2 // This file is part of Moodle - http://moodle.org/
4 // Moodle is free software: you can redistribute it and/or modify
5 // it under the terms of the GNU General Public License as published by
6 // the Free Software Foundation, either version 3 of the License, or
7 // (at your option) any later version.
9 // Moodle is distributed in the hope that it will be useful,
10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 // GNU General Public License for more details.
14 // You should have received a copy of the GNU General Public License
15 // along with Moodle. If not, see <http://www.gnu.org/licenses/>.
18 * Class containing utility methods for dataformats
21 * @copyright 2020 Paul Holden <paulh@moodle.com>
22 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
28 use core_php_time_limit
;
32 * Dataformat utility class
35 * @copyright 2020 Paul Holden <paulh@moodle.com>
36 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
41 * Return an instance of a dataformat writer from given dataformat type
43 * @param string $dataformat
44 * @return dataformat\base
45 * @throws coding_exception
47 protected static function get_format_instance(string $dataformat): \core\dataformat\base
{
48 $classname = 'dataformat_' . $dataformat . '\writer';
49 if (!class_exists($classname)) {
50 throw new coding_exception('Invalid dataformat', $dataformat);
53 return new $classname();
57 * Sends a formatted data file to the browser
59 * @param string $filename
60 * @param string $dataformat
61 * @param array $columns
62 * @param Iterable $iterator
63 * @param callable|null $callback Optional callback method to apply to each record prior to writing, which accepts two
64 * parameters as such: function($record, bool $supportshtml) returning formatted record
65 * @throws coding_exception
67 public static function download_data(string $filename, string $dataformat, array $columns, Iterable
$iterator,
68 callable
$callback = null): void
{
70 if (ob_get_length()) {
71 throw new coding_exception('Output can not be buffered before calling download_data()');
74 $format = self
::get_format_instance($dataformat);
76 // The data format export could take a while to generate.
77 core_php_time_limit
::raise();
79 // Close the session so that the users other tabs in the same session are not blocked.
80 \core\session\manager
::write_close();
82 // If this file was requested from a form, then mark download as complete (before sending headers).
83 \core_form\util
::form_download_complete();
85 $format->set_filename($filename);
86 $format->send_http_headers();
88 $format->start_output();
89 $format->start_sheet($columns);
92 foreach ($iterator as $row) {
93 if (is_callable($callback)) {
94 $row = $callback($row, $format->supports_html());
99 $format->write_record($row, $rownum++
);
102 $format->close_sheet($columns);
103 $format->close_output();
107 * Writes a formatted data file with specified filename
109 * @param string $filename
110 * @param string $dataformat
111 * @param array $columns
112 * @param Iterable $iterator
113 * @param callable|null $callback
114 * @return string Complete path to the file on disk
116 public static function write_data(string $filename, string $dataformat, array $columns, Iterable
$iterator,
117 callable
$callback = null): string {
119 $format = self
::get_format_instance($dataformat);
121 // The data format export could take a while to generate.
122 core_php_time_limit
::raise();
124 // Close the session so that the users other tabs in the same session are not blocked.
125 \core\session\manager
::write_close();
127 $filepath = make_request_directory() . '/' . $filename . $format->get_extension();
128 $format->set_filepath($filepath);
130 $format->start_output_to_file();
131 $format->start_sheet($columns);
134 foreach ($iterator as $row) {
135 if (is_callable($callback)) {
136 $row = $callback($row, $format->supports_html());
141 $format->write_record($row, $rownum++
);
144 $format->close_sheet($columns);
145 $format->close_output_to_file();
151 * Writes a formatted data file to file storage
153 * @param array $filerecord File record for storage, 'filename' extension should be omitted as it's added by the dataformat
154 * @param string $dataformat
155 * @param array $columns
156 * @param Iterable $iterator Iterable set of records to write
157 * @param callable|null $callback Optional callback method to apply to each record prior to writing
158 * @return stored_file
160 public static function write_data_to_filearea(array $filerecord, string $dataformat, array $columns, Iterable
$iterator,
161 callable
$callback = null): stored_file
{
163 $filepath = self
::write_data($filerecord['filename'], $dataformat, $columns, $iterator, $callback);
165 // Update filename of returned file record.
166 $filerecord['filename'] = basename($filepath);
168 return get_file_storage()->create_file_from_pathname($filerecord, $filepath);