Composer Support

index.md

@@ -41,7 +41,7 @@ The sponsor is responsible for managing the review stage and votes.
 | N/A | [Mobile App][mobile-app]  | Elisa Foltyn <[email protected]> | N/A |
 | N/A | [Simplify Admin Views*][simplify-admin]  | Elisa Foltyn <[email protected]> | N/A |
 | N/A | [Simplify Admin Views*][simplify-admin2]  | Astrid Günther <[email protected]> | N/A |
-| N/A | [Composer support][composer]  | Astrid Günther <[email protected]> | N/A |
+| N/A | [Composer support][composer]  | Astrid Günther <[email protected]> | Niels Braczek <[email protected]> |
 
 *) Two different proposals on the same target, need to be merged 
 

proposed/composer-meta.md

@@ -0,0 +1,121 @@
+# Composer Meta Document
+
+## 1. Summary
+
+[Composer](https://getcomposer.org/)  is a tool for dependency management in PHP. It allows declaring, installing and
+updating the libraries a project depends on.
+
+Joomla's Composer support means that extensions of all kinds can be treated in the same way as libraries.
+
+## 2. Why Bother?
+
+Composer has long been used in Joomla to control the dependencies of libraries. The automatic comparison of the various
+requirements, compatibilities and incompatibilities offers a comfort that none of the Joomla Core developers would want
+to miss.
+
+Without Composer support, it is at best very difficult for extension developers to provide their own libraries, because
+they cannot know whether extensions are already installed that use libraries that may not be compatible with their own
+library.
+
+Additionally, there are groups in the Joomla ecosystem for whom the web-based installation is an obstacle because they
+have to perform the same activity over and over again in a time-consuming manner. These include agencies that build many
+websites, hosters who want to install Joomla at the push of a button, or cloud services and appliance providers. If
+Joomla and its extensions can be managed via Composer, it will be easier and more attractive for them to offer Joomla in
+their portfolio.
+
+A large number of projects have already opened up to this market and offer the Composer-based installation of both the
+main project and associated extensions:
+
+- [TYPO3](https://docs.typo3.org/m/typo3/guide-installation/master/en-us/QuickInstall/Composer/Index.html) ([GitHub](https://github.com/TYPO3/CmsComposerInstallers))
+- [Contao](https://docs.contao.org/books/manual/current/en/01-installation/installing-contao.html#installing-with-composer)
+- [Drupal](https://www.drupal.org/docs/develop/using-composer/using-composer-to-install-drupal-and-manage-dependencies)
+- [WinterCMS](https://wintercms.com/docs/help/using-composer) (formerly known as October CMS)
+- [Kirby](https://getkirby.com/docs/cookbook/setup/composer)
+- [SilverStripe](https://docs.silverstripe.org/en/4/getting_started/composer/)
+- [Pico](https://picocms.org/docs/)
+- [Craft CMS](https://craftcms.com/docs/3.x/installation.html)
+
+## 3. Scope
+
+### 3.1 Goals
+
+Composer support is designed to help enterprise users with their work by providing the following features:
+
+* Installing the CMS
+* Installing extensions
+* Updating the CMS
+* Updating extensions
+* Uninstalling the CMS
+* Uninstalling extensions
+* Integrating PHP libraries
+
+### 3.2 Non-Goals
+
+Composer may not be usable everywhere. Therefore, Composer support cannot and should not aim to replace the web-based
+installation process.
+
+> Blog post from 2017 on OSTraining:
+> [5 Reasons Not to Require Composer in Your CMS](https://www.ostraining.com/blog/coding/composer-cms/).
+> The reservations listed are quite understandable. However, they refer to Composer as a requirement without an
+> alternative.
+
+## 4. Approaches
+
+### 4.0 Probable Problems
+
+#### "Dependency Hell"
+
+If extension A requires version X and another extension B requires an incompatible version Y of the same external
+library, one of those extensions cannot be installed. On the other hand, under normal circumstances, the two extensions
+would not run in the same thread, so they *could* use their own library version.
+
+> Is 'prefixing' a solution in those cases?
+
+### 4.1 Basic Usage
+
+#### Installing Joomla
+
+```shell
+composer create-project joomla/joomla-cms <your/installation/directory> ["<version>"]
+```
+
+#### Installing an Extension
+
+```shell
+composer require <package/name> ["<version constraint>"]
+```
+
+### 4.2 Publishing Extensions
+
+### 4.3 Comparison of Approaches
+
+### 4.4 Chosen Approach
+
+## 5. Design Decisions
+
+## 6. People
+
+### 6.1 Editor(s)
+
+* Astrid Günther <[email protected]>
+
+### 6.2 Sponsors
+
+* Niels Braczek <[email protected]>
+
+### 6.3 Contributors
+
+* N/A
+
+## 7. Votes
+
+* **Entrance Vote:** _(not yet taken)_
+* **Acceptance Vote:** _(not yet taken)_
+
+## 8. Relevant Links
+
+_**Note:** Order descending chronologically._
+
+## 9. Errata
+
+...

proposed/composer.md

@@ -0,0 +1,45 @@
+# Real Composer Support
+
+This document describes ...
+
+The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD",
+"SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be
+interpreted as described in [RFC 2119][].
+
+[RFC 2119]: http://tools.ietf.org/html/rfc2119
+
+### References
+
+- [RFC 2119][]: Key words for use in RFCs to Indicate Requirement Levels
+
+## 1. Specification
+
+### 1.1 Spec A
+
+### 1.2 Spec B
+
+## 2. Interfaces
+
+### 2.1 Interface A
+
+The following interface MUST be implemented by compatible ...
+
+```php
+namespace ...;
+
+interface ...
+{
+}
+```
+
+### 2.2 Inteface B
+
+The following interface MUST be implemented by compatible ...
+
+```php
+namespace ...;
+
+interface ...
+{
+}
+```