This plugin adds DKIM signature to all outgoing emails.

1. Generate DKIM public and private keys. You can do it for example here: https://tools.socketlabs.com/dkim/generator If running an application on a subdomain, enter subdomain.domain.tld in the domain field, otherwise enter domain.tld.

2. On your domain create TXT DNS entry with the public part of the key, for example a record with name (domain name): dkim._domainkey.subdomain.domain.tld

   Where dkim is the selector used while generating the key in step 1.

   The record value is:

   v=DKIM1; k=rsa; p=<public key>
   

   Check DNS with this tool: https://mxtoolbox.com/supertool3 Type the domain name and select DKIM Lookup. Domain should be in the format:

   subdomain.domain.tld:selector
   

   For example:

   example.com:dkim
   

3. Copy the private key to some file, for example storage/app/uploads/protected/dkim/private.key

   !!! This file should not be accessible from the web so we will save it to a protected directory !!!

4. Setup plugin by .env file:

   Below you can see all possible variables with default values:

   DKIM_ENABLED=false
   DKIM_PRIVATE_KEY=
   DKIM_DOMAIN=<config.app.url>
   DKIM_SELECTOR=dkim
   DKIM_PASSPHRASE=

   For my example it is enough to set:

   DKIM_ENABLED=true
   DKIM_PRIVATE_KEY=storage/app/uploads/protected/dkim/private.key

   A domain is by default taken from config app.url. A selector is by default dkim. A passphrase is empty by default.

5. Send testing email to Gmail recipient where you find Show original in the mail detail and there you should see: DKIM PASS.

Please send Pull Request to the master branch.

Fakturoid plugin is open-sourced software licensed under the MIT license same as OctoberCMS platform.