关于$body_bytes_sent的问题

xiemingqiang1114 · 2016-06-02T15:33:14+00:00

乱码与gzip应该没有关系。 http { include mim...

关于$body_bytes_sent的问题

xiemingqiang1114

请教agentzh一个关于$body_bytes_sent的问题

我的openresty配置如下

http {

include mime.types;

default_type application/octet-stream;

log_format json '{"@timestamp":"$time_local",'

'"@fields":{'

'"ip":"$remote_addr",'

'"cache":"$upstream_cache_status",'

#'"req":"$request_body",'

'"req":"$request",'

'"key":"$arg_key",'

'"status":$status,'

'"resbytes":$body_bytes_sent,'

'"reqtime":$request_time}}';

access_log logs/access.log json;

server {

listen 8081;

server_name 127.0.0.1;

location / {

access_log off;

content_by_lua_file '/usr/local/openresty/luaframework/luasrc/mch/localcache.lua';

}

location /@cacheredis {

log_subrequest on;

echo 'this is my test string - dsddddddddddddddddddddddddddddddd';

#proxy_cache my_cache;

#proxy_cache_revalidate on;

#proxy_cache_key $arg_key;

#proxy_cache_valid 200 304 302 10m;

#proxy_cache_methods GET HEAD POST;

#proxy_cache_min_uses 3;

#proxy_cache_use_stale error timeout updating http_500 http_502 http_503 http_504;

#proxy_cache_lock on;

#proxy_pass http://127.0.0.1:8082;

}

/usr/local/openresty/luaframework/luasrc/mch/localcache.lua的代码如下:

local res = ngx.location.capture("/@cacheredis", { method = ngx.HTTP_POST, body = ngx.var.request_body})

ngx.say(res.body)

我用curl -X POST --data "data="" http://127.0.0.1:8081请求能正常返回this is my test string - dsddddddddddddddddddddddddddddddd

我的access.log记录如下

{"@timestamp":"02/Jun/2016:15:26:47 +0800","@fields":{"ip":"127.0.0.1","cache":"-","req":"POST / HTTP/1.1","key":"-","status":200,"resbytes":0,"reqtime":0.000}}

我的问题是，为什么resbytes即$body_bytes_sent一直是0呢？

agentzh

Hello!

On Thu, Jun 2, 2016 at 12:33 AM, 谢明强 wrote:
> 我的access.log记录如下
> {"@timestamp":"02/Jun/2016:15:26:47
> +0800","@fields":{"ip":"127.0.0.1","cache":"-","req":"POST /
> HTTP/1.1","key":"-","status":200,"resbytes":0,"reqtime":0.000}}
> 我的问题是，为什么resbytes即$body_bytes_sent一直是0呢？

你这个是子请求的访问日志记录吧？子请求的响应被 ngx.location.capture 给捕获住了，而 $body_bytes_sent
是发送到客户端的请求体字节数，显然子请求本身没有任何数据发送给客户端，所以 $body_bytes_sent 的值自然总是为 0
了。你可以在 log_format 里面加入 $uri?$args 字段，这样你可以区分主请求和子请求。$request
的值永远是主请求，即使在子请求中引用。

考虑下面这个最小化的例子：

log_format custom "$request - $uri?$args bytes sent: $body_bytes_sent";
server {
    listen 8080;
    access_log logs/access.log custom;
    location = /t {
        content_by_lua_block {
            local res = ngx.location.capture("/@cacheredis")
            ngx.say(res.body)
        }
    }

    location /@cacheredis {
        log_subrequest on;
        echo "This is my test string";
    }
}

访问一次 /t 会得到下面这两行访问日志记录：

GET /t HTTP/1.1 - /@cacheredis?- bytes sent: 0
GET /t HTTP/1.1 - /t?- bytes sent: 35

我们看到子请求里的 $request 值还是主请求的。同时子请求的 bytes sent 确实是 0，而主请求的 bytes sent
并不为 0，而是 35，正是我们期望的。

Regards,
-agentzh

xiemingqiang1114

明白了，春哥！

在 2016年6月2日星期四 UTC+8下午3:33:14，谢明强写道：

请教agentzh一个关于$body_bytes_sent的问题
我的openresty配置如下
http {
include mime.types;
default_type application/octet-stream;

log_format json '{"@timestamp":"$time_local",'
'"@fields":{'
'"ip":"$remote_addr",'
'"cache":"$upstream_cache_status",'
#'"req":"$request_body",'
'"req":"$request",'
'"key":"$arg_key",'
'"status":$status,'
'"resbytes":$body_bytes_sent,'
'"reqtime":$request_time}}';

access_log logs/access.log json;

server {
listen 8081;
server_name 127.0.0.1;

location / {
access_log off;
content_by_lua_file '/usr/local/openresty/luaframework/luasrc/mch/localcache.lua';
}

location /@cacheredis {
log_subrequest on;
echo 'this is my test string - dsddddddddddddddddddddddddddddddd';
#proxy_cache my_cache;
#proxy_cache_revalidate on;
#proxy_cache_key $arg_key;
#proxy_cache_valid 200 304 302 10m;
#proxy_cache_methods GET HEAD POST;
#proxy_cache_min_uses 3;
#proxy_cache_use_stale error timeout updating http_500 http_502 http_503 http_504;
#proxy_cache_lock on;
#proxy_pass http://127.0.0.1:8082;

}

/usr/local/openresty/luaframework/luasrc/mch/localcache.lua的代码如下:

local res = ngx.location.capture("/@cacheredis", { method = ngx.HTTP_POST, body = ngx.var.request_body})
ngx.say(res.body)

我用curl -X POST --data "data="" http://127.0.0.1:8081请求能正常返回this is my test string - dsddddddddddddddddddddddddddddddd
我的access.log记录如下
{"@timestamp":"02/Jun/2016:15:26:47 +0800","@fields":{"ip":"127.0.0.1","cache":"-","req":"POST / HTTP/1.1","key":"-","status":200,"resbytes":0,"reqtime":0.000}}
我的问题是，为什么resbytes即$body_bytes_sent一直是0呢？