Add support for Action Cable

[xlts]

Refactor log subscribers & create a new one to support logging of Action Cable events

Monkey-patch Action Cable server class to silence default Action Cable logger

Monkey-patch Action Cable Channel and Connection classes to support logging subscribe, unsubscribe, connect & disconnect events

Update log formatters to support Action Cable log data

[xlts]

Two important remarks here:

1. I decided to silence the default Action Cable logger (defined in ActionCable::Server::Base) completely - the framework code is littered with multiple logger calls in plenty of classes. Monkey-patching it would be utterly painful and could leave the code extremely hard to maintain in case of a change in Action Cable itself. As a consequence, calling logger e.g. in user-defined Connection or Channel classes has no effect - a Rails.logger has to be used instead. Should this solution be accepted, we'd probably need to include a post-install message informing the developer about this state of things.

2. Obviously Action Cable doesn't include a notion of a "controller", however for simplicity I decided to use this name to indicate both Channel or Connection classes in formatters. So if e.g. a pong action defined in MyChannel < ActionCable::Channel::Base is called, the Graylog log message would include the following: MyChannel#pong and the key of MyChannel value in Lograge data hash is still called controller.

[benlovell]

Thanks. This looks good at first glance - I'll give it a proper review over the weekend.

[xlts]

Thx @benlovell. Let me know if anything needs explaining

[nfedyashev]

@benlovell is there anything missing?

@xlts thanks for your work btw!

[xlts]

Thanks @nfedyashev! @benlovell are there chances of having this reviewed anytime soon?

[benlovell]

Thanks for this. Sorry for the delay! I’ll cut a release today or tomorrow. 💖

[xlts]

Cool! In the next few days I'll try to work on updates to Readme so that we have this documented & explained properly.

[benlovell]

Thanks <3

…

On Mon, 15 Apr 2019 at 21:10, Mariusz Hausenplas ***@***.***> wrote: Cool! In the next few days I'll try to work on updates to Readme so that we have this documented & explained properly. — You are receiving this because you modified the open/close state. Reply to this email directly, view it on GitHub <#257 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AACj6zIAa16i8hKMyAbolnfbPYettEBCks5vhNzCgaJpZM4WP_3H> .

[jwhitcraft]

Because of the Monkey-patch it breaks AnyCable see #294

[palkan]

Because of the Monkey-patch it breaks AnyCable see #294

Not only AnyCable is affected, Action Cable's functionality is also changed, compare these two lines, for example:
lograge

lograge/lib/lograge/rails_ext/action_cable/connection/base.rb

Line 16 in 1729eab

respond_to_invalid_request

rails https://github.com/rails/rails/blob/a11e63f39907f828986f1832329c1b0530ca2aa3/actioncable/lib/action_cable/connection/base.rb#L178

@xlts @benlovell Please, consider replacing this MP with the one not-related on the internal implementation (e.g., using Module#prepend) and/or propose the required changes to Rails (I would be glad to help with making it merged).

@jwhitcraft A quick-fix should be smth like:

Lograge.class_eval do
  def self.attach_to_action_cable; end
end