If you are using PHP version 8, some plugins that are not yet supported may cause installation errors.

composer install --ignore-platform-req=phporcomposer install --ignore-platform-reqs

This option can be used to set specific requirements that composer can ignore.

question

In addition to the versions of other packages they require, Composer packages can also specify the PHP versions they support.

When parsing the version of a package to install, Composer must find a version that matches all constraints:

• The version constraints you specify for dependencies incomposer.json
• The version constraints specified by each package for its dependencies
• Supported PHP versions for each package

If there is no package that satisfies all these constraints, you will receive an error.

Common confusion

Please note that version constraints for PHP versions followthe same rules as other Composer constraints. Therefore, the constraint^7.0means "any 7.x version above 7.0", excluding 8.0.

solution

To solve this problem, you need to relax one of the constraints:

1. Look at the package mentioned in the error message (e.g.acme/some-packagein the example) and install it inPackagist(or any custom package source you configured) Find it on .
2. Check to see if there is a new version that supports your PHP version.
3. If not, you need to find out what needs to be added to support that. This might mean checking out the project directly, running its tests and submitting a patch to mark it as compatible with the new version.
4. If (when) support is added, you need to ensure that yourcomposer.jsonand other dependent packages do not exclude that new version. For example, if you currently depend on version^1.0ofacme/some-package, but PHP 8.0 is only supported starting with version 2.2.0, you will need to change the constraint to^2.2and make sure your application is still compatible.

Temporary solution

Sometimes you are pretty sure that your application will run correctly using the same package version as before. In this case, you can useplatformconfiguration variablesincomposer.jsonto pretend you are still using the old version.This should only be used as a temporary workaround or for testing, as it means that packages may be installed that will not work at all on your new PHP version.

For example:

{ "config": { "platform": { "php": "7.4.999" } } }

See also "Overriding PHP base dependencies in Composer"