• 生成邮件相关文件

rails g mailer UserMailer accout_activation password_reset

• 开发环境中的邮件配置
  config/environments/development.rb

config.action_mailer.raise_delivery_errors = true
config.action_mailer.delivery_method = :test
host = 'localhost:3000'
config.action_mailer.default_url_options = {host: host}

• controller
  app/mailers/application_mailer.rb

class ApplicationMailer < ActionMailer::Base
  default from: "from@example.com"
  layout 'mailer'
end

app/mailers/user_mailer.rb

class UserMailer < ApplicationMailer
  # Subject can be set in your I18n file at config/locales/en.yml
  # with the following lookup:
  #
  #   en.user_mailer.account_activation.subject
  #
  def account_activation user
    @greeting = "Hi"
    @user = user

    mail to: user.email, subject: "Account activation"
  end

  # Subject can be set in your I18n file at config/locales/en.yml
  # with the following lookup:
  #
  #   en.user_mailer.password_reset.subject
  #
  def password_reset user
    @greeting = "Hi"
    @user = user
    mail to: user.email, subject: "Password reset"
  end
end

这样就可以在controllers/models/views通过调用account_activation(user)来发送邮件

UserMailer.account_activation(User.first).deliver_now

• view
  在发邮件之前，需要先渲染出邮件的内容，邮件有两个模板视图：html和text。与其它的views视力一样，也可以在邮件的视图中使用嵌入式ruby。

app/views/usermailer/account_activation.html.erb

<p>
  <%= "#{@greeting}, #{@user.name}" %>
  Welcome! Click on the link below to activate your account:
</p>

<%= link_to "Activate", edit_account_activation_url(@user.activation_token, email: @user.email)  %>

or copy the link below

<%= edit_account_activation_url(@user.activation_token, email: @user.email)  %>

app/views/usermailer/account_activation.text.erb

<%="#{@greeting}, #{@user.name}" %>
Welcome! Click on the link below to activate your account:
<%= edit_account_activation_url(@user.activation_token, email: @user.email)  %>

• 预览邮件内容
  test/mailer/preview/user_mailer_preview.rb

# Preview all emails at http://localhost:3000/rails/mailers/user_mailer
class UserMailerPreview < ActionMailer::Preview

  # Preview this email at http://localhost:3000/rails/mailers/user_mailer/account_activation
  def account_activation
    user = User.first
    user.activation_token = User.new_token
    UserMailer.account_activation(user)
  end

  # Preview this email at http://localhost:3000/rails/mailers/user_mailer/password_reset
  def password_reset
    user = User.first
    user.password_reset_token = User.new_token
    UserMailer.password_reset(user)
  end

end

注意其中的两行：

# Preview this email at http://localhost:3000/rails/mailers/user_mailer/account_activation
# Preview this email at http://localhost:3000/rails/mailers/user_mailer/password_reset

只需要复制http://localhost:3000/rails/mailers/user_mailer/account_activation就可以预览邮件内容了