moodle/backup/util/converter/base_converter.class.php

<?php
/**
 * Base Abstract Converter
 *
 * @throws backup_exception|Exception|null
 */
abstract class base_converter {

    protected $id;
    protected $tempdir;
    protected $convertdir;

    // do we want absolute path instead of tempdir?
    // Do we need to create a new tempdir to convert into?  EG: target...
    public function __construct($tempdir) {
        $this->tempdir    = $tempdir;
        $this->convertdir = $this->tempdir.'_'.$this->get_name();
        $this->id         = convert_helper::generate_id($this->convertdir);
        $this->init();
    }

    public function init() {
    }

    public function get_id() {
        return $this->id;
    }

    public function get_name() {
        return array_shift(explode('_', get_class($this)));
    }

    public function get_convertdir() {
        global $CFG;

        return "$CFG->dataroot/temp/backup/$this->convertdir";
    }

    public function get_tempdir() {
        global $CFG;

        return "$CFG->dataroot/temp/backup/$this->tempdir";
    }

    public function delete_convertdir() {
        fulldelete($this->get_convertdir());
    }

    public function create_convertdir() {
        $this->delete_convertdir();
        make_upload_directory($this->get_convertdir());
    }

    public function replace_tempdir() {
        fulldelete($this->get_tempdir());

        if (!rename($this->get_convertdir(), $this->get_tempdir())) {
            throw new backup_exception('failedmoveconvertedintoplace'); // @todo Define this string
        }
    }

    /**
     * @abstract
     * @return boolean
     */
    abstract public function can_convert();

    // Kicks things off
    public function convert() {

        $e = NULL;

        try {
            $this->create_convertdir();
            $this->execute();
            $this->replace_tempdir();
        } catch (Exception $e) {
        }
        // Do cleanup...
        $this->destroy();

        if ($e instanceof Exception) {
            throw $e;
        }
    }

    abstract public function execute();

    public function destroy() {
        $this->delete_convertdir();
    }
}