Create semester custom field type

classes/data_controller.php

+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Semester customfield data controller
+ *
+ * Semesters are encoded as YYYYS, where YYYY is the year when the semester begins and
+ * S is 0 = summersemester and 1 = wintersemester. So 20191 stands for WiSe 2019/2020.
+ * Exception: 0 stands for semesterindepentent.
+ *
+ * @package   customfield_semester
+ * @copyright 2020 Justus Dieckmann WWU
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace customfield_semester;
+
+use DateTime;
+
+defined('MOODLE_INTERNAL') || die;
+
+/**
+ * Semester customfield data controller
+ *
+ * @package   customfield_semester
+ * @copyright 2020 Justus Dieckmann WWU
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class data_controller extends \core_customfield\data_controller {
+
+    /**
+     * Return the name of the field where the information is stored
+     *
+     * @return string
+     */
+    public function datafield(): string {
+        return 'intvalue';
+    }
+
+    /**
+     * Returns the default value as it would be stored in the database (not in human-readable format).
+     *
+     * @return mixed
+     */
+    public function get_default_value() {
+        $defaultmonthsintofuture = $this->get_field()->get_configdata_property('defaultmonthsintofuture');
+        return self::get_semester_for_datetime(new DateTime("+$defaultmonthsintofuture months"));
+    }
+
+    /**
+     * Add fields for editing a textarea field.
+     *
+     * @param \MoodleQuickForm $mform
+     */
+    public function instance_form_definition(\MoodleQuickForm $mform) {
+        $field = $this->get_field();
+        $formattedoptions = array(
+                0 => get_string('semesterindependent', 'customfield_semester')
+        );
+        $showmonthsintofuture = $this->get_field()->get_configdata_property('showmonthsintofuture');
+        $endtime = new DateTime("+$showmonthsintofuture months");
+        $endkey = self::get_semester_for_datetime($endtime);
+        $endyear = $endkey / 10;
+        $endsemester = $endkey % 10;
+
+        $beginofsemesters = $this->get_field()->get_configdata_property('beginofsemesters');
+        for ($year = $beginofsemesters; $year <= $endyear; $year++) {
+            $formattedoptions[$year * 10] = get_string('summersemester', 'customfield_semester') . ' ' . $year;
+
+            if ($year == $endyear && $endsemester == 0) {
+                break;
+            }
+
+            $formattedoptions[$year * 10 + 1] =
+                    get_string('wintersemester', 'customfield_semester') . ' ' . $year . '/' . ($year + 1);
+        }
+
+        $elementname = $this->get_form_element_name();
+        $mform->addElement('select', $elementname, $this->get_field()->get_formatted_name(), $formattedoptions);
+
+        if ($field->get_configdata_property('required')) {
+            $mform->addRule($elementname, null, 'required', null, 'client');
+        }
+    }
+
+    /**
+     * Validates data for this field.
+     *
+     * @param array $data
+     * @param array $files
+     * @return array
+     */
+    public function instance_form_validation(array $data, array $files): array {
+        $errors = parent::instance_form_validation($data, $files);
+        if ($this->get_field()->get_configdata_property('required')) {
+            // Standard required rule does not work on select element.
+            $elementname = $this->get_form_element_name();
+            if (empty($data[$elementname])) {
+                $errors[$elementname] = get_string('err_required', 'form');
+            }
+        }
+        return $errors;
+    }
+
+    /**
+     * Returns value in a human-readable format
+     *
+     * @return mixed|null value or null if empty
+     */
+    public function export_value() {
+        $value = $this->get_value();
+        return self::get_name_for_semester($value);
+    }
+
+    /**
+     * Returns the human readable Semester name for a semesterid.
+     *
+     * @param int $value the semesterid (YYYYS as descibed at the top of the file).
+     * @return string|null The human readable semester name
+     */
+    public static function get_name_for_semester(int $value) {
+        if ($value === 0) {
+            return get_string('semesterindependent', 'customfield_semester');
+        } else if ($value == null) {
+            return null;
+        } else {
+            $year = $value / 10;
+            $semester = $value % 10;
+            if ($semester === 0) {
+                return get_string('summersemester', 'customfield_semester') . ' ' . $year;
+            } else {
+                return get_string('wintersemester', 'customfield_semester') . ' ' . $year . '/' . ($year + 1);
+            }
+        }
+    }
+
+    public static function get_semester_for_datetime(DateTime $datetime): int {
+        $year = (int) $datetime->format('Y');
+        $month = (int) $datetime->format('m');
+        if ($month < 4) {
+            $year--;
+            $semester = 1;
+        } else if ($month < 10) {
+            $semester = 0;
+        } else {
+            $semester = 1;
+        }
+        return $year * 10 + $semester;
+    }
+}

classes/field_controller.php

+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Semester customfield field controller
+ *
+ * @package   customfield_semester
+ * @copyright 2020 Justus Dieckmann WWU
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace customfield_semester;
+
+defined('MOODLE_INTERNAL') || die;
+
+/**
+ * Semester customfield field controller
+ *
+ * @package   customfield_semester
+ * @copyright 2020 Justus Dieckmann WWU
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class field_controller extends \core_customfield\field_controller {
+    /**
+     * Plugin type
+     */
+    const TYPE = 'semester';
+
+    /**
+     * Add fields for editing a select field.
+     *
+     * @param \MoodleQuickForm $mform
+     */
+    public function config_form_definition(\MoodleQuickForm $mform) {
+        $config = $this->get('configdata');
+
+        $mform->addElement('header', 'header_specificsettings',
+                get_string('specificsettings', 'customfield_semester'));
+        $mform->setExpanded('header_specificsettings', true);
+
+        $mform->addElement('text', 'configdata[showmonthsintofuture]',
+                get_string('showmonthsintofuture', 'customfield_semester'));
+        $mform->setType('configdata[showmonthsintofuture]', PARAM_INT);
+        if (!$config) {
+            $mform->setDefault('configdata[showmonthsintofuture]', 6);
+        }
+        $mform->addRule('configdata[showmonthsintofuture]', null, 'numeric', null, 'client');
+
+        $mform->addElement('text', 'configdata[defaultmonthsintofuture]',
+                get_string('defaultmonthsintofuture', 'customfield_semester'));
+        $mform->setType('configdata[defaultmonthsintofuture]', PARAM_INT);
+        if (!$config) {
+            $mform->setDefault('configdata[defaultmonthsintofuture]', 3);
+        }
+        $mform->addRule('configdata[defaultmonthsintofuture]', null, 'numeric', null, 'client');
+
+        $mform->addElement('text', 'configdata[beginofsemesters]',
+                get_string('beginofsemesters', 'customfield_semester'));
+        $mform->setType('configdata[beginofsemesters]', PARAM_INT);
+        if (!$config) {
+            $mform->setDefault('configdata[beginofsemesters]', 2007);
+        }
+        $mform->addRule('configdata[beginofsemesters]', null, 'numeric', null, 'client');
+    }
+
+    /**
+     * Does this custom field type support being used as part of the block_myoverview
+     * custom field grouping?
+     * @return bool
+     */
+    public function supports_course_grouping(): bool {
+        return true;
+    }
+
+    /**
+     * If this field supports course grouping, then this function needs overriding to
+     * return the formatted values for this.
+     * @param array $values the used values that need formatting
+     * @return array
+     */
+    public function course_grouping_format_values($values): array {
+        $ret = [];
+        foreach ($values as $value) {
+            $name = data_controller::get_name_for_semester($value);
+            if ($name) {
+                $ret[$value] = $name;
+            }
+        }
+        return $ret;
+    }
+}

classes/privacy/provider.php

+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.
+/**
+ * Privacy Subsystem implementation for customfield_semester.
+ *
+ * @package    customfield_semester
+ * @copyright  2020 Justus Dieckmann
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace customfield_semester\privacy;
+
+use core_customfield\data_controller;
+use core_customfield\privacy\customfield_provider;
+use core_privacy\local\request\writer;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Privacy Subsystem for customfield_semester implementing null_provider.
+ *
+ * @copyright  2020 Justus Dieckmann
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class provider implements \core_privacy\local\metadata\null_provider, customfield_provider {
+
+    /**
+     * Get the language string identifier with the component's language
+     * file to explain why this plugin stores no data.
+     *
+     * @return  string
+     */
+    public static function get_reason() : string {
+        return 'privacy:metadata';
+    }
+
+    /**
+     * Preprocesses data object that is going to be exported
+     *
+     * @param data_controller $data
+     * @param \stdClass $exportdata
+     * @param array $subcontext
+     */
+    public static function export_customfield_data(data_controller $data, \stdClass $exportdata, array $subcontext) {
+        $context = $data->get_context();
+        $exportdata->value = $data->export_value();
+        writer::with_context($context)
+            ->export_data($subcontext, $exportdata);
+    }
+
+    /**
+     * Allows plugins to delete everything they store related to the data (usually files)
+     *
+     * @param string $dataidstest
+     * @param array $params
+     * @param array $contextids
+     * @return mixed|void
+     */
+    public static function before_delete_data(string $dataidstest, array $params, array $contextids) {
+    }
+
+    /**
+     * Allows plugins to delete everything they store related to the field configuration (usually files)
+     *
+     * @param string $fieldidstest
+     * @param array $params
+     * @param array $contextids
+     */
+    public static function before_delete_fields(string $fieldidstest, array $params, array $contextids) {
+    }
+}

lang/de/customfield_semester.php

+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Customfield semester field plugin strings
+ *
+ * @package   customfield_semester
+ * @copyright 2020 Justus Dieckmann WWU
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+$string['pluginname'] = 'Semesterfeld';
+$string['semesterindependent'] = 'Semesterunabhängig';
+$string['summersemester'] = 'SoSe';
+$string['wintersemester'] = 'WiSe';
+$string['specificsettings'] = 'Einstellungen für das Semesterfeld';
+$string['showmonthsintofuture'] = 'Ein Semester ist auswählbar, wenn es in weniger als X Monaten beginnt.';
+$string['defaultmonthsintofuture'] = 'Standard ist das Semester in X Monaten.';
+$string['beginofsemesters'] = 'Das Jahr, in dem die Liste der Semester anfängt.';

lang/en/customfield_semester.php

+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Customfield semester field plugin strings
+ *
+ * @package   customfield_semester
+ * @copyright 2020 Justus Dieckmann WWU
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+$string['pluginname'] = 'Semester field';
+$string['semesterindependent'] = 'Semester independent';
+$string['summersemester'] = 'SoSe';
+$string['wintersemester'] = 'WiSe';
+$string['specificsettings'] = 'Semester field settings';
+$string['showmonthsintofuture'] = 'A semester will be selectable, if it begins in less than X months.';
+$string['defaultmonthsintofuture'] = 'The default option is the semester in X months.';
+$string['beginofsemesters'] = 'The year, the list of semesters begins in.';

version.php

+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Customfield Semester Type
+ *
+ * @package   customfield_semester
+ * @copyright 2020 Justus Dieckmann WWU
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+$plugin->component = 'customfield_semester';
+$plugin->version   = 2020041301;
+$plugin->requires  = 2019111800;