Symfony Flex is Going Serverless
Symfony Flex was introduced in 2017 as one of the key parts of the
reimagined Symfony experience for the Symfony 4 launch. Symfony Flex is a
tool (technically, a Composer plugin) that simplifies the installation/removal
of packages in Symfony applications.
This simplification is made possible thanks to „Flex recipes“, which are a set
of automated instructions that tell Symfony how to install, enable and configure
packages into applications. These recipes are currently stored in two public
GitHub repositories: main recipes repository and contrib recipes repository.
The final piece that makes Flex possible is the Flex server at https://flex.symfony.com.
In addition to showing the available recipes/packages in a web interface, this
server communicates with the Flex Composer plugin to serve recipes.
As part of our continuous efforts to simplify operations, we recently asked
ourselves: how could we simplify the Flex server infrastructure? Then we
thought: what if we remove the Flex server entirely? And that’s exactly what
we’re going to do.
In the pull request #803 of the Symfony Flex package you can see that we’re
going to replace the proprietary flex.symfony.com endpoint by a new endpoint
made of static JSON files hosted on GitHub.
The JSON files are stored in this repository and are generated by GitHub
Actions using this script thanks to a custom recipe checker tool.
The existing Flex server endpoint will keep working for some time as a legacy
service for applications that haven’t been updated yet.
Version 1.16 of symfony/flex has been released with support for the new
endpoints, but they are behind a feature flag for now: you need to set the
FLEX_SERVERLESS env var to 1 to enable the new endpoints.
Please help us confirm that everything works as expected by enabling this
In a few weeks, version 1.17 will remove the feature flag and the new
endpoints will be used by default. All users of legacy versions of
symfony/flex will then see a warning inviting them to upgrade.
A very nice side effect of this change is that you can quite easily host custom
recipes in your own repositories. If you do so, add the URL of your recipe
repository in the extra.symfony.endpoint config option of composer.json
or in the SYMFONY_ENDPOINT env var.
Moreover, now that the proprietary server is gone, you can add your own features
on top of the Symfony Flex API. We’re looking forward to learn about your
ideas. Some of them could even be contributed back to the official Flex API.