What is SymfonyCloud?
What is SymfonyCloud?¶
Welcome to SymfonyCloud, the Symfony PaaS. SymfonyCloud is a Platform-as-a-Service built and optimized for Symfony developers.
SymfonyCloud is tightly integrated with the Symfony ecosystem and its conventions to make developers more productive.
You can think of SymfonyCloud as being the hosting framework part of Symfony. It abstracts your project infrastructure and manages it for you: never install nor configure services like a web server, a MySQL database, or a Redis cache again.
SymfonyCloud is built on one main idea: your server infrastructure is part of your application, so it should be version controlled along with your application.
Every branch you push to your Git repository can come with bug fixes, new features, and infrastructure changes. Everything can then be tested as an independent deployment, including the application code and all services with a copy of their data (database entries, search index, user files, …).
It really is “what would my site look like if I merge these changes to production?”
On SymfonyCloud, a project is linked to a Git repository. A project is
composed of one or more applications. An application is a directory in your
Git repository with a specific SymfonyCloud configuration and dedicated HTTP
endpoints (via the
Projects are deployed in environments. An environment is a standalone copy of your live applications which can be used for testing, Q&A, implementing new features, fixing bugs, …
Every project you deploy on SymfonyCloud is built as a virtual cluster, containing a series of containers. The master branch of your Git repository is always deployed as a production cluster. Any other branch can be deployed as a development cluster.
There are three types of containers within your cluster, all configured by files stored along side your code:
- The Router, configured in
.symfony/routes.yaml, is a single nginx process responsible for mapping incoming requests to an Application container, and to optionally provide HTTP caching.
- One or more Applications, configured via
.symfony.cloud.yamlfiles, holding the code of your project.
- Some optional Services, configured in
.symfony/services.yaml, like MySQL/MariaDB, Elasticsearch, Redis, or RabbitMQ; they come as optimized pre-built images.
Every time you deploy a branch to SymfonyCloud, the code is built and then deployed on a new cluster.
The build process looks through the configuration files in your repository and assembles the necessary containers.
The deploy process makes those containers live, replacing the previous versions, with no service downtime.
Building the Application¶
During the build step, any dependencies specified in
installed on application containers.
You can also customize the build step but providing a
build hook composed of
one or more shell commands that help creating your production code base. That
could be compiling TypeScript files, running some scripts, rearranging files on
disk, or whatever else you want. Note that at this point all you have access to
is the filesystem; there are no services or other databases available. Your live
website is unaffected.
The default build step for Symfony removes development front controllers and warms up the cache.
Once all of that is completed, the filesystem is frozen and a read-only container image is created. That filesystem is the final build artifact.
Deploying the Application¶
Before starting the deployment of your application, we pause all incoming requests and hold them so that there is no downtime.
Then, we stop the current containers and start the new ones. We then open networking connections between the various containers, as specified in the configuration files. The connection information for each service is available as environment variables.
As for the build step, you can define a deploy hook to prepare your application. Your application has complete access to all services, but the filesystem where your code lives is now read-only.
The default deploy step for Symfony replaces the current cache with the newly warmed up one and, for the web container, runs Doctrine migrations if any.
Finally, we open the floodgates and let incoming requests through your newly deployed application. You are done!
If you’re facing any issue with SymfonyCloud, you can submit a support ticket
from a terminal via
symfony open:support or visit the support webpage.
This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.