This project provides a composer plugin making the Drupal core Composer package work correctly in a Composer project.
This takes care of:
- Placing scaffold files (like
index.php,update.php, …) from thedrupal/coreproject into their desired location inside the web root. Only individual files may be scaffolded with this plugin. - Writing an autoload.php file to the web root, which includes the Composer autoload.php file.
The purpose of scaffolding files is to allow Drupal sites to be fully managed by
Composer, and still allow individual asset files to be placed in arbitrary
locations. The goal of doing this is to enable a properly configured composer
template to produce a file layout that exactly matches the file layout of a
Drupal 8.7.x and earlier tarball distribution. Other file layouts will also be
possible; for example, a project layout very similar to the current
drupal-composer/drupal-project
template will also be provided. When one of these projects is used, the user
should be able to use composer require and composer update on a Drupal site
immediately after extracting the downloaded archive.
Note that the dependencies of a Drupal site are only able to scaffold files if explicitly granted that right in the top-level composer.json file. See allowed packages, below.
Drupal Composer Scaffold is used by requiring drupal/core-composer-scaffold in your
project, and providing configuration settings in the extra section of your
project's composer.json file. Additional configuration from the composer.json
file of your project's dependencies is also consulted in order to scaffold the
files a project needs. Additional information may be added to the beginning or
end of scaffold files, as is commonly done to .htaccess and robots.txt
files. See altering scaffold files for more
information.
Typically, the scaffold operations run automatically as needed, e.g. after
composer install, so it is usually not necessary to do anything different
to scaffold a project once the configuration is set up in the project
composer.json file, as described below. To scaffold files directly, run:
composer drupal:scaffold
Scaffold files are stored inside of projects that are required from the main
project's composer.json file as usual. The scaffolding operation happens after
composer install, and involves copying or symlinking the desired assets to
their destination location. In order to prevent arbitrary dependencies from
copying files via the scaffold mechanism, only those projects that are
specifically permitted by the top-level project will be used to scaffold files.
Example: Permit scaffolding from the project upstream/project
"name": "my/project",
...
"extra": {
"drupal-scaffold": {
"allowed-packages": [
"upstream/project"
],
...
}
}
Allowing a package to scaffold files also permits it to delegate permission to
scaffold to any project that it requires itself. This allows a package to
organize its scaffold assets as it sees fit. For example, if upstream/project
stores its assets in a subproject upstream/assets, upstream/assets would
implicitly be allowed to scaffold files.
It is possible for a project to obtain scaffold files from multiple projects. For example, a Drupal project using a distribution, and installing on a specific web hosting service provider might take its scaffold files from:
- Drupal core
- Its distribution
- A project provided by the hosting provider
- The project itself
Each project allowed to scaffold by the top-level project will be used in turn,
with projects declared later in the allowed-packages list taking precedence
over the projects named before. drupal/core is implicitly allowed and will be
placed at the top of the list. The top-level composer.json itself is also
implicitly allowed to scaffold files, and its scaffold files have highest
priority.
The top-level project in turn must define where the web root is located. It does
so via the locations mapping, as shown below:
"name": "my/project",
...
"extra": {
"drupal-scaffold": {
"locations": {
"web-root": "./docroot"
},
...
}
}
This makes it possible to configure a project with different file layouts; for
example, either the drupal/drupal file layout or the
drupal-composer/drupal-project file layout could be used to set up a project.
If a web-root is not explicitly defined, then it will default to ., the same
directory as the composer.json file.
Sometimes, a project might wish to use a scaffold file provided by a dependency, but alter it in some way. Two forms of alteration are supported: appending and patching.
The example below shows a project that appends additional entries onto the end
of the robots.txt file provided by drupal/core:
"name": "my/project",
...
"extra": {
"drupal-scaffold": {
"file-mapping": {
"[web-root]/robots.txt": {
"append": "assets/my-robots-additions.txt",
}
}
}
}
It is also possible to prepend to a scaffold file instead of, or in addition to appending by including a "prepend" entry that provides the relative path to the file to prepend to the scaffold file.
The example below demonstrates the use of the post-drupal-scaffold-cmd hook
to patch the .htaccess file using a patch.
"name": "my/project",
...
"scripts": {
"post-drupal-scaffold-cmd": [
"cd docroot && patch -p1 <../patches/htaccess-ssl.patch"
]
}
The placement of scaffold assets is under the control of the project that
provides them, but the location is always relative to some directory defined by
the root project -- usually the web root. For example, the scaffold file
robots.txt is copied from its source location, assets/robots.txt into the
web root in the snippet below.
{
"name": "drupal/assets",
...
"extra": {
"drupal-scaffold": {
"file-mapping": {
"[web-root]/robots.txt": "assets/robots.txt",
...
}
}
}
}
Sometimes, a project might prefer to entirely replace a scaffold file provided
by a dependency, and receive no further updates for it. This can be done by
setting the value for the scaffold file to exclude to false:
"name": "my/project",
...
"extra": {
"drupal-scaffold": {
"file-mapping": {
"[web-root]/robots.txt": false
}
}
}
If possible, use the append and prepend directives as explained in altering
scaffold files, above. Excluding a file means that
your project will not get any bug fixes or other updates to files that are
modified locally.
By default, scaffold files overwrite whatever content exists at the target
location. Sometimes a project may wish to provide the initial contents for a
file that will not be changed in subsequent updates. This can be done by setting
the overwrite flag to false, as shown in the example below:
{
"name": "service-provider/d8-scaffold-files",
"extra": {
"drupal-scaffold": {
"file-mapping": {
"[web-root]/sites/default/settings.php": {
"mode": "replace",
"path": "assets/sites/default/settings.php",
"overwrite": false
}
}
}
}
}
Note that the overwrite directive is intended to be used by starter kits,
service providers, and so on. Individual Drupal sites should exclude the file
by setting its value to false instead.
The scaffold tool automatically creates the required autoload.php file at the
Drupal root as part of the scaffolding operation. This file should not be
modified or customized in any way. If it is committed to the repository, though,
then the scaffold tool will stop managing it. If the location of the vendor
directory is changed for any reason, and the autoload.php file has been
committed to the repository, manually delete it and then run composer install
to update it.
Reference section for the configuration directives for the "drupal-scaffold"
section of the "extra" section of a composer.json file appear below.
The allowed-packages configuration setting contains an ordered list of package
names that will be used during the scaffolding phase.
"allowed-packages": [
"example/assets",
],
The file-mapping configuration setting consists of a map from the destination
path of the file to scaffold to a set of properties that control how the file
should be scaffolded.
The available properties are as follows:
- mode: One of "replace", "append" or "skip".
- path: The path to the source file to write over the destination file.
- prepend: The path to the source file to prepend to the destination file, which must always be a scaffold file provided by some other project.
- append: Like
prepend, but appends content rather than prepends. - overwrite: If
false, prevents areplacefrom happening if the destination already exists.
The mode may be inferred from the other properties. If the mode is not specified, then the following defaults will be supplied:
- replace: Selected if a
pathproperty is present, or if the entry's value is a string rather than a property set. - append: Selected if a
prependorappendproperty is present. - skip: Selected if the entry's value is a boolean
false.
Examples:
"file-mapping": {
"[web-root]/sites/default/default.settings.php": {
"mode": "replace",
"path": "assets/sites/default/default.settings.php",
"overwrite": true
},
"[web-root]/sites/default/settings.php": {
"mode": "replace",
"path": "assets/sites/default/settings.php",
"overwrite": false
},
"[web-root]/robots.txt": {
"mode": "append",
"prepend": "assets/robots-prequel.txt",
"append": "assets/robots-append.txt"
},
"[web-root]/.htaccess": {
"mode": "skip",
}
}
The short-form of the above example would be:
"file-mapping": {
"[web-root]/sites/default/default.settings.php": "assets/sites/default/default.settings.php",
"[web-root]/sites/default/settings.php": {
"path": "assets/sites/default/settings.php",
"overwrite": false
},
"[web-root]/robots.txt": {
"prepend": "assets/robots-prequel.txt",
"append": "assets/robots-append.txt"
},
"[web-root]/.htaccess": false
}
Note that there is no distinct "prepend" mode; "append" mode is used to both append and prepend to scaffold files. The reason for this is that scaffold file entries are identified in the file-mapping section keyed by their destination path, and it is not possible for multiple entries to have the same key. If "prepend" were a separate mode, then it would not be possible to both prepend and append to the same file.
By default, append operations may only be applied to files that were scaffolded
by a previously evaluated project. If the force-append attribute is added to
an append operation, though, then the append will be made to non-scaffolded
files if and only if the append text does not already appear in the file. When
using this mode, it is also possible to provide default contents to use in the
event that the destination file is entirely missing.
The example below demonstrates scaffolding a settings-custom.php file, and
including it from the existing settings.php file.
"file-mapping": {
"[web-root]/sites/default/settings-custom.php": "assets/settings-custom.php",
"[web-root]/sites/default/settings.php": {
"append": "assets/include-settings-custom.txt",
"force-append": true,
"default": "assets/initial-default-settings.txt"
}
}
Note that the example above still works if used with a project that scaffolds the settings.php file.
The gitignore configuration setting controls whether or not this plugin will
manage .gitignore files for files written during the scaffold operation.
- true:
.gitignorefiles will be updated when scaffold files are written. - false:
.gitignorefiles will never be modified. - Not set:
.gitignorefiles will be updated if the target directory is a local working copy of a git repository, and thevendordirectory is ignored in that repository.
The locations configuration setting contains a list of named locations that
may be used in placing scaffold files. The only required location is web-root.
Other locations may also be defined if desired.
"locations": {
"web-root": "./docroot"
},
The symlink property causes replace operations to make a symlink to the
source file rather than copying it. This is useful when doing core development,
as the symlink files themselves should not be edited. Note that append
operations override the symlink option, to prevent the original scaffold
assets from being altered.
"symlink": true,
Scaffold files should be treated the same way that the vendor directory is
handled. If you need to commit vendor (e.g. in order to deploy your site),
then you should also commit your scaffold files. You should not commit your
vendor directory or scaffold files unless it is necessary.
If a dependency provides a scaffold file with overwrite set to false, that
file should be committed to your repository.
By default, .gitignore files will be automatically updated if needed when
scaffold files are written. See the gitignore setting in the Specifications
section above.
Some full-length examples appear below.
Sample composer.json for a project that relies on packages that use composer-scaffold:
{
"name": "my/project",
"require": {
"drupal/core-composer-scaffold": "*",
"composer/installers": "^2.3",
"cweagans/composer-patches": "^1.6.5",
"drupal/core": "^8.8.x-dev",
"service-provider/d8-scaffold-files": "^1"
},
"config": {
"optimize-autoloader": true,
"sort-packages": true
},
"extra": {
"drupal-scaffold": {
"locations": {
"web-root": "./docroot"
},
"symlink": true,
"file-mapping": {
"[web-root]/.htaccess": false,
"[web-root]/robots.txt": "assets/robots-default.txt"
}
}
}
}
Sample composer.json for drupal/core, with assets placed in a different project:
{
"name": "drupal/core",
"extra": {
"drupal-scaffold": {
"allowed-packages": [
"drupal/assets",
]
}
}
}
Sample composer.json for composer-scaffold files in drupal/assets:
{
"name": "drupal/assets",
"extra": {
"drupal-scaffold": {
"file-mapping": {
"[web-root]/.csslintrc": "assets/.csslintrc",
"[web-root]/.editorconfig": "assets/.editorconfig",
"[web-root]/.eslintignore": "assets/.eslintignore",
"[web-root]/.eslintrc.json": "assets/.eslintrc.json",
"[web-root]/.gitattributes": "assets/.gitattributes",
"[web-root]/.ht.router.php": "assets/.ht.router.php",
"[web-root]/.htaccess": "assets/.htaccess",
"[web-root]/sites/default/default.services.yml": "assets/default.services.yml",
"[web-root]/sites/default/default.settings.php": "assets/default.settings.php",
"[web-root]/sites/example.settings.local.php": "assets/example.settings.local.php",
"[web-root]/sites/example.sites.php": "assets/example.sites.php",
"[web-root]/index.php": "assets/index.php",
"[web-root]/robots.txt": "assets/robots.txt",
"[web-root]/update.php": "assets/update.php",
}
}
}
}
Sample composer.json for a library that implements composer-scaffold:
{
"name": "service-provider/d8-scaffold-files",
"extra": {
"drupal-scaffold": {
"file-mapping": {
"[web-root]/sites/default/settings.php": "assets/sites/default/settings.php"
}
}
}
}
Append to robots.txt:
{
"name": "service-provider/d8-scaffold-files",
"extra": {
"drupal-scaffold": {
"file-mapping": {
"[web-root]/robots.txt": {
"append": "assets/my-robots-additions.txt",
}
}
}
}
}
Patch a file after it's copied:
"post-drupal-scaffold-cmd": [
"cd docroot && patch -p1 <../patches/htaccess-ssl.patch"
]
Previous versions of Drupal Composer Scaffold (see community project,
drupal-composer/drupal-scaffold)
downloaded each scaffold file directly from its distribution server (e.g.
https://git.drupalcode.org) to the desired destination directory. This was
necessary, because there was no subtree split of the scaffold files available.
Copying the scaffold assets from projects already downloaded by Composer is more
effective, as downloading and unpacking archive files is more efficient than
downloading each scaffold file individually.
The composer/installers plugin is
similar to this plugin in that it allows dependencies to be installed in
locations other than the vendor directory. However, Composer and the
composer/installers plugin have a limitation that one project cannot be moved
inside of another project. Therefore, if you use composer/installers to place
Drupal modules inside the directory web/modules/contrib, then you cannot also
use composer/installers to place files such as index.php and robots.txt
into the web directory. The drupal-scaffold plugin was created to work around
this limitation.