mindplay/composer-locator

This Composer plugin provides a means of locating the installation path for a given Composer package name.

Use this to locate vendor package roots, e.g. when working with template files or other assets in a package.

It works regardless of installers affecting the individual package installation paths, and also works whether the package in question is currently the root package/project or a dependency.

You can think of this as a minimalist alternative to puli - rather than abstracting repositories and resources through a complex virtual file system, I prefer to just use the physical file system and standard PHP APIs.

Works for me. I like simple things. YMMV.

Usage

Add to your composer.json file:

{
    "require": {
        "mindplay/composer-locator": "^2"
    }
}

Running composer install or composer update will bootstrap your project with a generated class containing a registry of Composer package installation paths.

To obtain the installation path for given package:

$path = ComposerLocator::getPath("vendor/package"); // => "/path/to/vendor/package" 

If the specified package name is not found, the function throws a RuntimeException.

To check whether a given package is installed:

$is_installed = ComposerLocator::isInstalled("vendor/package"); // => (bool) true|false 

The root project package doesn't necessarily have a package name - in that case, or in other cases where you need the project root path, you can obtain it directly:

$path = ComposerLocator::getRootPath(); // => "/path/to/project/root" 

You can also get a list of all installed packages via ComposerLocator::getPackages(), or obtain the full map of vendor/package names to absolute root paths via ComposerLocator::getPaths().

Why?

Needing to know the root path of a package installation folder is quite a common requirement, such as when you need to specify paths to template files or other assets.

The problem is that Composer itself offers no simple and reliable way to do that.

You can use reflection to get the path to a known class or interface from the package, and then dirname() up from your src folder to the package installation root, but that approach is pretty clumsy and creates random dependencies on arbitrary class/interface-names, just for the sake of locating a package root.

Even if you know the path of the vendor root folder, and the {vendor}/{package} folder name convention, there is no guarantee that's always where packages are installed - something like composer-installers or other custom installers could affect the installation paths.

Also, under test, when a package is the root/project package, of course the assumption about the vendor folder is always going to be wrong.