MDL-59630 analytics: mlbackend model directories deletion

analytics/classes/predictor.php

@@ -41,4 +41,37 @@ interface predictor {
      * @return bool
      */
     public function is_ready();
+
+    /**
+     * Delete all stored information of the current model id.
+     *
+     * This method is called when there are important changes to a model,
+     * all previous training algorithms using that version of the model
+     * should be deleted.
+     *
+     * In case you want to perform extra security measures before deleting
+     * a directory you can check that $modelversionoutputdir subdirectories
+     * can only be named 'execution', 'evaluation' or 'testing'.
+     *
+     * @param string $uniqueid The site model unique id string
+     * @param string $modelversionoutputdir The output dir of this model version
+     * @return null
+     */
+    public function clear_model($uniqueid, $modelversionoutputdir);
+
+    /**
+     * Delete the output directory.
+     *
+     * This method is called when a model is completely deleted.
+     *
+     * In case you want to perform extra security measures before deleting
+     * a directory you can check that the subdirectories are timestamps
+     * (the model version) and each of this subdirectories' subdirectories
+     * can only be named 'execution', 'evaluation' or 'testing'.
+     *
+     * @param string $modeloutputdir The model directory id (parent of all model versions subdirectories).
+     * @return null
+     */
+    public function delete_output_dir($modeloutputdir);
+
 }