Nginx 日志打印POST数据

在工作中，开发希望能从Nginx日志中获取POST的数据信息，先记录下来

在日志格式后面加上 $request_body 配置信息

log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for" $request_body';

在server中添加打印日志的操作
access_log  logs/access.log  main;　　

本以为问题解决了，开发有要求在日志中添加上 服务器响应返回的数据

目前的 nginx 是不支持输出 response 报文体的 使用body_filter_by_lua来分配请求报文体给一个nginx变量。下面是一个示例

1：下载安装LuaJIT

# wget http://luajit.org/download/LuaJIT-2.0.2.tar.gz
# tar -xzvf LuaJIT-2.0.2.tar.gz
# cd LuaJIT-2.0.2
# make
 
出现如下内容表示编译成功
OK        Successfully built LuaJIT
make[1]: Leaving directory `/usr/local/src/LuaJIT-2.0.2/src'
==== Successfully built LuaJIT 2.0.2 ====
 
# make install
出现如下内容，表示安装成功
==== Successfully installed LuaJIT 2.0.2 to /usr/local ====

2：下载准备nginx lua模块　

wget https://github.com/chaoslawful/lua-nginx-module/archive/v0.8.6.tar.gz
tar -xzvf  lua-nginx-module-0.8.6.tar.gz
mv lua-nginx-module-0.8.6  /usr/local/src/lua-nginx-module-0.8.6

3：安装nginx

tar zxf nginx-1.16.1.tar.gz
cd nginx-1.16.1
//先导入环境变量,告诉nginx去哪里找luajit
export LUAJIT_LIB=/usr/local/lib
export LUAJIT_INC=/usr/local/include/luajit-2.0

./configure --prefix=/usr/local/nginx --add-module=/usr/local/src/lua-nginx-module-0.8.6 --with-http_ssl_module --with-http_stub_status_module --with-pcre

make j2
make install　　

　常见错误处理：

/usr/local/nginx-1.4.2/sbin/nginx -v
./objs/nginx: error while loading shared libraries: libluajit-5.1.so.2: cannot open shared object file: No such file or directory
解决方法：
# ln -s /usr/local/lib/libluajit-5.1.so.2 /lib64/libluajit-5.1.so.2

4：配置Nginx

nginx配置文件加入如下配置：

location /test {
      default_type 'text/plain';
      content_by_lua 'ngx.say("hello, ttlsa lua")';
}

5：访问测试

curl http://127.0.0.1/test
hello, ttlsa lua  //使用curl测试,返回数据表示安装成功

6：Nginx日志配置

log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for" $request_body  resp_body:"$resp_body"';　　

在server中添加相应的配置：

lua_need_request_body on;

set $resp_body "";
body_filter_by_lua '
local resp_body = string.sub(ngx.arg[1], 1, 1000)
ngx.ctx.buffered = (ngx.ctx.buffered or"") .. resp_body
if ngx.arg[2] then
ngx.var.resp_body = ngx.ctx.buffered
end
';　　

如下事例：

server {
        listen         443  ssl;
        server_name  xxxx.com;

        # ssl  on;
        ssl_certificate /usr/local/nginx/conf/keys/public.pem;
        ssl_certificate_key  /usr/local/nginx/conf/keys/private.key;
        ssl_session_cache    shared:SSL:1m;
        ssl_session_timeout  5m;
        ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
        ssl_ciphers ECDH:AESGCM:HIGH:!RC4:!DH:!MD5:!3DES:!aNULL:!eNULL;
        ssl_prefer_server_ciphers  on;

        lua_need_request_body on;
        set $resp_body "";
        body_filter_by_lua '
        local resp_body = string.sub(ngx.arg[1], 1, 1000)
        ngx.ctx.buffered = (ngx.ctx.buffered or"") .. resp_body
        if ngx.arg[2] then
        ngx.var.resp_body = ngx.ctx.buffered
        end
        ';

        location / {
            proxy_pass http://127.0.0.1:8080;
            proxy_redirect off ;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header REMOTE-HOST $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header User-Agent $http_user_agent;
            proxy_set_header Referer $http_referer;
            client_max_body_size 50m;
            client_body_buffer_size 256k;
            proxy_connect_timeout 300;
            proxy_send_timeout 300;
            proxy_read_timeout 300;
            proxy_next_upstream error timeout invalid_header http_500 http_503 http_404;
            proxy_max_temp_file_size 128m;
            proxy_buffer_size 512k;
            proxy_buffers    16 512k;
            proxy_busy_buffers_size 512k;
            proxy_temp_file_write_size 512k;
        }
    access_log /tmp/faceauth.log main;

    }　　

 启动Nginx，打印日志，就可以看到相关数据。

 以上，是打印POST数据的一种方法，比较麻烦，下面介绍一种比较简单的方法：

在日志中添加“$request_body”,由于现实原因，需要添加  escape=json  转换为json格式

log_format access  escape=json '$remote_addr - $remote_user [$time_local] "$request" - "$request_body" '
                         '"$status" $body_bytes_sent "$http_referer" '
                         '"$http_user_agent" "$http_x_forwarded_for" '
                         '"$upstream_addr" "$upstream_status" "$request_time" "$upstream_response_time" $bytes_sent $request_length';