Class: Mbeditor::Engine

Inherits:
Rails::Engine
  • Object
show all
Defined in:
lib/mbeditor/engine.rb

Class Method Summary collapse

Class Method Details

.subscribe_to_exceptions ⇒ Object

Records controller exceptions into ExceptionLog and pushes them to any open editor over the existing cable channel.

process_action.action_controller rather than a Rack middleware: ActionDispatch::DebugExceptions rescues and renders the error, so nothing outside it ever sees the raise. Rails.error.subscribe would be a cleaner API but only carries unhandled request errors reliably on newer Rails, and this gem supports 7.1.



172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
 
# File 'lib/mbeditor/engine.rb', line 172

def self.subscribe_to_exceptions
  return if @exception_subscriber

  @exception_subscriber = ActiveSupport::Notifications.subscribe(
    "process_action.action_controller"
  ) do |_name, _started, _finished, _id, payload|
    # 5-arity: the block runs for every host request, and building an Event
    # just to read its payload allocated one per request for nothing.
    exception = payload[:exception_object]
    next unless exception

    entry = Mbeditor::ExceptionLog.record(
      exception, payload,
      workspace_root: Mbeditor::WorkspaceRootResolver.call
    )
    next unless entry && defined?(ActionCable.server)

    ActionCable.server.broadcast("mbeditor_editor", entry)
  rescue StandardError => e
    # A monitoring hook must never be able to break the request it observes.
    Rails.logger.debug("[mbeditor] exception capture failed: #{e.class}: #{e.message}")
  end
end