GitLab can be set up to allow users to comment on issues and merge requests by replying to notification emails.
Reply by email requires an IMAP-enabled email account. GitLab allows you to use three strategies for this feature:
- using email sub-addressing
- using a dedicated email address
- using a catch-all mailbox
If your provider or server supports email sub-addressing, we recommend using it.
Sub-addressing is
a feature where any email to [email protected]
will end up
in the mailbox for [email protected]
, and is supported by providers such as
Gmail, Google Apps, Yahoo! Mail, Outlook.com and iCloud, as well as the Postfix
mail server which you can run on-premises.
This solution is really simple to set up: you just have to create an email address dedicated to receive your users' replies to GitLab notifications.
A catch-all mailbox for a domain will "catch all" the emails addressed to the domain that do not exist in the mail server.
When GitLab sends a notification and Reply by email is enabled, the Reply-To
header is set to the address defined in your GitLab configuration, with the
%{key}
placeholder (if present) replaced by a specific "reply key". In
addition, this "reply key" is also added to the References
header.
When you reply to the notification email, your email client will:
- send the email to the
Reply-To
address it got from the notification email - set the
In-Reply-To
header to the value of theMessage-ID
header from the notification email - set the
References
header to the value of theMessage-ID
plus the value of the notification email'sReferences
header.
When GitLab receives your reply, it will look for the "reply key" in the following headers, in this order:
- the
To
header - the
References
header
If it finds a reply key, it will be able to leave your reply as a comment on the entity the notification was about (issue, merge request, commit...).
For more details about the Message-ID
, In-Reply-To
, and References headers
,
please consult RFC 5322.
If you want to use Gmail / Google Apps with Reply by email, make sure you have IMAP access enabled and allowed less secure apps to access the account.
To set up a basic Postfix mail server with IMAP access on Ubuntu, follow these instructions.
-
Find the
incoming_email
section in/etc/gitlab/gitlab.rb
, enable the feature and fill in the details for your specific IMAP server and email account:# Configuration for Postfix mail server, assumes mailbox [email protected] gitlab_rails['incoming_email_enabled'] = true # The email address including the `%{key}` placeholder that will be replaced to reference the item being replied to. # The placeholder can be omitted but if present, it must appear in the "user" part of the address (before the `@`). gitlab_rails['incoming_email_address'] = "incoming+%{key}@gitlab.example.com" # Email account username # With third party providers, this is usually the full email address. # With self-hosted email servers, this is usually the user part of the email address. gitlab_rails['incoming_email_email'] = "incoming" # Email account password gitlab_rails['incoming_email_password'] = "[REDACTED]" # IMAP server host gitlab_rails['incoming_email_host'] = "gitlab.example.com" # IMAP server port gitlab_rails['incoming_email_port'] = 143 # Whether the IMAP server uses SSL gitlab_rails['incoming_email_ssl'] = false # Whether the IMAP server uses StartTLS gitlab_rails['incoming_email_start_tls'] = false # The mailbox where incoming mail will end up. Usually "inbox". gitlab_rails['incoming_email_mailbox_name'] = "inbox"
# Configuration for Gmail / Google Apps, assumes mailbox [email protected] gitlab_rails['incoming_email_enabled'] = true # The email address including the `%{key}` placeholder that will be replaced to reference the item being replied to. # The placeholder can be omitted but if present, it must appear in the "user" part of the address (before the `@`). gitlab_rails['incoming_email_address'] = "gitlab-incoming+%{key}@gmail.com" # Email account username # With third party providers, this is usually the full email address. # With self-hosted email servers, this is usually the user part of the email address. gitlab_rails['incoming_email_email'] = "[email protected]" # Email account password gitlab_rails['incoming_email_password'] = "[REDACTED]" # IMAP server host gitlab_rails['incoming_email_host'] = "imap.gmail.com" # IMAP server port gitlab_rails['incoming_email_port'] = 993 # Whether the IMAP server uses SSL gitlab_rails['incoming_email_ssl'] = true # Whether the IMAP server uses StartTLS gitlab_rails['incoming_email_start_tls'] = false # The mailbox where incoming mail will end up. Usually "inbox". gitlab_rails['incoming_email_mailbox_name'] = "inbox"
-
Reconfigure GitLab and restart mailroom for the changes to take effect:
sudo gitlab-ctl reconfigure sudo gitlab-ctl restart mailroom
-
Verify that everything is configured correctly:
sudo gitlab-rake gitlab:incoming_email:check
-
Reply by email should now be working.
-
Go to the GitLab installation directory:
cd /home/git/gitlab
-
Find the
incoming_email
section inconfig/gitlab.yml
, enable the feature and fill in the details for your specific IMAP server and email account:sudo editor config/gitlab.yml
# Configuration for Postfix mail server, assumes mailbox [email protected] incoming_email: enabled: true # The email address including the `%{key}` placeholder that will be replaced to reference the item being replied to. # The placeholder can be omitted but if present, it must appear in the "user" part of the address (before the `@`). address: "incoming+%{key}@gitlab.example.com" # Email account username # With third party providers, this is usually the full email address. # With self-hosted email servers, this is usually the user part of the email address. user: "incoming" # Email account password password: "[REDACTED]" # IMAP server host host: "gitlab.example.com" # IMAP server port port: 143 # Whether the IMAP server uses SSL ssl: false # Whether the IMAP server uses StartTLS start_tls: false # The mailbox where incoming mail will end up. Usually "inbox". mailbox: "inbox"
# Configuration for Gmail / Google Apps, assumes mailbox [email protected] incoming_email: enabled: true # The email address including the `%{key}` placeholder that will be replaced to reference the item being replied to. # The placeholder can be omitted but if present, it must appear in the "user" part of the address (before the `@`). address: "gitlab-incoming+%{key}@gmail.com" # Email account username # With third party providers, this is usually the full email address. # With self-hosted email servers, this is usually the user part of the email address. user: "[email protected]" # Email account password password: "[REDACTED]" # IMAP server host host: "imap.gmail.com" # IMAP server port port: 993 # Whether the IMAP server uses SSL ssl: true # Whether the IMAP server uses StartTLS start_tls: false # The mailbox where incoming mail will end up. Usually "inbox". mailbox: "inbox"
-
Enable
mail_room
in the init script at/etc/default/gitlab
:sudo mkdir -p /etc/default echo 'mail_room_enabled=true' | sudo tee -a /etc/default/gitlab
-
Restart GitLab:
sudo service gitlab restart
-
Verify that everything is configured correctly:
sudo -u git -H bundle exec rake gitlab:incoming_email:check RAILS_ENV=production
-
Reply by email should now be working.
-
Go to the GitLab installation directory.
-
Find the
incoming_email
section inconfig/gitlab.yml
, enable the feature and fill in the details for your specific IMAP server and email account:# Configuration for Gmail / Google Apps, assumes mailbox [email protected] incoming_email: enabled: true # The email address including the `%{key}` placeholder that will be replaced to reference the item being replied to. # The placeholder can be omitted but if present, it must appear in the "user" part of the address (before the `@`). address: "gitlab-incoming+%{key}@gmail.com" # Email account username # With third party providers, this is usually the full email address. # With self-hosted email servers, this is usually the user part of the email address. user: "[email protected]" # Email account password password: "[REDACTED]" # IMAP server host host: "imap.gmail.com" # IMAP server port port: 993 # Whether the IMAP server uses SSL ssl: true # Whether the IMAP server uses StartTLS start_tls: false # The mailbox where incoming mail will end up. Usually "inbox". mailbox: "inbox"
As mentioned, the part after
+
is ignored, and this will end up in the mailbox for[email protected]
. -
Uncomment the
mail_room
line in yourProcfile
:mail_room: bundle exec mail_room -q -c config/mail_room.yml
-
Restart GitLab:
bundle exec foreman start
-
Verify that everything is configured correctly:
bundle exec rake gitlab:incoming_email:check RAILS_ENV=development
-
Reply by email should now be working.