The Discovery Component

The Discovery Component connects Composer packages that consume resources with Composer packages that provide resources.

The Problem

At the moment, you need to write a lot of boilerplate code if you use different packages that use each other’s files. Suppose you install the following two packages in your application:

  • The package thor/translator, which uses *.yml files to translate text to some language.
  • The package batman/blog, which contains the files blog.en.yml and with translations for the strings in the package.

As user of these packages, you have to register the *.yml files with the Translator instance of the thor/translator package:

$translator = new Translator(array(

If you’re lucky, your framework does this job for you. However, offloading this task to framework developers doesn’t scale, since for any combination of package and framework, someone needs to write and maintain such integration code. That’s a lot of duplicated work.

How It Works

Puli’s Discovery Component solves this problem by decentralizing the resource registration process. Composer packages are divided into resource consumers and resource providers.

Puli's Resource Discovery Component.

Resource consumers, like our translator, register a name for the resources they want to use. This name is called a binding type. In this example, the developer of the translator defines the binding type “thor/translations” and publishes that type in their documentation.

Other packages (the resource providers) assign their translation files to this binding type. This is called a binding. In the end, the translator fetches all translation files for its binding type from a ResourceDiscovery instance.

By communicating only through Puli’s Discovery Component and a common binding type, consumers and providers are completely decoupled from each other. As user of these packages, you only need to pass the ResourceDiscovery instance to the translator:

$translator = new Translator($discovery);

Puli takes care of everything else.

Getting Started

Read Getting Started with the Discovery Component to learn how to install and use the Discovery Component in your project.