[4.x] Add method to customize the response factory class in the slim http psr17 factory

[adriansuter]

This PR addresses #2712.

[coveralls]

Coverage remained the same at 100.0% when pulling 95a2ea2 on adriansuter:patch-responseFactoryClass into 0594fb8 on slimphp:4.x.

[adriansuter]

How would we be able to set a custom http decorator?

[l0gicgate]

You'd need to create your own ResponseFactory then use AppFactory::setResponseFactory($yourCustomFactory)

Then create your own ServerRequestCreator and do ServerRequestCreatorFactory::setServerRequestCreator($yourCustomServerRequestCreator).

[adriansuter]

Wouldn't it be nice, that if you use one of the built-in PSR-7 implementations, then you just have to set the custom http decorator response factory to the slim http psr17 factory? Then Slim does automatically decorate as before.

[l0gicgate]

How many decorator libraries are there for PSR-7 decoration besides Slim-Http? I don't know of any.

[adriansuter]

Agree. So you think that this should not be an option? Either you use Slim-Http or you have to create your own response factory and server request creator.

[l0gicgate]

If we were to do it correctly, we'd need to create a decorator provider specifically for that purpose. Opening up the SlimHttp provider with that setter just seems like a hackish way to do it. So for now, unless users end up requesting that feature I don't think it's necessary.