class ActionMailbox::Ingresses::Relay::InboundEmailsController

Ingests inbound emails relayed from an SMTP server.

Authenticates requests using HTTP basic access authentication. The username is always actionmailbox, and the password is read from the application’s encrypted credentials or an environment variable. See the Usage section below.

Note that basic authentication is insecure over unencrypted HTTP. An attacker that intercepts cleartext requests to the ingress can learn its password. You should only use this ingress over HTTPS.

Returns:

• 204 No Content if an inbound email is successfully recorded and enqueued for routing to the appropriate mailbox

• 401 Unauthorized if the request could not be authenticated

• 404 Not Found if Action Mailbox is not configured to accept inbound emails relayed from an SMTP server

• 415 Unsupported Media Type if the request does not contain an RFC 822 message

• 500 Server Error if the ingress password is not configured, or if one of the Active Record database, the Active Storage service, or the Active Job backend is misconfigured or unavailable

Usage

1. Tell Action Mailbox to accept emails from an SMTP relay:

   # config/environments/production.rb
   config.action_mailbox.ingress = :relay
   

2. Generate a strong password that Action Mailbox can use to authenticate requests to the ingress.

   Use bin/rails credentials:edit to add the password to your application’s encrypted credentials under action_mailbox.ingress_password, where Action Mailbox will automatically find it:

   action_mailbox:
     ingress_password: ...
   

   Alternatively, provide the password in the RAILS_INBOUND_EMAIL_PASSWORD environment variable.

3. Configure your SMTP server to pipe inbound emails to the appropriate ingress command, providing the URL of the relay ingress and the INGRESS_PASSWORD you previously generated.

   If your application lives at https://example.com, you would configure the Postfix SMTP server to pipe inbound emails to the following command:

   $ bin/rails action_mailbox:ingress:postfix URL=https://example.com/rails/action_mailbox/postfix/inbound_emails INGRESS_PASSWORD=...
   

   Built-in ingress commands are available for these popular SMTP servers:

   • Exim (bin/rails action_mailbox:ingress:exim)

   • Postfix (bin/rails action_mailbox:ingress:postfix)

   • Qmail (bin/rails action_mailbox:ingress:qmail)