stephanschuler/docker-compose-schema

Create docker-compose via PHP

Creating docker-compose yaml files is very frustrating to me because the environment I'm at home lacks some support.

The language I am fluent in is PHP and there are plenty IDEs out there that understand PHP very well.

This package aims for providing reasonably strong typed PHP classes that are just JsonSerializable and create valid docker-compose.yaml files.

Current state of development

This package is not even close to be finished. I have some actual use cases to play with and I'm trying to cover those af first. But I do know there are a lot of things you can do with docker-compose that are not supported by this lib just because I haven't used them and didn't come around to put them in.

Handling still feels a bit columsy. Especially when some classes need to be created by the composition object for having back references while others are just value objects. And I'm kind of unhappy with the fluent interface currently suggesting immutability, which is definitively not the case.

Example

This could be a small docker-compose file:

version: "3.8"
services:
  web:
    image: "httpd:2.4"
    ports:
      - "8080:80"
      - "4443:443"
    networks:
      - my-network
    environment:
      - SOME_ENV_VAR=fooo
    links:
      - redis
  redis:
    image: "redis:alpine"
    networks:
      - my-network
networks:
  my-network:
    ipam:
      config:
        -
          subnet: 172.198.100.0/24

This is how it would be created in PHP:

<?PHP

$composition = Composition::create()
    ->withVersion('3.8');

$network = $composition->network('my-network');
$network
    ->withIpam(
        Ipam::create()
            ->withSubnet('172.198.100.0/24')
    );


$web = $composition->service('web');
$web
    ->fromImage(Image::create('http', '2.4'))
    ->withPort(Port::create(80)
        ->redirectedTo(8080))
    ->withPort(Port::create(443)
        ->redirectedTo(4443))
    ->withNetwork($network)
    ->withEnvironment(EnvironmentVariable::named('SOME_ENV_VAR')
        ->withValue('fooo'));

$redis = $composition->service('redis');
$redis
    ->fromImage(Image::create('redis', 'alpine'))
    ->withNetwork($network);

$web->withLinkedService($redis);

echo json_encode($composition, JSON_PRETTY_PRINT);

But why?

Obviously this way of doing things is a little bit more verbose. But honestly: I think that's a good thing. It feels a bit more expressive.

But the main reason is being able to pass around variables hand having them checked internally. Noticed the web service which is linked to the redis service somehwere at the bottom of the PHP code? Now my IDE makes sure I spell everything correctly and I only link things together that are actually already defined. Sure, I could have docker-compose tell me about that. But I prefer being helped and supported as soon as possible.

I minor thing I discovered when typing this little example: Maybe creating the web service as at first, defining the redis service afterwards and finally being able to link both together is a smell of thinking about the setup backwards.

And now think about loops and conditions and being able to create docker compose definitions really dynamically.

Epilogue:

I'm creating this package specifically in the light of one of my previous packages "stephanschuler/from-php". The goal is having PhpStorm call some docker-compose.yaml.php files and automatically create docker-compose.yaml files whenever changes to the .yaml.php file are made.