wf example

base.rb

def accept_group_terms
  if current_entity.user? && notification.group_terms?
    if params[:terms_of_service][:checked]
      user_group = notification.entity.user_groups.with_user(current_entity).first
      if user_group
        user_group.terms_accepted_at = Time.now
        user_group.save
        notification.mark_as_read_by(current_entity).save!
        render_notif
      else
        render json: { errors: [ 'You are not allowed to answer this form' ] }, status: 422
      end
    else
      render json: { errors: [ 'You must accept the terms' ] }, status: 422
    end
  else
    render json: { errors: [ 'You cannot answer this form' ] }, status: 422
  end
end

wf.rb

def accept_group_terms
  Wf.new
    .when_falsy { current_entity.user? && notification.group_terms? }
      .dam { 'You cannot answer this form' }
    .when_falsy { params[:terms_of_service][:checked] }
      .dam { 'You must accept the terms' }
    .when_falsy { @user_group = notification.entity.user_groups.with_user(current_entity).first }
      .dam { 'You are not allowed to answer this form' }
    .chain {
      @user_group.terms_accepted_at = Time.now
      @user_group.save
      notification.mark_as_read_by(current_entity).save!
      render_notif      
    }
    .on_dam { |err| render json: { errors: [err] }, status: 422 }
end