[ECS] Remove dependency on symfony/http-kernel

[TomasVotruba]

The symfony/http-kernel is a useful package to quickly bootstrap project using Symfony DI.
The disadvantage is that it will many heavy Symfony framework components

• http-foundation
• error-handler
• var-dumper
• cache
• event-dispatcher

etc.
We only need to build Dependency Injection container. But unfortunately, there is no component that would only create container from configs. The Dependency Injection component is just a simple package for handling mostly service value object. The container itself is built unfortunately in http-kernel component.

Ideally the container-builder should be separated from http-kernel, that would be light and only build the container. Due to this heavy Symfony pull, all Symplify CLI packages are almost as heavey as any MVC framework application. Imagine PHPUnit using full symfony/symfony, that's not good.

As negative consequence, the downgrade process is slow, heavy and the download of simple ECS results in download of dozens unused Symfony components, just to make http-kernel happy.

To avoid this, this is an attempt to build the missing container-builder package, that only accepts:

• extensions
• compiler passes
• configs paths

And returns compiled Container in the end. Will it work? :)

[TomasVotruba]

cc @matthiasnoback Hi Matthias, I had a struggle with too heavy Symfony, so I've decided to drop anything we don't need from Symfony to build the container. I think you might like this one.

Any feedback appreciated!

Also, if this work, it might get to Rector itself :)

[TomasVotruba]

-390 files 🥳

It took a while to clean whole symplify dependency tree from symfony/http-kernel, but the results are here :)

https://twitter.com/VotrubaT/status/1455104311478951936

[TomasVotruba]

How much ECS vendor lose weight?

phploc vendor before

Directories                                        504
Files                                             2326


Size
  Lines of Code (LOC)                           263771
  Comment Lines of Code (CLOC)                   91989 (34.87%)
  Non-Comment Lines of Code (NCLOC)             171782 (65.13%)
  Logical Lines of Code (LLOC)                   61606 (23.36%)

Classes                                         2056

phploc vendor after

Directories                                        436
Files                                             1974

Size
  Lines of Code (LOC)                           225756
  Comment Lines of Code (CLOC)                   78870 (34.94%)
  Non-Comment Lines of Code (NCLOC)             146886 (65.06%)
  Logical Lines of Code (LLOC)                   52923 (23.44%)

Classes                                         1768