Module: Hecks::Runtime::CommandRules::Emission

Included in:
Hecks::Runtime::CommandRules
Defined in:
lib/hecks/runtime/command_rules/emission.rb

Overview

What a command's emits becomes: an Event in the registry's log, and — where the store can hold one — a recorded event beside the data it describes.

Instance Method Summary collapse

Instance Method Details

#emit(command, domain, aggregate, instance, args, repository, correlation = nil) ⇒ Object

correlation arrives HERE rather than being merged onto the event afterwards. It is part of the transaction — known from dispatch's own argument before anything is emitted — and an event that is still being written to is not yet a record of what happened. Setting it at construction is what lets the event be frozen the moment it exists.



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# File 'lib/hecks/runtime/command_rules/emission.rb', line 16

def emit(command, domain, aggregate, instance, args, repository, correlation = nil)
  command.emits.map do |event_name|
    event = Event.new(
      name:        event_name,
      aggregate:   "#{domain}::#{aggregate.hecks_name}",
      id:          instance.id,
      payload:     args,
      occurred_at: Time.now.utc.iso8601,
      correlation: correlation
    )
    @registry.event_log << event.emit!
    repository.record_event(event) if repository.respond_to?(:record_event)
    event
  end
end