Cable::Server#active_connections_for and Cable::Server#subscribed_channels_for public checkup methods

[rmarronnier]

From #85, this is a draft proposal PR investigating the best way for the backend to check what connection / channel are active for a given token (ie user).

The maze of different identifiers must make me oblivious to a simpler (ie more efficient than a rough #select == token) way to get the info we need.

I've added some DRY suggestions.

Right now, this is a draft, it lacks proper specs.

I'm working to add them but if you have DX / code design remarks / etc. please tell, I'm really new to this codebase (and websockets in general) !

[rmarronnier]

This PR is ready for review, but :

• I am not 100% convinced Cable need the two new public methods active_connections_for and subscribed_channels_for
  They don't exist in the ruby version (by the way, does cable-cr aim to mirror the action cable backend api ?), they might be misleading / misused when several Cable.server instances are spawn (most serious production cases ?).

That being said, writing these methods and the corresponding specs made me fix a bug (calling connection.close on a connection without channel subscriptions wasn't closing it), refactor some code and complete the server specs.

So, I won't fight for these methods as new public api if it "stalls" this PR as the rest of the code changes suggestions is more valuable IMO :-)

[rmarronnier]

We shouldn't return before closing the connection socket in the case of a connection without channel subscriptions.

[jwoertink]

Looks like there's a bit of refactoring going on in here, but it all looks good from what I see 👍 I left a comment, but otherwise I think this is good.

[rmarronnier]

Looks like there's a bit of refactoring going on in here, but it all looks good from what I see 👍 I left a comment, but otherwise I think this is good.

Thanks for the review :-)

[jwoertink]

🤦‍♂️ Ameba!!!! lol