feat: Issue 754 : Json flow / split json_trait

classes/local/step/flow_json.php

@@ -0,0 +1,43 @@
+<?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/>.
+
+namespace tool_dataflows\local\step;
+
+use tool_dataflows\local\execution\iterators\dataflow_iterator;
+use tool_dataflows\local\execution\iterators\iterator;
+
+/**
+ *
+ * JSON flow step type
+ *
+ * @package    tool_dataflows
+ * @author     Ghaly Marc-Alexandre <[email protected]>
+ * @copyright  Catalyst IT, 2023
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class flow_json extends flow_step {
+    /** @var string sort order descending key */
+    const DESC = 'desc';
+
+    /** @var string sort order ascending key */
+    const ASC = 'asc';
+
+    use json_trait;
+
+    public function execute($input = null) {
+        return $this->parse_json();
+    }
+}

classes/local/step/json_trait.php

@@ -0,0 +1,207 @@
+<?php
+// This file is part of Moodle - https://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/>.
+
+namespace tool_dataflows\local\step;
+
+use html_writer;
+use Symfony\Component\ExpressionLanguage\ExpressionLanguage;
+use tool_dataflows\helper;
+use tool_dataflows\local\execution\iterators\iterator;
+use tool_dataflows\local\execution\iterators\dataflow_iterator;
+
+/**
+ * JSON trait
+ *
+ * @package   tool_dataflows
+ * @author    Peter Sistrom <[email protected]>
+ * @author    Ghaly Marc-Alexandre <[email protected]>
+ * @copyright 2023, Catalyst IT
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+trait json_trait {
+    /**
+     * Return the definition of the fields available in this form.
+     *
+     * @return array
+     */
+    public static function form_define_fields(): array {
+        return [
+            'pathtojson' => ['type' => PARAM_TEXT],
+            'arrayexpression' => ['type' => PARAM_TEXT],
+            'arraysortexpression' => ['type' => PARAM_TEXT],
+            'sortorder' => ['type' => PARAM_TEXT],
+        ];
+    }
+
+    /**
+     * Parses json string to php array.
+     *
+     * @return mixed
+     * @throws \moodle_exception
+     */
+    protected function parse_json() {
+        $config = $this->get_variables()->get('config');
+        $jsonstring = $this->get_json_string($config->pathtojson);
+
+        $decodedjson = json_decode($jsonstring);
+        if (is_null($decodedjson)) {
+            throw new \moodle_exception(get_string('reader_json:failed_to_decode_json', 'tool_dataflows', $config->pathtojson));
+        }
+
+        $arrayexpression = $config->arrayexpression;
+        $expressionlanguage = new ExpressionLanguage();
+        $returnarray = $expressionlanguage->evaluate(
+            $arrayexpression != '' ? 'data.'.$arrayexpression : 'data',
+            ['data' => $decodedjson]
+        );
+
+        if (is_null($returnarray)) {
+            throw new \moodle_exception(get_string('reader_json:failed_to_fetch_array',
+                'tool_dataflows', $config->arrayexpression));
+        }
+
+        $sortbyexpression = $config->arraysortexpression;
+
+        // Sort the parsed array if required.
+        if ($sortbyexpression !== '') {
+            return $this->sort_by_config_value($returnarray, $sortbyexpression);
+        }
+
+        return $returnarray;
+    }
+
+    /**
+     * Parses stream to json string.
+     *
+     * @param string $path
+     * @return string json
+     * @throws \moodle_exception
+     */
+    protected function get_json_string(string $path): string {
+        $jsonstring = file_get_contents($this->enginestep->engine->resolve_path($path));
+        if ($jsonstring === false) {
+            $this->enginestep->log(error_get_last()['message']);
+            throw new \moodle_exception(get_string('reader_json:failed_to_open_file', 'tool_dataflows', $path));
+        }
+
+        return $jsonstring;
+    }
+
+    /**
+     * Sort array by config value.
+     *
+     * @param array $array
+     * @param string $sortbyexpression
+     */
+    public function sort_by_config_value(array $array, string $sortbyexpression): array {
+        $expressionlanguage = new ExpressionLanguage();
+        usort($array, function ($a, $b) use ($sortbyexpression, $expressionlanguage) {
+            $a = $expressionlanguage->evaluate(
+                'data.'.$sortbyexpression,
+                ['data' => $a]
+            );
+            $b = $expressionlanguage->evaluate(
+                'data.'.$sortbyexpression,
+                ['data' => $b]
+            );
+            return strnatcasecmp($a, $b) * $this->get_sort_order_direction();
+        });
+        return $array;
+    }
+
+    /**
+     * Converts the sort order to an int used to flip the default order
+     *
+     * This returns 1 for default sort ASC order and -1 for DESC order
+     *
+     * @return  int
+     */
+    public function get_sort_order_direction() {
+        $sortorder = $this->get_variables()->get('config.sortorder');
+        if ($sortorder === self::DESC) {
+            return -1;
+        }
+
+        return 1;
+    }
+
+    /**
+     * Validate the configuration settings.
+     *
+     * @param object $config
+     * @return true|\lang_string[] true if valid, an array of errors otherwise
+     */
+    public function validate_config($config) {
+        $errors = [];
+        if (!isset($config->pathtojson)) {
+            $errors['config_pathtojson'] = get_string('config_field_missing', 'tool_dataflows', 'pathtojson', true);
+        } else {
+            $error = helper::path_validate($config->pathtojson);
+            if ($error !== true) {
+                $errors['config_pathtojson'] = $error;
+            }
+        }
+        return empty($errors) ? true : $errors;
+    }
+
+    /**
+     * Allows each step type to determine a list of optional/required form
+     * inputs for their configuration
+     *
+     * It's recommended you prefix the additional config related fields to avoid
+     * conflicts with any existing fields.
+     *
+     * @param \MoodleQuickForm $mform
+     */
+    public function form_add_custom_inputs(\MoodleQuickForm &$mform) {
+        // JSON array source.
+        $mform->addElement('text', 'config_pathtojson', get_string('reader_json:pathtojson', 'tool_dataflows'));
+        $mform->addElement('static', 'config_json_path_help', '',  get_string('path_help', 'tool_dataflows').
+            \html_writer::nonempty_tag('pre', get_string('path_help_examples', 'tool_dataflows')));
+
+        // Array iterator value.
+        $arrayexample = (object) [
+            'data' => (object) [
+                'list' => [
+                    'users' => [
+                        ['id' => '1', 'userdetails' => ['firstname' => 'Bob', 'lastname' => 'Smith', 'name' => 'Name1']],
+                    ],
+                ],
+            ],
+            'modified' => [1654058940],
+            'errors' => [],
+        ];
+        $jsonexample = html_writer::empty_tag('br').
+            html_writer::nonempty_tag('pre', json_encode($arrayexample, JSON_PRETTY_PRINT));
+        $expression = html_writer::nonempty_tag('code', 'data.list.users');
+
+        $mform->addElement('text', 'config_arrayexpression', get_string('reader_json:arrayexpression', 'tool_dataflows'));
+        $mform->addElement('static', 'config_arrayexpression_help', '',
+            get_string('reader_json:arrayexpression_help', 'tool_dataflows',
+                ['jsonexample' => $jsonexample, 'expression' => $expression]));
+
+        // JSON array sort by.
+        $mform->addElement('text', 'config_arraysortexpression', get_string('reader_json:arraysortexpression', 'tool_dataflows'));
+        $mform->addElement('static', 'config_arraysortexpression_help', '',
+            get_string('reader_json:arraysortexpression_help', 'tool_dataflows',
+                html_writer::nonempty_tag('code', 'userdetails.firstname')));
+
+        // JSON array sort order (ASC, DESC).
+        $mform->addElement('select', 'config_sortorder', get_string('reader_json:sortorder', 'tool_dataflows'),
+            ['asc' => get_string(self::ASC), 'desc' => get_string(self::DESC)]);
+        $mform->addElement('static', 'config_sortorder_help', '', get_string('reader_json:sortorder_help', 'tool_dataflows'));
+    }
+}