Nginx rewrite和proxy_pass解释

Question

我可以在 nginx/okd 配置中看到以下位置：

    location /STFlow/ {
        rewrite ^/STFlow(.*)$ $1 last;
#   
#          Are four lines below executed if rewrite has last option ???
#          What's the point of them?          
#
        proxy_pass http://zuul-proxy:8080; 
        proxy_set_header Host      $host;
        proxy_set_header X-Real-IP $http_x_forwarded_for;
        proxy_set_header X-Forwarded-For $http_x_forwarded_for;
    }

    location / {
        add_header debug-header dbg5;   
        set $realip $remote_addr;
        if ($http_x_forwarded_for ~ "^(\d+\.\d+\.\d+\.\d+)") {
            set $realip $1;
        }
        proxy_pass http://zuul-proxy:8080; 
        proxy_set_header Host      $host;
        proxy_set_header X-Real-IP $http_x_forwarded_for;
        proxy_set_header X-Forwarded-For $http_x_forwarded_for;
        client_max_body_size 50M;
    }

在location /STFlow/下面有四行rewrite ^/STFlow(.*)$ $1 last;执行过吗？

如果是什么时候？

它们的意义何在？

Answer 1

如果重写规则有一个break 标志而不是last，它会在将/STFlow/some/path URI 传递给上游之前删除/STFlow 前缀，即。 e.除了设置debug-header 和$realip 变量外，与第二个location 块相同。但据我了解，使用 last 标志会使这四行永远不会执行，进一步的 URI 处理将在第二个 location 块内完成。