Add Events support for Command

[alecslupu]

🎩 What? Why?

In the review of #10151, @ahukkanen suggested to use a hook method in the commands so that we can easily issue ActiveSupport Notifications that can be subscribed to from various places of Decidim application. While implementing this, i have seen that we already have some other events that we dispatch, so, in order to have a consolidated mode of issuing application wide events, i have created this PR.

📌 Related Issues

Link your PR to an issue

• Related to Use content classification systems for better SPAM detection #10151
• Related to Detect the use of spam-bots and ban non compliant users (part 2) #6804
• Related to Add direct action to block this participant #10111

Testing

Follow the test scenarios in #6804 and #10111

♥️ Thank you!

[ahukkanen]

I have gone through the code as well as tested this by adding the following initializer code in the development application:

log_path = Rails.root.join("log/testing_events.log")
logger = Logger.new(log_path)

logger.info("Started the application!")

Decidim::EventsManager.subscribe("decidim.admin.block_user:before") do |event_name, data|
  logger.info("Block user -- BEFORE")
  logger.info(event_name.inspect)
  logger.info(data.inspect)
end

Decidim::EventsManager.subscribe("decidim.admin.block_user:after") do |event_name, data|
  logger.info("Block user -- AFTER")
  logger.info(event_name.inspect)
  logger.info(data.inspect)
end

It worked great and logged both events when I blocked a user.

Overall I really like the approach, I have just left a couple of comments regarding some code clarification and regarding the with_events method itself which I think could be simplified.

[ahukkanen]

Just one more remark and this is good to go for me.

There may be a reason for this but I didn't understand it.