Email Gathering with Fetchmail

To enable the fetchmail service to retrieve e-mails set the environment variable ENABLE_FETCHMAIL to 1. Your docker-compose.yml file should look like following snippet:

environment:
  - ENABLE_FETCHMAIL=1
  - FETCHMAIL_POLL=300

Generate a file called fetchmail.cf and place it in the docker-data/dms/config/ folder. Your docker-mailserver folder should look like this example:

├── docker-data/dms/config
│   ├── dovecot.cf
│   ├── fetchmail.cf
│   ├── postfix-accounts.cf
│   └── postfix-virtual.cf
├── docker-compose.yml
└── README.md

Configuration

A detailed description of the configuration options can be found in the online version of the manual page.

IMAP Configuration

Example

poll 'imap.gmail.com' proto imap
  user 'username'
  pass 'secret'
  is 'user1@example.com'
  ssl

POP3 Configuration

Example

poll 'pop3.gmail.com' proto pop3
  user 'username'
  pass 'secret'
  is 'user2@example.com'
  ssl

Caution

Don’t forget the last line! (eg: is 'user1@example.com'). After is, you have to specify an email address from the configuration file: docker-data/dms/config/postfix-accounts.cf.

More details how to configure fetchmail can be found in the fetchmail man page in the chapter “The run control file”.

Polling Interval

By default the fetchmail service searches every 5 minutes for new mails on your external mail accounts. You can override this default value by changing the ENV variable FETCHMAIL_POLL:

environment:
  - FETCHMAIL_POLL=60

You must specify a numeric argument which is a polling interval in seconds. The example above polls every minute for new mails.

Debugging

To debug your fetchmail.cf configuration run this command:

./setup.sh debug fetchmail

For more informations about the configuration script setup.sh read the corresponding docs.

Here a sample output of ./setup.sh debug fetchmail:

fetchmail: 6.3.26 querying outlook.office365.com (protocol POP3) at Mon Aug 29 22:11:09 2016: poll started
Trying to connect to 132.245.48.18/995...connected.
fetchmail: Server certificate:
fetchmail: Issuer Organization: Microsoft Corporation
fetchmail: Issuer CommonName: Microsoft IT SSL SHA2
fetchmail: Subject CommonName: outlook.com
fetchmail: Subject Alternative Name: outlook.com
fetchmail: Subject Alternative Name: *.outlook.com
fetchmail: Subject Alternative Name: office365.com
fetchmail: Subject Alternative Name: *.office365.com
fetchmail: Subject Alternative Name: *.live.com
fetchmail: Subject Alternative Name: *.internal.outlook.com
fetchmail: Subject Alternative Name: *.outlook.office365.com
fetchmail: Subject Alternative Name: outlook.office.com
fetchmail: Subject Alternative Name: attachment.outlook.office.net
fetchmail: Subject Alternative Name: attachment.outlook.officeppe.net
fetchmail: Subject Alternative Name: *.office.com
fetchmail: outlook.office365.com key fingerprint: 3A:A4:58:42:56:CD:BD:11:19:5B:CF:1E:85:16:8E:4D
fetchmail: POP3< +OK The Microsoft Exchange POP3 service is ready. [SABFADEAUABSADAAMQBDAEEAMAAwADAANwAuAGUAdQByAHAAcgBkADAAMQAuAHAAcgBvAGQALgBlAHgAYwBoAGEAbgBnAGUAbABhAGIAcwAuAGMAbwBtAA==]
fetchmail: POP3> CAPA
fetchmail: POP3< +OK
fetchmail: POP3< TOP
fetchmail: POP3< UIDL
fetchmail: POP3< SASL PLAIN
fetchmail: POP3< USER
fetchmail: POP3< .
fetchmail: POP3> USER user1@outlook.com
fetchmail: POP3< +OK
fetchmail: POP3> PASS *
fetchmail: POP3< +OK User successfully logged on.
fetchmail: POP3> STAT
fetchmail: POP3< +OK 0 0
fetchmail: No mail for user1@outlook.com at outlook.office365.com
fetchmail: POP3> QUIT
fetchmail: POP3< +OK Microsoft Exchange Server 2016 POP3 server signing off.
fetchmail: 6.3.26 querying outlook.office365.com (protocol POP3) at Mon Aug 29 22:11:11 2016: poll completed
fetchmail: normal termination, status 1