Docker support

[dunglas]

Hi,

I've created an alternative Symfony skeleton with Docker support: https://github.com/dunglas/symfony-docker-skeleton
It's basically the API Platform Docker setup tuned to support Flex.

It works, but some minimal modifications can be done to some recipes to ease the install (expect some PRs soon).

Main differences with the standard skeleton are:

• It doesn't use the Dotenv component (Docker has a builtin support of .env files)
• In dev mode, the front controller can be accessed from the host

It's probably possible to go one step further and to automatically add required services with a Configurator (e.g: add a Redis image to docker-compose.yml when installing predis/predis).

Is it something you may include into Flex?

[fabpot]

That's very interesting and definitely a scenario that should work with Flex. I would really like if we could have automatic configuration based on what packages you install (like your Redis example). Not sure we have the right abstractions for that right now, but happy to add anything that would help going in that direction. I wanted to be able to do the same for SensioCloud. So, that would benefit more than just Docker.

The only thing we need to think of is the override of the web/index.php file.

In any case, please continue working on this, that gets me very excited.

[dkarlovi]

I have a rather complex Symfony app (WIP, also ApiPlatform) in Docker: development with Docker Compose, deployment to Openshift / Kubernetes, support for environments, a lot of tweaks per each image for example, my app image allows for XDebug on development but it's disabled on production (using the exact same image, different runtime environment) or uses the same image for web app server (PHP-FPM) and async CLI-workers (Console + Enqueue bundle) which, if in development, monitor the src/ folder for changes and auto-restart the workers.

From that experience, it shouldn't be too hard to get a pretty good all-around config, but the problem would be how to allow for extendability as you currently can't extend Dockerfiles (you can extend Docker Compose file, that's how I get the per-environment settings), it would be a run-once deal.

[teohhanhui]

I don't believe Symfony Flex should create services in the Docker Compose file (or its equivalent in other container orchestration systems).

But we really need a "developer story" to understand what's the experience like using Symfony Flex with Docker. I believe that for Symfony Flex to be successful, it really needs to treat Docker as a first-class citizen (and this is the perfect opportunity to ensure that is the case). I've just started trying it out...

[andrerom]

First, @dkarlovi nice work on https://github.com/dkarlovi/symfony-flex-docker, healthcheck and all.

As for extensibility there are a few things we can potentially use here:

• Recipes can be allowed to specify either php extensions to enable (among the once in php source), or to install via pecl
  • (One blocker here, pecl is not able to pick latests version of for instance memcached on PHP 5.6, you'll have to specify version for that. Not saying we care about php 5.6, but the same issue will come back at any point there is sufficient breaks in php again for extensions)
• Recipes can provide own services, we can use docker composes support for being able to stack several files after each other (also supported by COMPOSE_FILE env variable that can be set in .env)
  • This is not without down sides, makes running the thing more complex, but for example see, and
• Makefile with abstraction / simplification for docker use
• Symfony Flex generating .env file for the result, including COMPOSE_FILE, and providing build arguments to app container for php extensions

[dunglas]

@andrerom I'll open a PR on Flex soon adding the ability to update docker-compose.yaml and the Dockerfile from a recipe.

I've also created a new installer for Flex using Docker: https://github.com/dunglas/symfony-docker-skeleton/tree/autoinstall

[teohhanhui]

the ability to update docker-compose.yaml and the Dockerfile from a recipe.

As long as it is strictly opt-in only.

[dkarlovi]

@andrerom

First, @dkarlovi nice work on https://github.com/dkarlovi/symfony-flex-docker

Thanks,

I'm thinking more in line of:

1. creating a utility which is able to emit a valid Dockerfile while being configured programmatically
2. setup the base symfony-flex-docker repo to allow for placing configuration for 1) in with a classic .d notation
3. split the base repo into sub-repos which would add their specific fragments into those .d folders (this would allow say symfony-flex-docker-mysql to request the app image to support pdo_mysql, for example, or similar)
4. rebuilding the base Dockerfile and the base app image when required

It seems like it would go a long way.

[dkarlovi]

the ability to update docker-compose.yaml and the Dockerfile from a recipe

Also not a fan of this, TBH.

[joelwurtz]

the ability to update docker-compose.yaml and the Dockerfile from a recipe

Not a fan either as i think docker-compose is a too higher level of abstraction for that.

IMO we should build something that use directly the Docker API so it will be easier to maintain and also we would have more capabilites and better integration with Docker.

[dkarlovi]

use directly the Docker API

This is a wrong level of abstraction, IMO. You'd need to figure out how to hook into stuff like Kubernetes / OpenShift / other solutions which already do this so you end up between a rock and a hard place. While, using Compose, you get to use more established tools like Kompose.

[dunglas]

My prototype is almost working. Please wait for it and the related blog post to make an opinion.

Kubernetes support is a must have (it will come). But Docker-compose is shipped with most Docker installations. It will allow to manage the lyfecycle of a Symfony project from installation to production and during all the development cycle.

In term of DX, it will be a game changer, and definitely better than Vagrant, Homestead and other WAMP.

[Aerendir]

@dunglas , did you publish the blog post you cited in your comment? Where is it? I'd like to read it to understand better Docker use with Symfony other than the code in the repo you are working on... Thank you!

[teohhanhui]

The closest thing for now is https://github.com/api-platform/api-platform