MDL-62248 core_block: Implement privacy API

blocks/classes/privacy/provider.php

@@ -0,0 +1,227 @@
+<?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/>.
+
+/**
+ * Data provider.
+ *
+ * @package    core_block
+ * @copyright  2018 Frédéric Massart
+ * @author     Frédéric Massart <[email protected]>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core_block\privacy;
+defined('MOODLE_INTERNAL') || die();
+
+use context;
+use context_block;
+use core_privacy\local\metadata\collection;
+use core_privacy\local\request\approved_contextlist;
+use core_privacy\local\request\transform;
+use core_privacy\local\request\writer;
+
+/**
+ * Data provider class.
+ *
+ * @package    core_block
+ * @copyright  2018 Frédéric Massart
+ * @author     Frédéric Massart <[email protected]>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class provider implements
+    \core_privacy\local\metadata\provider,
+    \core_privacy\local\request\subsystem\provider,
+    \core_privacy\local\request\user_preference_provider {
+
+    /**
+     * Returns metadata.
+     *
+     * @param collection $collection The initialised collection to add items to.
+     * @return collection A listing of user data stored through this system.
+     */
+    public static function get_metadata(collection $collection) : collection {
+        $collection->add_user_preference('blockIDhidden', 'privacy:metadata:userpref:hiddenblock');
+        $collection->add_user_preference('docked_block_instance_ID', 'privacy:metadata:userpref:dockedinstance');
+        return $collection;
+    }
+
+    /**
+     * Get the list of contexts that contain user information for the specified user.
+     *
+     * @param int $userid The user to search.
+     * @return contextlist $contextlist The contextlist containing the list of contexts used in this plugin.
+     */
+    public static function get_contexts_for_userid(int $userid) : \core_privacy\local\request\contextlist {
+        global $DB;
+        $contextlist = new \core_privacy\local\request\contextlist();
+
+        // Fetch the block instance IDs.
+        $likehidden = $DB->sql_like('name', ':hidden', false, false);
+        $likedocked = $DB->sql_like('name', ':docked', false, false);
+        $sql = "userid = :userid AND ($likehidden OR $likedocked)";
+        $params = [
+            'userid' => $userid,
+            'hidden' => 'block%hidden',
+            'docked' => 'docked_block_instance_%',
+        ];
+        $prefs = $DB->get_fieldset_select('user_preferences', 'name', $sql, $params);
+
+        $instanceids = array_unique(array_map(function($prefname) {
+            if (preg_match('/^block(\d+)hidden$/', $prefname, $matches)) {
+                return $matches[1];
+            } else if (preg_match('/^docked_block_instance_(\d+)$/', $prefname, $matches)) {
+                return $matches[1];
+            }
+            return 0;
+        }, $prefs));
+
+        // Find the context of the instances.
+        if (!empty($instanceids)) {
+            list($insql, $inparams) = $DB->get_in_or_equal($instanceids, SQL_PARAMS_NAMED);
+            $sql = "
+                SELECT ctx.id
+                  FROM {context} ctx
+                 WHERE ctx.instanceid $insql
+                   AND ctx.contextlevel = :blocklevel";
+            $params = array_merge($inparams, ['blocklevel' => CONTEXT_BLOCK]);
+            $contextlist->add_from_sql($sql, $params);
+        }
+
+        return $contextlist;
+    }
+
+    /**
+     * Export all user data for the specified user, in the specified contexts.
+     *
+     * @param approved_contextlist $contextlist The approved contexts to export information for.
+     */
+    public static function export_user_data(approved_contextlist $contextlist) {
+        global $DB;
+        $userid = $contextlist->get_user()->id;
+
+        // Extract the block instance IDs.
+        $instanceids = array_reduce($contextlist->get_contexts(), function($carry, $context) {
+            if ($context->contextlevel == CONTEXT_BLOCK) {
+                $carry[] = $context->instanceid;
+            }
+            return $carry;
+        }, []);
+        if (empty($instanceids)) {
+            return;
+        }
+
+        // Query the blocks and their preferences.
+        list($insql, $inparams) = $DB->get_in_or_equal($instanceids, SQL_PARAMS_NAMED);
+        $hiddenkey = $DB->sql_concat("'block'", 'bi.id', "'hidden'");
+        $dockedkey = $DB->sql_concat("'docked_block_instance_'", 'bi.id');
+        $sql = "
+            SELECT bi.id, h.value AS prefhidden, d.value AS prefdocked
+              FROM {block_instances} bi
+         LEFT JOIN {user_preferences} h
+                ON h.userid = :userid1
+               AND h.name = $hiddenkey
+         LEFT JOIN {user_preferences} d
+                ON d.userid = :userid2
+               AND d.name = $dockedkey
+             WHERE bi.id $insql
+               AND (h.id IS NOT NULL
+                OR d.id IS NOT NULL)";
+        $params = array_merge($inparams, [
+            'userid1' => $userid,
+            'userid2' => $userid,
+        ]);
+
+        // Export all the things.
+        $dockedstr = get_string('privacy:request:blockisdocked', 'core_block');
+        $hiddenstr = get_string('privacy:request:blockishidden', 'core_block');
+        $recordset = $DB->get_recordset_sql($sql, $params);
+        foreach ($recordset as $record) {
+            $context = context_block::instance($record->id);
+            if ($record->prefdocked !== null) {
+                writer::with_context($context)->export_user_preference(
+                    'core_block',
+                    'block_is_docked',
+                    transform::yesno($record->prefdocked),
+                    $dockedstr
+                );
+            }
+            if ($record->prefhidden !== null) {
+                writer::with_context($context)->export_user_preference(
+                    'core_block',
+                    'block_is_hidden',
+                    transform::yesno($record->prefhidden),
+                    $hiddenstr
+                );
+            }
+        }
+        $recordset->close();
+    }
+
+    /**
+     * Export all user preferences for the plugin.
+     *
+     * @param int $userid The userid of the user whose data is to be exported.
+     */
+    public static function export_user_preferences(int $userid) {
+      // Our preferences aren't site-wide so they are exported in export_user_data.
+    }
+
+    /**
+     * Delete all data for all users in the specified context.
+     *
+     * @param context $context The specific context to delete data for.
+     */
+    public static function delete_data_for_all_users_in_context(context $context) {
+        global $DB;
+        if ($context->contextlevel != CONTEXT_BLOCK) {
+            return;
+        }
+
+        // Delete the user preferences.
+        $instanceid = $context->instanceid;
+        $DB->delete_records_list('user_preferences', 'name', [
+            "block{$instanceid}hidden",
+            "docked_block_instance_{$instanceid}"
+        ]);
+    }
+
+    /**
+     * Delete all user data for the specified user, in the specified contexts.
+     *
+     * @param approved_contextlist $contextlist The approved contexts and user information to delete information for.
+     */
+    public static function delete_data_for_user(approved_contextlist $contextlist) {
+        global $DB;
+        $userid = $contextlist->get_user()->id;
+        $prefnames = array_reduce($contextlist->get_contexts(), function($carry, $context) {
+            if ($context->contextlevel == CONTEXT_BLOCK) {
+                $carry[] = "block{$context->instanceid}hidden";
+                $carry[] = "docked_block_instance_{$context->instanceid}";
+            }
+            return $carry;
+        }, []);
+
+        if (empty($prefnames)) {
+            return;
+        }
+
+        list($insql, $inparams) = $DB->get_in_or_equal($prefnames, SQL_PARAMS_NAMED);
+        $sql = "userid = :userid AND name $insql";
+        $params = array_merge($inparams, ['userid' => $userid]);
+        $DB->delete_records_select('user_preferences', $sql, $params);
+    }
+
+}