SpamAssassin - Make possible to add plugin configuration definitions

config.php

<?php
/**
 * i-MSCP SpamAssassin plugin
 * Copyright (C) 2015-2018 Laurent Declercq <l.declercq@nuxwin.com>
 * Copyright (C) 2013-2016 Rene Schuster <mail@reneschuster.de>
 * Copyright (C) 2013-2018 Sascha Bay <info@space2place.de>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

return [
    // SPAMD(8p) service configuration
    'spamd'          => [
        // SPAMD(8p) unix user
        'user'    => 'debian-spamd',

        // SPAMD(8p) unix user group
        'group'   => 'debian-spamd',

        // SPAMD(8p) unix user homedir
        'homedir' => '/var/lib/spamassassin',

        // Options passed-in to SPAMD(8p)
        //
        // Available placeholders:
        //  - {SPAMD_USER}: Replaced by SPAMD(8p) unix user
        //  - {SPAMD_GROUP}: Replaced by SPAMD(8p) unix user group
        //  - {SPAMD_HOMEDIR}: Replaced by SPAMD(8p) unix user homedir
        'options' => '--max-children=5 --sql-config --nouser-config --username={SPAMD_USER} --groupname={SPAMD_GROUP}'
            . ' --helper-home-dir={SPAMD_HOMEDIR} --socketpath=/var/run/spamassassin.sock --socketowner={SPAMD_USER}'
            . ' --socketgroup={SPAMD_GROUP} --socketmode=0666'
    ],

    // SPAMASS_MILTER(8) service configuration
    'spamass_milter' => [
        // Policy for SPAM rejection
        //
        // - If set to -1, SPAM messages are always rejected.
        // - If set to 15, SPAM messages are only rejected when the score is
        //   equal or greater then 15. SPAM messages below that score are
        //   tagged as SPAM.
        // - If set to a value higher than 1000, SPAM messages are never
        //   rejected. SPAM messages are tagged as SPAM.
        //
        // Generally speaking, an ISP shouldn't automatically remove SPAM
        // messages. Decision should be left to end-user, hence the default
        // value that is a good compromise.
        'spam_reject_policy'      => 15,

        // Ignores messages if the sender has authenticated via SMTP AUTH.
        //
        // If set to TRUE messages from authenticated senders (SASL) will
        // passthrough without being scanned.
        'ignore_auth_sender_msgs' => false,

        // Ignore messages from listed networks
        //
        // Messages from listed networks will passthrough without being
        // scanned.
        //
        // An array where each element can be either:
        // - An IP address: nnn.nnn.nnn.nnn
        // - A CIDR network: nnn.nnn.nnn.nnn/nn
        // - A network/netmask pair: nnn.nnn.nnn.nnn/nnn.nnn.nnn.nnn
        // For instance: '127.0.0.1', '172.16.12.0/24', '10.0.0.0/255.0.0.0'
        'networks'                => [],

        // Options passed-in to SPAMASS_MILTER(8)
        //
        // You can pass your own options to SPAMASS_MILTER(8), including flags
        // for SPAMC(1) as described in SPAMASS_MILTER(8)
        //
        // Don't add the -I, -i and -r SPAMASS_MILTER(8) options as these are
        // managed through the named options above.
        'options'                 => '-e localhost -f -u spamass-milter -- --max-size=2048000 --socket=/var/run/spamassassin.sock',

        // SPAMASS_MILTER(8) socket path
        'socket_path'             => '/var/spool/postfix/spamass/spamass.sock',

        // SPAMASS_MILTER(8) socket owner
        'socket_owner'            => 'postfix:postfix',

        // SPAMASS_MILTER(8) socket mode
        'socket_mode'             => '0666'
    ],

    // SpamAssassin configuration
    'spamassassin'   => [
        // Enable/Disable automatic update of SpamAssassin rules
        'sa_update'                => true,

        // SpamAssassin plugins
        'plugins'                  => [
            // AWL plugin -- Normalize scores via auto-whitelist
            // See https://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Plugin_AWL.html
            'AWL'             => [
                // Enable/Disable the plugin
                'enabled'     => true,

                // SA configuration files in which the plugin must be loaded.
                'config_file' => '/etc/spamassassin/v310.pre',

                // Cronjobs
                'cronjobs'    => [
                    // Cronjob for AWL database cleanup
                    'sa-awl-clean-db' => [
                        'minute'  => '@daily',
                        'command' => 'nice -n 10 ionice -c2 -n5 perl' . __DIR__ . '/cronjobs/sa-awl-clean-db >/dev/null 2>&1'
                    ]
                ]
            ],

            // Bayes plugin -- determine spammishness using a Bayesian classifier
            // See https://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Plugin_Bayes.html
            'Bayes'           => [
                // Enable/Disable the plugin
                'enabled'          => true,

                // Setting the value to TRUE will prevent users to act on that
                // plugin through their user preferences. Plugin usage will be
                // enforced for all users.
                'enforced'         => false,

                // SA configuration file in which the plugin must be loaded.
                'config_file'      => '/etc/spamassassin/v320.pre',

                // Cronjobs
                'cronjobs'         => [
                    // Cronjob for SA-LEARN(1p)
                    'sa-bayes-sa-learn' => [
                        'minute'  => '0',
                        'hour'    => '*/12',
                        'day'     => '*',
                        'month'   => '*',
                        'dweek'   => '*',
                        'command' => 'nice -n 10 ionice -c2 -n5 perl' . __DIR__ . '/cronjobs/sa-bayes-sa-learn >/dev/null 2>&1'
                    ],
                    // Cronjob for bayes database cleanup
                    'sa-bayes-clean-db' => [
                        'minute'  => '@daily',
                        'command' => 'nice -n 10 ionice -c2 -n5 perl' . __DIR__ . '/cronjobs/sa-bayes-clean-db >/dev/null 2>&1'
                    ]
                ],

                // When set to TRUE, the site-wide bayes database is enabled.
                // This allow to share the bayesian database with all users.
                //
                // Note that setting the value to TRUE will prevent users to act
                // on some aspects of that plugin through their user preferences.
                'site_wide'        => false,

                // SA user preferences
                'user_preferences' => [
                    'use_bayes',
                    'use_bayes_rules',
                    'bayes_auto_learn'
                ]
            ],

            // DCC plugin -- perform DCC check of messages
            // See https://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Plugin_DCC.html
            //
            // You must first install DCC which is not provided by default.
            // See https://www.dcc-servers.net/dcc/INSTALL.html
            'DCC'             => [
                // Enable/Disable the plugin
                'enabled'          => false,

                // Setting the value to TRUE will prevent users to act on that
                // plugin through their user preferences. Plugin usage will be
                // enforced for all users.
                'enforced'         => false,

                // SA configuration files in which the plugin must be loaded.
                'config_file'      => '/etc/spamassassin/v310.pre',

                // Plugin SA user preferences
                'user_preferences' => [
                    'use_dcc'
                ]
            ],

            // DKIM plugin - perform DKIM verification tests
            // See https://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Plugin_DKIM.html
            //
            // You shouldn't enable this plugin if you also use the i-MSCP OpenDKIM plugin.
            'DKIM'            => [
                // Enable/Disable the plugin
                'enabled'     => false,

                // SA configuration file in which the plugin must be loaded.
                'config_file' => '/etc/spamassassin/v312.pre'
            ],

            // DecodeShortURLs 3rd-party plugin -- Expand shortened URLs
            // See https://github.com/smfreegard/DecodeShortURLs
            'DecodeShortURLs' => [
                // Enable/Disable the plugin
                'enabled'     => true,

                // SA configuration file in which the plugin must be loaded.
                'config_file' => '/etc/spamassassin/local.pre',

                // Shell commands
                'shell'      => [
                    // Shell commands to be executed upon configuration phase
                    'configure'   => [
                        <<<EOT
cp {PLUGINS_DIR}/SpamAssassin/spamassassin-plugins/DecodeShortURLs/DecodeShortURLs.pm /etc/spamassassin
cp {PLUGINS_DIR}/SpamAssassin/spamassassin-plugins/DecodeShortURLs/DecodeShortURLs.cf /etc/spamassassin
EOT
                    ],
                    // Shell command(s) to be executed upon deconfiguration phase
                    'deconfigure' => [
                        <<<EOT
rm -f /etc/spamassassin/DecodeShortURLs.pm
rm -f /etc/spamassassin/DecodeShortURLs.cf
EOT
                    ]
                ]
            ],

            // iXhash2 3rd-party plugin - perform iXhash2 check of messages
            // See http://mailfud.org/iXhash2/
            'iXhash2'         => [
                // Enable/Disable the plugin
                'enabled'     => true,

                // SA configuration file in which the plugin must be loaded.
                'config_file' => '/etc/spamassassin/local.pre',

                // Shell command(s)
                'shell'      => [
                    // Shell commands to be executed upon configuration phase
                    'configure'   => [
                        <<<EOT
cp {PLUGINS_DIR}/SpamAssassin/spamassassin-plugins/iXhash2/iXhash2.pm /etc/spamassassin
cp {PLUGINS_DIR}/SpamAssassin/spamassassin-plugins/iXhash2/iXhash2.cf /etc/spamassassin
EOT
                    ],
                    // Shell commands to be executed upon deconfiguration phase
                    'deconfigure' => [
                        <<<EOT
rm -f /etc/spamassassin/iXhash2.pm
rm -f /etc/spamassassin/iXhash2.cf
EOT
                    ]
                ]
            ],

            // Pyzor plugin -- perform Pyzor check of messages
            // See https://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Plugin_Pyzor.html
            'Pyzor'           => [
                // Enable/Disable the plugin
                'enabled'          => true,

                // Setting the value to TRUE will prevent users to act on that
                // plugin through their user preferences. Plugin usage will be
                // enforced for all users.
                'enforced'         => false,

                // SA configuration file in which the plugin must be loaded.
                'config_file'      => '/etc/spamassassin/v310.pre',

                // Shell commands
                'shell'      => [
                    // Shell commands to be executed upon configuration phase
                    'configure'   => [
                        "[ -d \"{SPAMD_HOMEDIR}/.razor\" ] || su - {SPAMD_USER} -c '/usr/bin/pyzor ping'"
                    ],
                    // Shell commands to be executed upon deconfiguration phase
                    'deconfigure' => [
                        "[ ! -d \"{SPAMD_HOMEDIR}/.pyzor\" ] || su - {SPAMD_USER} -c 'rm -R {SPAMD_HOMEDIR}/.pyzor'",
                    ]
                ],

                // SA user preferences
                'user_preferences' => [
                    'use_pyzor'
                ],

                // Required distribution packages
                'dist_packages' => [
                    'pyzor'
                ]
            ],

            // Razor2 plugin -- perform Razor check of messages
            // See https://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Plugin_Razor2.html
            'Razor2'          => [
                // Enable/Disable the plugin
                'enabled'          => true,

                // Setting the value to TRUE will prevent users to act on that
                // plugin through their user preferences. Plugin usage will be
                // enforced for all users.
                'enforced'         => false,

                // SA configuration file in which the plugin must be loaded.
                'config_file'      => '/etc/spamassassin/v310.pre',

                // Cronjobs
                'cronjobs'         => [
                    // Cronjob for Razor server discovering
                    'sa-razor-discover' => [
                        'minute'  => '@weekly',
                        'command' => 'nice -n 10 ionice -c2 -n5 perl' . __DIR__ . '/cronjobs/sa-razor-discover >/dev/null 2>&1'
                    ]
                ],

                // Shell commands
                'shell'      => [
                    // Shell commands to be executed upon configuration phase
                    'configure'   => [
                        "[ -d \"{SPAMD_HOMEDIR}/.razor\" ] || su - {SPAMD_USER} -c '/usr/bin/razor-admin -create'",
                        "[ -d \"{SPAMD_HOMEDIR}/.razor/identity\" ] || su - {SPAMD_USER} -c '/usr/bin/razor-admin -register'",
                    ],
                    // Shell commands to be executed upon deconfiguration phase
                    'deconfigure' => [
                        "[ ! -d \"{SPAMD_HOMEDIR}/.razor\" ] || su - {SPAMD_USER} -c 'rm -R {SPAMD_HOMEDIR}/.razor'",
                    ]
                ],

                // SA user preferences
                'user_preferences' => [
                    'use_razor2'
                ],

                // Required distribution packages
                'dist_packages' => [
                    'razor'
                ]
            ],

            // Rule2XSBody plugin -- speed up SpamAssassin by compiling regexps
            // See https://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Plugin_Rule2XSBody.html
            'Rule2XSBody'     => [
                // Enable/Disable the plugin
                'enabled'     => true,

                // SA configuration file in which the plugin must be loaded.
                'config_file' => '/etc/spamassassin/sa-compile.pre',

                // Required distribution packages
                'dist_packages' => [
                    'sa-compile'
                ]
            ],

            // SPF plugin -- perform SPF verification tests
            // See https://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Plugin_SPF.html
            //
            // You shouldn't enable that plugin if you have installed the i-MSCP PolicydSPF plugin
            'SPF'             => [
                // Possible values: true, false
                'enabled'     => false,

                // SA configuration file in which the plugin must be loaded.
                'config_file' => '/etc/spamassassin/init.pre',

                // Required distribution packages
                'dist_packages' => [
                    'libmail-spf-perl'
                ]
            ],

            // TextCat plugin -- language guesser
            // See https://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Plugin_TextCat.html
            'TextCat'         => [
                // Enable/Disable the plugin
                'enabled'     => true,

                // SA configuration files in which the plugin must be loaded.
                'config_file' => '/etc/spamassassin/v310.pre'
            ],

            // RBL checks (DNSEval and URIDNSBL SA plugins)
            // https://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Plugin_DNSEval.html
            // See https://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Plugin_URIDNSBL.html
            //
            // You shouldn't enable those plugins if you already use the i-MSCP PolicydWeight and/or
            // Postscreen plugins.
            'rbl_checks'      => [
                // Enable/Disable the plugins
                'enabled'          => false,

                // Setting the value to TRUE will prevent users to act on that
                // plugin through their user preferences. Plugin usage will be
                // enforced for all users.
                'enforced'         => false,

                // SA user preferences
                'user_preferences' => [
                    'skip_rbl_checks'
                ]
            ],

            //
            // Below, you can add you own SpamAssassin plugin configuration
            // definitions. See the above plugin configuration definitions to
            // learn about supported parameters.
            //
/*
            // Plugin configuration definition template
            '<plugin_name>' => [
                // Enable/Disable the plugin
                'enabled'          => true,

                // Setting the value to TRUE will prevent users to act on that
                // plugin through their user preferences. Plugin usage will be
                // enforced for all users.
                //
                // This configuration parameter is OPTIONAL. It should be
                // provided only if the plugin can be enabled/disabled on a per
                // user preference basis.
                'enforced'         => false,

                // SA configuration file in which the plugin must be loaded.
                'config_file'      => '',

                // Cronjobs
                // This configuration parameter is OPTIONAL. It should be
                // provided only if the plugin require cronjob(s).
                'cronjobs'         => [],

                // Shell commands
                // This configuration parameter is OPTIONAL. It should be
                // provided only if the plugin require specific
                // configuration/deconfiguration task(s).
                // Available placeholders:
                //  - {PLUGINS_DIR}: Replaced by i-MSCP plugin root directory
                //  - {SPAMD_USER}: Replaced by SPAMD(8p) unix user
                //  - {SPAMD_GROUP}: Replaced by SPAMD(8p) unix user group
                //  - {SPAMD_HOMEDIR}: Replaced by SPAMD(8p) unix user homedir
                'shell'      => [
                    // Shell commands to be executed upon configuration phase
                    'configure'   => [],
                    // Shell commands to be executed upon deconfiguration phase
                    'deconfigure' => []
                ],

                // SA user preferences
                // This configuration parameter is OPTIONAL. It should be
                // provided only if the plugin defines user preferences.
                'user_preferences' => [],

                // Required distribution packages
                // This configuration parameter is OPTIONAL. It should be provided
                // only if the plugin requires additional distribution packages.
                'dist_packages' => []
            ]
*/
        ],

        // 3rd-party Heinlein Support SpamAssassin ruleset
        // See https://www.heinlein-support.de/blog/news/aktuelle-spamassassin-regeln-von-heinlein-support/
        'heinlein_support_ruleset' => [
            // Enable/Disable the plugin
            'enabled'     => true,

            // Cronjob sleep timer (in seconds)
            'sleep_timer' => 600,

            // sa-update channel
            'channel'     => 'spamassassin.heinlein-support.de'
        ]
    ],

    // Roundcube configuration
    //
    // Only relevant if you use the Roundcube Webmail
    'roundcube'      => [
        'plugins' => [
            // MarkAsJunk2 Roundcube plugin
            // See https://github.com/JohnDoh/Roundcube-Plugin-Mark-as-Junk-2
            //
            // Make users able to mark their mails as SPAM|HAM for SA learning
            // Requires the SA Bayes plugin
            'markasjunk2' => [
                // Enable/Disable the plugin
                'enabled' => true
            ],

            // SAUserPrefs Roundcube plugin
            // See https://github.com/JohnDoh/Roundcube-Plugin-SpamAssassin-User-Prefs-SQL
            //
            // Make users able to customize SpamAssassin behavior through their own
            // user preferences
            'sauserprefs' => [
                // Enable/Disable the plugin
                'enabled'                   => true,

                // Protected SA user preferences
                //
                // Users won't be able to acts on preferences listed in
                // that configuration parameter.
                //
                // See the sauserprefs plugin documentation for further details.
                //
                // Possible value: array
                'sauserprefs_dont_override' => [
                    // razor1 support is officially deprecated.
                    // There is no reason to show it in plugin.
                    'use_razor1'
                ]
            ]
        ]
    ]
];

Looks good! So plugins are now in a seperate configuration array hierarchy level, able to be extended with every spamassassin plugin needed (and installed), right? But what I assume, that on upgrade to this spamass plugin version, local persistent configuration override probably has to be changed... But anyway, thank you for your efforts! Greetings from Switzerland, Mike