly unique.
|
|
# The host must also be included on the Message-IDs.
|
|
#
|
|
# For the inbound email flow via Email::Receiver, we use Message-IDs
|
|
# to discern which topic or post the inbound email reply should be
|
|
# in response to. In this case, the Message-ID is extracted from the
|
|
# References and/or In-Reply-To headers, and compared with either
|
|
# the IncomingEmail table, the Post table, or the IncomingEmail to
|
|
# determine where to send the reply.
|
|
#
|
|
# See https://datatracker.ietf.org/doc/html/rfc2822#section-3.6.4 for
|
|
# more specific information around Message-IDs in email.
|
|
#
|
|
# See https://tools.ietf.org/html/rfc850#section-2.1.7 for the
|
|
# Message-ID format specification.
|
|
class MessageIdService
|
|
class << self
|
|
def generate_default
|
|
"<#{SecureRandom.uuid}@#{host}>"
|
|
end
|
|
|
|
def generate_for_post(post, use_incoming_email_if_present: false)
|
|
if use_incoming_email_if_present && post.incoming_email&.message_id.present?
|
|
return "<#{post.incoming_email.message_id}>"
|
|
end
|
|
|
|
"<topic/#{post.topic_id}/#{post.id}.#{random_suffix}@#{host}>"
|
|
end
|
|
|
|
def generate_for_topic(topic, use_incoming_email_if_present: false, canonical: false)
|
|
first_post = topic.ordered_posts.first
|
|
incoming_email = first_post.incoming_email
|
|
|
|
# If the incoming email was created by handle_mail, then it was an
|
|
# inbound email sent to Discourse and handled by Email::Receiver,
|
|
# this is the only case where we want to use the original Message-ID
|
|
# because we want to maintain threading in the original mail client.
|
|
if use_incoming_email_if_present &&
|
|
incoming_email&.message_id.present? &&
|
|
incoming_email&.created_via == IncomingEmail.created_via_types[:handle_mail]
|
|
return "<#{first_post.incoming_email.message_id}>"
|
|
end
|
|
|
|
if canonical
|
|
"<topic/#{topic.id}@#{host}>"
|
|
else
|
|
"<topic/#{topic.id}.#{random_suffix}@#{host}>"
|
|
end
|
|
end
|
|
|
|
def find_post_from_message_ids(message_ids)
|
|
message_ids = message_ids.map { |message_id| message_id_clean(message_id) }
|
|
post_ids = message_ids.map { |message_id| message_id[message_id_post_id_regexp, 1] }.compact.map(&:to_i)
|
|
post_ids << Post.where(
|
|
topic_id: message_ids.map { |message_id| message_id[message_id_topic_id_regexp, 1] }.compact,
|
|
post_number: 1
|
|
).pluck(:id)
|
|
post_ids << EmailLog.where(message_id: message_ids).pluck(:post_id)
|
|
post_ids << IncomingEmail.where(message_id: message_ids).pluck(:post_id)
|
|
|
|
post_ids.flatten!
|
|
post_ids.compact!
|
|
post_ids.uniq!
|
|
|
|
return if post_ids.empty?
|
|
|
|
Post.where(id: post_ids).order(:created_at).last
|
|
end
|
|
|
|
def random_suffix
|
|
SecureRandom.hex(12)
|
|
end
|
|
|
|
def discourse_generated_message_id?(message_id)
|
|
!!(message_id =~ message_id_post_id_regexp) ||
|
|
!!(message_id =~ message_id_topic_id_regexp)
|
|
end
|
|
|
|
def message_id_post_id_regexp
|
|
Regexp.new "topic/\\d+/(\\d+|\\d+\.\\w+)@#{Regexp.escape(host)}"
|
|
end
|
|
|
|
def message_id_topic_id_regexp
|
|
Regexp.new "topic/(\\d+|\\d+\.\\w+)@#{Regexp.escape(host)}"
|
|
end
|
|
|
|
def message_id_rfc_format(message_id)
|
|
message_id.present? && !is_message_id_rfc?(message_id) ? "<#{message_id}>" : message_id
|
|
end
|
|
|
|
def message_id_clean(message_id)
|
|
message_id.present? && is_message_id_rfc?(message_id) ? message_id.gsub(/^<|>$/, "") : message_id
|
|
end
|
|
|
|
def is_message_id_rfc?(message_id)
|
|
message_id.start_with?('<') && message_id.include?('@') && message_id.end_with?('>')
|
|
end
|
|
|
|
def host
|
|
Email::Sender.host_for(Discourse.base_url)
|
|
end
|
|
end
|
|
end
|
|
end
|