[DRAFT] 4.x Refactor Routing

[l0gicgate]

This is a draft proposal to refactor all routing components as per issue #2583.

The proposed changes introduce the following interfaces:

• RouteCollectorInterface: Collects all routes and groups, handles cache file
• RouteCollectorProxyInterface: This interface is what the App components extends and also what is being passed into RouteGroup. We will not be exposing all of App's methods when instantiating a RouteGroup instead this proxy interface handles communication with the RouteCollector
• RouteInterface stays the same, minor change is that we have gotten rid of Routable all together
• RouteGroupInterface this interface now has a collectRoutes() method which helps us get rid of the old RouteGroup::__invoke(), Router::pushGroup() and Router::popGroup() methods. RouteCollectorProxy has the ability to have a base path which will append it to all the patterns being passed via the proxy methods get(), put(), post(), etc. while collecting the routes from inside the RouteGroup's callable
• RouteResolverInterface this component is very simple and its only concerns are to create the FastRoute dispatcher, dispatch the ServerRequestInterface to it and return the computed RoutingResults via the RouteResolverInterface::computeRoutingResults() method. This interface also has the responsibility to resolve the appropriate route communicating with RouteCollector to achieve that. RoutingMiddleware uses this resolver to perform the routing.

Deprecated Components/Methods

• Router and RouterInterface are now gone since they've been effectively separated
• Routable does not exist anymore as it has been merged into Route since it is the only component that was using those methods
• RouteGroup does not hold a $pattern variable anymore as it is unnecessary due to the state of the pattern residing inside RouteCollectorProxy when collecting the inner routes of a group
• Route::finalize() does not exist anymore, it has effectively been merged with Route::prepare()
• RouteDispatcher has been renamed to RouteRunner since that's all it does, it calls Route::run()

New Namespace Folder
New namespace folder called Routing which has all of the routing components.

This PR will be separated into smaller ones

• Decouple RouteGroup & Route from Routable - 4.x Refactor RouteGroup & Route #2612 Merged
• Decouple Router into RouteCollector and RouteResolver - 4.x - Split RouterInterface into RouteCollectorInterface and RouteResolverInterface #2622 Merged
• Add Route::setInvocationStrategy() to RouteInterface - 4.x - Route InvocationStrategy Setter #2634 Merged
• Add RouteCollector::fullUrlFor() as per Rewrite Router->urlFor() to generate complete Urls #2493 - 4.x - Port RouteCollector::fullUrlFor() #2638 Merged
• Introduce DispatcherInterface to decouple from FastRoute Dispatcher - 4.x - Decouple FastRoute Dispatcher From RouteResolver #2639 Merged
• Introduce RouteParserInterface to decouple from FastRoute RouteParser - 4.x - Decouple FastRoute RouteParser #2640 Merged
• Introduce RouteCollectorProxy - 4.x - RouteCollectorProxy #2641 & 4.x - Refactor RouteCollectorProxy #2642 Merged

[l0gicgate]

@bnf I would like your input on this when you get a minute. Thank you!

[akrabat]

This is in danger of being too big. Can we pull out some bits into their own PRs?