CLI scripts

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.