CLI scripts: Difference between revisions
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All scripts must declare themselves as CLI scripts properly by setting the <tt>CLI_SCRIPT</tt> constant before loading the main <tt>config.php</tt> file. | All scripts must declare themselves as CLI scripts properly by setting the <tt>CLI_SCRIPT</tt> constant before loading the main <tt>config.php</tt> file. | ||
< | <syntaxhighlight lang="php"> | ||
define('CLI_SCRIPT', true); | define('CLI_SCRIPT', true); | ||
require(__DIR__ . '/../../../config.php'); | require(__DIR__ . '/../../../config.php'); | ||
</ | </syntaxhighlight> | ||
The path to the config.php must not use relative paths starting with <tt>../</tt>. The best practise is to avoid <tt>dirname()</tt> function call and use the <tt>__DIR__</tt> magic constant (this applies everywhere, not just for CLI scripts). | The path to the config.php must not use relative paths starting with <tt>../</tt>. The best practise is to avoid <tt>dirname()</tt> function call and use the <tt>__DIR__</tt> magic constant (this applies everywhere, not just for CLI scripts). | ||
Line 22: | Line 22: | ||
The library <tt>clilib.php</tt> provides useful functions for basic input/output operations in CLI scripts. | The library <tt>clilib.php</tt> provides useful functions for basic input/output operations in CLI scripts. | ||
< | <syntaxhighlight lang="php"> | ||
require_once($CFG->libdir . '/clilib.php'); | require_once($CFG->libdir . '/clilib.php'); | ||
</ | </syntaxhighlight> | ||
;cli_write():Write a text to the given stream, defaults to the standard output (since Moodle 3.0) | ;cli_write():Write a text to the given stream, defaults to the standard output (since Moodle 3.0) | ||
Line 58: | Line 58: | ||
== Example == | == Example == | ||
< | <syntaxhighlight lang="php"> | ||
<?php | <?php | ||
// This file is part of Moodle - https://moodle.org/ | // This file is part of Moodle - https://moodle.org/ | ||
Line 121: | Line 121: | ||
// Do something useful here. | // Do something useful here. | ||
</ | </syntaxhighlight> |
Latest revision as of 13:38, 14 July 2021
CLI (command line interface) scripts can be executed from the command line (terminal) only.
Location
It is a convention in the Moodle code that all CLI scripts are put into the cli/ folder inside the component/plugin directory.
Examples: admin/cli/, enrol/ldap/cli/, admin/tool/task/cli/ and others
CLI_SCRIPT constant
All scripts must declare themselves as CLI scripts properly by setting the CLI_SCRIPT constant before loading the main config.php file.
define('CLI_SCRIPT', true);
require(__DIR__ . '/../../../config.php');
The path to the config.php must not use relative paths starting with ../. The best practise is to avoid dirname() function call and use the __DIR__ magic constant (this applies everywhere, not just for CLI scripts).
clilib.php
The library clilib.php provides useful functions for basic input/output operations in CLI scripts.
require_once($CFG->libdir . '/clilib.php');
- cli_write()
- Write a text to the given stream, defaults to the standard output (since Moodle 3.0)
- cli_writeln()
- Write a text followed by an end of line symbol to the given stream (since Moodle 3.0)
- cli_input()
- Prompt the user for an input value
- cli_get_params()
- Parse and return arguments passed to the script
- cli_separator()
- Print or return section separator string
- cli_heading()
- Print or return section heading string
- cli_problem()
- Print error notification
- cli_error()
- Print message to the standard error output and exit with the given code
- cli_logo()
- Prints ascii-graphics Moodle logo
Script parameters
The function cli_get_params() implements a basic cross-platform parser for the script parameters. It supports long options names (with double dashes like --version or --help) by default. Some of these long options can have short name aliases (single dashed, like -v or -h). The function does not support positional arguments for CLI scripts. Input data must be provided as a value of an option:
GOOD:
$ php do_something_useful.php --file=/path/to/file.mbz --action=validate
BAD:
$ php do_something_useful.php validate /path/to/file.mbz
It is a good practise that short names aliases should be used only for boolean options (flags). It is unusual in CLI environment to set values for short named options.
NICE:
$ php do_something_useful.php -h
UGLY:
$ php do_something_useful.php -f=/path/to/file.mbz
For documenting the expected usage of the script, you may want to use the same format and syntax as used by docopt.
Example
<?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/>.
/**
* Moodle CLI script - demo.php
*
* @package plugintype_pluginname
* @copyright 2019 Your Name <email@example.com>
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
define('CLI_SCRIPT', true);
require(__DIR__ . '/../../../config.php');
require_once($CFG->libdir . '/clilib.php');
$usage = "Put a one line summary of what the script does here.
Usage:
# php demo.php --paramname=<value>
# php demo.php [--help|-h]
Options:
-h --help Print this help.
--paramname=<value> Describe the parameter and the meaning of its values.
";
list($options, $unrecognised) = cli_get_params([
'help' => false,
'paramname' => null,
], [
'h' => 'help'
]);
if ($unrecognised) {
$unrecognised = implode(PHP_EOL . ' ', $unrecognised);
cli_error(get_string('cliunknowoption', 'core_admin', $unrecognised));
}
if ($options['help']) {
cli_writeln($usage);
exit(2);
}
if (empty($options['paramname'])) {
cli_error('Missing mandatory argument paramname.', 2);
}
// Do something useful here.