Default variable details: opendkim__config

The opendkim__*_config variables are used to define the contents of the /etc/opendkim.conf configuration file. The variables are YAML lists, concatenated together into opendkim__combined_config variable, which is passed to the configuration template.

Each list entry is a YAML dictionary, which can be written in a simple or complex form. Entries that control OpenDKIM parameters of the same name will be combined together in order of appearance.

Simple form of the configuration parameters

Simple form of the OpenDKIM configuration uses the dictionary key as a option name, and its value as that option's parameters:

opendkim__config:

  # Option with boolean value
  - Syslog: True

  # Option with integer value
  - AutoRestartCount: 0

  # Option with string value
  - Domain: 'example.com'

  # Option with multiple values in a list
  - OversignHeaders: [ 'Header1', 'Header2' ]

The result of the above configuration in /etc/opendkim.conf:

Syslog              yes
AutoRestartCount    0
Domain              example.com
OversignHeaders     Header1,Header2

The parameters in the configuration file will be present in the order they were first defined in the variables.

Complex form of the configuration parameters

Complex form of the OpenDKIM configuration is detected when a dictionary key contains a name parameter. In that case, the role will interpret the entry using specific parameters:

name

The name of the configuration option to manage. This parameter is used as an identifier during the variable parsing.

value

Required. A value which should be set for a given option. Values can be YAML strings, integers, booleans and lists (not dictionaries). Lists can contain simple strings, numbers, or YAML dictionaries that describe each value in greater detail. See Configuration values and their interactions for more details.

option

Optional. If specified, the option will use this string as the "name" instead of the name value. This is useful to create examples in the configuration file that have the same name as existing configuration options.

comment

Optional. String or a YAML dictionary with additional comments for a given configuration option.

separator

Optional, boolean. if True, an empty line will be added above a given option, useful for readability.

state

Optional. If not specified or present, the option will be present in the finished configuration file.

If absent, the option will not be included in the configuration file.

If ignore, the given entry will not be evaluated by the role, and no changes will be done to the preceding parameters with the same name. This can be used to conditionally activate entries with different configuration.

If hidden, the option will not be displayed in the configuration file, but any comments will be present. This can be used to add free-form comments in the Postfix configuration file.

If comment, the option will be present, but it will be commented out. This can be used to add examples in the configuration file.

weight

Optional. A positive or negative number which affects the position of a given option in the configuration file. The higher the number, the more a given option "weighs" and the lower it will be placed in the finished configuration file. Negative numbers make the option "lighter" and it will be placed higher.

copy_id_from

Optional. This is an internal role parameter which can be used to change the relative position of a given option in the configuration file. If you specify a name of an option, it's internal "id" number (used for sorting) will be copied to the current option. This can be used to move options around to different configuration file sections.

Examples

Define the previous example using complex form:

opendkim__config:

  - name: 'Syslog'
    comment: 'Log to syslog'
    value: True

  - name: 'AutoRestartCount'
    value: 0

  - name: 'Domain'
    value: 'example.com'

  - name: 'OversignHeaders'
    value: [ 'Header1', 'Header2' ]

The result of the above configuration in /etc/postfix/main.cf:

# Log to syslog
Syslog              yes

AutoRestartCount    0
Domain              example.com
OversignHeaders     Header1,Header2

The parameters in the configuration file will be present in the order they were first defined in the variables, unless the weight parameter is added, which will change the order.

Configuration values and their interactions

The OpenDKIM configuration file uses key-value format, with values being either strings, numbers, booleans or lists. The first three types are handled by the debops.opendkim role as normal.

List values are by default concatenated to allow easy extension of existing values. The values in a list are either YAML strings, numbers, or can be defined as YAML dictionaries with specific parameters:

name or param

Required. The value itself, usually a string.

state

Optional. If not defined or present, the value will be included in the list.

If absent, the value will be removed from the list.

If ignore, the given entry will not be evaluated by the role, and will not change the state of the value. This can be used to enable or disable values conditionally.

weight

Optional. A positive or negative number which affects the position of a given value in the list. The higher the number, the more a given value "weighs" and the lower it will be placed in the finished list. Negative numbers make the value "lighter" and it will be placed higher.

Example list

Define a list with conditional values:

opendkim__config:

  - name: 'OversignHeaders'
    value:

      - 'From'

      - name: 'To'
        state: '{{ "present"
                   if (ansible_domain.split(".")|count > 1)
                   else "ignore" }}'

      - name: 'Subject'
        weight: 100

Base value replacement

Repeating the string, number or boolean option will result in the latter entry replacing the former entry:

opendkim__config:

  # Old value
  - Domain: 'example.com'

  # New, active value
  - Domain: 'example.org'

The result of the above configuration in /etc/opendkim.conf:

Domain          example.org

Lists are merged together

The list parameters behave differently. Specifying the same option multiple times, if the preceding option was a list, will add the specified parameters to the list:

opendkim__config:

  - InternalHosts: [ '127.0.0.1', 'localhost' ]

  - InternalHosts: [ '192.0.2.1' ]

The result of the above configuration in /etc/opendkim.conf:

InternalHosts          127.0.0.1,localhost,192.0.2.1

How to reset a list

If the option was a list, and subsequent option specified a boolean, string or a number, the value will replace the previous one, instead of adding to a list. This can be used to reset the list instead of appending to it.

opendkim__config:

  - InternalHosts: [ '127.0.0.1', '::1' ]

  - Internalhosts: 'localhost'

The result of the above configuration in /etc/opendkim.conf:

InternalHosts          localhost

Lists don't add duplicates

The role checks if a given list element is already present, and it won't add a duplicate value to the list:

opendkim__config:

  - Domain: [ 'example.org', 'localhost' ]

  - Domain: [ 'example.org' ]

The result of the above configuration in /etc/opendkim.conf:

Domain           example.org,localhost