如何在Django的Anymail中使用Postmark批量发送邮件？

你遇到的循环逐个发送超时问题，核心是同步请求阻塞了页面响应，同时没利用Postmark的批量API能力。下面给你两种可行的解决思路：

一、用Anymail批量API一次性发送多封独立邮件 #

Postmark支持单次API请求发送最多500封独立邮件（每个收件人单独收到，无抄送/密送），Anymail封装了这个能力，比循环逐个发送效率高得多。

基于你现有代码改造的示例：

from anymail.message import AnymailMessage
from django.core.mail import get_connection

# 准备你的收件人列表、邮件内容等参数
recipient_list = ["user1@example.com", "user2@example.com", ...]
subject = "统一主题"
plain_text_body = "纯文本内容"
html_body = "<p>HTML格式的邮件内容</p>"
sender_email = "your-sender@domain.com"
message_stream = "your-postmark-stream"

# 批量构建邮件实例，每个实例对应一个收件人
messages = []
for to_addr in recipient_list:
    msg = AnymailMessage(
        subject=subject,
        body=plain_text_body,
        from_email=sender_email,
        to=[to_addr],  # 每个邮件只填一个收件人
    )
    msg.attach_alternative(html_body, "text/html")
    msg.esp_extra = {'MessageStream': message_stream}
    messages.append(msg)

# 一次性发送所有邮件
with get_connection() as conn:
    conn.send_messages(messages)

注意：Postmark单次批量请求最多支持500封邮件，如果你的收件人超过这个数，记得把列表拆分成多个500以内的批次分别发送。

二、异步发送彻底解决页面超时 #

如果收件人数量极大，哪怕用批量API，同步执行还是会占用请求时间导致超时。这时候把发送任务放到后台异步执行是最优解，推荐用Celery（Django生态最常用的异步任务队列）。

1. 编写异步发送任务 #

在你的app下创建tasks.py：

from celery import shared_task
from anymail.message import AnymailMessage
from django.core.mail import get_connection

@shared_task
def batch_send_emails(recipients, subject, plain_body, html_body, sender, stream):
    messages = []
    for to_addr in recipients:
        msg = AnymailMessage(
            subject=subject,
            body=plain_body,
            from_email=sender,
            to=[to_addr],
        )
        msg.attach_alternative(html_body, "text/html")
        msg.esp_extra = {'MessageStream': stream}
        messages.append(msg)
    
    with get_connection() as conn:
        conn.send_messages(messages)

2. 在视图中触发异步任务 #

把原来的同步发送代码改成调用异步任务，这样页面会立即返回，任务在后台执行：

from django.http import HttpResponse
from .tasks import batch_send_emails

def trigger_email_send(request):
    # 这里可以从请求或数据库获取收件人列表等参数
    recipient_list = ["user1@example.com", "user2@example.com"]
    subject = "异步批量邮件测试"
    plain_body = "纯文本内容"
    html_body = "<h2>异步发送的HTML邮件</h2>"
    sender = "your-sender@domain.com"
    stream = "your-postmark-stream"

    # 调用异步任务，用delay()方法提交到Celery队列
    batch_send_emails.delay(recipient_list, subject, plain_body, html_body, sender, stream)

    return HttpResponse("邮件发送任务已提交，后台处理中")

3. 启动Celery Worker #

最后要启动Celery worker来处理后台任务：

celery -A your_django_project_name worker --loglevel=info

关键配置检查 #

确保你的settings.py中Anymail和Postmark的配置正确：

ANYMAIL = {
    "POSTMARK_SERVER_TOKEN": "你的Postmark服务器密钥",
}
EMAIL_BACKEND = "anymail.backends.postmark.EmailBackend"

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