PHP CLI Tips and Tricks

It's not called the Command Line Interface for nothing. I programmed in PHP for a long time without even looking at the PHP CLI. When I finally did, I started appreciating all of its usefulness and features. Now I'd say I use it almost every day.

In this article, I'll show you three quick tips that can boost your PHP development productivity. Let's dive right in:

`php -r`

Did you know you can execute a line of PHP with the -r option? Use it like this:

% php -r 'echo "Hello world!\n";'
Hello world!

Note that everything inside the single apostrophes must be valid PHP syntax, so mind your double quotes and semi-colons. This has a number of uses. For example, how about some quick math?

% php -r 'echo sqrt(150)."\n";'
12.247448713916

Or finding out what week of the year we're in?

%$ php -r 'echo date("W") . "\n";'
26

Or finding out what day of the week Independence Day in the U.S. falls on next year?

% php -r 'echo date("l", strtotime("2009-07-04")) . "\n";'
Saturday

Or generating a random number for the office raffle?

% php -r 'echo rand(0, 100) . "\n";'
33

Sometimes, I just need a bunch of random letters and numbers. I find a random md5 hash usually does the trick:

% php -r 'echo md5(uniqid(rand(), true)) . "\n";'
faa5f6cd713bcfb64aa0b297d62c5345

You get the idea.

PHP Interactive Shell

I don’t know whether it’s really a shell, but it gets the job done. Have you ever wanted to test a small snippet of PHP code? You might have a small test script somewhere under a web server root you can quickly access. It’s a pain. With interactive PHP, you can test these right from the command line!

% php -a
Interactive mode enabled

<?php
echo "hello world!\n";
hello world!
exit;
%

This is great for figuring out little problems or little snippets of code while developing. For example, I can never remember where the $haystack and where the $needle go in assorted string functions:

% php -a
Interactive mode enabled
<?php
// does the $needle or $haystack come first?
echo strpos("lo", "hello");
echo strpos("hello", "lo");
3
// so the $haystack comes first

Or how about figuring out that regular expression you need?

% php -a
Interactive mode enabled
<?php
// get rid of all characters but "abc"
$regex = "/^[abc]/";
echo preg_replace($regex, "", "abcdef");
bcdef
// oops, that gets rid of [abc] occurring at the line beginning
// let's try again
$regex = "/[^abc]/";
echo preg_replace($regex, "", "abcdef");
abc
// that's what I wanted

PHP Command Interpreter

This isn't really a command-line tip, but you might it useful if you are on Unix. You know you can execute a PHP script by running php myscript.php, but did you know you don't even need the php command?

When Unix runs a script, it looks for a command interpreter to interpret the script at the very top of the file. The command interpreter line begins with the shebang string (#!). You probably have done this with shell scripts, but you can do it with PHP scripts as well. So, if you have a PHP script named myscript.php that looks like this:

#!/usr/bin/php
<?php
echo "Hello world again!\n";
?>

You can run this script by running the file name:

% ./myscript.php
Hello world again!

(Make sure the file is executable.) So if you have an awesome PHP script that does some task for you, or a PHP script that deploys your site, you can put the script in your $PATH and simply call it like any other Unix command.

That's about it. There are a few other PHP CLI features you might find useful. For example, php -l will run a syntax check on PHP code, and php -i will give you output similar to the phpinfo() function.

Are there any other interesting ways you've used the PHP CLI?