将所有文件从子文件夹递归移动到父文件夹(Moving all files recursively from subfolders to parent)

 deliver方法，应在Mailer方法中调用。 但不是使用deliver ，而是使用deliver_now或deliver_later 。 
 
 将您的控制器更改为： 
 
def create
    FamilyMailer.notify_family_member(FamilyMember.last).deliver_now
end
 
 和你的邮件： 
 
class FamilyMailer < ApplicationMailer
  default from: "Gold<contact@goldyo.me>"
  def notify_family_member(family_member)
    puts "in the mailer"
    mail(to: family_member.email, subject: "Photos")
  end
end

The deliver method, should be called at the Mailer method. But instead of using deliver, use deliver_now or deliver_later.
 
Change your controller to:
 
def create
    FamilyMailer.notify_family_member(FamilyMember.last).deliver_now
end
 
And your mailer:
 
class FamilyMailer < ApplicationMailer
  default from: "Gold<contact@goldyo.me>"
  def notify_family_member(family_member)
    puts "in the mailer"
    mail(to: family_member.email, subject: "Photos")
  end
end