将HTTP重定向到HTTPS时如何处理Nginx中的400错误

我拥有一个网站，比如HTTP的example.com。考虑到安全性，现在我想将HTTP更改为HTTPS。我希望所有老客户都能访问我的网站，即使他们使用example.com，它将通过Nginx重定向到https

当然，我搜索了很多，然后我的解决方案是：

upstream www {
  server 127.0.0.1:4000;
}
server {
  listen      80;
  listen      443 ssl;
  server_name localhost www example.com;

  ssl on;
  ssl_certificate  /usr/local/etc/docs/example.crt;
  ssl_certificate_key  /usr/local/etc/docs/example.key;

  if ($ssl_protocol = "") {
    rewrite ^ https://$host$request_uri? permanent;
  }

  # below are some other stuff
  # ...
}

但当我访问example.com时，我发现：

400错误请求普通HTTP请求已发送到HTTPS端口

然后，我在读取后更改nginx.conf，并通过497配置错误页面：

upstream www {
  server 127.0.0.1:4000;
}
server {
  listen      80;
  listen      443 ssl;
  server_name localhost www example.com;

  ssl on;
  ssl_certificate  /usr/local/etc/docs/example.crt;
  ssl_certificate_key  /usr/local/etc/docs/example.key;

  error_page 497  https://$host$request_uri;

  # below are some other stuff
  # ...
}

然后它工作了，一切都很好。但我只是不知道为什么，错误页面的解决方案似乎是错误的。所以 阅读之后，我添加了默认值并删除了上的ssl

upstream www {
  server 127.0.0.1:4000;
}
server {
  listen      80;
  listen      443 default ssl;
  server_name localhost www example.com;

  ssl on;
  ssl_certificate  /usr/local/etc/docs/example.crt;
  ssl_certificate_key  /usr/local/etc/docs/example.key;

  if ($ssl_protocol = "") {
    rewrite ^ https://$host$request_uri? permanent;
  }

  # below are some other stuff
  # ...
}

太好了！它又起作用了。但我不确定：

• 哪种解决方案是正确的？
• 如果两者都正确，哪一个对SEO更友好？

---

解决方案1是真正有线的，从中可以发现永久重定向更友好

server {
    listen 80;
    server_name www.example.com;
    return 301 https://$host$request_uri;
}


server {

  listen      443 default ssl;
  server_name  www example.com;

  ssl on;
  ssl_certificate  /usr/local/etc/docs/example.crt;
  ssl_certificate_key  /usr/local/etc/docs/example.key;



  # below are some other stuff
  # ...
}