nginx The plain HTTP request was sent to HTTPS port

当使用nginx部署前端应用并将http访问转为https访问时，有时会出现"The plain HTTP request was sent to HTTPS port"的错误页面。这个错误的原因是客户端发送了一个普通的HTTP请求到了配置为HTTPS监听的端口上。解决这个问题的思路是将http的请求重定向到https。可以在nginx的配置文件中添加以下代码来实现重定向：

server {
    listen 80;
    listen 443 ssl;
    ssl_certificate ssl_cert.pem;
    ssl_certificate_key ssl_server.key;
    server_name your_domain.com;
    
    if ($scheme = http) {
        return 301 https://$host$uri?$args;
    }
    
    location / {
        ....
    }
}

这样配置后，当客户端发送http请求时，nginx会自动将其重定向到https，从而解决"The plain HTTP request was sent to HTTPS port"的错误页面问题。