SendGrid邮件发送正常但模板未加载问题求助

问题概述 #

SendGrid邮件可正常发送，但所有模板均无法加载，怀疑是代码调用逻辑问题，相关代码及日志如下：

控制器调用代码 #

AdminMailer.with( email: "xxxxxxxxx@gmail.com" , id:item.id, name: item.name, room: item.room.name).send_stock.deliver_later

AdminMailer实现代码 #

class AdminMailer < ApplicationMailer
  def send_stock
    mail(to: params[:email],
      subject: 'Foto sin inventario',
      body: 'email body',
      delivery_method_options: {
        api_key: ENV["SENDGRID_API"]
      },
      template_id: 'd-2d99d960ed47490497f1a99af32cd706', 
      dynamic_template_data:{
        'id': params[:id],
        'name': params[:name],
        'room': params[:room]
      }
    )
  end 

Rails输出日志 #

[ActiveJob] [ActionMailer::MailDeliveryJob] [d8927648-36ca-4e60-afd3-7fe6ea1b936f] Performing ActionMailer::MailDeliveryJob (Job ID: d8927648-36ca-4e60-afd3-7fe6ea1b936f) from Async(mailers) enqueued at 2022-09-29T22:08:22Z with arguments: "AdminMailer", "send_stock", "deliver_now", {:params=>{:email=>"xxxxxxxxx@gmail.com", :id=>4, :name=>"foto 3 exclusive", :room=>"Sala 1"}, :args=>[]}
[ActiveJob] [ActionMailer::MailDeliveryJob] [d8927648-36ca-4e60-afd3-7fe6ea1b936f] AdminMailer#send_stock: processed outbound mail in 1.0ms
[ActiveJob] [ActionMailer::MailDeliveryJob] [d8927648-36ca-4e60-afd3-7fe6ea1b936f] Delivered mail 6336175785e4_366932af97af0d39c27826@miguel.mail (7142.5ms)
[ActiveJob] [ActionMailer::MailDeliveryJob] [d8927648-36ca-4e60-afd3-7fe6ea1b936f] Date: Thu, 29 Sep 2022 17:08:23 -0500
From: xxxxxxxxx@gmail.com
To: xxxxxxxxx@gmail.com
Message-ID: <6336175785e4_366932af97af0d39c27826@miguel.mail>
Subject: Foto sin inventario
Mime-Version: 1.0
Content-Type: text/plain;
 charset=UTF-8
Content-Transfer-Encoding: 7bit
template-id: d-2d99d960ed47490497f1a99af32cd706
dynamic-template-data: {:id=>4, :name=>"foto 3 exclusive", :room=>"Sala 1"}

email body
[ActiveJob] [ActionMailer::MailDeliveryJob] [d8927648-36ca-4e60-afd3-7fe6ea1b936f] Performed ActionMailer::MailDeliveryJob (Job ID: d8927648-36ca-4e60-afd3-7fe6ea1b936f) from Async(mailers) in 7150.18ms

核心问题与修复步骤 #

1. 移除body参数 #

显式设置body会覆盖SendGrid模板的渲染逻辑，导致模板内容无法加载。删除body: 'email body'这一行，让SendGrid优先使用指定的动态模板。

修改后的send_stock方法：

def send_stock
  mail(to: params[:email],
    subject: 'Foto sin inventario',
    delivery_method_options: {
      api_key: ENV["SENDGRID_API"]
    },
    template_id: 'd-2d99d960ed47490497f1a99af32cd706', 
    dynamic_template_data:{
      'id': params[:id],
      'name': params[:name],
      'room': params[:room]
    }
  )
end 

2. 修正邮件内容类型 #

日志显示邮件Content-Type为text/plain，而动态模板通常为HTML格式，需显式指定内容类型为text/html，确保SendGrid正确解析模板：

mail(to: params[:email],
  subject: 'Foto sin inventario',
  content_type: 'text/html',
  delivery_method_options: {
    api_key: ENV["SENDGRID_API"]
  },
  template_id: 'd-2d99d960ed47490497f1a99af32cd706', 
  dynamic_template_data:{
    'id': params[:id],
    'name': params[:name],
    'room': params[:room]
  }
)

3. 验证模板与数据匹配 #

• 核对template_id是否与SendGrid控制台中的模板ID完全一致，注意保留d-前缀。
• 确认模板中使用的变量名（如{{id}}、{{name}}）与dynamic_template_data中的键完全匹配，区分大小写。

内容的提问来源于stack exchange，提问作者Msantamaria