Caching 如何为gunicorn夹层启用nginx代理缓存

我们的堆栈是在EC2实例上运行的nginx-gunicorn-mezzanine（django cms）。一切正常，但我似乎无法启用nginx proxy\u缓存。以下是我的最低配置：

upstream %(proj_name)s {
    server 127.0.0.1:%(gunicorn_port)s;
}

proxy_cache_path /cache keys_zone=bravo:10m;

server {
    listen 80;
    listen 443;
    server_name %(live_host)s;
    client_max_body_size 100M;
    keepalive_timeout 15;

    location /static/ {
        expires 1M;
        access_log off;
        add_header Cache-Control "public";
        root %(proj_path)s;
    }

    location / {
        expires 1M;
        add_header X-Proxy-Cache $upstream_cache_status;
        proxy_cache bravo;
        proxy_ignore_headers Cache-Control Expires Set-Cookie;

        proxy_redirect off;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-Protocol $scheme;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

        proxy_pass http://%(proj_name)s;
    }
}

样本响应：

HTTP/1.1 200 OK
Server: nginx/1.4.6 (Ubuntu)
Date: Wed, 07 Jan 2015 03:43:47 GMT
Content-Type: text/html; charset=utf-8
Transfer-Encoding: chunked
Connection: keep-alive
Vary: Accept-Encoding
Vary: Cookie, Accept-Language
Content-Language: en
Expires: Fri, 06 Feb 2015 03:43:47 GMT
Cache-Control: max-age=2592000
X-Proxy-Cache: MISS
Content-Encoding: gzip

我启用了夹层缓存中间件，它将返回带有设置Cookie头的响应，但proxy\u ignore\u头应该忽略这一点

我在proxy\u cache\u path dir（/cache）上执行了chmod 777，所以这不应该是权限问题

错误日志记录已启用，但未生成任何内容

代理缓存路径

继续保持完全空

为什么nginx不使用此配置缓存任何内容？