silverstripe-framework/docs/en/00_Getting_Started/02_Composer.md

title	summary
Composer	What is composer and how to use it with Silverstripe CMS

Using Silverstripe CMS with Composer

Requirements

Composer is a package management tool for PHP that lets you install and upgrade Silverstripe CMS and its modules. We also have separate instructions for installing modules with Composer.

Before installing Composer you should ensure your system has the version control system, Git installed. Composer uses Git to check out the code dependancies you need to run your Silverstripe CMS website from the code repositories maintained on GitHub.

Next, install composer. For our documentation we assume the composer command is installed globally. You should now be able to run the command:

composer help

Create a new site

Composer can create a new site for you, using the installer as a template. By default it will download the latest stable version:

composer create-project silverstripe/installer my-project

If you want to get all additional fixtures for testing, such as behat and phpunit configuration, an example .env.example file, and all documentation, then it's recommended to use --prefer-source to include these files.

If you want a minimal installation with the bare essentials to get working without any additional overhead, and don't plan on contributing back changes to framework, use --prefer-dist (default) for a more lightweight install.

./my-project should be the root directory where your site will live. For example, on OS X, you might use a subdirectory of ~/Sites. As long as your web server is up and running, this will get all the code that you need. Now visit the site in your web browser, and the installation process will be completed.

You can also specify a version to download that version explicitly, i.e. this will download the older 4.3.3 release:

composer create-project silverstripe/installer ./my-project 4.3.3

When create-project is used with a release version like above, it will try to get the code from archives instead of creating git repositories. If you're planning to contribute to Silverstripe CMS, see Using development versions.

Adding modules to your project

Composer isn't only used to download Silverstripe CMS, it is also used to manage all Silverstripe CMS modules. You can find thousands of modules on https://addons.silverstripe.org. Installing a module can be done with the following command:

composer require silverstripe/blog

This will install the silverstripe/blog module in the latest compatible version. If you know the specific version you want to install already (such as ^2), you can add it after the package name as a version constraint:

composer require silverstripe/blog ^2

[warning] Version constraints: master is not a legal version string - it's a branch name. These are different things. The version string that would get you the branch is dev-master. The version string that would get you a numeric branch is a little different. The version string for the 4 branch is 4.x-dev. [/warning]

Updating dependencies

Except for the control code of the Voyager space probe, every piece of code in the universe gets updated from time to time. Silverstripe CMS modules are no exception.

To get the latest updates of the modules in your project, run this command:

composer update

Updates to the required modules will be installed, and the composer.lock file will get updated with the specific commits and version constraints for each of them.

Deploying projects with Composer

When deploying projects with composer, you could just push the code and run composer update. This, however, is risky. In particular, if you were referencing development dependencies and a change was made between your testing and your deployment to production, you would end up deploying untested code. Not cool!

The composer.lock file helps with this. It references the specific commits that have been checked out, rather than the version string. You can run composer install to install dependencies from this rather than composer.json.

So your deployment process, as it relates to Composer, should be as follows:

• Run composer update on your development version before you start whatever testing you have planned. Perform all the necessary testing.
• Check composer.lock into your repository.
• Deploy your project code base, using the deployment tool of your choice.
• Run composer install --no-dev -o on your production version. In this command, the --no-dev command tells Composer not to install your development-only dependencies, and -o is an alias for --optimise-autoloader, which will convert your PSR-0 and PSR-4 autoloader definitions into a classmap to improve the speed of the autoloader.

Composer managed modules, Git and .gitignore

Modules and themes managed by Composer should not be committed with your projects source code. Silverstripe CMS ships with a .gitignore file by default which prevents this. For more details read Should I commit the dependencies in my vendor directory? .

Dev Environments for Contributing Code

So you want to contribute to Silverstripe CMS? Fantastic! You can do this with composer too. You have to tell composer three things in order to be able to do this:

• Keep the full git repository information
• Include dependencies marked as "developer" requirements
• Use the development version, not the latest stable version

The first two steps are done as part of the initial create project using additional arguments.

composer create-project --keep-vcs --dev silverstripe/installer ./my-project 4.x-dev --prefer-source

The process will take a bit longer, since all modules are checked out as full git repositories which you can work on. The command checks out from the 4.x release line. To check out from master instead, replace 4.x-dev with dev-master (more info on composer version naming).

The --keep-vcs flag will make sure you have access to the git history of the installer and the requirements

The --dev flag is optional, and can be used to add a couple modules which are useful for Silverstripe CMS development:

• The behat-extension module allows running Behat integration tests
• The docsviewer module will let you preview changes to the project documentation
• The buildtools module which adds phing tasks for creating Silverstripe CMS releases

Once the create-project command completes, you need to edit the composer.json in the project root and remove the @stable markers from the silverstripe/cms and silverstripe/framework version entries. Another composer update --dev call will now fetch from the development branch instead. Note that you can also convert an existing composer project with these steps.

Please read the "Contributing Code" documentation to find out how to create forks and send pull requests.

Advanced usage

Manually editing composer.json

To remove dependencies, or if you prefer seeing all your dependencies in a text file, you can edit the composer.json file. It will appear in your project root, and by default, it will look something like this:

{
    "name": "silverstripe/installer",
    "description": "The Silverstripe Framework Installer",
    "require": {
        "php": ">=7.3",
        "silverstripe/cms": "^4",
        "silverstripe/framework": "^4",
        "silverstripe-themes/simple": "^3"
    },
    "require-dev": {
        "silverstripe/docsviewer": "^3"
    },
    "minimum-stability": "dev",
    "prefer-stable": true
}

To add modules, you should add more entries into the "require" section. For example, we might add the blog and forum modules. Be careful with the commas at the end of the lines!

Save your file, and then run the following command to refresh the installed packages:

composer update

Using development versions

Composer will by default download the latest stable version of silverstripe/installer. The composer.json file that comes with silverstripe/installer may also explicitly state it requires the stable version of cms and framework - this is to ensure that when developers are getting started, running composer update won't upgrade their project to an unstable version

However it is relatively easy to tell composer to use development versions. Not only is this required if you want to contribute back to the Silverstripe CMS project, it also allows you to get fixes and API changes early.

This is a two step process. First you get composer to start a project based on the latest unstable silverstripe/installer

composer create-project silverstripe/installer ./my-project dev-master

Or for the latest development version in the 4.0.x series

composer create-project silverstripe/installer ./my-project 4.0.x-dev

Working with project forks and unreleased modules

By default, Composer will install modules listed on the Packagist site. There are a few reasons that you might not want to do this. For example:

• You may have your own fork of a module, either specific to a project, or because you are working on a pull request
• You may have a module that hasn't been released to the public.

There are many ways that you can address this, but this is one that we recommend, because it minimises the changes you would need to make to switch to an official version in the future.

This is how you do it:

• Ensure that all of your fork repositories have correct composer.json files. Set up the project forks as you would a distributed package. If you have cloned a repository that already has a composer.json file, then there's nothing you need to do, but if not, you will need to create one yourself.

• List all your fork repositories in your project's composer.json files. You do this in a repositories section. Set the type to vcs, and url to the URL of the repository. The result will look something like this:

{
    "name": "silverstripe/installer",
    "description": "The Silverstripe Framework Installer",
    "repositories": [
        {
            "type": "vcs",
            "url": "git@github.com:sminnee/silverstripe-cms.git"
        }
    ]
}

• Install the module as you would normally. Use the regular composer function - there are no special flags to use a fork. Your fork will be used in place of the package version.

composer require silverstripe/cms

Composer will scan all of the repositories you list, collect meta-data about the packages within them, and use them in favour of the packages listed on packagist. To switch back to using the mainline version of the package, just remove the repositories section from composer.json and run composer update.

Now add an "upstream" remote to the original repository location so you can rebase or merge your fork as required.

cd cms
git remote add -f upstream git://github.com/silverstripe/silverstripe-cms.git

For more information, read the "Repositories" chapter of the Composer documentation.

Forks and branch names

Generally, you should keep using the same pattern of branch names as the main repositories does. If your version is a fork of 4.0, then call the branch 4.0, not 4.0-myproj or myproj. Otherwise, the dependency resolution gets confused.

Sometimes, however, this isn't feasible. For example, you might have a number of project forks stored in a single repository, such as your personal GitHub fork of a project. Or you might be testing/developing a feature branch. Or it might just be confusing to other team members to call the branch of your modified version 4.0.

In this case, you need to use Composer's aliasing feature to specify how you want the project branch to be treated, when it comes to dependency resolution.

Open composer.json, and find the module's require. Then put as (core version name) on the end.

{
    "require": {
        "php": ">=5.5.0",
        "silverstripe/cms": "3.5.1.2",
        "silverstripe/framework": "dev-myproj as 4.0.x-dev",
        "silverstripe-themes/simple": "~3.2.0"
    }
}

What this means is that when the myproj branch is checked out into a project, this will satisfy any dependencies that 4.0.x-dev would meet. So, if another module has "silverstripe/framework": "^4.0.0" in its dependency list, it won't get a conflict.

Both the version and the alias are specified as Composer versions, not branch names. For the relationship between branch/tag names and Composer versions, read the relevant Composer documentation.

This is not the only way to set things up in Composer. For more information on this topic, read the "Aliases" chapter of the Composer documentation.

FAQ

Error "The requested package silverstripe/framework 1.0.0 could not be found"

Composer needs hints about the base package version, either by using composer create-project as described above, or by checking out the silverstripe-installer project directly from version control. In order to use Composer on archive downloads from silverstripe.org, or other unversioned sources, an advanced workaround is to set the COMPOSER_ROOT_VERSION before every command (details)

How do I convert an existing module to using Composer?

Simply decide on a unique name and vendor prefix, create a composer.json, and either commit it or send a pull request to the module author. Look at existing modules like the "blog" module for good examples on what this file should contain. It's important that the file contains a custom "type" to declare it as a silverstripe-module or silverstripe-theme ( see custom installers). Then register the module on packagist.org.

How should I name my module?

Follow the packagist.org advice on choosing a unique name and vendor prefix. Please don't use the silverstripe/<modulename> vendor prefix, since that's reserved for modules produced by Silverstripe Ltd. In order to declare that your module is in fact a Silverstripe CMS module, use the "silverstripe" tag in the composer.json file, and set the "type" to "silverstripe-module".

What about themes?

Themes are technically just "modules" which are placed in the themes/ subdirectory. We denote a special type for them in the composer.json ("type": "silverstripe-theme"), which triggers their installation into the correct path.

How do I convert an existing project to Composer?

Copy the composer.json file from a newer release, and adjust the version settings in the "require" section to your needs. Then refer to the upgrading documentation. You'll also need to update your webserver configuration from there (.htaccess or web.config files), in order to prevent web access to the composer-generated files.

Do I need composer on my live server?

It depends on your deployment process. If you copy or rsync files to your live server, the process stays the same. If the live server hosts a git repository checkout, which is updated to push a newer version, you'll also need to run composer install afterwards. We recommend looking into Composer "lock" files for this purpose.

Can I keep using Downloads, Subversion Externals or Git Submodules?

Composer is more than just a file downloader. It comes with additional features such as autoloading or scripts which some modules will start relying on. Please check the module README for specific installation instructions.

I don't want to get development versions of everything!

You don't have to, Composer is designed to work on the constraints you set. You can declare the "minimum-stability" on your project as suitable, or even whitelist specific modules as tracking a development branch while keeping others to their stable release. Read up on Composer "lock" files on how this all fits together.