fix: change abort_if to abort, add comments and simplify

- abort step, condition not required (defaults to true)
- abort step, simplify conditions when to abort
- add more logging to the abort step

classes/local/step/abort_trait.php

@@ -0,0 +1,79 @@
+<?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/>.
+
+/**
+ * Abort Step ..Trait
+ *
+ * This trait allows both flow/connector implementations to share core
+ * functionality. This should be moved to the "main" step type in an ideal
+ * world, and live there directly instead, but will need to be done as such
+ * until support for dual steps are fully supported.
+ *
+ * @package    tool_dataflows
+ * @author     Kevin Pham <[email protected]>
+ * @copyright  Catalyst IT, 2022
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace tool_dataflows\local\step;
+
+trait abort_trait {
+
+    /**
+     * Executes the step, aborting the whole dataflow.
+     *
+     * @param mixed|null $input
+     * @return mixed
+     */
+    public function execute($input = null) {
+        $config = $this->get_config();
+
+        // If a condition was set, it should not abort if the result is false. be evaluated and abort if 'true'.
+        if ($config->condition === false) {
+            return $input;
+        }
+
+        // If the condition was set, print out the results of the expression so it's obvious what it had evaluated to.
+        if ($config->condition !== '') {
+            $rawconfig = $this->get_raw_config();
+            $strresult = var_export($config->condition, true);
+            $this->log("Aborting dataflow due to the expression returning '{$strresult}': {$rawconfig->condition}");
+        }
+
+        // By default, it should abort the step.
+        throw new \Exception('Aborting');
+    }
+
+    /**
+     * Return the definition of the fields available in this form.
+     *
+     * @return array
+     */
+    public static function form_define_fields(): array {
+        return [
+            'condition' => ['type' => PARAM_TEXT, 'required' => false],
+        ];
+    }
+
+    /**
+     * Custom form inputs
+     *
+     * @param \MoodleQuickForm $mform
+     */
+    public function form_add_custom_inputs(\MoodleQuickForm &$mform) {
+        $mform->addElement('text', 'config_condition', get_string('connector_abort:condition', 'tool_dataflows'));
+    }
+}

classes/local/step/base_step.php

@@ -662,6 +662,17 @@ protected function get_config(): \stdClass {
         return $this->stepdef->config;
     }
 
+    /**
+     * Get the step's (definition) raw config
+     *
+     * Helper method to reduce the complexity when authoring step types.
+     *
+     * @return  \stdClass configuration object
+     */
+    protected function get_raw_config(): \stdClass {
+        return $this->stepdef->get_raw_config();
+    }
+
     /**
      * Returns whether the engine's run is dry
      *

classes/local/step/connector_abort.php

@@ -0,0 +1,35 @@
+<?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;
+
+/**
+ * 'Abort if' step
+ *
+ * @package    tool_dataflows
+ * @author     Kevin Pham <[email protected]>
+ * @copyright  Catalyst IT, 2022
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class connector_abort extends connector_step {
+    use abort_trait;
+
+    /** @var int[] number of output flows (min, max). */
+    protected $outputflows = [0, 1];
+
+    /** @var int[] number of output connectors (min, max) */
+    protected $outputconnectors = [0, 1];
+}

lang/en/tool_dataflows.php

@@ -108,6 +108,7 @@
 $string['strftimedatetimeaccurate'] = '%d %B %Y, %I:%M:%S %p';
 
 // Step names.
+$string['step_name_connector_abort'] = 'Abort connector';
 $string['step_name_connector_curl'] = 'Curl connector';
 $string['step_name_connector_debugging'] = 'Debugging connector';
 $string['step_name_connector_email'] = 'Email notification';
@@ -383,6 +384,9 @@
 $string['connector_wait:timesec'] = 'Time in seconds';
 $string['connector_wait:not_integer'] = 'Wait time value must evaluate to a positive integer (had "{$a}").';
 
+// Abort If.
+$string['connector_abort:condition'] = 'Condition';
+
 // Flow Web service.
 $string['flow_web_service:webservice'] = 'Web service';
 $string['flow_web_service:webservice_help'] = 'Web service name to call ie: <code>core_user_create_users</code>';

lib.php

@@ -48,6 +48,7 @@ function tool_dataflows_after_config() {
  */
 function tool_dataflows_step_types() {
     return [
+        new step\connector_abort,
         new step\connector_curl,
         new step\connector_debugging,
         new step\connector_debug_file_display,