Your IP : 18.220.110.45
<?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/>.
/**
* Class containing utility methods for dataformats
*
* @package core
* @copyright 2020 Paul Holden <paulh@moodle.com>
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
namespace core;
use coding_exception;
use core_php_time_limit;
use stored_file;
/**
* Dataformat utility class
*
* @package core
* @copyright 2020 Paul Holden <paulh@moodle.com>
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
class dataformat {
/**
* Return an instance of a dataformat writer from given dataformat type
*
* @param string $dataformat
* @return dataformat\base
* @throws coding_exception
*/
protected static function get_format_instance(string $dataformat): \core\dataformat\base {
$classname = 'dataformat_' . $dataformat . '\writer';
if (!class_exists($classname)) {
throw new coding_exception('Invalid dataformat', $dataformat);
}
return new $classname();
}
/**
* Sends a formatted data file to the browser
*
* @param string $filename
* @param string $dataformat
* @param array $columns
* @param Iterable $iterator
* @param callable|null $callback Optional callback method to apply to each record prior to writing, which accepts two
* parameters as such: function($record, bool $supportshtml) returning formatted record
* @throws coding_exception
*/
public static function download_data(string $filename, string $dataformat, array $columns, Iterable $iterator,
callable $callback = null): void {
if (ob_get_length()) {
throw new coding_exception('Output can not be buffered before calling download_data()');
}
$format = self::get_format_instance($dataformat);
// The data format export could take a while to generate.
core_php_time_limit::raise();
// Close the session so that the users other tabs in the same session are not blocked.
\core\session\manager::write_close();
// If this file was requested from a form, then mark download as complete (before sending headers).
\core_form\util::form_download_complete();
$format->set_filename($filename);
$format->send_http_headers();
$format->start_output();
$format->start_sheet($columns);
$rownum = 0;
foreach ($iterator as $row) {
if (is_callable($callback)) {
$row = $callback($row, $format->supports_html());
}
if ($row === null) {
continue;
}
$format->write_record($row, $rownum++);
}
$format->close_sheet($columns);
$format->close_output();
}
/**
* Writes a formatted data file with specified filename
*
* @param string $filename
* @param string $dataformat
* @param array $columns
* @param Iterable $iterator
* @param callable|null $callback
* @return string Complete path to the file on disk
*/
public static function write_data(string $filename, string $dataformat, array $columns, Iterable $iterator,
callable $callback = null): string {
$format = self::get_format_instance($dataformat);
// The data format export could take a while to generate.
core_php_time_limit::raise();
// Close the session so that the users other tabs in the same session are not blocked.
\core\session\manager::write_close();
$filepath = make_request_directory() . '/' . $filename . $format->get_extension();
$format->set_filepath($filepath);
$format->start_output_to_file();
$format->start_sheet($columns);
$rownum = 0;
foreach ($iterator as $row) {
if (is_callable($callback)) {
$row = $callback($row, $format->supports_html());
}
if ($row === null) {
continue;
}
$format->write_record($row, $rownum++);
}
$format->close_sheet($columns);
$format->close_output_to_file();
return $filepath;
}
/**
* Writes a formatted data file to file storage
*
* @param array $filerecord File record for storage, 'filename' extension should be omitted as it's added by the dataformat
* @param string $dataformat
* @param array $columns
* @param Iterable $iterator Iterable set of records to write
* @param callable|null $callback Optional callback method to apply to each record prior to writing
* @return stored_file
*/
public static function write_data_to_filearea(array $filerecord, string $dataformat, array $columns, Iterable $iterator,
callable $callback = null): stored_file {
$filepath = self::write_data($filerecord['filename'], $dataformat, $columns, $iterator, $callback);
// Update filename of returned file record.
$filerecord['filename'] = basename($filepath);
return get_file_storage()->create_file_from_pathname($filerecord, $filepath);
}
}