Creating a Command-Line Tool with PHP

A command-line PHP tool reads arguments, performs a task and returns meaningful exit status.

What It Does

A command-line PHP tool reads arguments, performs a task and returns meaningful exit status. The following examples distinguish a normal use case, a boundary case and a practical application.

Requirements and Compatibility

PHP 8.x and a local test environment. Apply input validation, correct error handling and the requirements of any optional libraries.

The code focuses on the core concept. Production implementation may also need routes, validation, persistence, authorization or deployment tooling.

Example 1: Basic Behavior

Understand the primary operation and its inputs.

<?php
$argv = ['tool.php', '--task=export'];
$task = str_starts_with($argv[1], '--task=') ? substr($argv[1], 7) : '';
echo $argv[1]; // For actual parsing, call getopt() on the live CLI process

Example 2: Another Case

Check failure behavior or a different execution path.

<?php
$args = ['script.php', '--count', '5'];
$index = array_search('--count', $args, true);
$count = $index !== false ? filter_var($args[$index + 1] ?? null, FILTER_VALIDATE_INT) : false;
echo $count === false ? 'Invalid count' : $count;

Practical Example: Putting It to Use

Apply the behavior in a small, controlled scenario.

<?php
$total = 4;
for ($current = 1; $current <= $total; $current++) { echo sprintf('\r[%s%s] %d/%d', str_repeat('#', $current), str_repeat('-', $total - $current), $current, $total); }
echo '\n';

Important Behavior and Edge Cases

Do not rely on web-request variables or assume a TTY is always available.

Comparison with Related Functions or Approaches

Option	What it means in practice
Creating a Command-Line Tool with PHP	A command-line PHP tool reads arguments, performs a task and returns meaningful exit status.
Related approach	Use $argv/getopt() and send diagnostics to stderr.

Common Beginner Mistakes

Mistake	Correct approach
Ignoring the important boundary for Creating a Command-Line Tool with PHP	Do not rely on web-request variables or assume a TTY is always available.
Assuming a related mechanism has the same behavior	Use $argv/getopt() and send diagnostics to stderr.

Key Takeaways

A command-line PHP tool reads arguments, performs a task and returns meaningful exit status.
Do not rely on web-request variables or assume a TTY is always available.
Use $argv/getopt() and send diagnostics to stderr.

Before adapting these examples, verify the return values, test the failure paths and confirm that your application meets its security and environment requirements.