How to detect if a PEAR package is installed in php scripts? - php

Question

I'm trying to write some code to track dependencies. Is there a way to programatically detect if a PEAR package has been installed? I'm thinking something like:
if ($some_pear_api->isPackageInstalled('FooPack')) {
echo 'FooPack is installed!';
} else {
echo 'FooPack is not installed. :(';
}
I know you can simply detect if the class file for that package exists, but I mostly want to know if PEAR has that installed because sometimes some libraries provide other means of including their code (e.g. PHPUnit has a pear channel as well as a git repo.).
Thanks for the help!

Answer 1

You need to use the PEAR_Registry class to do this (which is what the PEAR script itself uses).
Read Adam Harvey's blog post "pear -> list" from 3 years ago - all the details/examples you need are there.
include 'PEAR/Registry.php';
$reg = new PEAR_Registry;
foreach ($reg->listPackages() as $package) {
print "$package\n";
}
If you need this to check for specific versions of each package, then you could base something on the following example, which I provided in a comment to that blog entry:
<?php
require 'PEAR/Registry.php';
$reg = new PEAR_Registry;
define("NAME", 0);
define("VERSION", 1);
$packages = array(
array("PEAR", "1.6.2"),
array("Date", "1.4.7"),
array("Date_Holidays", "0.17.1"),
array("Validate_IE", "0.3.1")
);
foreach ($packages as $package) {
$pkg = $reg->getPackage($package[NAME]);
$version = $pkg->getVersion();
echo "{$package[NAME]} – {$package[VERSION]} – ";
echo version_compare($version, $package[VERSION], '>=') ? 'OK': 'BAD', "\n";
}
?>
If you need to copy and paste this, then it might be best for you to use the version at https://gist.github.com/kenguest/1671361.

Answer 2

You can use Pear/Infos packageInstalled to answer this:
<?php
require_once 'PEAR/Info.php';
$res = PEAR_Info::packageInstalled('FooPack');
if ($res) {
print "Package FooPack is installed \n";
} else {
print "Package FooPack is not yet installed \n";
}
?>

Answer 3

Why not just include the package and see if the class exists?
// Supress Errors. Checking is done below.
#require_once 'PHP/UML.php';
if(!class_exists('PHP_UML'))
{
throw new Exception('PHP_UML is not installed. Please call `pear install PHP_UML` from the command line',1);
}
// Code to use PHP_UML below...
$uml = new PHP_UML();