This is a new feature for the Messenger component which is why there is no issue ticket attached.

Currently, HandlersLocator extracts message class along with all parent classes and all interfaces + a '*' wildcard to match any transport.
This is not fully efficient resulting in many routes for messages that share the same transport but by design don't share any inheritance or interface.

This is an opportunity to introduce simple wildcards which allow defining a transport for multiple messages grouped in one namespace.
For eg. given a bunch of messages acting as commands, queries, and events (in CQRS)

• App\Message\Command\CreatePost
• App\Message\Command\PublishPost
• App\Message\Event\PostCreated
• App\Message\Event\PostPublished
• App\Message\Query\FindPost

The intention may be to send all Commands to async transport, Queries to sync transport but Events to a different transport for eg. stream - the configuration requires creating routing for at least 3 classes because none of them share inheritance or interfaces with one wildcard '*' for async or sync as these are the most numerous.

framework:
    messenger:
        routing:
            App\Message\Command\CreatePost: async
            App\Message\Command\PublishPost: async
            App\Message\Query\FindPost: sync
            '*': stream

With this feature managing, multiple types of transport allow us to ultimately define 3 wildcarded namespaces instead and reduce the maintenance burden at the same time and prevent using standalone '*' which unconsciously may be the cause of problems. The configuration using namespace wildcards will look as follows:

framework:
    messenger:
        routing:
            App\Message\Command\*: async
            App\Message\Event\*: stream
            App\Message\Query\*: sync
#            '*': stream

The aim of this PR is to provide a simple solution supporting wildcards in routing to prevent using '*'. In future scope, matching rules may be the subject of another PR addressing improvements in the future.